Academic Appointments

Administrative Appointments

  • Member, Molecular Imaging Program at Stanford (MIPS) (2007 - Present)
  • Member, Bio-X Program (2007 - Present)
  • Member, Stanford Cancer Center (2007 - Present)
  • Member, Canary Center at Stanford for Cancer Early Detection (2009 - Present)

Honors & Awards

  • IDEA Award, California Breast Cancer Research Program (2008)
  • Young Investigator Award, Melanoma Research Alliance (2009)
  • New Investigator Award, Department of Defense (2009)
  • Best Basic Science Paper Published in 2009, Journal of Nuclear Medicine (2010)

Professional Education

  • B.S., Sichuan University, Chemistry (1994)
  • M.S., China Institute of Atomic Energy, Radiopharmaceutical Chemistry (1997)
  • Ph.D., University of Missouri-Columbia, Chemistry (2001)

Current Research and Scholarly Interests

The overall objective of my laboratory is to develop novel molecular imaging probes and techniques for non-invasive detection of cancer and its metastasis at the earliest stage, so that cancer can be cured or transformed into a chronic, manageable disease. The techniques developed in my research will allow a close examination of the molecular, metabolic and physiological characteristics of cancers and their responses to therapy. In order to achieve this goal, my lab is aimed to identify novel cancer biomarkers with significant clinical relevance, develop new chemistry for probes preparation, and validate new strategies for probes high-throughput screening.

2021-22 Courses

All Publications

  • Medical Physics and Imaging-A Timely Perspective FRONTIERS IN PHYSICS Beyer, T., Bailey, D. L., Birk, U. J., Buvat, I., Catana, C., Cheng, Z., Fang, Q., Giove, F., Kuntner, C., Laistler, E., Moscato, F., Nekolla, S. G., Rausch, I., Ronen, I., Saarakkala, S., Thielemans, K., van Elmpt, W., Moser, E. 2021; 9
  • A convenient and efficient solid phase extraction-based pathway for purification of melanin-targeted probe 18F-P3BZA MICROCHEMICAL JOURNAL Hong, Z., Yu, B., Xiao, J., Feng, H., Ma, X., Cheng, Z., Bu, L. 2021; 164
  • A Highly Specific Multiple Enhancement Theranostic Nanoprobe for PET/MRI/PAI Image-Guided Radioisotope Combined Photothermal Therapy in Prostate Cancer. Small (Weinheim an der Bergstrasse, Germany) Xia, L., Meng, X., Wen, L., Zhou, N., Liu, T., Xu, X., Wang, F., Cheng, Z., Yang, Z., Zhu, H. 2021: e2100378


    An integrated molecular probe for combined tumor-targeted multimodal imaging and therapy in the era of precision medicine requires a multiplexed platform that simultaneously has high targeting specificity, versatile conjugation capability, and biocompatibility. Here, a novel biocompatible melanin nanoprobe (PMNs-II-813) coupled with a highly specific prostate-specific membrane antigen small molecule inhibitor is developed for the targeted multimodal diagnosis and treatment of prostate cancer. The melanin nanoparticles demonstrate photoacoustic imaging and photothermal therapy (PTT) functionalities via strong near-infrared absorption. The imaging contrast agents 89 Zr and Mn2+ are stably conjugated to the nanoparticles for positron emission tomography (PET) and magnetic resonance imaging (MRI). Fusion PET/MRI with PMNs-II-813 enables the monitoring of treatment effects in real time and lasts for more than 1 week, demonstrating the capability for multimodal theranostics in prostate cancer. Labeling with a therapeutic radionuclide, 131 I, simultaneously endows the nanoprobe with the capability for radioisotope therapy (RIT) and PTT under triple-modal imaging guidance. Combined PTT and RIT has an inhibitory effect on prostate cancer growth (tumor inhibition rate of 93% 20 days after treatment), which is significantly better than that with the single treatment. Overall, it is believed that PMNs-II-813 has potential for clinical translation to treat prostate cancer.

    View details for DOI 10.1002/smll.202100378

    View details for PubMedID 33870644

  • Synthesis and Application of a Long-Circulating Radiolabeled Peptide for Targeting of Osteosarcoma (vol 22, pg 940, 2020) MOLECULAR IMAGING AND BIOLOGY Li, Y., Li, D., Wu, H., Huang, J., Cheng, Z. 2021

    View details for DOI 10.1007/s11307-021-01598-w

    View details for Web of Science ID 000629848500001

    View details for PubMedID 33730318

  • Smart Self-Assembly Amphiphilic Cyclopeptide-Dye for Near-Infrared Window-II Imaging. Advanced materials (Deerfield Beach, Fla.) Chen, H., Shou, K., Chen, S., Qu, C., Wang, Z., Jiang, L., Zhu, M., Ding, B., Qian, K., Ji, A., Lou, H., Tong, L., Hsu, A., Wang, Y., Felsher, D. W., Hu, Z., Tian, J., Cheng, Z. 2021: e2006902


    Development of novel nanomaterials for disease theranostics represents an important direction in chemistry and precision medicine. Fluorescent molecular probes in the second near-infrared window (NIR-II, 1000-1700nm) show high promise because of their exceptional high detection sensitivity, resolution, and deep imaging depth. Here, a sharp pH-sensitive self-assembling cyclopeptide-dye, SIMM1000, as a smart nanoprobe for NIR-II imaging of diseases in living animals, is reported. This small molecule assembled nanoprobe exhibits smart properties by responding to a sharp decrease of pH in the tumor microenvironment (pH 7.0 to 6.8), aggregating from small nanoprobe (80nm at pH 7.0) into large nanoparticles (>500nm at pH 6.8) with 20-30 times enhanced fluorescence compared with the non-self-assembled CH-4T. It yields micrometer-scale resolution in blood vessel imaging and high contrast and resolution in bone and tumor imaging in mice. Because of its self-aggregation in acidic tumor microenvironments in situ, SIMM1000 exhibits high tumor accumulation and extremely long tumor retention (>19 days), while being excretable from normal tissues and safe. This smart self-assembling small molecule strategy can shift the paradigm of designing new nanomaterials for molecular imaging and drug development.

    View details for DOI 10.1002/adma.202006902

    View details for PubMedID 33709533

  • Biodegradable Silica-Based Nanotheranostics for Precise MRI/NIR-II Fluorescence Imaging and Self-Reinforcing Antitumor Therapy. Small (Weinheim an der Bergstrasse, Germany) Zheng, Z., Jia, Z., Qu, C., Dai, R., Qin, Y., Rong, S., Liu, Y., Cheng, Z., Zhang, R. 2021: e2006508


    Multi-modality cancer diagnosis techniques based on the second near-infrared window fluorescence (NIR-II FL, 1000-1700 nm) imaging have become the focus of research attention. For such multimodality probes, how to take advantage of the tumor microenvironments (TME) characteristics to better image diseases and combine efficient therapeutics to achieve theranostics is still a big challenge. Herein, a novel TME-activated nanosystem (FMSN-MnO2 -BCQ) employing degradable silica-based nanoplatform is designed, adjusting the ratio of intratumoral hydrogen peroxide (H2 O2 )/glutathione (GSH) for magnetic resonance imaging (MRI)/NIR-II FL imaging and self-reinforcing chemodynamic therapy (CDT). Innovative bovine serum albumin (BSA)-modified fusiform-like mesoporous silica nanoparticles (FMSN) is fabricated as a carrier for NIR-II small molecule (CQ4T) and MRI reporter MnO2 . Remarkably, the BSA modification helped to achieve the dual-functions of high biocompatibility and enhance NIR-II fluorescence. The FMSN-MnO2 -BCQ with FMSN framework featuring a stepwise degradability in tumor interior released MnO2 and BCQ nanoparticles. Through the specific degradation of MnO2 by the TME, the produced Mn2+ ions are effectively exerted Fenton-like activity to generate hydroxyl radical (OH) from endogenous H2 O2 to eradicate tumor cells. More importantly, the GSH depletion due to the synergistic effect of tetrasulfide bond and MnO2 in turn induced the oxidative cytotoxicity for self-reinforcing CDT.

    View details for DOI 10.1002/smll.202006508

    View details for PubMedID 33569918

  • PET Imaging of Melanoma Using Melanin-Targeted Probe. Methods in molecular biology (Clifton, N.J.) Ma, X., Cheng, Z. 2021; 2265: 407–16


    Melanin exists in the most of melanoma lesions. Melanin plays an important role in melanoma progression, metastasis, therapy response, and the overall survival of patients. Therefore, melanin is a critical target for melanoma diagnosis and therapy. Many melanin targeting probes, such as radioisotope-labeled benzamide analogs, have been developed for melanoma diagnosis using positron emission tomography (PET). The N-(2-(diethylamino)-ethyl)-18F-5-fluoropicolinamide (18F-P3BZA) probe is one of the benzamide analogs and has been preliminarily tested for clinical diagnosis of melanoma in our recent studies. It has shown high specificity and favorable in vivo performance for PET of melanoma. Herein, we describe the detailed synthesis protocol of 18F-P3BZA and PET/CT imaging procedure for animal models and patients.

    View details for DOI 10.1007/978-1-0716-1205-7_29

    View details for PubMedID 33704730

  • Development and validation of a clinically applicable deep learning strategy (HONORS) for pulmonary nodule classification at CT: A retrospective multicentre study. Lung cancer (Amsterdam, Netherlands) Lv, W. n., Wang, Y. n., Zhou, C. n., Yuan, M. n., Pang, M. n., Fang, X. n., Zhang, Q. n., Huang, C. n., Li, X. n., Zhou, Z. n., Yu, Y. n., Wang, Y. n., Lu, M. n., Xu, Q. n., Li, X. n., Lin, H. n., Lu, X. n., Xu, Q. n., Sun, J. n., Tang, Y. n., Yan, F. n., Zhang, B. n., Cheng, Z. n., Zhang, L. n., Lu, G. n. 2021; 155: 78–86


    To propose a practical strategy for the clinical application of deep learning algorithm, i.e., Hierarchical-Ordered Network-ORiented Strategy (HONORS), and a new approach to pulmonary nodule classification in various clinical scenarios, i.e., Filter-Guided Pyramid NETwork (FGP-NET).We developed and validated FGP-NET on a collection of 2106 pulmonary nodules on computed tomography images which combined screened and clinically detected nodules, and performed external test (n = 341). The area under the curves (AUCs) of FGP-NET were assessed. A comparison study with a group of 126 skilled radiologists was conducted. On top of FGP-NET, we built up our HONORS which was composed of two solutions. In the Human Free Solution, we used the high sensitivity operating point for screened nodules, but the high specificity operating point for clinically detected nodules. In the Human-Machine Coupling Solution, we used the Youden point.FGP-NET achieved AUCs of 0.969 and 0.847 for internal and external test. The AUCs of the subsets of the external test set ranged from 0.890 to 0.942. The average sensitivity and specificity of the 126 radiologists were 72.2 ± 15.1 % and 71.7 ± 15.5 %, respectively, while a higher sensitivity (93.3 %) but a relatively inferior specificity (64.0 %) were achieved by FGP-NET. HONORS-guided FGP-NET identified benign nodules with high sensitivity (sensitivity,95.5 %; specificity, 72.5 %) in the screened nodules, and identified malignant nodules with high specificity (sensitivity, 31.0 %; specificity, 97.5 %) in the clinically detected nodules. These nodules could be reliably diagnosed without any intervention from radiologists, via the Human Free Solution. The remaining ambiguous nodules were diagnosed with high performance, which however required manual confirmation by radiologists, via the Human-Machine Coupling Solution.FGP-NET performed comparably to skilled radiologists in terms of diagnosing pulmonary nodules. HONORS, due to its high performance, might reliably contribute a second opinion, aiding in optimizing the clinical workflow.

    View details for DOI 10.1016/j.lungcan.2021.03.008

    View details for PubMedID 33761380

  • Copper(II)-Disulfiram Loaded Melanin-Dots for Cancer Theranostics. Nanomedicine : nanotechnology, biology, and medicine Shi, H., Suo, Y., Zhang, Z., Liu, R., Liu, H., Cheng, Z. 2020: 102340


    Copper(II) diethyldithiocarbamate complex (CuET), the metabolite of disulfiram complexed with copper, is the component responsible for cancer treatment efficacy of disulfiram. But the hydrophobic property of CuET limits its use in vivo, and an appropriate drug delivery system needs to be developed. Ultrasmall melanin nanoparticle (M-Dots) with excellent biosafety and biocompatibility properties has been synthesized in our previous studies. Herein we prepared CuET loaded with M-Dots through hydrophobic interaction, which could enhance the water solubility significantly. After the administration of M-Dots-CuET in mice tumor models, the nanoparticles showed good tumor accumulation as evidenced by the enhanced photoacoustic signal in tumor regions. M-Dots-CuET also displayed excellent tumor inhibition capability, and the tumor growth inhibition value (TGI) was 45.1%. When combined with photothermal therapy, the TGI reached up to 78.6%. In summary, M-Dots-CuET provides a new potential strategy for cancer theranostics.

    View details for DOI 10.1016/j.nano.2020.102340

    View details for PubMedID 33227540

  • In vivo live imaging of bone using shortwave infrared fluorescent quantum dots. Nanoscale Che, Y., Feng, S., Guo, J., Hou, J., Zhu, X., Chen, L., Yang, H., Chen, M., Li, Y., Chen, S., Cheng, Z., Luo, Z., Chen, J. 2020


    Bone plays an increasingly critical role in human health and disease. More noninvasive multi-scale imaging techniques are urgently required for investigations on the substructures and biological functions of bones. Our results firstly revealed that SWIR QDs prepared by us acted as a bone-specific imaging contrast to achieve real-time observation of bone structures both in vivo and ex vivo. The major bone structures of both Balb/C nude mice and Balb/C mice including their skull, spine, pelvis, limbs, and sternum could be rapidly and gradually identified via blood circulation after QD injection in vivo. More importantly, the binding capability of our QDs mainly depended on the biological activities of bone tissues, suggesting that our technique is suitable for in vivo live imaging. In addition, the cell imaging results suggested that the potential mechanism of our bone imaging could be ascribed to the highly specific interaction between QDs and MC3T3-E1 cells. In a word, the skeletal structures and biological activities of bones are anticipated to be observed and monitored with this QD-guided SWIR imaging strategy, respectively. This radiation-free QD-guided SWIR live imaging of bone can add new insights into a comprehensive study of bones in vivo and provide a basis for early diagnosis of bone diseases.

    View details for DOI 10.1039/d0nr06261h

    View details for PubMedID 33141143

  • Nanoparticle-enhanced chemo-immunotherapy to trigger robust antitumor immunity. Science advances Liang, J., Wang, H., Ding, W., Huang, J., Zhou, X., Wang, H., Dong, X., Li, G., Chen, E., Zhou, F., Fan, H., Xia, J., Shen, B., Cai, D., Lan, P., Jiang, H., Ling, J., Cheng, Z., Liu, X., Sun, J. 2020; 6 (35): eabc3646


    Mounting evidence suggests that immunotherapies are a promising new class of anticancer therapies. However, the immunosuppressive tumor microenvironment (TME), poor immunogenicity, and off-target toxicity hinder the broader implementation of immunotherapies. Here, we describe a novel strategy combining chemotherapy and immunotherapy to modulate the TME by systemically and concurrently delivering the chemotherapeutic agent SN38 (7-ethyl-10-hydroxycamptothecin) and the STING agonist DMXAA (5,6-dimethylxanthenone-4-acetic acid) into tumors using triblock copolymer nanoparticles, named PS3D1@DMXAA, which enhances antigen cross-presentation and induces the conversion of the immunosuppressive TME to immunogenic TME through the newly found synergistic function between SN38 and STING activation. PS3D1@DMXAA thus shows potent therapeutic efficacy in three mice tumor models and elicits remarkable therapeutic benefit when combined with anti-PD-1 therapy. Our engineered nanosystem offers a rational design of an effective immunotherapy combination regimen to convert uninflamed "cold" tumors into "hot" tumors, addressing the major challenges immunotherapies faced.

    View details for DOI 10.1126/sciadv.abc3646

    View details for PubMedID 32923651

  • Reactive oxygen species and enzyme dual-responsive biocompatible drug delivery system for targeted tumor therapy. Journal of controlled release : official journal of the Controlled Release Society Zhao, N., Ding, B., Zhang, Y., Klockow, J. L., Lau, K., Chin, F. T., Cheng, Z., Liu, H. 2020


    Spurred by newly developed drug delivery systems (DDSs), side effects of cancer chemotherapy could be reduced by using multifunctional nanoplatforms. However, the facile synthesis of effective DDSs remains a challenge. Here, a six-arginine-tailed anti-epidermal growth factor receptor (EGFR) affibody was employed to easily synthesize the highly reactive oxygen species (hROS)- and trypsin-responsive 11-mercaptoundecanoic acid-modified gold nanoclusters (MUA-Au NCs) for tumor-targeted drug delivery. The polyarginine moiety of affibody sealed methotrexate (MTX)-loaded MUA-Au NCs through charge effect, as well as leaving the rest targeting fragment of the affibody to specifically bind tumor overexpressed EGFR. As the shell of MUA-Au NCs-MTX-Affibody (MAMA), polyarginine chains of affibody could be digested by trypsin, helping to release MTX from MAMA. The released MTX accelerated destroying MUA-Au NCs through inducing the generation of hROS. Specifically targeting EGFR-overexpressed tumors, quickly delivering a sufficient amount of drug to the tumor, subsequently increasing the local MTX and hROS levels, and safely eliminating the biocompatible structure from kidney, endowed MAMA greater treatment effectiveness and lower side effect than chemotherapy, especially in pancreatic cancer due to its high trypsin level. This simply fabricated DDS may find applications in high effective cancer therapy, especially for tumors with high trypsin activity.

    View details for DOI 10.1016/j.jconrel.2020.05.031

    View details for PubMedID 32450093

  • Non-Invasive Photoacoustic Imaging of In Vivo Mice with Erythrocyte Derived Optical Nanoparticles to Detect CAD/MI. Scientific reports Liu, Y., Hanley, T., Chen, H., Long, S. R., Gambhir, S. S., Cheng, Z., Wu, J. C., Fakhri, G. E., Anvari, B., Zaman, R. T. 2020; 10 (1): 5983


    Coronary artery disease (CAD) causes mortality and morbidity worldwide. We used near-infrared erythrocyte-derived transducers (NETs), a contrast agent, in combination with a photoacoustic imaging system to identify the locations of atherosclerotic lesions and occlusion due to myocardial-infarction (MI). NETs (90nm diameter) were fabricated from hemoglobin-depleted mice erythrocyte-ghosts and doped with Indocyanine Green (ICG). Ten weeks old male C57BL/6 mice (n=9) underwent left anterior descending (LAD) coronary artery ligation to mimic vulnerable atherosclerotic plaques and their rupture leading to MI. 150L of NETs (20M ICG,) was IV injected via tail vein 1-hour prior to photoacoustic (PA) and fluorescence in vivo imaging by exciting NETs at 800nm and 650nm, respectively. These results were verified with histochemical analysis. We observed 256-fold higher PA signal from the accumulated NETs in the coronary artery above the ligation. Fluorescence signals were detected in LAD coronary, thymus, and liver. Similar signals were observed when the chest was cut open. Atherosclerotic lesions exhibited inflammatory cells. Liver demonstrated normal portal tract, with no parenchymal necrosis, inflammation, fibrosis, or other pathologic changes, suggesting biocompatibility of NETs. Non-invasively detecting atherosclerotic plaques and stenosis using NETs may lay a groundwork for future clinical detection and improving CAD risk assessment.

    View details for DOI 10.1038/s41598-020-62868-1

    View details for PubMedID 32249814

  • Cancer cell membrane-coated rare earth doped nanoparticles for tumor surgery navigation in NIR-II imaging window CHEMICAL ENGINEERING JOURNAL Zhang, X., He, S., Ding, B., Qu, C., Zhang, Q., Chen, H., Sun, Y., Fang, H., Long, Y., Zhang, R., Lan, X., Cheng, Z. 2020; 385
  • Novel anilino quinazoline-based EGFR tyrosine kinase inhibitors for treatment of non-small cell lung cancer. Biomaterials science Yang, L., Liu, S., Chu, J., Miao, S., Wang, K., Zhang, Q., Wang, Y., Xiao, Y., Wu, L., Liu, Y., Yu, L., Yu, C., Liu, X., Ke, M., Cheng, Z., Sun, X. 2020


    The epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of non-small cell lung cancer (NSCLC). EGFR-TKI positron emission tomography (PET) probes based on the central quinazoline core show great potential for NSCLC diagnosis, and pre-clinical and clinical therapy monitoring. In our previous research, anilino quinazoline based PET probe, N-(3-chloro-4-fluorophenyl)-7-(2-(2-(2-(2-18F-fluoroethoxy) ethoxy) ethoxy) ethoxy)-6-methoxyquinazolin-4-amine (18F-MPG), have been developed, and it has been successfully demonstrated to be a powerful non-invasive imaging tool for differentiating EGFR mutation status and stratifying NSCLC patients for EGFR-TKI treatment in a clinical study (n = 75 patients). Moreover, it has been found that 18F-MPG shows excellent tumor targeting performance and good pharmacokinetic characteristics in NSCLC patients. These results motivate us to investigate the cancer treatment efficacy of non-radioactive F-MPG and its analogue N-(3-chloro-4-fluorophenyl)-7-(2-(2-(2-(2-hydroxyethoxy)ethoxy) ethoxy) ethoxy)-6-methoxyquinazolin-4-amine (OH-MPG) in vitro and in small animal models. Our studies revealed that both F-MPG and OH-MPG displayed high therapeutic effect to NSCLC cells (IC50 = 5.3 nM and 2.0 nM to HCC827 cells for F-MPG and OH-MPG, respectively). More importantly, compared with a standard EGFR-TKI, 4-(3-bromoanilino)-6,7-dimethoxyquinazoline (PD153035), F-MPG and OH-MPG showed stronger tumor inhibition in preclinical models. Furthermore, the treatment efficacy of F-MPG or OH-MPG monitored by 18F-FDG-PET indicated that tumor uptake in treated groups was significantly decreased. Ex vivo experiments showed that the levels of serum biomarkers and pathological changes in the liver were significantly reduced in the F-MPG and OH-MPG group, compared to PD153035 treated group. In conclusion, EGFR targeted F-MPG and OH-MPG exhibit promising anti-tumor activity with limited liver damage, thus representing promising drug candidates for further investigation for combating the deadly NSCLC.

    View details for DOI 10.1039/d0bm00293c

    View details for PubMedID 32236267

  • Radiolabeled peptide probes for liver cancer imaging. Current medicinal chemistry Cao, R., Liu, H., Cheng, Z. 2020


    Liver cancer/hepatocellular carcinoma (HCC) is a leading cause of cancer death and represents an important cause of mortality worldwide. Several biomarkers are overexpressed in liver cancer, such as the glypican 3 (GPC3) and epidermal growth factor receptor (EGFR). These biomarkers play important roles in the progression of tumors and could serve as imaging and therapeutic targets for this disease. Peptides with adequate stability, receptor binding properties, and biokinetic behavior have been intensively studied for liver cancer imaging. A great variety of them have been radiolabeled with clinically relevant radionuclides for liver cancer diagnosis, and many are promising imaging and therapeutic candidates for clinical translation. Herein, we summarize the advancement of radiolabeled peptides for the targeted imaging of liver cancer.

    View details for DOI 10.2174/0929867327666200320153837

    View details for PubMedID 32196443

  • A thiopyrylium salt for PET/NIR-II tumor imaging and image-guided surgery. Molecular oncology Zhang, X., Ding, B., Qu, C., Li, H., Sun, Y., Gai, Y., Chen, H., Fang, H., Qian, K., Zhang, Y., Cheng, Z., Lan, X. 2020


    All tumor imaging modalities have resolution limits below which deeply-situated small metastatic foci may not be identified. Moreover, incomplete lesion excision will affect the outcomes of the patients. Scintigraphy is adept in locating lesions, and second near-infrared window (NIR-II) imaging may allow precise real-time tumor delineation. To achieve complete excision of all lesions, multimodality imaging is a promising method for tumor identification and management. Here, a NIR-II thiopyrylium salt, XB1034, was first synthesized and bound to cetuximab and trans-cyclooctene (TCO) to produce XB1034-cetuximab-TCO. This probe provides excellent sensitivity and high temporal resolution NIR-II imaging in mice bearing tumors developed from human breast cancer cells MDA-MB-231. To enable PET imaging, 68 Ga-NETA-tetrazine is subsequently injected into the mice to undergo a bioorthogonal reaction with the pre-injected XB1034-cetuximab-TCO. PET images achieved in the tumor models using the pretargeting strategy are of much higher quality than those obtained using the direct radiolabeling method. Moreover, real-time NIR-II imaging allows accurate tumor excision and sentinel lymph node mapping. In conclusion, XB1034 is a promising molecular imaging probe for tumor diagnosis and treatment.

    View details for DOI 10.1002/1878-0261.12674

    View details for PubMedID 32191387

  • Synthesis and Application of a Long-Circulating Radiolabeled Peptide for Targeting of Osteosarcoma. Molecular imaging and biology Li, Y., Li, D., Wu, H., Huang, J., Cheng, Z. 2020


    PURPOSE: The small peptide TMTP1 (NVVRQ) has been proved to target a series of highly metastatic tumor cells. The aim of this study was to develop a new agent based on TMTP1 conjugated with Evans blue (EB), to increase tumor uptake and modify the pharmacokinetic characteristics of the resulting radiolabeled agent.PROCEDURES: DOTA-EB-TMTP1 was prepared through conventional solid-phase peptide synthesis chemistry. Then, it was successfully labeled with Cu-64 to obtain [64Cu]DOTA-EB-TMTP1. The tumor targeting properties were evaluated in vivo using 143B xenografts.RESULTS: DOTA-EB-TMTP1 was successfully labeled with Cu-64 in a yield of 87.3±5.2%. In a small animal positron emission tomography/X-ray computed tomography (PET/CT) study in osteosarcoma 143B xenograft mice, [64Cu]DOTA-EB-TMTP1 was found to rapidly accumulate in the tumor tissue. The tumor uptake increased over time and reached a plateau of 6.50±0.88% ID/g 8h after tail vein injection. The radioactivity remained in the tumor tissue 48h postinjection with a negligible decrease.CONCLUSIONS: Overall, the introduction of the EB motif to TMTP1 significantly changed its pharmacokinetics in vivo, and this strategy fulfills the purpose of prolonging the blood circulation and enhancing the tumor uptake. [64Cu]DOTA-EB-TMTP1 is a promising agent for osteosarcoma targeting. Moreover, our study highlights that DOTA-EB-TMTP1 is a good candidate for labeling with different radionuclides for potential theranostic applications.

    View details for DOI 10.1007/s11307-019-01468-6

    View details for PubMedID 31907847

  • Polydopamine-coated downconversion nanoparticle as an efficient dual-modal near-infrared-II fluorescence and photoacoustic contrast agent for non-invasive visualization of gastrointestinal tract in vivo. Biosensors & bioelectronics Ma, L. n., Huang, S. n., He, S. n., Wang, Z. n., Cheng, Z. n. 2020; 151: 112000


    Herein, a multifunctional dual-modal imaging probe is successfully developed to integrate the advantages of second near-infrared window (NIR-II, 1000-1700 nm) fluorescence imaging (FI) and photoacoustic imaging (PAI) with the ultimate goal of improving diseases diagnosis and management. Melanin-inspired polydopamine (PDA) polymer coated NaYF4:Yb3+,Er3+@NaYbF4@NaYF4:Nd3+ down conversion nanoparticles (DCNPs) is designed via water-in-oil microemulsion method, which comprises a DCNP core, acting as the NIR-II optical imaging agent, and a PDA shell, acting as the PA contrast agent. By taking the advantages of high spatial resolution and excellent temporal resolution, the dual-modal contrast agent is capable for high sensitivity real-time visualization of gastrointestinal tract, diagnosis of gastrointestinal peristalsis disorder and NIR-II FI-guided intestinal obstruction surgery. All of the above results demonstrate the great potential of DCNP@PDA NP as an efficient NIR-II/PAI dual-modal contrast agent for precision medicine.

    View details for DOI 10.1016/j.bios.2019.112000

    View details for PubMedID 31999595

  • MMP activatable nanoprobe for MRI of aortic aneurysms. Nanomedicine : nanotechnology, biology, and medicine Yao, Y. n., Cheng, K. n., Cheng, Z. n. 2020: 102177


    Matrix metalloproteinases (MMPs) activation contributes to abdominal aortic aneurysm (AAA) growth and rupture. The study was to evaluate the ability of a novel activatable magnetic resonance imaging (MRI) nanoprobe, to target MMPs in an Angiotensin II (ANG II)-induced AAA model. The activatable nanoprobe is composed by a hydrophilic polyethylene glycol coating layer immobilized on the external surface of core/shell Fe/iron oxide nanoparticles, between them, there was grafted the MMP peptide substrate. In the ANG II infusion mice model of AAAs, MRI was performed to characterize the progression of model. The contrast-to-noise ratio was lower in the aneurysm of the mice injected with activatable nanoprobe. Histological studies revealed the presence of MMPs and iron-oxide in regions of MR signal decrease. MRI combined with nanoprobe allows the detection of MMP activity within the wall of AAA, thus representing a potential noninvasive method to predict the rupture risk of AAA.

    View details for DOI 10.1016/j.nano.2020.102177

    View details for PubMedID 32142755

  • 64Cu-labeled Melanin nanoparticles for PET/CT and radionuclide therapy of tumor. Nanomedicine : nanotechnology, biology, and medicine Zhou, H. n., Zhang, Q. n., Cheng, Y. n., Xiang, L. n., Shen, G. n., Wu, X. n., Cai, H. n., Li, D. n., Zhu, H. n., Zhang, R. n., Li, L. n., Cheng, Z. n. 2020: 102248


    Melanin is a group of natural pigments found in living organism. It can be used for positron emission tomography (PET) imaging due to its inherent chelating ability to radioactive cupric ion. This study was to prepare 64Cu-labeled PEGylated Melanin nanoparticles (64Cu-PEG-MNPs), and to further take advantage of the enhanced permeability and retention (EPR) effect of radiolabeled nanoparticles to realize the integration of tumor diagnosis and treatment. We successfully synthesized PEG-MNPs. Saline and serum stability experiments demonstrating good stability. PET/CT showed high tumor aggregation. Moreover, 64Cu-PEG-MNPs resulted in a therapeutic effect on the A431 tumor-bearing mice in the treatment group. The pathological results further confirmed that the therapeutic doses of 64Cu-PEG-MNPs cause pathological changes of tumor tissues while showing minimal toxicity to normal tissues. Our data successfully demonstrate the good imaging performance of 64Cu-PEG-MNPs on A431 tumors and further proved its therapeutic effect, highlighting a great potential in targeted radionuclide therapy.

    View details for DOI 10.1016/j.nano.2020.102248

    View details for PubMedID 32574686

  • An NIR-II/MR dual modal nanoprobe for liver cancer imaging. Nanoscale Ren, Y. n., He, S. n., Huttad, L. n., Chua, M. S., So, S. K., Guo, Q. n., Cheng, Z. n. 2020


    Hepatocellular carcinoma (HCC) is a malignancy of the liver worldwide and surgical resection remains the most effective treatment. However, it is still a great challenge to locate small lesions and define the border of diffused HCC even with the help of preoperative imaging examination. Here, we reported a rare-earth-doped nanoparticle NaGdF4:Nd 5%@NaGdF4@Lips (named Gd-REs@Lips), which simultaneously performed powerful functions in both magnetic resonance imaging (MRI) and second near-infrared fluorescence window imaging (NIR-II, 1000-1700 nm). Imaging studies on orthotopic models with xenografts established from HCC patients indicated that Gd-REs@Lips efficiently worked as a T2-weighted imaging contrast agent to increase the signal intensity difference between liver cancer tissues and surrounding normal liver tissues on MRI, and it can also serve as a negative NIR-II imaging contrast enabling the precise detection of liver cancer. More importantly, benefiting from the high sensitivity of NIR-II imaging, Gd-REs@Lips allowed the visualization of tiny metastasis lesions (2 mm) on the liver surface. It is expected that the dual NIR-II/MRI modal nanoprobe developed holds high potential to fill the gap between the preoperative imaging detection of cancer lesions and intra-operative guidance, and it further brings new opportunities to address HCC-related medical challenges.

    View details for DOI 10.1039/d0nr00075b

    View details for PubMedID 32428058

  • The Optimal Outcome of Suppressing Ewing Sarcoma Growth in vivo With Biocompatible Bioengineered miR-34a-5p Prodrug. Frontiers in oncology Li, D. F., Yuan, Y. n., Tu, M. J., Hu, X. n., Li, Y. Z., Yi, W. R., Li, P. C., Zhao, Y. n., Cheng, Z. n., Yu, A. M., Jian, C. n., Yu, A. X. 2020; 10: 222


    Being the second most common type of primary bone malignancy in children and adolescents, Ewing Sarcoma (ES) encounters the dilemma of low survival rate with a lack of effective treatments. As an emerging approach to combat cancer, RNA therapeutics may expand the range of druggable targets. Since the genome-derived oncolytic microRNA-34a (miR-34a) is down-regulated in ES, restoration of miR-34a-5p expression or function represents a new therapeutic strategy which is, however, limited to the use of chemically-engineered miRNA mimics. Very recently we have developed a novel bioengineering technology using a stable non-coding RNA carrier (nCAR) to achieve high-yield production of biocompatible miRNA prodrugs, which is a great addition to current tools for the assessment of RNA therapeutics. Herein, for the first time, we investigated the biochemical pharmacology of bioengineered miR-34a-5p prodrug (nCAR/miR-34a-5p) in the control of ES using human ES cells and xenograft mouse models. The bioengineered nCAR/miR-34a-5p was precisely processed to mature miR-34a-5p in ES cells and subsequently suppressed cell proliferation, attributable to the enhancement of apoptosis and induction of G2 cell cycle arrest through downregulation of SIRT-1, BCL-2 and CDK6 protein levels. Furthermore, systemic administration of nCAR/miR-34a-5p dramatically suppressed the ES xenograft tumor growth in vivo while showing biocompatibility. In addition, the antitumor effect of bioengineered nCAR/miR-34a-5p was associated with a lower degree of tumoral cell proliferation and greater extent of apoptosis. These findings demonstrate the efficacy of bioengineered miR-34a-5p prodrug for the treatment of ES and support the development of miRNA therapeutics using biocompatible bioengineered miRNA prodrugs.

    View details for DOI 10.3389/fonc.2020.00222

    View details for PubMedID 32161722

    View details for PubMedCentralID PMC7052494

  • 18 F-FDG PET/CT imaging of small intestinal metastasis from pulmonary sarcomatoid carcinoma: Brief report and review of the literature. Thoracic cancer Xie, X. n., Tu, N. n., Wang, Q. n., Cheng, Z. n., Han, X. n., Bu, L. n. 2020


    We herein report two cases of small intestinal metastasis from pulmonary sarcomatoid carcinoma (PSC) detected by 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG PET/CT). We reviewed the literature on 18 F-FDG PET/CT features in gastrointestinal metastasis of PSC patients since 1992, and further analyzed the imaging features. According to the literature review, 23 eligible cases were identified from eight studies, and no cases underwent 18 F-FDG PET/CT imaging. In this study, clinical and PET/CT imaging data of two patients are reported. In our cases, clinical and the CT images of lung masses were not typical, but the uptake of 18 F-FDG was remarkably high, with SUVmax exceeding 30. Small intestinal metastases may not be related to obstruction, or even the local intestinal cavity may be dilated. Therefore, in PSC patients with mild or without abdominal symptoms, 18 F-FDG PET/CT imaging could identify intestinal metastasis at a relatively early stage and may be used to determine the preferred biopsy site, or early intervention by surgery. KEY POINTS: 18 F-FDG PET/CT imaging of small intestinal metastasis of PSC has not been previously reported in the literature and here we report the 18 F-FDG PET/CT features of two cases. The uptake of 18 F-FDG was remarkably high in both the primary tumor and metastatic intestinal lesion. 18 F-FDG PET/CT imaging may therefore be used to determine the preferred biopsy site or early intervention by surgery.

    View details for DOI 10.1111/1759-7714.13468

    View details for PubMedID 32410331

  • Deep-Tissue Photothermal Therapy Using Laser Illumination at NIR-IIa Window NANO-MICRO LETTERS Wu, X., Suo, Y., Shi, H., Liu, R., Wu, F., Wang, T., Ma, L., Liu, H., Cheng, Z. 2020; 12 (1)
  • NIRF Nanoprobes for Cancer Molecular Imaging: Approaching Clinic. Trends in molecular medicine Hu, Z. n., Chen, W. H., Tian, J. n., Cheng, Z. n. 2020; 26 (5): 469–82


    Near-IR fluorescence imaging (NIRFI) is a highly promising technique for improving cancer theranostics in the era of precision medicine. Through the combination with cutting-edge bionanotechnologies, the potential of NIRFI can be greatly broadened. A variety of novel NIRF nanoprobes has been developed with ultimate goals of addressing unmet medical needs. Here, we present recent breakthroughs on the fundamental aspects of NIRFI, such as imaging at long wavelengths (1000-1700 nm), and the use of new approaches (X-rays, chemiluminescence, radioluminescence, etc.) for the excitation of novel nanoprobes. Within two decades, research on NIRF nanoprobes has translated to clinical trials and it will further translate to cancer management.

    View details for DOI 10.1016/j.molmed.2020.02.003

    View details for PubMedID 32359478

  • Visualization of diagnostic and therapeutic targets in glioma with molecular imaging Frontiers in Immunology Li, D., Patel, C. B., Xu, G., Iagaru, A., Zhu, Z., Zhang, L., Cheng, Z. 2020
  • First-in-class humanized FSH blocking antibody targets bone and fat. Proceedings of the National Academy of Sciences of the United States of America Gera, S. n., Sant, D. n., Haider, S. n., Korkmaz, F. n., Kuo, T. C., Mathew, M. n., Perez-Pena, H. n., Xie, H. n., Chen, H. n., Batista, R. n., Ma, K. n., Cheng, Z. n., Hadelia, E. n., Robinson, C. n., Macdonald, A. n., Miyashita, S. n., Williams, A. n., Jebian, G. n., Miyashita, H. n., Gumerova, A. n., Ievleva, K. n., Smith, P. n., He, J. n., Ryu, V. n., DeMambro, V. n., Quinn, M. A., Meseck, M. n., Kim, S. M., Kumar, T. R., Iqbal, J. n., New, M. I., Lizneva, D. n., Rosen, C. J., Hsueh, A. J., Yuen, T. n., Zaidi, M. n. 2020


    Blocking the action of FSH genetically or pharmacologically in mice reduces body fat, lowers serum cholesterol, and increases bone mass, making an anti-FSH agent a potential therapeutic for three global epidemics: obesity, osteoporosis, and hypercholesterolemia. Here, we report the generation, structure, and function of a first-in-class, fully humanized, epitope-specific FSH blocking antibody with a KD of 7 nM. Protein thermal shift, molecular dynamics, and fine mapping of the FSH-FSH receptor interface confirm stable binding of the Fab domain to two of five receptor-interacting residues of the FSHβ subunit, which is sufficient to block its interaction with the FSH receptor. In doing so, the humanized antibody profoundly inhibited FSH action in cell-based assays, a prelude to further preclinical and clinical testing.

    View details for DOI 10.1073/pnas.2014588117

    View details for PubMedID 33127753

  • Gold Nanoclusters for NIR-II Fluorescence Imaging of Bones. Small (Weinheim an der Bergstrasse, Germany) Li, D. n., Liu, Q. n., Qi, Q. n., Shi, H. n., Hsu, E. C., Chen, W. n., Yuan, W. n., Wu, Y. n., Lin, S. n., Zeng, Y. n., Xiao, Z. n., Xu, L. n., Zhang, Y. n., Stoyanova, T. n., Jia, W. n., Cheng, Z. n. 2020: e2003851


    Fluorescence imaging in the second near-infrared window (NIR-II, 1000-1700 nm) holds great promise for deep tissue visualization. Development of novel clinical translatable NIR-II probes is crucial for realizing the medical applications of NIR-II fluorescence imaging. Herein, the glutathione-capped gold nanoclusters (AuNCs, specifically Au25 (SG)18 ) demonstrate highly efficient binding capability to hydroxyapatite in vitro for the first time. Further in vivo NIR-II fluorescence imaging of AuNCs indicate that they accumulate in bone tissues with high contrast and signal-background ratio. AuNCs are also mainly and quickly excreted from body through renal system, showing excellent ribs and thoracic vertebra imaging because of no background signal in liver and spleen. The deep tissue penetration capability and high resolution of AuNCs in NIR-II imaging render their great potential for fluorescence-guided surgery like spinal pedicle screw implantation. Overall, AuNCs are highly promising and clinical translatable NIR-II imaging probe for visualizing bone and bone related abnormalities.

    View details for DOI 10.1002/smll.202003851

    View details for PubMedID 33000882

  • An IR820 Dye-Protein Complex for Second Near-Infrared Window and Photoacoustic Imaging ADVANCED OPTICAL MATERIALS Du, B., Qu, C., Qian, K., Ren, Y., Li, Y., Cui, X., He, S., Wu, Y., Ko, T., Liu, R., Li, X., Li, Y., Cheng, Z. 2019
  • Tuning the near infrared II emitting wavelength of small molecule dyes by single atom alteration. Chemical communications (Cambridge, England) Qian, K., Qu, C., Ma, X., Chen, H., Kandawa-Schulz, M., Song, W., Miao, W., Wang, Y., Cheng, Z. 2019


    A series of small molecule dyes demonstrate the feasibility of manipulating Near Infrared II emission by simply altering the donors' heteroatoms, which involved both electronegativity and intramolecular steric effects. Furthermore, these dyes show high resolution and stability for in vivo imaging after being complexed with human serum albumin.

    View details for DOI 10.1039/c9cc08434g

    View details for PubMedID 31821402

  • Excretable Lanthanide Nanoparticle for Biomedical Imaging and Surgical Navigation in the Second Near-Infrared Window. Advanced science (Weinheim, Baden-Wurttemberg, Germany) Li, D., He, S., Wu, Y., Liu, J., Liu, Q., Chang, B., Zhang, Q., Xiang, Z., Yuan, Y., Jian, C., Yu, A., Cheng, Z. 2019; 6 (23): 1902042


    Recently, various second near-infrared window (NIR-II, 1000-1700 nm) fluorophores have been synthesized for in vivo imaging with nonradiation, high resolution, and low autofluorescence. However, most of the NIR-II fluorophores, especially inorganic nanoprobes, are mainly retained in the reticuloendothelial system (RES) such as the liver and spleen, leading to long-term safety concerns. Herein, a type of lanthanide-based excretable NIR-II nanoparticle, RENPs@Lips, which can be quickly cleared out of body after intravenous administration with half-lives of 23.0 h for the liver and 14.9 h for the spleen, is reported. Interestingly, over 90% of RENPs@Lips can be excreted through a hepatobiliary system within 72 h postinjection. The moderate blood half-time (T 1/2 = 17.96 min) allows for multifunctional applications in delineating the hemodynamics of vascular disorders (artery thrombosis, ischemia, and tumor angiogenesis) and monitoring blood perfusion in response to acute ischemia. In addition, RENPs@Lips exhibit high performance in identifying orthotopic tumor vessels intraoperatively and embolization surgery under NIR-II imaging navigation. Moreover, excellent signal-to-background ratio (SBR) is successfully achieved to facilitate sentinel lymph nodes biopsy (SLNB) with tumor-bearing mice. The high biocompatibility, favorable excretability, and outstanding optical properties warrant RENPs@Lips as novel promising NIR-II nanoparticles for future applications and translation into an interdisciplinary amalgamation of research in diverse fields.

    View details for DOI 10.1002/advs.201902042

    View details for PubMedID 31832325

  • Monitoring the Real-Time Circulatory System-Related Physiological and Pathological Processes In Vivo Using a Multifunctional NIR-II Probe ADVANCED FUNCTIONAL MATERIALS Li, D., Qu, C., Liu, Q., Wu, Y., Hu, X., Qian, K., Chang, B., He, S., Yuan, Y., Li, Y., Ko, T., Yu, A., Cheng, Z. 2019
  • Editorial: Multimodality Molecular Imaging FRONTIERS IN PHYSICS Cheng, Z., Marriott, G. 2019; 7
  • NIR-II Fluorescence Endoscopy for Targeted Imaging of Colorectal Cancer. Advanced healthcare materials Suo, Y., Wu, F., Xu, P., Shi, H., Wang, T., Liu, H., Cheng, Z. 2019: e1900974


    Endoscopy is a clinical gold standard to exam the interior of a hollow organ or body cavity. For the first of time, this study presents the design and construction of a fluorescent endoscopic system that harnesses the power of the second near-infrared window II (NIR-II) fluorescence imaging. An NIR-II fluorescent molecular probe, indocyanine green (ICG) conjugated bevacizumab (Bev-ICG) that targets vascular endothelial growth factor (VEGF), is successfully synthesized and evaluated along with the NIR-II endoscopy imaging system. Simultaneous NIR-II fluorescence and white-light (WL) imaging of VEGF is validated in an orthotopic rat colorectal cancer model. This NIR-II endoscopy system is a generalizable design, and it is compatible with the most of current clinic endoscopies. Similar hardware upgrades are expected to greatly promote the application of NIR-II fluorescent imaging in the clinic.

    View details for DOI 10.1002/adhm.201900974

    View details for PubMedID 31697035

  • Evaluation of integrin alphavbeta6 cystine knot PET tracers to detect cancer and idiopathic pulmonary fibrosis. Nature communications Kimura, R. H., Wang, L., Shen, B., Huo, L., Tummers, W., Filipp, F. V., Guo, H. H., Haywood, T., Abou-Elkacem, L., Baratto, L., Habte, F., Devulapally, R., Witney, T. H., Cheng, Y., Tikole, S., Chakraborti, S., Nix, J., Bonagura, C. A., Hatami, N., Mooney, J. J., Desai, T., Turner, S., Gaster, R. S., Otte, A., Visser, B. C., Poultsides, G. A., Norton, J., Park, W., Stolowitz, M., Lau, K., Yang, E., Natarajan, A., Ilovich, O., Srinivas, S., Srinivasan, A., Paulmurugan, R., Willmann, J., Chin, F. T., Cheng, Z., Iagaru, A., Li, F., Gambhir, S. S. 2019; 10 (1): 4673


    Advances in precision molecular imaging promise to transform our ability to detect, diagnose and treat disease. Here, we describe the engineering and validation of a new cystine knot peptide (knottin) that selectively recognizes human integrin alphavbeta6 with single-digit nanomolar affinity. We solve its 3D structure by NMR and x-ray crystallography and validate leads with 3 different radiolabels in pre-clinical models of cancer. We evaluate the lead tracer's safety, biodistribution and pharmacokinetics in healthy human volunteers, and show its ability to detect multiple cancers (pancreatic, cervical and lung) in patients at two study locations. Additionally, we demonstrate that the knottin PET tracers can also detect fibrotic lung disease in idiopathic pulmonary fibrosis patients. Our results indicate that these cystine knot PET tracers may have potential utility in multiple disease states that are associated with upregulation of integrin alphavbeta6.

    View details for DOI 10.1038/s41467-019-11863-w

    View details for PubMedID 31611594

  • Multimodality Hyperpolarized C-13 MRS/PET/Multiparametric MR Imaging for Detection and Image-Guided Biopsy of Prostate Cancer: First Experience in a Canine Prostate Cancer Model MOLECULAR IMAGING AND BIOLOGY Bachawal, S. V., Park, J., Valluru, K. S., Loft, M., Felt, S. A., Vilches-Moure, J. G., Saenz, Y. F., Daniel, B., Iagaru, A., Sonn, G., Cheng, Z., Spielman, D. M., Willmann, J. K. 2019; 21 (5): 861–70
  • PET Imaging of HER2-Positive Tumors with Cu-64-Labeled Affibody Molecules MOLECULAR IMAGING AND BIOLOGY Qi, S., Hoppmann, S., Xu, Y., Cheng, Z. 2019; 21 (5): 907–16
  • A proof-of-concept application of water-soluble ytterbium(III) molecular probes in in vivo NIR-II whole body bioimaging INORGANIC CHEMISTRY FRONTIERS Ning, Y., Chen, S., Chen, H., Wang, J., He, S., Liu, Y., Cheng, Z., Zhang, J. 2019; 6 (8): 1962–67

    View details for DOI 10.1039/c9qi00157c

    View details for Web of Science ID 000479129600036

  • Quaternary Ammonium Salt Based NIR-II Probes for In Vivo Imaging ADVANCED OPTICAL MATERIALS Qu, C., Xiao, Y., Zhou, H., Ding, B., Li, A., Lin, J., Zeng, X., Chen, H., Qian, K., Zhang, X., Fang, W., Wu, J., Deng, Z., Cheng, Z., Hong, X. 2019; 7 (15)
  • Multimodality imaging of naturally active melanin nanoparticles targeting somatostatin receptor subtype 2 in human small-cell lung cancer. Nanoscale Xia, L., Guo, X., Liu, T., Xu, X., Jiang, J., Wang, F., Cheng, Z., Zhu, H., Yang, Z. 2019


    Somatostatin receptor subtype 2 (SSTR2) is highly expressed in pulmonary neuroendocrine tumors, which account for approximately 25% of all lung cancers including small-cell lung cancer (SCLC). It is possible to establish SCLC-specific imaging agents for multimodal imaging to obtain tumor integrity information. Herein, we constructed novel multifunctional organic melanin nanoparticles (MNPs) as a carrier and surface-loaded somatostatin analog octreotide to produce a human small-cell lung cancer-targeted nanoprobe OCT-PEG-MNPs. MNPs have an excellent photoacoustic imaging (PAI) function and can be directly chelated with the magnetic resonance contrast agent Mn2+, and N-bromo succinimide (NBS) can be used as an oxidant to label the nanoparticles with the long half-life radionuclide 124I by an electrophilic substitution reaction. Therefore, (124I, Mn) OCT-PEG-MNPs can not only be used for PAI but also be used for positron emission tomography (PET) and magnetic resonance imaging (MRI). The NCI-H69 SCLC tumor xenograft model with high SSTR2 expression was constructed to evaluate the multimodal imaging ability of (124I, Mn) OCT-PEG-MNPs. This nanoprobe showed good imaging abilities in PAI, MRI and PET. The PA images showed that the photoacoustic signal in the NCI-H69 tumor site gradually increased with time, and the NCI-H69 xenograft showed a clear increase in the T1-weighted signal intensity after injection of Mn-OCT-PEG-MNPs at 24 h compared to that in the prescan. MicroPET and biodistribution studies showed that the uptake of NCI-H69 tumors (8.03 ± 0.37% ID g-1) was significantly higher than that in the control A549 model (3.35 ± 0.54% ID g-1) after injection of (124I, Mn) OCT-PEG-MNPs at 24 h. The (124I, Mn) OCT-PEG-MNPs were successfully applied to multimodal imaging in a small-cell lung cancer model with high SSTR2 expression. This nanoprobe may be considered for clinical trials since it combines the numerous advantages of organic nanoparticles.

    View details for DOI 10.1039/c9nr04371c

    View details for PubMedID 31334537

  • Development of a Novel Histone Deacetylase-Targeted Near-Infrared Probe for Hepatocellular Carcinoma Imaging and Fluorescence Image-Guided Surgery. Molecular imaging and biology : MIB : the official publication of the Academy of Molecular Imaging Tang, C., Du, Y., Liang, Q., Cheng, Z., Tian, J. 2019


    PURPOSE: Hepatocellular carcinoma (HCC) is a common cancer worldwide, and complete surgical resection of diseased tissue is a reliable strategy to cure cancer. Fluorescence image-guided surgery is a promising tool for surgeons to identify and remove malignant lesions. While non-targeted fluorescent dyes have been used for HCC diagnosis and resection, insufficient specificity and false positive uptake from inflammatory tissue result in a high recurrence rate or excessive excision of healthy liver tissue. To circumvent these problems, we focused on developing novel tumor-specific targeting probe to selectively illuminate cancer region during surgery. Given overexpression of histone deacetylases (HDACs) in HCC and many other cancers, HDAC-targeted imaging has been emerged as a promising tool for tumor detection.PROCEDURES: Recently, high expression of HDACs, in particular HDAC6, has been observed in tumor samples of HCC patient, and a few HDAC inhibitors, including FDA-approved suberoylanilide hydroxamic acid (SAHA), display potent antitumor effect on HCC. Correspondingly, in this study, we utilized a small molecule SAHA with the high HDAC-binding affinity as the HCC-specific targeting ligand to develop HDAC-targeted fluorescence probe for HCC detection and fluorescence image-guided resection.RESULTS: In in vitro imaging, SAHA was labelled with fluorescein isothiocyanate (FITC) to evaluate targeting property, and the imaging results demonstrated that FITC-SAHA was specific uptake by HCC Bel-7402 cells. In in vivo imaging, near infrared fluorescence dye IRDye800CW-labelled SAHA (NIR probe IRDye800CW-SAHA) showed rapid tumor accumulation with high tumor-to-background contrast on both the subcutaneous and orthotopic HCC mouse tumor models. Furthermore, the orthotopic HCC was successfully resected by the IRDye800CW-SAHA fluorescence image-guided surgery. Moreover, IRDye800CW-SAHA showed no toxicity toward healthy tissues.CONCLUSIONS: Our results indicate that IRDye800CW-SAHA is a clinical translatable probe for HCC detection and resection.

    View details for DOI 10.1007/s11307-019-01389-4

    View details for PubMedID 31228075

  • A selenium- containing selective histone deacetylase 6 inhibitor for targeted in vivo breast tumor imaging and therapy JOURNAL OF MATERIALS CHEMISTRY B Tang, C., Du, Y., Liang, Q., Cheng, Z., Tian, J. 2019; 7 (22): 3528–36

    View details for DOI 10.1039/c9tb00383e

    View details for Web of Science ID 000472230200004

  • Enhancing Photoacoustic Intensity of Upconversion Nanoparticles by Photoswitchable Azobenzene-Containing Polymers for Dual NIR-II and Photoacoustic Imaging In Vivo ADVANCED OPTICAL MATERIALS He, S., Song, J., Liu, J., Liu, L., Qu, J., Cheng, Z. 2019; 7 (12)
  • High Affinity to Skeleton Rare Earth Doped Nanoparticles for Near-Infrared II Imaging NANO LETTERS He, S., Chen, S., Li, D., Wu, Y., Zhang, X., Liu, J., Song, J., Liu, L., Qu, J., Cheng, Z. 2019; 19 (5): 2985–92
  • Synthesis, anticancer activity and mechanism of iron chelator derived from 2,6-diacetylpyridine bis(acylhydrazones) JOURNAL OF INORGANIC BIOCHEMISTRY Yao, Q., Qi, J., Zheng, Y., Qian, K., Wei, L., Maimaitiyiming, M., Cheng, Z., Wang, Y. 2019; 193: 1–8
  • Detecting Vulnerable Atherosclerotic Plaques by Ga-68-Labeled Divalent Cystine Knot Peptide MOLECULAR PHARMACEUTICS Jiang, L., Zhu, H., Li, Y., Wu, X., Wang, H., Cheng, Z. 2019; 16 (3): 1350–57
  • Polymethine Thiopyrylium Fluorophores with Absorption beyond 1000 nm for Biological Imaging in the Second Near-Infrared Subwindow JOURNAL OF MEDICINAL CHEMISTRY Ding, B., Xiao, Y., Zhou, H., Zhang, X., Qu, C., Xu, F., Deng, Z., Cheng, Z., Hong, X. 2019; 62 (4): 2049–59


    Small-molecule fluorescence imaging in the second near-infrared (NIR-II, 1000-1700 nm) window has gained increasing interest in clinical application. Till now, very few studies have been exploited in the small-molecule fluorophores with both excitation and emission in the NIR-II window. Inspired by the indocyanine green structure, a series of polymethine dyes with both absorption and emission in the NIR-II window have been developed for NIR-II imaging, providing the feasibility to directly compare optical imaging in the NIR-IIa (1300-1400 nm) subwindow under 1064 nm excitation with that in the NIR-II window under 808 nm excitation. The signal-background ratio and the tumor-normal tissue ratio achieved great improvement under 1064 nm excitation in the imaging of mouse blood pool and U87 glioma tumors. Our study not only introduces a broadband emission fluorophore for both NIR-II and NIR-IIa imaging, but also reveals the advantages of NIR-II excitation over NIR-I in in vivo imaging.

    View details for PubMedID 30501190

  • Preparation and Preliminary Molecular Imaging Study of I-124 in-situ Labeled Organic Melanin Nanoparticles ACTA CHIMICA SINICA Xia Lei, Cheng Zhen, Zhu Hua, Yang Zhi 2019; 77 (2): 172–78

    View details for DOI 10.6023/A18090410

    View details for Web of Science ID 000466335100007

  • Controlled Nano-Bio Interface of Functional Nanoprobes for in Vivo Monitoring Enzyme Activity in Tumors ACS NANO Sun, Z., Cheng, K., Yao, Y., Wu, F., Fung, J., Chen, H., Ma, X., Tu, Y., Xing, L., Xia, L., Cheng, Z. 2019; 13 (2): 1153–67


    Engineering inorganic nanoparticles with a biocompatible shell to improve their physicochemical properties is a vital step in taking advantage of their superior magnetic, optical, and photothermal properties as multifunctional molecular imaging probes for disease diagnosis and treatment. The grafting/peeling-off strategy we developed for nanoparticle surface coating can fully control the targeting capability of functional nanoprobes by changing their colloidal behaviors such as diffusion and sedimentation rates at the desired sites. We demonstrated that a cleavable coating layer initially immobilized on the surface of magnetic resonance imaging probes not only makes the nanoparticles water-soluble but also can be selectively removed by specific enzymes, thereby resulting in a significant decrease of their water solubility in an enzyme-rich environment. Upon removal of surface coating, the changes in hydrodynamic size and surface charges of nanoprobes as a result of interacting with biomolecules and proteins lead to dramatic changes in their in vivo colloidal behaviors ( i. e., slow diffusion rates, tendency to aggregate and precipitate), which were quantitatively evaluated by examining changes in their hydrodynamic sizes, magnetic properties, and count rates during the size measurement. Because the retention time of nanoprobes within the tumor tissues depends on the uptake and excretion rate of the nanoprobes through the tumors, selective activation of nanoprobes by a specific enzyme resulted in much higher tumor accumulation and longer retention time within the tumors than that of the inactive nanoprobes, which passively passed through the tumors. The imaging contrast effect of tumors using activatable nanoprobes was significantly improved over using inactive probes. Therefore, the grafting/peeling-off strategy, as a general design approach for surface modification of nanoprobes, offers a promising and highly efficient way to render the nanoparticles suitable for targeted imaging of tumors.

    View details for DOI 10.1021/acsnano.8b05825

    View details for Web of Science ID 000460199400020

    View details for PubMedID 30673268

  • Radionuclide-Labeled Peptides for Imaging and Treatment of CXCR4-Overexpressing Malignant Tumors. Current topics in medicinal chemistry Liu, N., Wan, Q., Cheng, Z., Chen, Y. 2019


    Malignant tumors are a major cause of death. The lack of methods that provide an early diagnosis and adequate treatment of cancers is the main obstacle to precision medicine. The C-X-C chemokine receptor 4 (CXCR4) is overexpressed in various tumors and plays a key role in tumor pathogenesis. Therefore, CXCR4-targeted molecular imaging can quickly and accurately detect and quantify CXCR4 abnormalities in real time. The expression level and activation status of CXCR4 are very important for screening susceptible populations and providing an accurate diagnosis and optimal treatment. In view of the fact that radionuclide-labeled peptides have become widely used for the diagnosis and treatment of tumors, this manuscript reviews the potential of different radionuclide-labeled peptide inhibitors for the targeted imaging of CXCR4- positive tumors and targeted treatment. The article also discusses the specificity and in vivo distribution of radionuclide-labeled peptide inhibitors, and translation of these inhibitors to clinic.

    View details for PubMedID 30706786

  • PET Imaging of HER2-Positive Tumors with Cu-64-Labeled Affibody Molecules. Molecular imaging and biology : MIB : the official publication of the Academy of Molecular Imaging Qi, S., Hoppmann, S., Xu, Y., Cheng, Z. 2019


    PURPOSE: Previous studies has demonstrated the utility of human epidermal growth factor receptor type 2 (HER2) as an attractive target for cancer molecular imaging and therapy. An affibody protein with strong binding affinity for HER2, ZHER2:342, has been reported. Various methods of chelator conjugation for radiolabeling HER2 affibody molecules have been described in the literature including N-terminal conjugation, C-terminal conjugation, and other methods. Cu-64 has recently been extensively evaluated due to its half-life, decay properties, and availability. Our goal was to optimize the radiolabeling method of this affibody molecule with Cu-64, and translate a positron emission tomography (PET) probe with the best in vivo performance to clinical PET imaging of HER2-positive cancers.PROCEDURES: In our study, three anti-HER2 affibody proteins-based PET probes were prepared, and their in vivo performance was evaluated in mice bearing HER2-positive subcutaneous SKOV3 tumors. The affibody analogues, Ac-Cys-ZHER2:342, Ac-ZHER2:342(Cys39), and Ac-ZHER2:342-Cys, were synthesized using the solid phase peptide synthesis method. The purified small proteins were site-specifically conjugated with the maleimide-functionalized chelator, 1,4,7,10-tetraazacyclododecane-1,4,7-tris- aceticacid-10-maleimidethylacetamide (maleimido-mono-amide-DOTA). The resulting DOTA-affibody conjugates were then radiolabeled with Cu-64. Cell uptake assay of the resulting PET probes, [64Cu]DOTA-Cys-ZHER2:342, [64Cu]DOTA-ZHER2:342(Cys39), and [64Cu]DOTA-ZHER2:342-Cys, was performed in HER2-positive human ovarian SKOV3 carcinoma cells at 4 and 37°C. The binding affinities of the radiolabeled peptides were tested by cell saturation assay using SKOV3 cells. PET imaging, biodistribution, and metabolic stability studies were performed in mice bearing SKOV3 tumors.RESULTS: Cell uptake assays showed high and specific uptake by incubation of Cu-64-labeled affibodies with SKOV3 cells. The affinities (KD) of the PET radio probes as tested by cell saturation analysis were in the low nanomolar range with the ranking of [64Cu]DOTA-Cys-ZHER2:342 (25.2±9.2nM)[64Cu]DOTA-ZHER2:342-Cys (32.6±14.7nM)>[64Cu]DOTA-ZHER2:342(Cys39) (77.6±22.2nM). In vitro stability and in vivo metabolite analysis study revealed that all three probes were stable enough for in vivo imaging applications, while [64Cu]DOTA-Cys-ZHER2:342 showed the highest stability. In vivo small-animal PET further demonstrated fast tumor targeting, good tumor accumulation, and good tumor to normal tissue contrast of all three probes. For [64Cu]DOTA-Cys-ZHER2:342, [64Cu]DOTA-ZHER2:342(Cys39), and [64Cu]DOTA-ZHER2:342-Cys, tumor uptake at 24h are 4.0±1.0% ID/g, 4.0±0.8 %ID/g, and 4.3±0.7 %ID/g, respectively (mean ± SD, n=4). Co-injection of the probes with non-labeled anti-HER2 affibody proteins confirmed in vivo specificities of the compounds by tumor uptake reduction.CONCLUSIONS: The three Cu-64-labeled ZHER2:342 analogues all display excellent HER2 targeting ability and tumor PET imaging quality. Although varied in the position of the radiometal labeling of these three Cu-64-labeled ZHER2:342 analogues, there is no significant difference in tumor and normal tissue uptakes among the three probes. [64Cu]DOTA-Cys-ZHER2:342 stands out as the most superior PET probe because of its highest affinities and in vivo stability.

    View details for PubMedID 30617730

  • Mitochondria-targeting fluorescent molecules for high efficiency cancer growth inhibition and imaging. Chemical science Chen, H. n., Wang, J. n., Feng, X. n., Zhu, M. n., Hoffmann, S. n., Hsu, A. n., Qian, K. n., Huang, D. n., Zhao, F. n., Liu, W. n., Zhang, H. n., Cheng, Z. n. 2019; 10 (34): 7946–51


    Fluorescent mitochondria-accumulating delocalized lipophilic cations (DLCs) for cancer therapy have drawn significant attention in the field of cancer theranostics. One of the most promising fluorescent DLCs, F16, can selectively trigger the apoptosis and necrosis of cancer cells, making it an attractive targeted theranostic drug candidate. However, it suffers from low clinical translation potential, largely due to its inefficient anti-cancer activity (IC50 in the μM range) and poorly understood structure-activity relationship (SAR). In this report, eleven indole-ring substituted F16 derivatives (F16s) were synthesized. Among these derivatives, 5BMF was identified as a highly effective theranostic agent, with in vitro studies showing a low IC50 of ∼50 nM (to H2228 cells) and high cancer to normal cell selectivity index of 225. In vivo studies revealed that tumors treated with 5BMF were significantly suppressed (almost no growth over the treatment period) compared to the PBS treated control group, and also no obvious toxicity to mice was found. In addition, the tumor imaging capability of 5BMF was demonstrated by in vivo fluorescence imaging. Finally, we report for the first time a proposed SAR for F16 DLCs. Our work lays down a solid foundation for translating 5BMF into a novel and highly promising DLC for cancer theranostics.

    View details for DOI 10.1039/c9sc01410a

    View details for PubMedID 31853349

    View details for PubMedCentralID PMC6836573

  • Evaluation of a novel monoclonal antibody mAb109 by immuno-PET/fluorescent imaging for noninvasive lung adenocarcinoma diagnosis. Acta pharmacologica Sinica Zhu, H. n., Liu, T. L., Liu, C. H., Wang, J. n., Zhang, H. n., Dong, B. n., Shen, J. n., Zhao, C. K., Li, Z. F., Cheng, Z. n., Yang, Z. n. 2019


    Monoclonal antibodies are believed to be magic bullets and hold great potential for lots of biological process. About 100 μg of mAb109 was expressed in 5 × 106 cells after 10 days' immunization. 64Cu-NOTA-mAb109 was synthesized with the specific activity of 0.74 MBq/μg and high in vitro stability. The binding affinity of 64Cu-NOTA-mAb109 in A549 cells was determined to be 29.64 nM. 64Cu-NOTA-mAb109 displayed prominent tumor accumulation from 2 h to 60 h p.i. (9.34 ± 0.67 %ID/g). NIRF imaging of Cy5.5-mAb109 showed high accumulation till 9 days p.i., while tumors nearly can not be observed in negative groups, which was confirmed by autoradiography. Immunohistological study confirmed that mAb109 had strong and specific capacity to bind lung adenocarcinoma (concentration to 58 nM). Our study demonstrated mAb109 was a new platform for the development of novel agent for lung adenocarcinoma noninvasive imaging. The resulted 64Cu-NOTA-mAb109/Cy5.5-mAb109 show favorable imaging properties/specificity for A549 tumor and high sensitivity to human lung adenocarcinoma tissues.

    View details for DOI 10.1038/s41401-019-0294-9

    View details for PubMedID 31534200

  • Dysregulated integrin αVβ3 and CD47 signaling promotes joint inflammation, cartilage breakdown, and progression of osteoarthritis. JCI insight Wang, Q. n., Onuma, K. n., Liu, C. n., Wong, H. n., Bloom, M. S., Elliott, E. E., Cao, R. R., Hu, N. n., Lingampalli, N. n., Sharpe, O. n., Zhao, X. n., Sohn, D. H., Lepus, C. M., Sokolove, J. n., Mao, R. n., Cisar, C. T., Raghu, H. n., Chu, C. R., Giori, N. J., Willingham, S. B., Prohaska, S. S., Cheng, Z. n., Weissman, I. L., Robinson, W. H. 2019; 4 (18)


    Osteoarthritis (OA) is the leading cause of joint failure, yet the underlying mechanisms remain elusive, and no approved therapies that slow progression exist. Dysregulated integrin function was previously implicated in OA pathogenesis. However, the roles of integrin αVβ3 and the integrin-associated receptor CD47 in OA remain largely unknown. Here, transcriptomic and proteomic analyses of human and murine osteoarthritic tissues revealed dysregulated expression of αVβ3, CD47, and their ligands. Using genetically deficient mice and pharmacologic inhibitors, we showed that αVβ3, CD47, and the downstream signaling molecules Fyn and FAK are crucial to OA pathogenesis. MicroPET/CT imaging of a mouse model showed elevated ligand-binding capacities of integrin αVβ3 and CD47 in osteoarthritic joints. Further, our in vitro studies demonstrated that chondrocyte breakdown products, derived from articular cartilage of individuals with OA, induced αVβ3/CD47-dependent expression of inflammatory and degradative mediators, and revealed the downstream signaling network. Our findings identify a central role for dysregulated αVβ3 and CD47 signaling in OA pathogenesis and suggest that activation of αVβ3 and CD47 signaling in many articular cell types contributes to inflammation and joint destruction in OA. Thus, the data presented here provide a rationale for targeting αVβ3, CD47, and their signaling pathways as a disease-modifying therapy.

    View details for DOI 10.1172/jci.insight.128616

    View details for PubMedID 31534047

  • Mitochondria-targeted delocalized lipophilic cation complexed with human serum albumin for tumor cell imaging and treatment. Nanomedicine : nanotechnology, biology, and medicine Qian, K. n., Chen, H. n., Qu, C. n., Qi, J. n., Du, B. n., Ko, T. n., Xiang, Z. n., Kandawa-Schulz, M. n., Wang, Y. n., Cheng, Z. n. 2019: 102087


    Small molecule 5BMF is a novel mitochondria-targeted delocalized lipophilic cation (DLC) with good anti-tumor activity and fluorescence emission suitable for bioimaging. In this study, human serum albumin (HSA) complexed with 5BMF (5BMF@HSA) has been developed to further improve its solubility (from 1.61 to 5.41mg/mL), and the fluorescent intensity of 5BMF@HSA was improved over 2 times. Nearly 10-fold 5BMF was released from 5BMF@HSA complex in acidic condition when compared with neutral/basic environment. Intracellular distribution of 5BMF was altered by HSA as its signals were observed in lysosomes where free 5BMF barely localized. Both 5BMF@HSA and 5BMF showed selective toxicity toward tumor cells in μM and nM range and effectively inhibited tumor growth in mice model. In summary, 5BMF@HSA shows improved solubility in aqueous buffer and enhanced fluorescence emission, and maintains tumor inhibition capability. It is a promising protein complex for tumor cell imaging and tumor treatment.

    View details for DOI 10.1016/j.nano.2019.102087

    View details for PubMedID 31454551

  • Hierarchically Nanostructured Hybrid Platform for Tumor Delineation and Image-Guided Surgery via NIR-II Fluorescence and PET Bimodal Imaging. Small (Weinheim an der Bergstrasse, Germany) Zhang, Q. n., Zhou, H. n., Chen, H. n., Zhang, X. n., He, S. n., Ma, L. n., Qu, C. n., Fang, W. n., Han, Y. n., Wang, D. n., Huang, Y. n., Sun, Y. n., Fan, Q. n., Chen, Y. n., Cheng, Z. n. 2019: e1903382


    Bimodal imaging with fluorescence in the second near infrared window (NIR-II) and positron emission tomography (PET) has important significance for tumor diagnosis and management because of complementary advantages. It remains challenging to develop NIR-II/PET bimodal probes with high fluorescent brightness. Herein, bioinspired nanomaterials (melanin dot, mesoporous silica nanoparticle, and supported lipid bilayer), NIR-II dye CH-4T, and PET radionuclide 64 Cu are integrated into a hybrid NIR-II/PET bimodal nanoprobe. The resultant nanoprobe exhibits attractive properties such as highly uniform tunable size, effective payload encapsulation, high stability, dispersibility, and biocompatibility. Interestingly, the incorporation of CH-4T into the nanoparticle leads to 4.27-fold fluorescence enhancement, resulting in brighter NIR-II imaging for phantoms in vitro and in situ. Benefiting from the fluorescence enhancement, NIR-II imaging with the nanoprobe is carried out to precisely delineate and resect tumors. Additionally, the nanoprobe is successfully applied in tumor PET imaging, showing the accumulation of the nanoprobe in a tumor with a clear contrast from 2 to 24 h postinjection. Overall, this hierarchically nanostructured platform is able to dramatically enhance fluorescent brightness of NIR-II dye, detect tumors with NIR-II/PET imaging, and guide intraoperative resection. The NIR-II/PET bimodal nanoprobe has high potential for sensitive preoperative tumor diagnosis and precise intraoperative image-guided surgery.

    View details for DOI 10.1002/smll.201903382

    View details for PubMedID 31550084

  • Biodistribution, Radiation Dosimetry, and Clinical Application of a Melanin-Targeted PET Probe, F-18-P3BZA, in Patients JOURNAL OF NUCLEAR MEDICINE Ma, X., Wang, S., Wang, S., Liu, D., Zhao, X., Chen, H., Kang, F., Yang, W., Wang, J., Cheng, Z. 2019; 60 (1): 16–22


    N-(2-(diethylamino)-ethyl)-18F-5-fluoropicolinamide (18F-P3BZA) is a radiotracer that demonstrates high binding selectivity and affinity in melanoma. The aim of the present study was to estimate the biodistribution and clinical radiation dosimetry of 18F-P3BZA in healthy volunteers and perform a preliminary clinical application for PET/CT imaging in melanoma patients. Methods:18F-P3BZA was produced efficiently with a radiosynthesizer. Six healthy volunteers were injected with 18F-P3BZA (211.7 ± 15.4 MBq) followed by serial whole-body PET/CT scans and blood tests to assess biodistribution, pharmacokinetic, and radiation dosimetry at 10 min, 1 h, 2 h, and 4 h after injection. The vital signs of volunteers were recorded in regular intervals during the imaging sessions. The effective dose for each subject after the medical internal radiation dosimetry schema was calculated with OLINDA/EXM software. For the preliminary clinical application, 5 patients with suspected melanomas underwent 18F-P3BZA PET/CT imaging at 10 min and 1 h after injection. All patients also underwent 18F-FDG PET/CT scans on the third day to compare the potential diagnostic ability of 18F-P3BZA with 18F-FDG. Results: The radiochemistry yield of 18F-P3BZA labeling was 12.3% ± 3.9%, and the purity of 18F-P3BZA after purification and formulation was higher than 99.5%. The highest uptake of 18F-P3BZA was in the liver with an SUVmean of 8.3 ± 1.0 at 10 min after injection. The resultant whole-body effective dose was 0.0193 mSv/MBq. 18F-P3BZA showed high uptake and suggested an ability for specific imaging of melanoma and its metastasis in patients. The average SUVmean of 18F-P3BZA and 18F-FDG in tumors was 19.7 ± 5.3 and 10.8 ± 2.7 at 60 min after injection. Conclusion: Our study suggests that 18F-P3BZA is safe and compatible for clinical use. The first-in-human clinical application to melanoma showed favorable delineated tumors in patients, demonstrating the potential of 18F-P3BZA for diagnostic PET imaging of melanoma.

    View details for PubMedID 29853651

  • First-in-human liver-tumour surgery guided by multispectral fluorescence imaging in the visible and near-infrared-I/II windows. Nature biomedical engineering Hu, Z. n., Fang, C. n., Li, B. n., Zhang, Z. n., Cao, C. n., Cai, M. n., Su, S. n., Sun, X. n., Shi, X. n., Li, C. n., Zhou, T. n., Zhang, Y. n., Chi, C. n., He, P. n., Xia, X. n., Chen, Y. n., Gambhir, S. S., Cheng, Z. n., Tian, J. n. 2019


    The second near-infrared wavelength window (NIR-II, 1,000-1,700 nm) enables fluorescence imaging of tissue with enhanced contrast at depths of millimetres and at micrometre-scale resolution. However, the lack of clinically viable NIR-II equipment has hindered the clinical translation of NIR-II imaging. Here, we describe an optical-imaging instrument that integrates a visible multispectral imaging system with the detection of NIR-II and NIR-I (700-900 nm in wavelength) fluorescence (by using the dye indocyanine green) for aiding the fluorescence-guided surgical resection of primary and metastatic liver tumours in 23 patients. We found that, compared with NIR-I imaging, intraoperative NIR-II imaging provided a higher tumour-detection sensitivity (100% versus 90.6%; with 95% confidence intervals of 89.1%-100% and 75.0%-98.0%, respectively), a higher tumour-to-normal-liver-tissue signal ratio (5.33 versus 1.45) and an enhanced tumour-detection rate (56.41% versus 46.15%). We infer that combining the NIR-I/II spectral windows and suitable fluorescence probes might improve image-guided surgery in the clinic.

    View details for DOI 10.1038/s41551-019-0494-0

    View details for PubMedID 31873212

  • Structure-activity relationships of 2‑quinolinecarboxaldehyde thiosemicarbazone gallium(III) complexes with potent and selective anticancer activity. Journal of inorganic biochemistry Cao, W., Qi, J., Qian, K., Tian, L., Cheng, Z., Wang, Y. 2018; 191: 174–82


    Six gallium(III) complexes (Ga1-Ga6) with 2‑quinolinecarboxaldehyde thiosemicarbazone analogues were synthesized and characterized. These gallium(III) complexes exhibited potent anticancer activity and exceeded that of the corresponding metal free ligands. Importantly, these gallium(III) complexes have a strong selectivity for tumor cells. Through the study of cellular mechanisms, we have found that the lipophilicity of ligands is closely linked to the antitumor activity of gallium(III) complexes. Additionally, we have chosen Ga6 with the best anti-tumor activity to study the mechanism of apoptosis. Caspase-3 and 9 activation and Annexin V-FITC/Propidium iodide (PI) dual-staining studies revealed that Ga6 promote apoptosis in A549 cells lines. Ga6 induces intracellular reactive oxygen species (ROS) and disrupts mitochondrial membrane potential.

    View details for PubMedID 30530178

  • Molecular Targeted NIR-II Probe for Image-Guided Brain Tumor Surgery. Bioconjugate chemistry Kurbegovic, S., Juhl, K., Chen, H., Qu, C., Ding, B., Leth, J. M., Drzewiecki, K. T., Kjaer, A., Cheng, Z. 2018


    Optical imaging strategies for improving delineation of glioblastoma (GBM) is highly desired for guiding surgeons to distinguish cancerous tissue from healthy and precious brain tissue. Fluorescence imaging (FLI) in the second near-infrared window (NIR-II) outperforms traditional NIR-I imaging with better tissue penetration, higher spatial and temporal resolution, and less auto fluorescence and scattering. Because of high expression in GBM and many other tumors, urokinase Plasminogen Activator Receptor (uPAR) is an attractive and well proven target for FLI. Herein we aim to combine the benefit of a NIR-II fluorophore with a high affinity uPAR targeting small peptide. A targeted NIR-II fluorescent probe was developed by conjugating an in-house synthesized NIR-II fluorophore, CH1055, and a uPAR targeting peptide, AE105. To characterize the in vivo distribution and targeting properties, a dynamic imaging was performed in orthotopic GBM bearing nude mice ( n = 8). Additionally, fluorescence guided surgery of orthotopic GBM was performed in living animals. CH1055-4Glu-AE105 was easily synthesized with >75% yield and >98% HPLC evaluated purity. The retention time of the probe on analytical HPLC was 15.9 min and the product was verified by mass spectrometry. Dynamic imaging demonstrated that the uPAR targeting probe visualized orthotopic GBM through the intact skull with a tumor-to-background ratio (TBR) of 2.7 peaking at 96 h. Further, the orthotopic GBM was successfully resected in small animals guided by the NIR-II FLI. By using a small uPAR targeting NIR-II probe, FLI allows us to specifically image and detect GBM. A real-time imaging setup further renders FLI guided tumor resection, and the probe developed in this work is a promising candidate for clinical translation.

    View details for PubMedID 30296054

  • Study of Vesicular Monoamine Transporter 2 in Myopic Retina Using [F-18]FP-(+)-DTBZ MOLECULAR IMAGING AND BIOLOGY Sun, Y., Zhao, N., Liu, W., Liu, M., Ju, Z., Li, J., Cheng, Z., Liu, X. 2018; 20 (5): 771–79


    To investigate the relationship between expression level of vesicular monoamine transporter 2 (VMAT2) and myopia, as well as the feasibility of noninvasive myopia diagnosis through imaging VMAT2 in retina by using [18F]fluoropropyl-(+)-dihydrotetrabenazine ([18F]FP-(+)-DTBZ).The right eyes of ten guinea pigs were deprived of vision to establish form-deprived (FD) myopia and the left eyes were untreated as the self-control eyes. The location and expression level of VMAT2 in the eyes were detected by micro-positron emission tomography (PET)/X-ray computed tomography (CT) imaging through using [18F]FP-(+)-DTBZ. Immunofluorescence staining and Western blot were used to confirm the location and expression level of VMAT2 in the eyes. The concentrations of dopamine (DA) and its metabolites including 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were also investigated by high-performance liquid chromatography.The right eyes deprived of vision were obviously myopic (- 3.17 ± 1.33 D) after procedure, while the left eyes were hyperopic (4.60 ± 0.83 D, P < 0.0001). The main expressions of VMAT2 in the eyes were located in retina. VMAT2 was significantly reduced in the myopic retina compared to the normal one from PET/CT results (P = 0.0008), which could also be verified by Western blots (P = 0.029). The concentrations of DA, DOPAC, and HVA in the FD eyes were all significantly less than those in the control eyes (P = 0.024, P = 0.018, P = 0.008). As a role of storing and releasing DA in vesicles, VMAT2 was demonstrated positively correlating with the amounts of DA (P = 0.030), DOPAC (P = 0.038), and HVA (P = 0.025) through Pearson's correlation coefficient test.We demonstrate that [18F]FP-(+)-DTBZ can be used to noninvasively image VMAT2 in retina. The expression level of VMAT2 in retina may act as a new biomarker for myopia diagnosis. The decreasing of VMAT2 expression level may play an important role in the development of myopia through correspondingly reducing the amount of DA in retina.

    View details for PubMedID 29520623

  • A Novel Estrogen Receptor alpha-Targeted Near-Infrared Fluorescent Probe for in Vivo Detection of Breast Tumor MOLECULAR PHARMACEUTICS Tang, C., Du, Y., Liang, Q., Cheng, Z., Tian, J. 2018; 15 (10): 4702–9


    The ability to detect breast cancer early in its progression is essential to improve patient survival and quality of life. The noninvasive and dynamic imaging and functional assessments of estrogen receptor-alpha (ERα), which is commonly expressed at high levels in breast cancer, are important for effective diagnosis and treatment. Hence, the development of a specific ERα-targeted probe is a major research goal. To that end, in the present study, we created a novel near-infrared (NIR) fluorescent probe, IRDye800CW-E2, for targeted ERα imaging in breast-tumor-bearing mice. IRDye800CW-E2 consisted of a cyanine dye IRDye800CW as the NIR fluorophore and the E2 analogue ethinyl estradiol amine as an ERα targeting ligand. The ethinyl estradiol amine was initially labeled with fluorescein isothiocyanate (FITC) to evaluate the binding specificity to human breast-tumor cells in vitro. Flow chamber and in vitro confocal laser endomicroscopy imaging experiments demonstrated that FITC-E2 was specifically taken up by MCF-7 cells. Furthermore, NIR fluorescence imaging revealed the ability of IRDye800CW-E2 to rapidly target tumors and to achieve good contrast between tumors and background signal 4-48 h postinjection. The fluorescent signal of IRDye800CW-E2 in tumors was successfully blocked by the coinjection of the endogenous ERα-ligand 17β-estradiol (E2) and the probe. Ex vivo fluorescent imaging further confirmed high uptake of the probe by tumors. These results indicated that IRDye800CW-E2 has great potential as an ERα-targeted imaging probe for early breast-tumor detection and has potential for clinical translation.

    View details for PubMedID 30180594

  • Affibody-functionalized Ag2S quantum dots for photoacoustic imaging of epidermal growth factor receptor overexpressed tumors NANOSCALE Zhang, Y., Zhao, N., Qin, Y., Wu, F., Xu, Z., Lan, T., Cheng, Z., Zhao, P., Liu, H. 2018; 10 (35): 16581–90


    Photoacoustic imaging (PAI) is a new and attractive imaging modality, and it has strong potential for application in the early detection of tumors through the use of optically absorbing targeted contrast agents. Ag2S quantum dots (QD) are a promising bionanomaterial and have attracted significant attention in the field of bioimaging. In this study, water-soluble and carboxylic acid group-coated Ag2S QDs with an ultrasmall size (∼8 nm) were synthesized via a one-step method. Their surface plasmon resonance wavelength was determined to be ∼800 nm, which is ideal for PAI. Ag2S QDs were then modified with the epidermal growth factor receptor 1 (EGFR) targeted small protein affibody ZEGFR:1907. The resulted nanoprobe, ZEGFR:1907-Ag2S QDs, was then used for targeted PAI of EGFR-overexpressed tumors. The biodistribution of the nanoprobe was further measured by ex vivo near infrared fluorescence (NIRF) imaging of the dissected tissues. The PAI results showed that ZEGFR:1907-Ag2S QDs specifically image EGFR positive tumors. The biodistribution study revealed that the nanoprobe mainly accumulated in the liver, spleen and tumors; tissue H&E staining studies indicated that the probe has good biocompatibility. Overall, the affibody-functionalized Ag2S QDs are a novel targeted nanoprobe that can be used for specific PAI of tumors.

    View details for DOI 10.1039/c8nr02556h

    View details for Web of Science ID 000448419900024

    View details for PubMedID 30151510

  • Gallium(III) complexes of alpha-N-heterocyclic piperidylthiosemicarbazones: Synthesis, structure-activity relationship, cellular uptake and activation of caspases-3/7/9 Qi, J., Yao, Q., Qian, K., Tian, L., Cheng, Z., Wang, Y. ELSEVIER SCIENCE INC. 2018: 42–50


    Two types of α-N-heterocyclic piperidylthiosemicarbazone ligands and related Ga(III) complexes were synthesized. The structure of Ga4 and Ga5 were characterized by X-ray single crystal diffraction. We generated the related α-N-heterocycliperidinylthiosemicarbazone analogs to examine the effect of aldehydes or ketones in the Schiff base. The antitumor activity of both type ligands increased after coordination with gallium. Interestingly, the antitumor activity of gallium complexes containing pyridyl groups (first type ligands) is higher than that of pyrazine group-containing (second type ligands) complexes. Gallium complexes significantly depleted cellular iron, resulting in upregulation of transferrin receptor-1 and downregulation of ferritin. They also effectively activate the caspase family proteins (caspase-3/7/9), promote the release of cytochromes from the mitochondria, and ultimately lead to apoptosis.

    View details for PubMedID 29842999

  • Development of a Novel Ferrocenyl Histone Deacetylase Inhibitor for Triple-Negative Breast Cancer Therapy ORGANOMETALLICS Tang, C., Du, Y., Liang, Q., Cheng, Z., Tian, J. 2018; 37 (14): 2368–75
  • Acid-Promoted D-A-D Type Far-Red Fluorescent Probe with High Photostability for Lysosomal Nitric Oxide Imaging ANALYTICAL CHEMISTRY Wang, F., Yu, S., Xu, Z., Li, L., Dang, Y., Xu, X., Luo, Y., Cheng, Z., Yu, H., Zhang, W., Zhang, A., Ding, C. 2018; 90 (13): 7953–62


    To accurately monitor the variations of lysosomal nitric oxide (NO) under physiological condition remains a great challenge for understanding the biological function of NO. Herein, we developed a new chemotype probe, namely, MBTD, for acid-promoted and far-red fluorescence imaging of lysosomal NO in vitro and ex vivo. MBTD was rationally designed by incorporating o-phenylenediamino (OPD) moiety into the donor-acceptor-donor (D-A-D) type fluorophore based on a dual intramolecular charge transfer (ICT) mechanism. Compared to previously reported OPD-based NO probes, MBTD displays several distinct advantages including large stroke shift, huge on-off ratio with minimal autofluorescence, and high NO specificity. Particularly, MBTD exhibits an acid-promoted response to NO with high acid tolerance, which greatly improves the spatial resolution to lysosomal NO by excluding the background noise from other nonacidic organelles. Furthermore, MBTD displayed much longer-lived and more stable fluorescence emission in comparison with the commercialized NO probe. MBTD was employed for ratiometric examination of the exogenous or endogenous NO of macrophages. More importantly, MBTD was able to detect the variation of lysosomal NO level in an acute liver injury mouse model ex vivo, implying the potential of MBTD for real-time monitoring the therapeutic efficacy of drug candidates for the treatment of acute liver injury. MBTD as a novel type of NO probe might open a new avenue for precisely sensing lysosomal NO-related pathological and therapeutic process.

    View details for PubMedID 29889497

  • Synthesis, antiproliferative activity and mechanism of gallium(III)-thiosemicarbazone complexes as potential anti-breast cancer agents EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY Qi, J., Yao, Q., Qian, K., Tian, L., Cheng, Z., Yang, D., Wang, Y. 2018; 154: 91–100


    Five thiosemicarbazone ligands were synthesized and characterized by condensation with different aldehydes or ketones by 4-phenylthiosemicarbazone. The representative dichlorido[2-(Di-2-pyridinylmethylene)-Nphenylhydrazinecarbothioamide-N,N,S]-gallium(III) (Ga4) was characterized by X-ray single crystal diffraction, which was 1:1 ligand/Ga(III) complexes. The structure-activity relationship of these ligands and Ga (III) complexes have been investigated, and the results demonstrate that the formation of Ga (III) complexes have significant antiproliferative activity over the corresponding ligands. The anticancer mechanism of gallium (III) complexes has been studied in detail, which is typical agents that effect on the mitochondrial apoptotic pathway. The ability of gallium (III) complexes to inhibit the cell cycle does not enhanced with the increasing concentrations, whereas the ability to promote apoptosis is concentration-dependent.

    View details for PubMedID 29777989

  • Gallium(III)-2-benzoylpyridine-thiosemicarbazone complexes promote apoptosis through Ca2+ signaling and ROS-mediated mitochondrial pathways NEW JOURNAL OF CHEMISTRY Qi, J., Qian, K., Tian, L., Cheng, Z., Wang, Y. 2018; 42 (12): 10226–33

    View details for DOI 10.1039/c8nj00697k

    View details for Web of Science ID 000435298100098

  • Ligand-promoted ruthenium-catalyzed meta C-H chlorination of arenes using N-chloro-2,10-camphorsultam CHEMICAL COMMUNICATIONS Fan, Z., Lu, H., Cheng, Z., Zhang, A. 2018; 54 (47): 6008–11


    A practical meta C-H chlorination protocol is established via a Ru(0)-catalyzed ortho-metalation strategy. The use of N-chloro-2,10-camphorsultam as a new chlorinating agent is crucial for the success of the current reaction and an N-heterocyclic carbene (NHC) ligand could significantly enhance the reactivity of the catalytic transformation. The mechanistic studies reveal that an unusual ortho C-H ruthenation relay process with ortho chlorination of the C-Ru bond is probably involved.

    View details for DOI 10.1039/c8cc03195a

    View details for Web of Science ID 000434679500016

    View details for PubMedID 29796497

  • Crucial breakthrough of second near-infrared biological window fluorophores: design and synthesis toward multimodal imaging and theranostics. Chemical Society reviews He, S., Song, J., Qu, J., Cheng, Z. 2018


    The development of fluorophores and molecular probes for the second near-infrared biological window (NIR-II, 1000-1700 nm) represents an important, newly emerging and dynamic field in molecular imaging, chemical biology and materials chemistry. Because of reduced scattering, minimal absorption and negligible autofluorescence, NIR-II imaging provides high resolution, a high signal-to-noise ratio, and deep tissue penetration capability. Among various state-of-the-art bioimaging modalities, one of the greatest challenges in developing novel probes is to achieve both high resolution and sensitivity. The chemical design and synthesis of NIR-II fluorophores suitable for multimodal imaging is thus emerging as a new and powerful strategy for obtaining high-definition images. NIR-II fluorophores may convert NIR-II photons into heat for photothermal therapy and be excited by NIR-II light to produce singlet oxygen for photodynamic therapy. The presence of simultaneous diagnostic and therapeutic capabilities in a single probe can be used for precise treatment. In this review, we have focused on recent advances in the chemical design and synthesis of NIR-II fluorophores from small organic molecules to organic and inorganic nanoparticles, and we have further discussed recent advances and key operational differences in reported NIR-II imaging systems and biomedical applications based on NIR-II imaging, such as multimodal imaging, photothermal and photodynamic therapy, guidance for intraoperative surgery, and drug delivery.

    View details for DOI 10.1039/c8cs00234g

    View details for PubMedID 29725670

  • Synergistically Enhancing the Therapeutic Effect of Radiation Therapy with Radiation Activatable and Reactive Oxygen Species-Releasing Nanostructures ACS NANO Cheng, K., Sano, M., Jenkins, C. H., Zhang, G., Vernekohl, D., Zhao, W., Wei, C., Zhang, Y., Zhang, Z., Liu, Y., Cheng, Z., Xing, L. 2018; 12 (5): 4946–58


    Nanoparticle-based radio-sensitizers can amplify the effects of radiation therapy on tumor tissue even at relatively low concentrations while reducing the potential side effects to healthy surrounding tissues. In this study, we investigated a hybrid anisotropic nanostructure, composed of gold (Au) and titanium dioxide (TiO2), as a radio-sensitizer for radiation therapy of triple-negative breast cancer (TNBC). In contrast to other gold-based radio sensitizers, dumbbell-like Au-TiO2 nanoparticles (DATs) show a synergistic therapeutic effect on radiation therapy, mainly because of strong asymmetric electric coupling between the high atomic number metals and dielectric oxides at their interfaces. The generation of secondary electrons and reactive oxygen species (ROS) from DATs triggered by X-ray irradiation can significantly enhance the radiation effect. After endocytosed by cancer cells, DATs can generate a large amount of ROS under X-ray irradiation, eventually inducing cancer cell apoptosis. Significant tumor growth suppression and overall improvement in survival rate in a TNBC tumor model have been successfully demonstrated under DAT uptake for a radio-sensitized radiation therapy.

    View details for DOI 10.1021/acsnano.8b02038

    View details for Web of Science ID 000433404500095

    View details for PubMedID 29689158

  • Novel Cu-64 Labeled RGD(2)-BBN Heterotrimers for PET Imaging of Prostate Cancer BIOCONJUGATE CHEMISTRY Lucente, E., Liu, H., Liu, Y., Hu, X., Lacivita, E., Leopoldo, M., Cheng, Z. 2018; 29 (5): 1595–1604


    Bombesin receptor 2 (BB2) and integrin αvβ3 receptor are privileged targets for molecular imaging of cancer because of their overexpression in a number of tumor tissues. The most recent developments in heterodimer-based radiopharmaceuticals concern BB2- and integrin αvβ3-targeting compounds, consisting of bombesin (BBN) and cyclic arginine-glycine-aspartic acid peptides (RGD), connected through short length linkers. Molecular imaging probes based on RGD-BBN heterodimer design exhibit improved tumor targeting efficacy compared to the single-receptor targeting peptide monomers. However, their application in clinical study is restricted because of inefficient synthesis or unfavorable in vivo properties, which could depend on the short linker nature. Thus, the aim of the present study was to develop a RGD2-BBN heterotrimer, composed of (7-14)BBN-NH2 peptide (BBN) linked to the E[ c(RGDyK)]2 dimer peptide (RGD2), bearing the new linker type [Pro-Gly]12. The heterodimer E[c(RGDyK)]2-PEG3-Glu-(Pro-Gly)12-BBN(7-14)-NH2 (RGD2-PG12-BBN) was prepared through conventional solid phase synthesis, then conjugated with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) or 1,4,7-triazacyclononane-1-glutaric acid-4,7-diacetic acid (NODA-GA). In 64Cu labeling, the NODA-GA chelator showed superior radiochemical characteristics compared to DOTA (70% vs 40% yield, respectively). Both conjugates displayed dual targeting ability, showing good αvβ3 affinities and high BB2 receptor affinities which, in the case of the NODA-GA conjugate, were in the same range as the best RGD-BBN heterodimer ligands reported to date ( Ki = 24 nM). 64Cu-DOTA and 64Cu-NODA-GA probes were also found to be stable after 1 h incubation in mouse serum (>90%). In a microPET study in prostate cancer PC-3 xenograft mice, both probes showed low tumor uptake, probably due to poor pharmacokinetic properties in vivo. Overall, our study demonstrates that novel RGD-BBN heterodimer with long linker can be prepared and they preserve high binding affinities to BB2 and integrin αvβ3 receptor binding ability. The present study represents a step forward in the design of effective heterodimer or heterotrimer probes for dual targeting.

    View details for PubMedID 29587479

  • Dual T1 and T2 weighted magnetic resonance imaging based on Gd3+ loaded bioinspired melanin dots. Nanomedicine : nanotechnology, biology, and medicine Xu, L., Hong, S. H., Sun, Y., Sun, Z., Shou, K., Cheng, K., Chen, H., Huang, D., Xu, H., Cheng, Z. 2018


    In this report, a novel T1/T2 dual modal nanoprobe based on highly efficient and bioinspired melanin dots (M-dots) with directly loading gadolinium (Gd-M-dots) for magnetic resonance imaging (MRI) is described. In vitro and in vivo investigations have revealed that Gd-M-dots showed nontoxicity and good biocompatibilitity. Gd-M-dots relaxivity values on 3 T were determined to be r1=23.4 and r2=123.3 mM-1 s-1, which were much higher than both Gd-DTPA (r1=5.1, r2=6.2 mM-1 s-1) and Fe-M-dots (r1=1.2, r2=2.1 mM-1 s-1). For in vivo MRI, after injection of Gd-M-dots, simultaneous T1 and T2 contrast enhancement have been observed in the MRI of mice abdomen and mice bearing U87MG tumors. Furthermore, all the veins showed high signal intensity on T1-weighted MRI and remained for 2 h. Overall, in vitro and in vivo studies indicate that Gd-M-dot with high r1 relaxivity and r2 relaxivity has high potential to be a promising nanoprobe for MR venography and molecular imaging.

    View details for PubMedID 29679743

  • Diketopyrrolopyrrole-based semiconducting polymer nanoparticles for in vivo second near-infrared window imaging and image-guided tumor surgery CHEMICAL SCIENCE Shou, K., Tang, Y., Chen, H., Chen, S., Zhang, L., Zhang, A., Fan, Q., Yu, A., Cheng, Z. 2018; 9 (12): 3105–10


    A diketopyrrolopyrrole-based semiconducting polymer nanoparticle (PDFT1032) has been developed as a NIR-II (near infrared window II, 1000-1700 nm) fluorescent probe. It shows high photostability, a favorable absorption peak at 809 nm, a large Stokes shift of 223 nm, outstanding biocompatibility and minimal in vivo toxicity. More importantly, the versatile use of PDFT1032 for several important biomedical applications in the NIR-II window has been demonstrated, including the NIR-II optical imaging of tumors on a subcutaneous osteosarcoma model, assessing the vascular embolization therapy of tumors, and NIR-II image-guided orthotopic tumor surgery and sentinel lymph node biopsy (SLNB) with high spatial and temporal resolution. Overall, excellent biocompatibility, favorable hydrophilicity, and desirable chemical and optical properties make the semiconducting polymer nanoparticle PDFT1032 a highly promising NIR-II imaging probe with the potential to be widely applicable in clinical imaging and the surgical treatment of malignancy.

    View details for PubMedID 29732093

    View details for PubMedCentralID PMC5914543

  • A PET imaging approach for determining EGFR mutation status for improved lung cancer patient management SCIENCE TRANSLATIONAL MEDICINE Sun, X., Xiao, Z., Chen, G., Han, Z., Liu, Y., Zhang, C., Sun, Y., Song, Y., Wang, K., Fang, F., Wang, X., Lin, Y., Xu, L., Shao, L., Li, J., Cheng, Z., Gambhir, S., Shen, B. 2018; 10 (431)


    Tumor heterogeneity and changes in epidermal growth factor receptor (EGFR) mutation status over time challenge the design of effective EGFR tyrosine kinase inhibitor (TKI) treatment strategies for non-small cell lung cancer (NSCLC). Therefore, there is an urgent need to develop techniques for comprehensive tumor EGFR profiling in real time, particularly in lung cancer precision medicine trials. We report a positron emission tomography (PET) tracer, N-(3-chloro-4-fluorophenyl)-7-(2-(2-(2-(2-18F-fluoroethoxy) ethoxy) ethoxy) ethoxy)-6-methoxyquinazolin-4-amine (18F-MPG), with high specificity to activating EGFR mutant kinase. We evaluate the feasibility of using 18F-MPG PET for noninvasive imaging and quantification of EGFR-activating mutation status in preclinical models of NSCLC and in patients with primary and metastatic NSCLC tumors. 18F-MPG PET in NSCLC animal models showed a significant correlation (R2 = 0.9050) between 18F-MPG uptake and activating EGFR mutation status. In clinical studies with NSCLC patients (n = 75), the concordance between the detection of EGFR activation by 18F-MPG PET/computed tomography (CT) and tissue biopsy reached 84.29%. There was a greater response to EGFR-TKIs (81.58% versus 6.06%) and longer median progression-free survival (348 days versus 183 days) in NSCLC patients when 18F-MPG PET/CT SUVmax (maximum standard uptake value) was ≥2.23 versus <2.23. Our study demonstrates that 18F-MPG PET/CT is a powerful method for precise quantification of EGFR-activating mutation status in NSCLC patients, and it is a promising strategy for noninvasively identifying patients sensitive to EGFR-TKIs and for monitoring the efficacy of EGFR-TKI therapy.

    View details for PubMedID 29515002

  • Gadolinium-chelate functionalized bismuth nanotheranostic agent for in vivo MRI/CT/PAI imaging-guided photothermal cancer therapy BIOMATERIALS Wu, B., Lu, S., Yu, H., Liao, R., Li, H., Zafitatsimo, B., Li, Y., Zhang, Y., Zhu, X., Liu, H., Xu, H., Huang, S., Cheng, Z. 2018; 159: 37–47


    Multifunctional nanomaterials with simple structure and good biosafety, integrating multimodal imaging and therapeutic functions, can facilitate the development of clinical cancer treatments. Here, a simple but powerful pure bismuth based nanoparticle (Gd-PEG-Bi NPs) was developed from pure Bi NPs and gadolinium-diethylenetriaminepentaacetic acid-bis-tetradecylamide, which not only shows high quality MRI/CT/PAI triple-modal imaging, but can also be a potent photothermal therapy agent under the guidance of the triple-modal imaging. The Gd-PEG-Bi NPs showed good stability and excellent biocompatibility. In vitro and in vivo study demonstrated that Gd-PEG-Bi NPs have ultrahigh X-ray attenuation coefficient, short T1 relaxation time in MRI, and strong PAI signal. Following the imaging diagnosis, the excellent light-to-heat conversion efficiency of Gd-PEG-Bi NPs was capable of suppressing the tumor growth effectively under near-infrared laser radiation in vivo. Such multifunctional nanoparticles were ideal candidates for cancer diagnosis and treatment.

    View details for PubMedID 29309992

  • Novel dual-function near-infrared II fluorescence and PET probe for tumor delineation and image-guided surgery CHEMICAL SCIENCE Sun, Y., Zeng, X., Xiao, Y., Liu, C., Zhu, H., Zhou, H., Chen, Z., Xu, F., Wang, J., Zhu, M., Wu, J., Tian, M., Zhang, H., Deng, Z., Cheng, Z., Hong, X. 2018; 9 (8): 2092–97


    Accurate tumor identification is essential in cancer management. Incomplete excision of tumor tissue, however, negatively affects the prognosis of the patient. To accomplish radical excision of tumor tissue, radiotracers can be used that target tumor tissue and can be detected using a gamma probe during surgery. Intraoperative fluorescence imaging could allow accurate real-time tumor delineation. Herein, a novel dual-modal imaging platform using base-catalyzed double addition of thiols into a propiolamide scaffold has been developed, allowing for the highly efficient and selective assembly of various thiol units in a protecting-group-free manner. The first small-molecule based αvβ3-targeted NIR-II/PET probe 68Ga-SCH2 was concisely generated via this strategy and subsequently evaluated in mice bearing the U87MG xenograft. Excellent imaging properties such as good tumor uptake, high tumor contrast and specificity, tumor delineation and image-guided surgery were achieved in the small animal models. These attractive results of 68Ga-SCH2 allow it to be a promising αvβ3-targeted NIR-II/PET probe for clinical translation.

    View details for PubMedID 29675250

    View details for PubMedCentralID PMC5892408

  • Epitope-specific monoclonal antibodies to FSH beta increase bone mass PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Ji, Y., Liu, P., Yuen, T., Haider, S., He, J., Romero, R., Chen, H., Bloch, M., Kim, S., Lizneva, D., Munshi, L., Zhou, C., Lu, P., Iqbal, J., Cheng, Z., New, M. I., Hsueh, A. J., Bian, Z., Rosen, C. J., Sun, L., Zaidi, M. 2018; 115 (9): 2192–97
  • Pilot Study of (CuCl2)-Cu-64 for PET Imaging of Inflammation MOLECULES Jiang, L., Song, D., Chen, H., Zhang, A., Wang, H., Cheng, Z. 2018; 23 (2)
  • Macrophages as a potential tumor-microenvironment target for noninvasive imaging of early response to anticancer therapy BIOMATERIALS Cao, Q., Yan, X., Chen, K., Huang, Q., Melancon, M. P., Lopez, G., Cheng, Z., Li, C. 2018; 152: 63–76


    As a result of therapy-induced apoptosis, peripheral blood monocytes are recruited to tumors, where they become tumor-associated macrophages (TAMs). To date, few studies have investigated noninvasive molecular imaging for assessment of macrophage infiltration in response to therapy-induced apoptosis. Here, noninvasive assessment of changes in tumor accumulation of TAMs was proposed as a new way to measure early tumor response to anticancer therapy. Three different nanoparticles, QD710-Dendron quantum dots (QD710-D), Ferumoxytol, and PG-Gd-NIR813, were used for near-infrared fluorescence imaging, T2-weighted magnetic resonance imaging, and dual optical/T1-weighted MR imaging, respectively, in the MDA-MB-435 tumor model. Treatment with Abraxane induced tumor apoptosis and infiltrating macrophages. In spite of markedly different physicochemical properties among the nanoparticles, in vivo imaging revealed increased uptake of all three nanoparticles in Abraxane-treated tumors compared with untreated tumors. Moreover, imaging visualized increased uptake of QD710-D in MDA-MB-435 tumors but not in drug-resistant MDA-MB-435R tumors grown in the mice treated with Abraxane. Our results suggest that infiltration of macrophages due to chemotherapy-induced apoptosis was partially responsible for increased nanoparticle uptake in treated tumors. Noninvasive imaging techniques in conjunction with systemic administration of imageable nanoparticles that are taken up by macrophages are a potentially useful tool for assessing early treatment response.

    View details for PubMedID 29111494

    View details for PubMedCentralID PMC5693615

  • Molecular Imaging in Targeted Therapeutics CONTRAST MEDIA & MOLECULAR IMAGING Wang, Y., Cheng, Z., Liu, S., Shao, G. 2018: 3236829

    View details for PubMedID 30254550

    View details for PubMedCentralID PMC6145156

  • Multimodality Molecular Imaging of Cardiovascular Disease Based on Nanoprobes CELLULAR PHYSIOLOGY AND BIOCHEMISTRY Tu, Y., Sun, Y., Fan, Y., Cheng, Z., Yu, B. 2018; 48 (4): 1401–15


    Recently, multimodality molecular imaging has evolved into a fast-growing research field with goals of detecting and measuring biological processes in vivo non-invasively. Researchers have come to realize that the complementary abilities of different imaging modalities over single modality could provide more precisely information for the diagnosis of diseases. At present, nanoparticles-based multimodal imaging probes have received significant attention because of their ease of preparation and straightforward integration of each modality into one entity. More importantly, nanotechnology has an increasing impact on multimodality molecular imaging of cardiovascular diseases, such as atherosclerosis and vulnerable plaque, myocardial infarction, angiogenesis, apoptosis and so on. In this review, we briefly summarize that various nanoprobes are exploited for targeted molecular imaging of cardiovascular diseases, as well as associated multimodality imaging approaches and their applications in the diagnosis and treatment of cardiovascular diseases.

    View details for PubMedID 30064129

  • Synthesis, Characterization, and Biomedical Applications of a Targeted Dual-Modal Near-Infrared-II Fluorescence and Photoacoustic Imaging Nanoprobe ACS NANO Cheng, K., Chen, H., Jenkins, C. H., Zhang, G., Zhao, W., Zhang, Z., Han, F., Fung, J., Yang, M., Jiang, Y., Xing, L., Cheng, Z. 2017; 11 (12): 12276–91


    Our development of multifunctional dual-modal imaging probes aims to integrate the benefits from both second near-infrared (NIR-II) fluorescence (1000-1700 nm) and photoacoustic imaging with an ultimate goal of improving overall cancer diagnosis efficacy. Herein we designed a donor-acceptor chromophore based nanoparticle (DAP) as a dual-modal image contrast agent has strong absorption in the NIR-I window and a strong fluorescence emission peak in the NIR-II region. The dual-modal DAPs composed of D-π-A-π-D-type chromophores were PEGylated through nanoprecipitation. The multifunctional DAP surface was thus available for subsequent bioconjugation of EGFR Affibody (Ac-Cys-ZEGFR:1907) to target EGFR-positive cancers. The Affibody-conjugated DAPs appeared as highly monodisperse nanoparticles (∼30 nm) with strong absorption in the NIR-I window (at ca. 680 nm) and an extremely high fluorescence in the NIR-II region (maximum peak at 1000 nm). Consequently, the Affibody-DAPs show significantly enhanced photoacoustic and NIR-II fluorescence contrast effects in both in vitro and in vivo experiments. Moreover, the Affibody-DAPs have the capability to selectively target EGFR-positive tumors in an FTC-133 subcutaneous mouse model with relatively high photoacoustic and fluorescent signals. By taking advantage of high spatial resolution and excellent temporal resolution, photoacoustic/NIR-II fluorescence imaging with targeted dual-modal contrast agents allows us to specifically image and detect various cancers and diseases in an accurate manner.

    View details for PubMedID 29202225

  • Analysis of progress and challenges for various patterns of c-MET-targeted molecular imaging: a systematic review. EJNMMI research Han, Z., Wu, Y., Wang, K., Xiao, Y., Cheng, Z., Sun, X., Shen, B. 2017; 7 (1): 41-?


    Mesenchymal-epithelial transition factor also named c-MET is a receptor tyrosine kinase for the hepatocyte growth factor that plays a pivotal role in tumorigenesis. c-MET-targeted therapies have been tested in preclinical models and patients, with significant benefits for cancer treatment. In recent years, many studies have shown that the expression level and activation status of c-MET are closely correlated to c-MET-targeted therapy response and clinical prognosis, thus highlighting the importance of evaluating the c-MET status during and prior to targeted therapy. Molecular imaging allows the monitoring of abnormal alterations of c-MET in real time and in vivo.In this review, we initially summarize the recent advances in c-MET-targeted molecular imaging, with a special focus on the development of imaging agents ranging in size from monoclonal antibody to small molecule. The aim of this review is to report the preclinical results and clinical application of all molecular imaging studies completed until now for in vivo detection of c-MET in cancer, in order to be beneficial to development of molecular probe and the combination of molecular imaging technologies for in vivo evaluation of c-MET. Various molecular probe targeted to c-MET possesses distinctive advantages and disadvantages. For example, antibody-based probes have high binding affinity but with long metabolic cycle as well as remarkable immunogenicity.Although studies for c-MET-targeted molecular imaging have made many important advances, most of imaging agents specifically target to extracellular area of c-MET receptor; however, it is difficult to reflect entirely activation of c-MET. Therefore, small molecule probes based on tyrosine kinase inhibitors, which could target to intracellular area of c-MET without any immunogenicity, should be paid more attention.

    View details for DOI 10.1186/s13550-017-0286-z

    View details for PubMedID 28485003

  • Synthesis, crystal structure and antiproliferative mechanisms of 2-acetylpyridine-thiosemicarbazones Ga(III) with a greater selectivity against tumor cells JOURNAL OF INORGANIC BIOCHEMISTRY Qi, J., Zheng, Y., Qian, K., Tian, L., Zhang, G., Cheng, Z., Wang, Y. 2017; 177: 110–17


    Thiosemicarbazone Ga(III) complexes (C3-C5) were synthesized and characterized by X-ray single crystal diffraction, and they were all 1:1 ligand/Ga(III) complexes. The antiproliferative activity of these Ga(III) complexes was tested against three cancer cell lines, demonstrating that Ga(III) complexes showed about 3-10 folds more anticancer activity than their ligands alone. Importantly, thiosemicarbazones and Ga(III) complexes have a low toxicity to human fetal lung fibroblast cells (MRC-5) and exhibit a high therapeutic index for tumor cells. The results of UV-visible spectroscopy showed that the binding constant of C4 with Topo-I-DNA was significantly higher than that of L4. The Ga(III) complex (C4) caused Topo-I inhibition and distinct DNA cleavage. Moreover, Ga(III) complex and thiosemicarbazone ligand prolonged the G1 phase in NCI-H460 cell cycle, which might be depended on the ability of these compounds to affect the expression of cell cycle related proteins.

    View details for PubMedID 28946027

  • Novel 2-pyridinecarboxaldehyde thiosemicarbazones Ga(III) complexes with a high antiproliferative activity by promoting apoptosis and inhibiting cell cycle EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY Qi, J., Deng, J., Qian, K., Tian, L., Li, J., He, K., Huang, X., Cheng, Z., Zheng, Y., Wang, Y. 2017; 134: 34–42


    Two types of 2-pyridinecarboxaldehyde thiosemicarbazones Ga(III) complexes, which are 2:1 and 1:1 ligand/Ga(III) complexes, were synthesized and determined by X-ray single crystal diffraction. The antiproliferative activity of these Ga(III) complexes have been examined to illuminate the structure-activity relationships essential to form Ga(III) complexes with remarkable anticancer activity. In addition, Ga(III) complexes where the metal/ligand ratio was 1:1 (C4) had observably higher antiproliferative activity than 1:2 (C3). Ga(III) complexes caused a marked increase of caspase-3 and 9 activity in NCI-H460 cells compared to the metal free ligand. Caspase activation was somewhat mediated by the release of Cyt C from mitochondria after incubation with selected agents. Both types of Ga(III) complexes showed more effective in inhibition of the G1/S transition than the ligand alone.

    View details for PubMedID 28395152

  • Chelator-Free and Biocompatible Melanin Nanoplatform with Facile Loading Gadolinium and Copper-64 for Bioimaging BIOCONJUGATE CHEMISTRY Hong, S., Sun, Y., Tang, C., Cheng, K., Zhang, R., Fan, Q., Huang, D., Zhao, A., Cheng, Z. 2017; 28 (7): 1925–30


    Development of a chelator-free and biocompatible platform for the facile construction of gadolinium3+ (Gd3+)-loaded nanoparticle based probes for in vivo magentic resonance imaging (MRI) is still challenging. Herein, biocompatible Gd3+-loading melanin dots (Gd-M-dots) have been easily prepared and have exhibited good loading efficiency for Gd3+, high stability, and higher T1 relaxivity compared to the commercial Gd-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) agent. Furthermore, Gd-M-dots showed unique photoacoustic (PA) properties, and a high PA imaging signal could be observed in vivo 1 h after injection. Compared to the traditional Gd3+-loaded nanoparticles for single-modal MRI, Gd-M-dots can also be radiolabeled with 64Cu2+ for positron emission tomography. Overall, these attractive properties of Gd-M-dots render them a promising imaging agent for various biomedical applications.

    View details for PubMedID 28595014

  • Multifunctional Biomedical Imaging in Physiological and Pathological Conditions Using a NIR-II Probe ADVANCED FUNCTIONAL MATERIALS Shou, K., Qu, C., Sun, Y., Chen, H., Chen, S., Zhang, L., Xu, H., Hong, X., Yu, A., Cheng, Z. 2017; 27 (23)


    Compared with imaging in the visible (400 - 650 nm) and near-infrared window I (NIR-I, 650 - 900 nm) regions, imaging in near-infrared window II (NIR-II, 1,000-1,700 nm) is a highly promising in vivo imaging modality with improved resolution and deeper tissue penetration. In this work, a small molecule NIR-II dye,5,5'-(1H,5H-benzo[1,2-c:4,5-c'] bis[1,2,5]thiadiazole)-4,8-diyl)bis(N,N-bis(4-(3-((tert-butyldimethylsilyl)oxy)propyl)phenyl) thiophen-2-amine), has been successfully encapsulated into phospholipid vesicles to prepare a probe CQS1000. Then this novel NIR-II probe has been studied for in vivo multifunctional biological imaging. Our results indicate that the NIR-II vesicle CQS1000 can noninvasively and dynamically visualize and monitor many physiological and pathological conditions of circulatory systems, including lymphatic drainage and routing, angiogenesis of tumor and vascular deformity such as arterial thrombus formation and ischemia with high spatial and temporal resolution. More importantly, by virtue of the favorable half-life of blood circulation of CQS1000, NIR-II imaging is capable of aiding us to accomplish precise resection of tumor such as osteosarcoma, and to accelerate the process of lymph nodes dissection to complete sentinel lymph node biopsy for better decision-making during the tumor surgery. Overall, CQS1000 is a highly promising NIR-II probe for multifunctional biomedical imaging in physiological and pathological conditions, surpassing traditional NIR-I imaging modality and pathologic assessments for clinical diagnosis and treatment.

    View details for PubMedID 29623009

    View details for PubMedCentralID PMC5879786

  • Cu(I) for PET Imaging of Melanoma. Scientific reports Jiang, L., Tu, Y., Hu, X., Bao, A., Chen, H., Ma, X., Doyle, T., Shi, H., Cheng, Z. 2017; 7 (1): 2574-?


    At present, (64)Cu(II) labeled tracers including (64)CuCl2 have been widely applied in the research of molecular imaging and therapy. Human copper transporter 1 (hCTR1) is the major high affinity copper influx transporter in mammalian cells, and specially responsible for the transportation of Cu(I) not Cu(II). Thus, we investigated the feasible application of (64)Cu(I) for PET imaging. (64)Cu(II) was reduced to (64)Cu(I) with the existence of sodium L-ascorbate, DL-Dithiothreitol or cysteine. Cell uptake and efflux assay was investigated using B16F10 and A375 cell lines, respectively. Small animal PET and biodistribution studies were performed in both B16F10 and A375 tumor-bearing mice. Compared with (64)Cu(II), (64)Cu(I) exhibited higher cellular uptake by melanoma, which testified CTR1 specially influx of Cu(I). However, due to oxidation reaction in vivo, no significant difference between (64)Cu(I) and (64)Cu(II) was observed through PET images and biodistribution. Additionally, radiation absorbed doses for major tissues of human were calculated based on the mouse biodistribution. Radiodosimetry calculations for (64/67)Cu(I) and (64/67)Cu(II) were similar, which suggested that although melanoma were with high radiation absorbed doses, high radioactivity accumulation by liver and kidney should be noticed for the further application. Thus, (64)Cu(I) should be further studied to evaluate it as a PET imaging radiotracer.

    View details for DOI 10.1038/s41598-017-02691-3

    View details for PubMedID 28566692

  • A high quantum yield molecule-protein complex fluorophore for near-infrared II imaging NATURE COMMUNICATIONS Antaris, A. L., Chen, H., Diao, S., Ma, Z., Zhang, Z., Zhu, S., Wang, J., Lozano, A. X., Fan, Q., Chew, L., Zhu, M., Cheng, K., Hong, X., Dai, H., Cheng, Z. 2017; 8


    Fluorescence imaging in the second near-infrared window (NIR-II) allows visualization of deep anatomical features with an unprecedented degree of clarity. NIR-II fluorophores draw from a broad spectrum of materials spanning semiconducting nanomaterials to organic molecular dyes, yet unfortunately all water-soluble organic molecules with >1,000 nm emission suffer from low quantum yields that have limited temporal resolution and penetration depth. Here, we report tailoring the supramolecular assemblies of protein complexes with a sulfonated NIR-II organic dye (CH-4T) to produce a brilliant 110-fold increase in fluorescence, resulting in the highest quantum yield molecular fluorophore thus far. The bright molecular complex allowed for the fastest video-rate imaging in the second NIR window with ∼50-fold reduced exposure times at a fast 50 frames-per-second (FPS) capable of resolving mouse cardiac cycles. In addition, we demonstrate that the NIR-II molecular complexes are superior to clinically approved ICG for lymph node imaging deep within the mouse body.

    View details for DOI 10.1038/ncomms15269

    View details for Web of Science ID 000401626200001

    View details for PubMedID 28524850

  • Live imaging of follicle stimulating hormone receptors in gonads and bones using near infrared II fluorophore CHEMICAL SCIENCE Feng, Y., Zhu, S., Antaris, A. L., Chen, H., Xiao, Y., Lu, X., Jiang, L., Diao, S., Yu, K., Wang, Y., Herraiz, S., Yue, J., Hong, X., Hong, G., Cheng, Z., Dai, H., Hsueh, A. J. 2017; 8 (5): 3703-3711


    In vivo imaging of hormone receptors provides the opportunity to visualize target tissues under hormonal control in live animals. Detecting longer-wavelength photons in the second near-infrared window (NIR-II, 1000-1700 nm) region affords reduced photon scattering in tissues accompanied by lower autofluorescence, leading to higher spatial resolution at up to centimeter tissue penetration depths. Here, we report the conjugation of a small molecular NIR-II fluorophore CH1055 to a follicle stimulating hormone (FSH-CH) for imaging ovaries and testes in live mice. After exposure to FSH-CH, specific NIR-II signals were found in cultured ovarian granulosa cells containing FSH receptors. Injection of FSH-CH allowed live imaging of ovarian follicles and testicular seminiferous tubules in female and male adult mice, respectively. Using prepubertal mice, NIR-II signals were detected in ovaries containing only preantral follicles. Resolving earlier controversies regarding the expression of FSH receptors in cultured osteoclasts, we detected for the first time specific FSH receptor signals in bones in vivo. The present imaging of FSH receptors in live animals using a ligand-conjugated NIR-II fluorophore with low cell toxicity and rapid clearance allows the development of non-invasive molecular imaging of diverse hormonal target cells in vivo.

    View details for DOI 10.1039/c6sc04897h

    View details for Web of Science ID 000400553000048

    View details for PubMedCentralID PMC5465568

  • PSSMHCpan: a novel PSSM-based software for predicting class I peptide-HLA binding affinity. GigaScience Liu, G., Li, D., Li, Z., Qiu, S., Li, W., Chao, C., Yang, N., Li, H., Cheng, Z., Song, X., Cheng, L., Zhang, X., Wang, J., Yang, H., Ma, K., Hou, Y., Li, B. 2017; 6 (5): 1-11


    Predicting peptide binding affinity with human leukocyte antigen (HLA) is a crucial step in developing powerful antitumor vaccine for cancer immunotherapy. Currently available methods work quite well in predicting peptide binding affinity with HLA alleles such as HLA-A*0201, HLA-A*0101, and HLA-B*0702 in terms of sensitivity and specificity. However, quite a few types of HLA alleles that are present in the majority of human populations including HLA-A*0202, HLA-A*0203, HLA-A*6802, HLA-B*5101, HLA-B*5301, HLA-B*5401, and HLA-B*5701 still cannot be predicted with satisfactory accuracy using currently available methods. Furthermore, currently the most popularly used methods for predicting peptide binding affinity are inefficient in identifying neoantigens from a large quantity of whole genome and transcriptome sequencing data. Here we present a Position Specific Scoring Matrix (PSSM)-based software called PSSMHCpan to accurately and efficiently predict peptide binding affinity with a broad coverage of HLA class I alleles. We evaluated the performance of PSSMHCpan by analyzing 10-fold cross-validation on a training database containing 87 HLA alleles and obtained an average area under receiver operating characteristic curve (AUC) of 0.94 and accuracy (ACC) of 0.85. In an independent dataset (Peptide Database of Cancer Immunity) evaluation, PSSMHCpan is substantially better than the popularly used NetMHC-4.0, NetMHCpan-3.0, PickPocket, Nebula, and SMM with a sensitivity of 0.90, as compared to 0.74, 0.81, 0.77, 0.24, and 0.79. In addition, PSSMHCpan is more than 197 times faster than NetMHC-4.0, NetMHCpan-3.0, PickPocket, sNebula, and SMM when predicting neoantigens from 661 263 peptides from a breast tumor sample. Finally, we built a neoantigen prediction pipeline and identified 117 017 neoantigens from 467 cancer samples of various cancers from TCGA. PSSMHCpan is superior to the currently available methods in predicting peptide binding affinity with a broad coverage of HLA class I alleles.

    View details for DOI 10.1093/gigascience/gix017

    View details for PubMedID 28327987

  • Tumor-targeting peptides: ligands for molecular imaging and therapy. Anti-cancer agents in medicinal chemistry Zhao, N., Qin, Y., Liu, H., Cheng, Z. 2017


    The aberrant proliferation of tumor cells and abundant vasculature in tumor tissues are closely correlated with receptors that are specifically dysregulated in tumor cells. These tumor-associated targets are critical in early diagnosis and therapy selection. Ligands such as antibodies, proteins, polypeptides and polysaccharides that specifically bind to these targets can significantly improve the detection and cure rate when used as tumor imaging probes or anti-tumor agents. Compared to other targeting ligands, peptides have attracted increasingly more attention in tumor diagnostics and therapeutics because of their small sizes, high affinity, stability, ease of modification and low immunogenicity. Several peptide-based imaging probes and therapeutic agents have already been used in clinical trials. This review summarizes some of the tumor-associated targets and their corresponding peptides, as well as the potential of these peptides in cancer treatment.

    View details for DOI 10.2174/1871520617666170419143459

    View details for PubMedID 28425855

  • Diverse Applications of Nanomedicine ACS NANO Pelaz, B., Alexiou, C., Alvarez -Puebla, R. A., Alves, F., Andrews, A. M., Ashraf, S., Balogh, L. P., Ballerini, L., Bestetti, A., Brendel, C., Bosi, S., Carril, M., Chan, W. C., Chen, C., Chen, X., Chen, X., Cheng, Z., Cui, D., Du, J., Dullin, C., Escudero, A., Feliu, N., Gao, M., George, M., Gogotsi, Y., Grunweller, A., Gu, Z., Halas, N. J., Hampp, N., Hartmann, R. K., Hersam, M. C., Hunziker, P., Jian, J., Jiang, X., Jungebluth, P., Kadhiresan, P., Kataoka, K., Khademhosseini, A., Kopecek, J., Kotov, N. A., Krug, H. F., Lee, D. S., Lehr, C., Leong, K. W., Liang, X., Lim, M. L., Liz-Marzan, L. M., Ma, X., Macchiarini, P., Meng, H., Mohwald, H., Mulvaney, P., Nel, A. E., Nie, S., Nordlander, P., Okano, T., Oliveira, J., Park, T. H., Penner, R. M., Prato, M., Puntes, V., Rotello, V. M., Samarakoon, A., Schaak, R. E., Shen, Y., Sjoqvist, S., Skirtach, A. G., Soliman, M. G., Stevens, M. M., Sung, H., Tang, B. Z., Tietze, R., Udugama, B. N., VanEpps, J. S., Weil, T., Weiss, P. S., Willner, I., Wu, Y., Yang, L., Yue, Z., Zhang, Q., Zhang, Q., Zhang, X., Zhao, Y., Zhou, X., Parak, W. J. 2017; 11 (3): 2313-2381


    The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic.

    View details for DOI 10.1021/acsnano.6b06040

    View details for PubMedID 28290206

  • Effective tracking of bone mesenchymal stem cells in vivo by magnetic resonance imaging using melanin-based gadolinium(3+) nanoparticles JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A Cai, W., Wang, L., Li, S., Zhang, X., Li, T., Wang, Y., Yang, X., Xie, J., Li, J., Liu, S., Xu, W., He, S., Cheng, Z., Fan, Q., Zhang, R. 2017; 105 (1): 131-137


    Tracking transplanted stem cells is necessary to clarify cellular properties and improve transplantation success. In this study, we designed and synthesized melanin-based gadolinium(3+) (Gd(3+) )-chelate nanoparticles (MNP-Gd(3+) ) of ∼7 nm for stem cell tracking in vivo. MNP-Gd(3+) possesses many beneficial properties, such as its high stability and sensitivity, shorter T1 relaxation time, higher cell labeling efficiency, and lower cytotoxicity compared with commercial imaging agents. We found that the T1 relaxivity (r1 ) of MNP-Gd(3+) was significantly higher than that of Gd-DTPA; the nanoparticles were taken up by bone mesenchymal stem cells (BMSCs) via endocytosis and were broadly distributed in the cytoplasm. Based on an in vitro MTT assay, no cytotoxicity of labeled stem cells was observed for MNP-Gd(3+) concentrations of less than 800 µg/mL. Furthermore, we tracked MNP-Gd(3+) -labeled BMSCs in vivo using 3.0T MRI equipment. After intramuscular injection, MNP-Gd(3+) -labeled BMSCs were detected, even after four weeks, by 3T MRI. We concluded that MNP-Gd(3+) nanoparticles at appropriate concentrations can be used to effectively monitor and track BMSCs in vivo. MNP-Gd(3+) nanoparticles have potential as a new positive MRI contrast agent in clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 131-137, 2017.

    View details for DOI 10.1002/jbm.a.35891

    View details for Web of Science ID 000389145400014

  • Zwitterionic Manganese and Gadolinium Metal-Organic Frameworks as Efficient Contrast Agents for in Vivo Magnetic Resonance Imaging. ACS applied materials & interfaces Qin, L. n., Sun, Z. Y., Cheng, K. n., Liu, S. W., Pang, J. X., Xia, L. M., Chen, W. H., Cheng, Z. n., Chen, J. X. 2017; 9 (47): 41378–86


    Two water-stable three-dimensional Mn- and Gd-based metal-organic frameworks (MOFs), {[Mn2(Cmdcp)2(H2O)2]·H2O}n (1) and {[Gd(Cmdcp)(H2O)3](NO3)·3H2O}n (2, H3CmdcpBr = N-(4-carboxy benzyl)-(3,5-dicarboxyl)pyridinium bromide), have been prepared and analyzed. In vitro magnetic resonance imaging indicated that MOFs 1 and 2 possess relaxivity r1 values of 17.50 and 13.46 mM-1·S-1, respectively, which are superior to that of the control Gd-DTPA (r1 = 4.87 mM-1·S-1, DTPA = diethylene triamine pentaacetate). MOFs 1 and 2 also possessed good biocompatibility and low cytotoxicity against a model cell line. In vivo magnetic resonance images of treated Kunming mice indicated that kidneys showed remarkably positive signal enhancement after 15 min with intravenous administration of MOF 1 and the hyperintensity of both kidneys persisted for about 240 min with no obvious tissue damage. MOF 1 is therefore promising in vivo probes for imaging intravascular diseases and renal dysfunction.

    View details for PubMedID 29144731

  • In vivo biodistribution and toxicity of intravesical administration of quantum dots for optical molecular imaging of bladder cancer. Scientific reports Pan, Y. n., Chang, T. n., Marcq, G. n., Liu, C. n., Kiss, B. n., Rouse, R. n., Mach, K. E., Cheng, Z. n., Liao, J. C. 2017; 7 (1): 9309


    Optical molecular imaging holds the potential to improve cancer diagnosis. Fluorescent nanoparticles such as quantum dots (QD) offer superior optical characteristics compared to organic dyes, but their in vivo application is limited by potential toxicity from systemic administration. Topical administration provides an attractive route for targeted nanoparticles with the possibility of minimizing exposure and reduced dose. Previously, we demonstrated successful ex vivo endoscopic imaging of human bladder cancer by topical (i.e. intravesical) administration of QD-conjugated anti-CD47. Herein we investigate in vivo biodistribution and toxicity of intravesically instilled free QD and anti-CD47-QD in mice. In vivo biodistribution of anti-CD47-QD was assessed with inductively coupled plasma mass spectrometry. Local and systemic toxicity was assessed using blood tests, organ weights, and histology. On average, there was no significant accumulation of QD outside of the bladder, although in some mice we detected extravesical biodistribution of QD suggesting a route for systemic exposure under some conditions. There were no indications of acute toxicity up to 7 days after instillation. Intravesical administration of targeted nanoparticles can reduce systemic exposure, but for clinical use, nanoparticles with established biosafety profiles should be used to decrease long-term toxicity in cases where systemic exposure occurs.

    View details for PubMedID 28839158

  • Improved positron emission tomography imaging of glioblastoma cancer using novel 68Ga-labeled peptides targeting the urokinase-type plasminogen activator receptor (uPAR). Amino acids Loft, M. D., Sun, Y. n., Liu, C. n., Christensen, C. n., Huang, D. n., Kjaer, A. n., Cheng, Z. n. 2017; 49 (6): 1089–1100


    The urokinase-type plasminogen activator receptor (uPAR) is overexpressed in several cancers including glioblastoma (GBM) and is an established biomarker for metastatic potential. The uPAR-targeting peptide AE105-NH2 (Ac-Asp-Cha-Phe-(D)Ser-(D)Arg-Tyr-Leu-Trp-Ser-CONH2) is a promising candidate for non-invasive positron emission tomography (PET) imaging of uPAR. Despite the optimal physical properties of 68Ga for peptide-based PET imaging, low tumor uptakes have previously been reported using 68Ga-labeled AE105-NH2-based tracers. In an attempt to optimize the tumor uptake, we developed three novel tracers with alkane (AOC) and polyethylene glycol (PEG) spacers inserted between AE105-NH2 and the radio metal chelator 2-(4,7-bis(carboxymethyl)-1,4,7-triazonan-1-yl)pentanedioic acid (NODAGA). The resulting tracers NODAGA-AOC-AE105-NH2, NODAGA-PEG3-AE105-NH2 and NODAGA-PEG8-AE105-NH2 were compared to the non-spacer version, NODAGA-AE105-NH2. Following radiolabeling with 68Ga, we evaluated the in vitro and in vivo performance in mice bearing subcutaneous tumors derived from the uPAR-expressing human GBM cell line U87MG. In vivo PET/CT imaging showed that introduction of PEG spacers more than doubled the in vivo tumor uptake after 1 h compared with the non-spacer version: 68Ga-NODAGA-PEG3-AE105-NH2 (2.08 ± 0.37%ID/g) and 68Ga-NODAGA-PEG8-AE105-NH2 (2.01 ± 0.22%ID/g) vs. 68Ga-NODAGA-AE105-NH2 (0.70 ± 0.40%ID/g), p < 0.05. In addition, 68Ga-NODAGA-PEG8-AE105-NH2 showed significantly higher (p < 0.05) tumor-to-background contrast (3.68 ± 0.23) than the other tracers. The specific tumor-targeting property of 68Ga-NODAGA-PEG8-AE105-NH2 was established by effectively blocking the tumor uptake with co-injection of unlabeled AE105-NH2 (1 h: unblocked 2.01 ± 0.22%ID/g vs. blocked 1.24 ± 0.09%ID/g, p < 0.05). Ex vivo biodistribution confirmed the improved tumor uptakes of the PEG-modified tracers. 68Ga-NODAGA-PEG8-AE105-NH2 is thus a promising candidate for human translation for PET imaging of GBM.

    View details for PubMedID 28316028

  • Novel bright-emission small-molecule NIR-II fluorophores for in vivo tumor imaging and image-guided surgery. Chemical science Sun, Y. n., Ding, M. n., Zeng, X. n., Xiao, Y. n., Wu, H. n., Zhou, H. n., Ding, B. n., Qu, C. n., Hou, W. n., Er-Bu, A. n., Zhang, Y. n., Cheng, Z. n., Hong, X. n. 2017; 8 (5): 3489–93


    Though high brightness and biocompatible small NIR-II dyes are highly desirable in clinical or translational cancer research, their fluorescent cores are relatively limited and their synthetic processes are somewhat complicated. Herein, we have explored the design and synthesis of novel NIR-II fluorescent materials (H1) without tedious chromatographic isolation with improved fluorescence performance (QY ≈ 2%) by introducing 2-amino 9,9-dialkyl-substituted fluorene as a donor into the backbone. Several types of water-soluble and biocompatible NIR-II probes: SXH, SDH, and H1 NPs were constructed via different chemical strategies based on H1, and then their potential to be used in in vivo tumor imaging and image-guided surgery in the NIR-II region was explored. High levels of uptake were obtained for both passive and active tumor targeting probes SXH and SDH. Furthermore, high resolution imaging of blood vessels on tumors and the whole body of living mice using H1 NPs for the first time has demonstrated precise NIR-II image-guided sentinel lymph node (SLN) surgery.

    View details for PubMedID 28507722

  • Smart Self-Assembled Organic Nanoprobe for Protein-Specific Detection: Design, Synthesis, Application, and Mechanism Studies. Analytical chemistry Gao, T. n., Yang, S. n., Cao, X. n., Dong, J. n., Zhao, N. n., Ge, P. n., Zeng, W. n., Cheng, Z. n. 2017; 89 (18): 10085–93


    Specific detection or imaging protein has high potential to contribute greatly to medical diagnosis, biological research, and therapeutic applications. The level of human serum albumin (HSA) in blood is related to a variety of diseases and thus serves as an important biomarker for fast clinical diagnosis. Here we report the use of aggregation-induced emission (AIE) based supramolecular assembly to design biomolecular responsive smart organic nanomaterials for detection protein HSA. The designed nanoprobes were aggregates of small molecules and silent in fluorescence, but in the presence of HSA they disassembled and produced a clear turn-on fluorescent signal. Of a small library of nanoprobes constructed for HSA detection, structure-optical signaling and screening studies revealed that nanoprobe 7 is the most efficient one. Mechanism studies showed that nanoprobe 7 was bonded with Site I of HSA through the multiple noncovalent interactions. The resultant restriction of intramolecular rotation of nanoprobe 7 in the hydrophobic cavity of HSA induced fluorescent emission, which was validated by competitive binding assays and molecular docking. More importantly, nanoprobe 7 was successfully applied to recognize and quantify HSA in human serum samples. This study demonstrates nanoprobe 7 is a promising tool for clinical real and fast detection of HSA and thus may find many applications, and the molecular assembly based on AIE also opens a new avenue for designing smart nanomaterials for the sensitive and selective detection for varied analytes.

    View details for PubMedID 28828856

  • FRET-enabled monitoring of the thermosensitive nanoscale assembly of polymeric micelles into macroscale hydrogel and sequential cognate micelles release. Biomaterials Huang, P. n., Song, H. n., Zhang, Y. n., Liu, J. n., Cheng, Z. n., Liang, X. J., Wang, W. n., Kong, D. n., Liu, J. n. 2017; 145: 81–91


    Thermosensitive "micellar hydrogel" is prepared based on poly(ε-caprolactone-co- 1,4,8-trioxa[4.6]spiro-9-undecanone)-b-poly(ethylene glycol)- b-poly(ε-caprolactone- co-1,4,8-trioxa[4.6]spiro-9-undecanone) (PECT) triblock copolymer. Fluorescence resonance energy transfer (FRET) is adopted to explore its assembly (formation) and disassembly (degradation) mechanism within the range of 10 nm. Results prove that the thermosensitive non-covalent aggregation of micelles facilitates the hydrogel formation and the sustained shedding of cognate micelles induces the hydrogel degradation, during which polymers are steadily incorporated in micelles without any micelle disassembly or reassembly. It is confirmed that using multiple-tags based imaging technology, such as FRET imaging, the fate of macro biodegradable materials in vitro and in vivo can be followed at a precise nano even molecular level. Such an unique hydrogel composed of nothing more than PECT micelles can act as not only an injectable nanomedicine reservoir by subcutaneous or peri-tissue administration, but also an advanced "combo" macroscale platform for co-delivery of multi-modal therapeutic agents. Our findings also indicate that biological stimuli (e.g., temperature, enzymes)-induced non-covalent micelle self-assembly may provide us an effective strategy to prepare a macroscale device from nanoscale subunits.

    View details for PubMedID 28858720

  • Targeted Chemo-Photodynamic Combination Platform Based on the DOX Prodrug Nanoparticles for Enhanced Cancer Therapy. ACS applied materials & interfaces Zhang, Y. n., Huang, F. n., Ren, C. n., Yang, L. n., Liu, J. n., Cheng, Z. n., Chu, L. n., Liu, J. n. 2017; 9 (15): 13016–28


    Chemo-photodynamic combination therapy has been received widespread attention in cancer treatment due to its excellent characteristics, such as reducing the adverse side effects of chemo-drugs and improving the therapeutic effects for various cancers. In this study, RGD and DOX was conjugated to PEG by thiol-ene addition and Schiff's base reaction, respectively, to prepare the targeted and pH-sensitive antitumor prodrug nanoparticles (RGD-PEG-DOX NPs, RGD-NPs). Subsequently, the photosensitizer chlorin e6 (Ce6) was encapsulated into RGD-NPs, thus obtaining a simple and efficient chemo-photodynamic combination platform (RGD-PEG-DOX/Ce6 NPs, RGD-NPs/Ce6). This nanoparticle possessed high drug loading property of both the chemo-drug and photosensitizer and could simultaneously release them under the mild acidic microenvironment of cancer cells, which was expected to realize the synchronization therapy of chemotherapy and photodynamic therapy (PDT). Compared with free DOX and Ce6, RGD-NPs/Ce6 could significantly improve the cellular uptake capacities of DOX and Ce6, resulting in the increased contents of ROS in cancer cells and effective cytotoxicity for tumor cells (MDA-MB-231 cells and MCF-7 cells) upon a laser radiation. The in vivo experiment showed that RGD-NPs/Ce6 displayed superior tumor targeting, accumulation, and retention ability than the other groups (free DOX, free Ce6 and NPs/Ce6), and thus significantly enhancing the antitumor effect in vivo with a laser radiation. In addition, the cardiotoxicity induced by DOX was thoroughly wiped out after being loaded and delivered by the nanoparticles according to the pathological analysis. Therefore, the targeted chemo-photodynamic combination therapeutic platform may be a promising candidate for enhanced cancer therapy.

    View details for PubMedID 28378992

  • Hybrid anisotropic nanostructures for dual-modal cancer imaging and image-guided chemo-thermo therapies. Biomaterials Zhang, R., Cheng, K., Antaris, A. L., Ma, X., Yang, M., Ramakrishnan, S., Liu, G., Lu, A., Dai, H., Tian, M., Cheng, Z. 2016; 103: 265-277


    The multimodality theranostic system, which can integrate two or more different therapeutic modalities and multimodal imaging agents into a nanoentity, shows great promising prospects for the cancer treatment. Herein, we developed an efficient and novel strategy to synthesize hybrid anisotropic nanoparticles (HANs) with intrinsic multimodal theranostic capability [chemotherapy, photothermal therapy, magnetic resonance imaging (MRI), and photoacoustic imaging (PAI)]. For the first time, under the guidance of MRI and PAI, the chemotherapy and thermotherapy induced by administration of multifunctional hybrid nanoprobes were applied simultaneously to the treatment of colon cancer-bearing mice in vivo.

    View details for DOI 10.1016/j.biomaterials.2016.06.063

    View details for PubMedID 27394161

    View details for PubMedCentralID PMC4970737

  • Flexible radioluminescence imaging for FDG-guided surgery MEDICAL PHYSICS King, M. T., Jenkins, C. H., Sun, C., Carpenter, C. M., Ma, X., Cheng, K., Quynh-Thu Le, Q. T., Sunwoo, J. B., Cheng, Z., Pratx, G., Xing, L. 2016; 43 (10)


    Flexible radioluminescence imaging (Flex-RLI) is an optical method for imaging (18)F-fluorodeoxyglucose (FDG)-avid tumors. The authors hypothesize that a gadolinium oxysulfide: terbium (GOS:Tb) flexible scintillator, which loosely conforms to the body contour, can enhance tumor signal-to-background ratio (SBR) compared with RLI, which utilizes a flat scintillator. The purpose of this paper is to characterize flex-RLI with respect to alternative modalities including RLI, beta-RLI (RLI with gamma rejection), and Cerenkov luminescence imaging (CLI).The photon sensitivity, spatial resolution, and signal linearity of flex-RLI were characterized with in vitro phantoms. In vivo experiments utilizing 13 nude mice inoculated with the head and neck (UMSCC1-Luc) cell line were then conducted in accordance with the institutional Administrative Panel on Laboratory Animal Care. After intravenous injection of (18)F-FDG, the tumor SBR values for flex-RLI were compared to those for RLI, beta-RLI, and CLI using the Wilcoxon signed rank test.With respect to photon sensitivity, RLI, beta-RLI, and flex-RLI produced 1216.2, 407.0, and 98.6 times more radiance per second than CLI. Respective full-width half maximum values across a 0.5 mm capillary tube were 6.9, 6.4, 2.2, and 1.5 mm, respectively. Flex-RLI demonstrated a near perfect correlation with (18)F activity (r = 0.99). Signal uniformity for flex-RLI improved after more aggressive homogenization of the GOS powder with the silicone elastomer during formulation. In vivo, the SBR value for flex-RLI (median 1.29; interquartile range 1.18-1.36) was statistically greater than that for RLI (1.08; 1.02-1.14; p < 0.01) by 26%. However, there was no statistically significant difference in SBR values between flex-RLI and beta-RLI (p = 0.92). Furthermore, there was no statistically significant difference in SBR values between flex-RLI and CLI (p = 0.11) in a more limited dataset.Flex-RLI provides high quality images with SBRs comparable to those from CLI and beta-RLI in a single 10 s acquisition.

    View details for DOI 10.1118/1.4961745

    View details for PubMedID 27782732

  • Dual-Modality Activity-Based Probes as Molecular Imaging Agents for Vascular Inflammation JOURNAL OF NUCLEAR MEDICINE Withana, N. P., Saito, T., Ma, X., Garland, M., Liu, C., Kosuge, H., Amsallem, M., Verdoes, M., Ofori, L. O., Fischbein, M., Arakawa, M., Cheng, Z., McConnell, M. V., Bogyo, M. 2016; 57 (10): 1583-1590


    Macrophages are cellular mediators of vascular inflammation and are involved in the formation of atherosclerotic plaques. These immune cells secrete proteases such as matrix metalloproteinases and cathepsins that contribute to disease formation and progression. Here, we demonstrate that activity-based probes (ABPs) targeting cysteine cathepsins can be used in murine models of atherosclerosis to noninvasively image activated macrophage populations using both optical and PET/CT methods. The probes can also be used to topically label human carotid plaques demonstrating similar specific labeling of activated macrophage populations.Macrophage-rich carotid lesions were induced in FVB mice fed on a high-fat diet by streptozotocin injection followed by ligation of the left common carotid artery. Mice with carotid atherosclerotic plaques were injected with the optical or dual-modality probes BMV109 and BMV101, respectively, via the tail vein and noninvasively imaged by optical and small-animal PET/CT at different time points. After noninvasive imaging, the murine carotid arteries were imaged in situ and ex vivo, followed by immunofluorescence staining to confirm target labeling. Additionally, human carotid plaques were topically labeled with the probe and analyzed by both sodium dodecyl sulfate polyacrylamide gel electrophoresis and immunofluorescence staining to confirm the primary targets of the probe.Quantitative analysis of the signal intensity from both optical and PET/CT imaging showed significantly higher levels of accumulation of BMV109 and BMV101 (P < 0.005 and P < 0.05, respectively) in the ligated left carotid arteries than the right carotid or healthy arteries. Immunofluorescence staining for macrophages in cross-sectional slices of the murine artery demonstrated substantial infiltration of macrophages in the neointima and adventitia of the ligated left carotid arteries compared with the right. Analysis of the human plaque tissues by sodium dodecyl sulfate polyacrylamide gel electrophoresis confirmed that the primary targets of the probe were cathepsins X, B, S, and L. Immunofluorescence labeling of the human tissue with the probe demonstrated colocalization of the probe with CD68, elastin, and cathepsin S, similar to that observed in the experimental carotid inflammation murine model.We demonstrate that ABPs targeting the cysteine cathepsins can be used in murine models of atherosclerosis to noninvasively image activated macrophage populations using both optical and PET/CT methods. The probes could also be used to topically label human carotid plaques demonstrating similar specific labeling of activated macrophage populations. Therefore, ABPs targeting the cysteine cathepsins are potentially valuable new reagents for rapid and noninvasive imaging of atherosclerotic disease progression and plaque vulnerability.

    View details for DOI 10.2967/jnumed.115.171553

    View details for PubMedID 27199363

  • Enhanced Fructose Utilization Mediated by SLC2A5 Is a Unique Metabolic Feature of Acute Myeloid Leukemia with Therapeutic Potential. Cancer cell Chen, W., Wang, Y., Zhao, A., Xia, L., Xie, G., Su, M., Zhao, L., Liu, J., Qu, C., Wei, R., Rajani, C., Ni, Y., Cheng, Z., Chen, Z., Chen, S., Jia, W. 2016


    Rapidly proliferating leukemic progenitor cells consume substantial glucose, which may lead to glucose insufficiency in bone marrow. We show that acute myeloid leukemia (AML) cells are prone to fructose utilization with an upregulated fructose transporter GLUT5, which compensates for glucose deficiency. Notably, AML patients with upregulated transcription of the GLUT5-encoding gene SLC2A5 or increased fructose utilization have poor outcomes. Pharmacological blockage of fructose uptake ameliorates leukemic phenotypes and potentiates the cytotoxicity of the antileukemic agent, Ara-C. In conclusion, this study highlights enhanced fructose utilization as a metabolic feature of AML and a potential therapeutic target.

    View details for DOI 10.1016/j.ccell.2016.09.006

    View details for PubMedID 27746145

  • Hexametaphosphate-capped quantum dots as fluorescent probes for detection of calcium ion and fluoride SENSORS AND ACTUATORS B-CHEMICAL Liu, S., Wang, H., Cheng, Z., Liu, H. 2016; 232: 306-312
  • Preclinical Study on GRPR-Targeted Ga-68-Probes for PET Imaging of Prostate Cancer BIOCONJUGATE CHEMISTRY Sung, Y., Ma, X., Zhang, Z., Sun, Z., Loft, M., Ding, B., Liu, C., Xu, L., Yang, M., Jiang, Y., Liu, J., Xiao, Y., Cheng, Z., Hong, X. 2016; 27 (8): 1857-1864
  • Small-Protein-Stabilized Semiconductor Nanoprobe for Targeted Imaging of Cancer Cells CHEMBIOCHEM Zhao, N., Liu, S., Jiang, Q., Lan, T., Cheng, Z., Liu, H. 2016; 17 (13): 1202-1206


    Recently, semiconductor nanoparticles such as quantum dots (QDs) have attracted significant attention for bioimaging. Complex chemical functionalization, surface modification, and bioconjugation chemistry are generally required to tag biomolecules to QDs for imaging of different biomarkers. In this study, we report a simple method for production of QDs stabilized by the small protein, Affibody (AF-QDs) for fluorescent imaging of the human epidermal growth factor receptor type 2 (HER2) in human A549 lung cancer cells. This one-pot synthesis of AF-QDs avoids complex chemical conjugation procedures and demonstrates a promising approach for the preparation of fluorescent nanoprobes for imaging of cancer targets.

    View details for DOI 10.1002/cbic.201600219

    View details for Web of Science ID 000379826400003

    View details for PubMedID 27123671

  • Gold nanoparticles for cancer theranostics: A brief update JOURNAL OF INNOVATIVE OPTICAL HEALTH SCIENCES Zhao, N., Pan, Y., Cheng, Z., Liu, H. 2016; 9 (4)
  • Lasso peptide, a highly stable structure and designable multifunctional backbone AMINO ACIDS Zhao, N., Pan, Y., Cheng, Z., Liu, H. 2016; 48 (6): 1347-1356


    Lasso peptide belongs to a new class of natural product with highly compact and stable structure. It has varieties of biological activities, among which the most important one is its antibacterial efficacy. Novel lasso peptides have been constantly discovered and analyzed by advanced techniques, and the biosynthesis or even chemical synthesis of lasso peptide has been studied after learning its constituent amino acids and maturation process. Structural identification of lasso peptide provides information for elucidating the mechanisms of its antibacterial activity and basis for further modifications. Ring of lasso peptide is the key to both its highly compact and stable structure and its intrinsic antibacterial property. The loop has been considered as suitable modification region of lasso peptide, such as V11-S18 of MccJ25 being modifiable without disrupting the lasso structure in biosynthesis. The tail is the immunity protein that can export lasso peptide out of its produced strain and serve as a self-protection mechanism at the same time. Most of currently known lasso peptides are non-pathogenic, which implies that the modified lasso peptides are promising candidates for medical applications. Arginine, glycine, and aspartic acid as a ligands of cancer-specific receptor have been grafted to the loop of lasso peptide without losing its bioactivity, and many other targets are expected to be used for lasso peptide modification. Multi-molecular modification and large-scale production need to be studied and solved in future for designing and using multifunctional lasso peptide based on its extraordinary stable structure.

    View details for DOI 10.1007/s00726-016-2228-x

    View details for Web of Science ID 000376609900002

    View details for PubMedID 27074719

  • Enhanced immunotherapy of SM5-1 in hepatocellular carcinoma by conjugating with gold nanoparticles and its in vivo bioluminescence tomographic evaluation BIOMATERIALS Ma, X., Hui, H., Jin, Y., Dong, D., Liang, X., Yang, X., Tan, K., Dai, Z., Cheng, Z., Tian, J. 2016; 87: 46-56
  • 18F-FDG PET/CT of Primary Mediastinal Hepatoid Adenocarcinoma. Clinical nuclear medicine Hu, N., Tan, Y., Luo, J., Cheng, Z., Wang, Y. 2016; 41 (4): 321-322


    Hepatoid adenocarcinoma is a rare extrahepatic tumor that shows clinicopathologic and morphologic similarities to hepatocellular carcinoma. An FDG PET/CT imaging of primary mediastinal hepatoid adenocarcinoma in a 43-year-old man who had an elevated serum alpha-fetoprotein level was reported in this case. The patient's mediastinal lesion had avid FDG uptake. Hepatoid adenocarcinoma should be considered among the differential diagnoses when an FDG-avid extrahepatic mass is seen in patients with increased alpha-fetoprotein.

    View details for DOI 10.1097/RLU.0000000000001150

    View details for PubMedID 26914554

  • A small-molecule dye for NIR-II imaging NATURE MATERIALS Antaris, A. L., Chen, H., Cheng, K., Sun, Y., Hong, G., Qu, C., Diao, S., Deng, Z., Hu, X., Zhang, B., Zhang, X., Yaghi, O. K., Alamparambil, Z. R., Hong, X., Cheng, Z., Dai, H. 2016; 15 (2): 235-?


    Fluorescent imaging of biological systems in the second near-infrared window (NIR-II) can probe tissue at centimetre depths and achieve micrometre-scale resolution at depths of millimetres. Unfortunately, all current NIR-II fluorophores are excreted slowly and are largely retained within the reticuloendothelial system, making clinical translation nearly impossible. Here, we report a rapidly excreted NIR-II fluorophore (∼90% excreted through the kidneys within 24 h) based on a synthetic 970-Da organic molecule (CH1055). The fluorophore outperformed indocyanine green (ICG)-a clinically approved NIR-I dye-in resolving mouse lymphatic vasculature and sentinel lymphatic mapping near a tumour. High levels of uptake of PEGylated-CH1055 dye were observed in brain tumours in mice, suggesting that the dye was detected at a depth of ∼4 mm. The CH1055 dye also allowed targeted molecular imaging of tumours in vivo when conjugated with anti-EGFR Affibody. Moreover, a superior tumour-to-background signal ratio allowed precise image-guided tumour-removal surgery.

    View details for DOI 10.1038/NMAT4476

    View details for Web of Science ID 000368766100030

  • Isothiocyanate-Functionalized Bifunctional Chelates and fac-[M(I)(CO)3](+) (M = Re, (99m)Tc) Complexes for Targeting uPAR in Prostate Cancer. Bioconjugate chemistry Kasten, B. B., Ma, X., Cheng, K., Bu, L., Slocumb, W. S., Hayes, T. R., Trabue, S., Cheng, Z., Benny, P. D. 2016; 27 (1): 130-142


    Developing new strategies to rapidly incorporate the fac-[M(I)(CO)3](+) (M = Re, (99m)Tc) core into biological targeting vectors in radiopharmaceuticals continues to expand as molecules become more complex and as efforts to minimize nonspecific binding increase. This work examines a novel isothiocyanate-functionalized bifunctional chelate based on 2,2'-dipicolylamine (DPA) specifically designed for complexing the fac-[M(I)(CO)3](+) core. Two strategies (postlabeling and prelabeling) were explored using the isothiocyanate-functionalized DPA to determine the effectiveness of assembly on the overall yield and purity of the complex with amine containing biomolecules. A model amino acid (lysine) examined (1) amine conjugation of isothiocyanate-functionalized DPA followed by complexation with fac-[M(I)(CO)3](+) (postlabeling) and (2) complexation of fac-[M(I)(CO)3](+) with isothiocyanate-functionalized DPA followed by amine conjugation (prelabeling). Conducted with stable Re and radioactive (99m)Tc analogs, both strategies formed the product in good to excellent yields under macroscopic and radiotracer concentrations. A synthetic peptide (AE105) which targets an emerging biomarker in CaP prognosis, urokinase-type plasminogen activator receptor (uPAR), was also explored using the isothiocyanate-functionalized DPA strategy. In vitro PC-3 (uPAR+) cell uptake assays with the (99m)Tc-labeled peptide (8a) showed 4.2 ± 0.5% uptake at 4 h. In a murine model bearing PC-3 tumor xenografts, in vivo biodistribution of 8a led to favorable tumor uptake (3.7 ± 0.7% ID/g) at 4 h p.i. with relatively low accumulation (<2% ID/g) in normal organs not associated with normal peptide excretion. These results illustrate the promise of the isothiocyanate-functionalized approach for labeling amine containing biological targeting vectors with fac-[M(I)(CO)3](+).

    View details for DOI 10.1021/acs.bioconjchem.5b00531

    View details for PubMedID 26603218

  • Small Peptide and Protein-based Molecular Probes for Imaging Neurologi-cal Diseases CURRENT PROTEIN & PEPTIDE SCIENCE Venturin, G. T., Cheng, Z. 2016; 17 (6): 543-558


    Neurologic disorders are prevalent diseases in the population and represent a major cause of death and disability. Despite the advances made during recent decades, the early diagnosis of these diseases remains a challenge. Determining the pathophysiology of such disorders is also challenging and is a requirement for the development of new drugs and treatments. Molecular neuroimaging studies can help fill these gaps in knowledge by providing clinicians with the tools necessary to diagnose and monitor treatment response and by providing data to help researchers understand the mechanisms of disease. Molecular imaging is a fast-growing field of research, and the development of imaging probes is crucial to molecular imaging research. Imaging based on peptide and small protein molecular probes provides many advantages over traditional neuroimaging for the identification of many pathological aspects of nervous diseases, especially gliomas, for which this type of imaging is gradually being moved to clinical settings. Nonetheless, peptide and small protein imaging also has potential applications in other neurologic diseases such as stroke, Parkinson's disease and Alzheimer's disease. This review is focused on the main peptide and small protein probes used for molecular imaging in neurologic disease.

    View details for DOI 10.2174/1389203717666160101123500

    View details for Web of Science ID 000380779600004

    View details for PubMedID 26721406

  • Non-invasive Imaging of Idiopathic Pulmonary Fibrosis Using Cathepsin Protease Probes. Scientific reports Withana, N. P., Ma, X., McGuire, H. M., Verdoes, M., van der Linden, W. A., Ofori, L. O., Zhang, R., Li, H., Sanman, L. E., Wei, K., Yao, S., Wu, P., Li, F., Huang, H., Xu, Z., Wolters, P. J., Rosen, G. D., Collard, H. R., Zhu, Z., Cheng, Z., Bogyo, M. 2016; 6: 19755-?


    Idiopathic pulmonary fibrosis (IPF) is a lethal, chronic, progressive disease characterized by formation of scar tissue within the lungs. Because it is a disease of unknown etiology, it is difficult to diagnose, to predict disease course and to devise treatment strategies. Recent evidence suggests that activated macrophages play key roles in the pathology of IPF. Therefore, imaging probes that specifically recognize these pools of activated immune cells could provide valuable information about how these cells contribute to the pathobiology of the disease. Here we demonstrate that cysteine cathepsin-targeted imaging probes can be used to monitor the contribution of macrophages to fibrotic disease progression in the bleomycin-induced murine model of pulmonary fibrosis. Furthermore, we show that the probes highlight regions of macrophage involvement in fibrosis in human biopsy tissues from IPF patients. Finally, we present first-in-human results demonstrating non-invasive imaging of active cathepsins in fibrotic lesions of patients with IPF. Together, our findings validate small molecule cysteine cathepsin probes for clinical PET imaging and suggest that they have the potential to be used to generate mechanistically-informative molecular information regarding cellular drivers of IPF disease severity and progression.

    View details for DOI 10.1038/srep19755

    View details for PubMedID 26797565

  • Recyclable Cu(i)/melanin dots for cycloaddition, bioconjugation and cell labelling. Chemical science Sun, Y. n., Hong, S. n., Ma, X. n., Cheng, K. n., Wang, J. n., Zhang, Z. n., Yang, M. n., Jiang, Y. n., Hong, X. n., Cheng, Z. n. 2016; 7 (9): 5888–92


    Development of biocompatible and high-performance heterogeneous catalysts for bioconjugation and cell labeling is highly challenging. Melanin has previously been used as a target for melanoma imaging and therapy. Herein, this important biomarker was transferred into a novel catalytic platform. A biocompatible Cu(i)/melanin dot-based catalyst [Cu(i)/M-dots] was easily prepared and exhibited high catalytic activity and excellent reusability in various Cu(i)-catalyzed azide-alkyne cycloadditions (CuAAC). Furthermore, DNA bioconjugation was carried out efficiently using Cu(i)/M-dots under ligand-free and reductant-free conditions, and the Cu(i)/M-dots could easily be removed by centrifugation. Lastly, the integrin receptor (alkyne RGD targeted) of U87MG cells was effectively labelled with a fluorescent dye (Cyanine5.5 azide) in combination with Cu(i)/M-dots. These attractive properties of Cu(i)/M-dots render it a promising catalytic platform in bioconjugation and chemical biology applications.

    View details for PubMedID 30034730

  • Imaging of Hepatic Ectopic Pregnancy by 18F-FDG PET/CT. Clinical nuclear medicine Hao, J. n., Cheng, Z. n., Hu, N. n., Xiao, L. n., Wang, Y. n. 2016; 41 (9): 697–98


    Hepatic ectopic pregnancy is an uncommon form of extrauterine pregnancy. A 31-year-old woman had acute abdominal pain and distention. Laboratory examination showed significantly increased serum β-human chorionic gonadotropin level. Both ultrasound and MRI identified a lesion located at the right lobe of the liver. FDG PET/CT was performed to determine whether the other causes of elevated β-human chorionic gonadotropin level, which showed an oval mass with mid peripherally increased FDG activity. After surgery, pathological results confirmed a diagnosis of hepatic ectopic pregnancy.

    View details for PubMedID 27454601

  • Draft Genome Sequence of Zymomonas mobilis ZM481 (ATCC 31823). Genome announcements Zhao, N., Pan, Y., Liu, H., Cheng, Z. 2016; 4 (2)


    Zymomonas mobilisZM481 (ATCC 31823) is an ethanol-tolerant strain that can produce the highest level of ethanol inZ. mobilisfrom glucose in the shortest time. Here, we report a draft genome sequence of ZM481, which can help us understand the genes related to the ethanol tolerance of this strain.

    View details for DOI 10.1128/genomeA.00193-16

    View details for PubMedID 27056218

    View details for PubMedCentralID PMC4824251

  • FRET Imaging of Enzymatic Activities Using Smart Probes. Methods in molecular biology (Clifton, N.J.) Li, J., Zhang, Y., Cheng, Z. 2016; 1444: 37-43


    Tumor-related enzymes are extensively involved in the occurrence, development, invasion, and metastasis of tumors, indicating they hold the potential to serve as biomarkers for tumor diagnosis and treatment. Smart probes based on characteristic activities of these enzymes and fluorescence resonance energy transfer (FRET) have been widely developed for fluorescent imaging of enzymatic activities. Here, we describe the detailed chemical strategies for construction of smart probe and its application for FRET imaging of fibroblast activation protein alpha in vitro and in vivo.

    View details for DOI 10.1007/978-1-4939-3721-9_4

    View details for PubMedID 27283415

  • Robust surface coating for a fast, facile fluorine-18 labeling of iron oxide nanoparticles for PET/MR dual-modality imaging NANOSCALE Sun, Z., Cheng, K., Wu, F., Liu, H., Ma, X., Su, X., Liu, Y., Xia, L., Cheng, Z. 2016; 8 (47): 19644-19653


    Grafting a robust organic shell around inorganic nanoparticles can optimize their colloidal features to dramatically improve their physicochemical properties. Here, we have developed a polymer coating procedure for providing colloidal stability to the nanoparticles and, more importantly, for applying a fast, facile fluorine-18 labeling of iron oxide nanoparticles (IONPs) for positron emission tomography (PET)/magnetic resonance (MR) dual-modality imaging. The structure of the amphiphilic polymer is based on a backbone of polyacrylic acid, conjugated with multiple oleylamines to form a comb-like branched structure. The dense polymer shell provides high colloidal stability to the IONPs against harsh conditions such as high temperature, low pH value, and high ion strength. By incorporating a 1,4,7-triazacyclononane (NOTA) chelator to the comb-like amphiphilic polymer for the chelation of aluminum fluoride ions, we applied a one-step radiolabeling approach for a fast, facile radiofluorination of magnetic nanoparticles. The new strategy can significantly reduce the procedure time and radiation exposure. The PET/MR dual modality imaging was successfully achieved in living subjects by using (18)F labeled magnetic nanoparticles.

    View details for DOI 10.1039/c6nr07298d

    View details for Web of Science ID 000390095400019

    View details for PubMedID 27858030

    View details for PubMedCentralID PMC5154751

  • Upconversion nanocomposites for photo-based cancer theranostics JOURNAL OF MATERIALS CHEMISTRY B Wang, S., Bi, A., Zeng, W., Cheng, Z. 2016; 4 (32): 5331-5348

    View details for DOI 10.1039/c6tb00709k

    View details for Web of Science ID 000382115500001

  • Novel benzo-bis(1,2,5-thiadiazole) fluorophores for in vivo NIR-II imaging of cancer CHEMICAL SCIENCE Sun, Y., Qu, C., Chen, H., He, M., Tang, C., Shou, K., Hong, S., Yang, M., Jiang, Y., Ding, B., Xiao, Y., Xing, L., Hong, X., Cheng, Z. 2016; 7 (9): 6203-6207


    Optical imaging of diseases represents a highly dynamic and multidisciplinary research area, and second near-infrared window (NIR-II, 1000-1700 nm) imaging is at the forefront of the research on optical imaging techniques. Small-molecule based NIR-II (1000-1700 nm) dyes are highly promising candidates for in vivo molecular imaging because of their high biocompatibility, fast excretion, and high clinical translation ability. However, research reports on small-molecule based NIR-II dyes and probes are rare. Herein, we designed a series of fluorescent compounds (Q1, Q2, Q3, and Q4) and investigated the relationships between their structures and absorption/fluorescence properties. Q4 (maximum emission at 1100 nm) stood out as the dye with the best physical properties and thus was selected as a scaffold for the facile construction of two types of water-soluble and biocompatible NIR-II probes (Q4NPs and SCH1100). Highly specific gastrin-releasing peptide receptor (GRPR) targeted NIR-II imaging of prostate cancer in living mice was achieved using the small-molecule probe SCH1100, which represents the first small peptide based NIR-II probe for targeted cancer imaging. The attractive imaging properties of Q4-based NIR-II probes open up many opportunities for molecular imaging and clinical translation in the unique NIR-II window.

    View details for DOI 10.1039/c6sc01561a

    View details for Web of Science ID 000382488500072

    View details for PubMedCentralID PMC6024204

  • Nanocomposite-Based Photodynamic Therapy Strategies for Deep Tumor Treatment SMALL Hu, J., Tang, Y., Elmenoufy, A. H., Xu, H., Cheng, Z., Yang, X. 2015; 11 (44): 5860-5887
  • Dragon fruit-like biocage as an iron trapping nanoplatform for high efficiency targeted cancer multimodality imaging. Biomaterials Yang, M., Fan, Q., Zhang, R., Cheng, K., Yan, J., Pan, D., Ma, X., Lu, A., Cheng, Z. 2015; 69: 30-37


    Natural biopolymer based multifunctional nanomaterials are perfect candidates for multimodality imaging and therapeutic applications. Conventional methods of building multimodal imaging probe require either cross-linking manners to increase its in vivo stability or attach a target module to realize targeted imaging. In this study, the intrinsic photoacoustic signals and the native strong chelating properties with metal ions of melanin nanoparticle (MNP), and transferrin receptor 1 (TfR1) targeting ability of apoferritin (APF) was employed to construct an efficient nanoplatform (AMF) without tedious assembling process. Smart APF shell significantly increased metal ions loading (molar ratio of 1:800, APF/Fe(3+)) and therefore improved magnetic resonance imaging (MRI) sensitivity. Moreover, synergistic use of Fe(3+) and APF contributed to high photoacounstic imaging (PAI) sensitivity. AMF showed excellent bio-stability and presented good in vivo multimodality imaging (PET/MRI/PAI) properties (good tumor uptake, high specificity and high tumor contrast) in HT29 tumor because of its targeting property combined with the enhanced permeability and retention (EPR) effect, making it promising in theranostics and translational nanomedicine.

    View details for DOI 10.1016/j.biomaterials.2015.08.001

    View details for PubMedID 26275860

    View details for PubMedCentralID PMC4586283

  • A Self-Assembled DNA Origami-Gold Nanorod Complex for Cancer Theranostics SMALL Jiang, Q., Shi, Y., Zhang, Q., Li, N., Zhan, P., Song, L., Dai, L., Tian, J., Du, Y., Cheng, Z., Ding, B. 2015; 11 (38): 5134-5141

    View details for DOI 10.1002/smll.201501266

    View details for PubMedID 26248642

  • Biological imaging without autofluorescence in the second near-infrared region NANO RESEARCH Diao, S., Hong, G., Antaris, A. L., Blackburn, J. L., Cheng, K., Cheng, Z., Dai, H. 2015; 8 (9): 3027-3034
  • Engineering Melanin Nanoparticles as an Efficient Drug-Delivery System for Imaging-Guided Chemotherapy. Advanced materials Zhang, R., Fan, Q., Yang, M., Cheng, K., Lu, X., Zhang, L., Huang, W., Cheng, Z. 2015; 27 (34): 5063-5069

    View details for DOI 10.1002/adma.201502201

    View details for PubMedID 26222210

  • beta-Radioluminescence Imaging: A Comparative Evaluation with Cerenkov Luminescence Imaging JOURNAL OF NUCLEAR MEDICINE King, M. T., Carpenter, C. M., Sun, C., Ma, X., Quynh-Thu Le, Q. T., Sunwoo, J. B., Cheng, Z., Pratx, G., Xing, L. 2015; 56 (9): 1458-1464


    Cerenkov luminescence imaging (CLI) can provide high-resolution images of (18)F-FDG-avid tumors but requires prolonged acquisition times because of low photon sensitivity. In this study, we proposed a new modality, termed β-radioluminescence imaging (β-RLI), which incorporates a scintillator with a γ-rejection strategy for imaging β particles. We performed a comparative evaluation of β-RLI with CLI in both in vitro and in vivo systems.Using in vitro phantoms, we characterized the photon sensitivity and resolution of CLI and β-RLI. We also conducted a series of in vivo experiments with xenograft mouse models using both amelanotic (A375, UMSCC1-Luc) and melanotic (B16F10-Luc) cell lines. The B16F10 and UMSCC1 cell lines were transfected with the luciferase gene (Luc). CLI was acquired over 300 s, and β-RLI was acquired using two 10-s acquisitions. We correlated (18)F -: FDG activities, as assessed by PET, with tumor radiances for both β-RLI and CLI. We also compared tumor signal-to-background ratios (SBRs) between these modalities for amelanotic and melanotic tumors.For in vitro experiments, the photon sensitivity for β-RLI was 560-fold greater than that for CLI. However, the spatial resolution for β-RLI (4.4 mm) was inferior to that of CLI (1.0 mm). For in vivo experiments, correlations between (18)F-FDG activity and tumor radiance were 0.52 (P < 0.01) for β-RLI, 0.81 (P = 0.01) for amelanotic lesions with CLI, and -0.08 (negative contrast; P = 0.80) for melanotic lesions with CLI. Nine of 13 melanotic lesions had an SBR less than 1 for CLI, despite an SBR greater than 1 among all lesions for β-RLI.β-RLI can produce functional images of both amelanotic and melanotic tumors in a shorter time frame than CLI. Further engineering developments are needed to realize the full clinical potential of this modality.

    View details for DOI 10.2967/jnumed.115.158337

    View details for Web of Science ID 000361153000036

  • Efficient Radioisotope Energy Transfer by Gold Nanoclusters for Molecular Imaging SMALL Volotskova, O., Sun, C., Stafford, J. H., Koh, A. L., Ma, X., Cheng, Z., Cui, B., Pratx, G., Xing, L. 2015; 11 (32): 4002-4008


    Beta-emitting isotopes Fluorine-18 and Yttrium-90 are tested for their potential to stimulate gold nanoclusters conjugated with blood serum proteins (AuNCs). AuNCs excited by either medical radioisotope are found to be highly effective ionizing radiation energy transfer mediators, suitable for in vivo optical imaging. AuNCs synthesized with protein templates convert beta-decaying radioisotope energy into tissue-penetrating optical signals between 620 and 800 nm. Optical signals are not detected from AuNCs incubated with Technetium-99m, a pure gamma emitter that is used as a control. Optical emission from AuNCs is not proportional to Cerenkov radiation, indicating that the energy transfer between the radionuclide and AuNC is only partially mediated by Cerenkov photons. A direct Coulombic interaction is proposed as a novel and significant mechanism of energy transfer between decaying radionuclides and AuNCs.

    View details for DOI 10.1002/smll.201500907

    View details for Web of Science ID 000360226300016

  • Facile synthesis of near infrared fluorescent trypsin-stabilized Ag nanoclusters with tunable emission for 1,4-dihydronicotinamide adenine dinucleotide and ethanol sensing ANALYTICA CHIMICA ACTA Liu, S., Wang, H., Cheng, Z., Liu, H. 2015; 886: 151-156


    A facile chemical synthetic route was developed to prepare near-infrared fluorescent trypsin-stabilized Ag nanoclusters (Try-Ag NCs). The fluorescence emission wavelength of the produced Try-Ag NCs is tunable by simple adjusting pH value of the synthesis system, and the Try-Ag NCs offer a symmetric fluorescent excitation and emission peak. The fluorescence of Try-Ag NCs remains constant in the presence of various ions and molecules, and it can be effectively quenched by 1,4-dihydronicotinamide adenine dinucleotide (NADH) instead of its oxidized forms nicotinamide adenine dinucleotide (NAD(+)). This property enables the Try-Ag NCs to be a novel analytical platform to monitor biological reaction involved with NADH. In this work, the Try-Ag NCs was also applied to analyze ethanol based on the generation of NADH which was the product of NAD(+) and ethanol in the catalysis of alcohol dehydrogenase. And the proposed platform allowed ethanol to be determined in the range from 10 to 300 μmol/L with 5 μmol/L detection limit.

    View details for DOI 10.1016/j.aca.2015.07.001

    View details for Web of Science ID 000360643800017

  • PET imaging of insulin-like growth factor type 1 receptor expression with a Cu-64-labeled Affibody molecule AMINO ACIDS Su, X., Cheng, K., Liu, Y., Hu, X., Meng, S., Cheng, Z. 2015; 47 (7): 1409-1419


    The insulin-like growth factor 1 receptor (IGF-1R) serves as an attractive target for cancer molecular imaging and therapy. Previous single photon emission computerized tomography (SPECT) studies showed that the IGF-1R-targeting Affibody molecules (99m)Tc-ZIGF1R:4551-GGGC, [(99m)Tc(CO)3](+)-(HE)3-ZIGF1R:4551 and (111)In-DOTA-ZIGF1R:4551 can discriminate between high and low IGF-1R-expression tumors and have the potential for patient selection for IGF-1R-targeted therapy. Compared with SPECT, positron emission tomography (PET) may improve imaging of IGF-1R-expression, because of its high sensitivity, high spatial resolution, strong quantification ability. The aim of the present study was to develop the (64)Cu-labeled NOTA-conjugated Affibody molecule ZIGF-1R:4:40 as a PET probe for imaging of IGF-1R-positive tumor. An Affibody analogue (Ac-Cys-ZIGF-1R:4:40) binding to IGF-1R was site-specifically conjugated with NOTA and labeled with (64)Cu. Binding affinity and specificity of (64)Cu-NOTA-ZIGF-1R:4:40 to IGF-1R were evaluated using human glioblastoma U87MG cells. Small-animal PET, biodistribution, and metabolic stability studies were conducted on mice bearing U87MG xenografts after the injection of (64)Cu-NOTA-ZIGF-1R:4:40 with or without co-injection of unlabeled Affibody proteins. The radiosynthesis of (64)Cu-NOTA-ZIGF-1R:4:40 was completed successfully within 60 min with a decay-corrected yield of 75 %. (64)Cu-NOTA-ZIGF-1R:4:40 bound to IGF-1R with low nanomolar affinity (K D = 28.55 ± 3.95 nM) in U87MG cells. (64)Cu-NOTA-ZIGF-1R:4:40 also displayed excellent in vitro and in vivo stability. In vivo biodistribution and PET studies demonstrated targeting of U87MG gliomas xenografts was IGF-1R specific. The tumor uptake was 5.08 ± 1.07 %ID/g, and the tumor to muscle ratio was 11.89 ± 2.16 at 24 h after injection. Small animal PET imaging studies revealed that (64)Cu-NOTA-ZIGF-1R:4:40 could clearly identify U87MG tumors with good contrast at 1-24 h after injection. This study demonstrates that (64)Cu-NOTA-ZIGF-1R:4:40 is a promising PET probe for imaging IGF-1R positive tumor.

    View details for DOI 10.1007/s00726-015-1975-4

    View details for Web of Science ID 000355745900011

    View details for PubMedID 25854877

  • Cu-64-Labeled Divalent Cystine Knot Peptide for Imaging Carotid Atherosclerotic Plaques JOURNAL OF NUCLEAR MEDICINE Jiang, L., Tu, Y., Kimura, R. H., Habte, F., Chen, H., Cheng, K., Shi, H., Gambhir, S. S., Cheng, Z. 2015; 56 (6): 939-944


    The rupture of vulnerable atherosclerotic plaques that lead to stroke and myocardial infarction may be induced by macrophage infiltration and augmented by the expression of integrin αvβ3. Indeed, atherosclerotic angiogenesis may be a promising marker of inflammation. In this study, an engineered integrin αvβ3-targeting PET probe, (64)Cu-NOTA-3-4A, derived from a divalent knottin miniprotein was evaluated in a mouse model for carotid atherosclerotic plaques.Atherosclerotic plaques in BALB/C mice, maintained on a high-fat diet, were induced with streptozotocin injection and carotid artery ligation and verified by MR imaging. Knottin 3-4A was synthesized by solid-phase peptide synthesis chemistry and coupled to 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) before radiolabeling with (64)Cu. PET probe stability in mouse serum was evaluated. Mice with carotid atherosclerotic plaques were injected via the tail vein with (64)Cu-NOTA-3-4A or (18)F-FDG, followed by small-animal PET/CT imaging at different time points. Receptor targeting specificity of the probe was verified by coinjection of c(RGDyK) administered in molar excess. Subsequently, carotid artery dissection and immunofluorescence staining were performed to evaluate target expression.(64)Cu-NOTA-3-4A was synthesized in high radiochemical purity and yield and demonstrated molecular stability in both phosphate-buffered saline and mouse serum at 4 h. Small-animal PET/CT showed that (64)Cu-NOTA-3-4A accumulated at significantly higher levels in the neovasculature of carotid atherosclerotic plaques (7.41 ± 1.44 vs. 0.67 ± 0.23 percentage injected dose/gram, P < 0.05) than healthy or normal vessels at 1 h after injection. (18)F-FDG also accumulated in atherosclerotic lesions at 0.5 and 1 h after injection but at lower plaque-to-normal tissue ratios than (64)Cu-NOTA-3-4A. For example, plaque-to-normal carotid artery ratios for (18)F-FDG and (64)Cu-NOTA-3-4A at 1 h after injection were 3.75 and 14.71 (P < 0.05), respectively. Furthermore, uptake of (64)Cu-NOTA-3-4A in atherosclerotic plaques was effectively blocked (∼90% at 1 h after injection) by coinjection of c(RGDyK). Immunostaining confirmed integrin αvβ3 expression in both the infiltrating macrophages and the neovasculature of atherosclerotic plaques.(64)Cu-NOTA-3-4A demonstrates specific accumulation in carotid atherosclerotic plaques in which macrophage infiltration and angiogenesis are responsible for elevated integrin αvβ3 levels. Therefore, (64)Cu-NOTA-3-4A may demonstrate clinical utility as a PET probe for atherosclerosis imaging or for the evaluation of therapies used to treat atherosclerosis.

    View details for DOI 10.2967/jnumed.115.155176

    View details for Web of Science ID 000355570300026

    View details for PubMedID 25908832

  • Strained Cyclooctyne as a Molecular Platform for Construction of Multimodal Imaging Probes ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Sun, Y., Ma, X., Cheng, K., Wu, B., Duan, J., Chen, H., Bu, L., Zhang, R., Hu, X., Deng, Z., Xing, L., Hong, X., Cheng, Z. 2015; 54 (20): 5981-5984


    Small-molecule-based multimodal and multifunctional imaging probes play prominent roles in biomedical research and have high clinical translation ability. A novel multimodal imaging platform using base-catalyzed double addition of thiols to a strained internal alkyne such as bicyclo[6.1.0]nonyne has been established in this study, thus allowing highly selective assembly of various functional units in a protecting-group-free manner. Using this molecular platform, novel dual-modality (PET and NIRF) uPAR-targeted imaging probe: (64)Cu-CHS1 was prepared and evaluated in U87MG cells and tumor-bearing mice models. The excellent PET/NIRF imaging characteristics such as good tumor uptake (3.69%ID/g at 2 h post-injection), high tumor contrast, and specificity were achieved in the small-animal models. These attractive imaging properties make (64)Cu-CHS1 a promising probe for clinical use.

    View details for DOI 10.1002/anie.201500941

    View details for Web of Science ID 000354255400031

    View details for PubMedID 25800807

  • PET Imaging of Translocator Protein (18 kDa) in a Mouse Model of Alzheimer's Disease Using N-(2,5-Dimethoxybenzyl)-2-18F-Fluoro-N-(2-Phenoxyphenyl)Acetamide. Journal of nuclear medicine : official publication, Society of Nuclear Medicine James, M. L., Belichenko, N. P., Nguyen, T. V., Andrews, L. E., Ding, Z., Liu, H., Bodapati, D., Arksey, N., Shen, B., Cheng, Z., Wyss-Coray, T., Gambhir, S. S., Longo, F. M., Chin, F. T. 2015; 56 (2): 311-316


    Herein we aimed to evaluate the utility of N-(2,5-dimethoxybenzyl)-2-(18)F-fluoro-N-(2-phenoxyphenyl)acetamide ((18)F-PBR06) for detecting alterations in translocator protein (TSPO) (18 kDa), a biomarker of microglial activation, in a mouse model of Alzheimer's disease (AD).Wild-type (wt) and AD mice (i.e., APP(L/S)) underwent (18)F-PBR06 PET imaging at predetermined time points between the ages of 5-6 and 15-16 mo. MR images were fused with PET/CT data to quantify (18)F-PBR06 uptake in the hippocampus and cortex. Ex vivo autoradiography and TSPO/CD68 immunostaining were also performed using brain tissue from these mice.PET images showed significantly higher accumulation of (18)F-PBR06 in the cortex and hippocampus of 15- to 16-mo-old APP(L/S) mice than age-matched wts (cortex/muscle: 2.43 ± 0.19 vs. 1.55 ± 0.15, P < 0.005; hippocampus/muscle: 2.41 ± 0.13 vs. 1.55 ± 0.12, P < 0.005). And although no significant difference was found between wt and APP(L/S) mice aged 9-10 mo or less using PET (P = 0.64), we were able to visualize and quantify a significant difference in (18)F-PBR06 uptake in these mice using autoradiography (cortex/striatum: 1.13 ± 0.04 vs. 0.96 ± 0.01, P < 0.05; hippocampus/striatum: 1.266 ± 0.003 vs. 1.096 ± 0.017, P < 0.001). PET results for 15- to 16-mo-old mice correlated well with autoradiography and immunostaining (i.e., increased (18)F-PBR06 uptake in brain regions containing elevated CD68 and TSPO staining in APP(L/S) mice, compared with wts).(18)F-PBR06 shows great potential as a tool for visualizing TSPO/microglia in the progression and treatment of AD.

    View details for DOI 10.2967/jnumed.114.141648

    View details for PubMedID 25613536

  • Perylene-diimide-based nanoparticles as highly efficient photoacoustic agents for deep brain tumor imaging in living mice. Advanced materials Fan, Q., Cheng, K., Yang, Z., Zhang, R., Yang, M., Hu, X., Ma, X., Bu, L., Lu, X., Xiong, X., Huang, W., Zhao, H., Cheng, Z. 2015; 27 (5): 843-847


    In order to promote preclinical and clinical applications of photoacoustic imaging, novel photoacoustic contrast agents are highly desired for molecular imaging of diseases, especially for deep tumor imaging. Here, perylene-3,4,9,10-tetracarboxylic diiimide-based near-infrared-absorptive organic nanoparticles are reported as an efficient agent for photoacoustic imaging of deep brain tumors in living mice with enhanced permeability and retention effect.

    View details for DOI 10.1002/adma.201402972

    View details for PubMedID 25376906

    View details for PubMedCentralID PMC4347809

  • 18F-FAZA PET Imaging Response Tracks the Reoxygenation of Tumors in Mice upon Treatment with the Mitochondrial Complex I Inhibitor BAY 87-2243. Clinical cancer research Chang, E., Liu, H., Unterschemmann, K., Ellinghaus, P., Liu, S., Gekeler, V., Cheng, Z., Berndorff, D., Gambhir, S. S. 2015; 21 (2): 335-346


    We describe a noninvasive PET imaging method that monitors early therapeutic efficacy of BAY 87-2243, a novel small-molecule inhibitor of mitochondrial complex I as a function of hypoxia-inducible factor-1α (HIF1α) activity.Four PET tracers [(18)F-FDG, (18)F-Fpp(RGD)2, (18)F-FLT, and (18)F-FAZA] were assessed for uptake into tumor xenografts of drug-responsive (H460, PC3) or drug-resistant (786-0) carcinoma cells. Mice were treated with BAY 87-2243 or vehicle. At each point, RNA from treated and vehicle H460 tumor xenografts (n = 3 each) was isolated and analyzed for target genes.Significant changes in uptake of (18)F-FAZA, (18)F-FLT, and (18)F-Fpp(RGD)2 (P < 0.01) occurred with BAY 87-2243 treatment with (18)F-FAZA being the most prominent. (18)F-FDG uptake was unaffected. (18)F-FAZA tumor uptake declined by 55% to 70% (1.21% ± 0.10%ID/g to 0.35 ± 0.1%ID/g; n = 6, vehicle vs. treatment) in both H460 (P < 0.001) and PC3 (P < 0.05) xenografts 1 to 3 days after drug administration. (18)F-FAZA uptake in 786-0 xenografts was unaffected. Decline occurred before significant differences in tumor volume, thus suggesting (18)F-FAZA decrease reflected early changes in tumor metabolism. BAY 87-2243 reduced expression of hypoxia-regulated genes CA IX, ANGPTL4, and EGLN-3 by 99%, 93%, and 83%, respectively (P < 0.001 for all), which corresponds with reduced (18)F-FAZA uptake upon drug treatment. Heterogeneous expression of genes associated with glucose metabolism, vessel density, and proliferation was observed.Our studies suggest suitability of (18)F-FAZA-PET as an early pharmacodynamic monitor on the efficacy of anticancer agents that target the mitochondrial complex I and intratumor oxygen levels (e.g., BAY 87-2243). Clin Cancer Res; 21(2); 335-46. ©2014 AACR.

    View details for DOI 10.1158/1078-0432.CCR-14-0217

    View details for PubMedID 25381339

    View details for PubMedCentralID PMC4297600

  • The Advancement of Human Serum Albumin-Based Molecular Probes for Molecular Imaging CURRENT PHARMACEUTICAL DESIGN Cao, W., Lu, X., Cheng, Z. 2015; 21 (14): 1908-1915


    Human serum albumin (HSA) is an abundant protein in blood and tissue fluids and has been used as a carrier for drug delivery. HSA can improve the pharmacokinetic profiles of drugs, such as extending the blood half-life of existing drugs and reducing toxic side effects. At the same time, more and more molecular imaging probes conjugated or fused with HSA have been studied to achieve higher specificity and better pharmacokinetic performance. These molecular probes can be attached to HSA covalently or non-covalently. They can also be fused with HSA as a fusion protein or coupled with HSA in vivo. Importantly, HSA conjugated probes have been applied to many imaging modalities such as the single photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), positron emission tomography (PET) and optical imaging alone or in combination with more than one modality. Besides in vivo molecular imaging, HSA conjugated probes can be used for molecular therapeutics, image-guided therapy, such as photodynamic imaging and photodynamic therapy (PDI/PDT). Some potential problems also need to be considered when using of HSA based probe strategy which are discussed in detail in the paper. Overall, HSA based probe design represents a very useful and powerful strategy for developing more molecular probes for theranostics of diseases.

    View details for DOI 10.2174/1381612821666150302120517

    View details for Web of Science ID 000351931400013

    View details for PubMedID 25732549

  • Overexpression of miRNA-497 inhibits tumor angiogenesis by targeting VEGFR2. Scientific reports Tu, Y. n., Liu, L. n., Zhao, D. n., Liu, Y. n., Ma, X. n., Fan, Y. n., Wan, L. n., Huang, T. n., Cheng, Z. n., Shen, B. n. 2015; 5: 13827


    Recent studies reported miR-497 exhibited inhibitory effects in various cancers. However, whether miR-497 is involved in inhibiting angiogenesis, which is critical for tumor growth and metastasis, is still unknown. The purpose of this study was to investigate the potential role of miR-497 in tumor angiogenesis. In this work, cell proliferation and apoptosis analyses were conducted to explore the potential function of miR-497 in HUVECs by using MTT and TUNEL assays. Western blotting (WB) was employed to validate the downstream targets of miR-497. Furthermore, in order to disclose the role of miR-497 on angiogenesis, VEGFR2-luc transgenic mice were treated with miR-497 mimic and applied to monitor tumor angiogenesis and growth by in vivo bioluminescent imaging (BLI). The results demonstrated that overexpression of miR-497 showed inhibitory effects on VEGFR2 activation and downstream Raf/MEK/ERK signal pathways in vitro and in vivo. Moreover, overexpression of miR-497 effectively induced HUVECs apoptosis by targeting VEGFR2 and downstream PI3K/AKT signaling pathway. Furthermore, miR-497 exhibited anti-angiogenesis and anti-tumor effects in the VEGFR2-luc breast tumor model proven by BLI, WB and immunohistochemistry analysis. In summary, miR-497 inhibits tumor angiogenesis and growth via targeting VEGFR2, indicating miR-497 can be explored as a potential drug candidate for cancer therapy.

    View details for PubMedID 26345385

  • Efficient Radioisotope Energy Transfer by Gold Nanoclusters for Molecular Imaging. Small (Weinheim an der Bergstrasse, Germany) Volotskova, O. n., Sun, C. n., Stafford, J. H., Koh, A. L., Ma, X. n., Cheng, Z. n., Cui, B. n., Pratx, G. n., Xing, L. n. 2015


    Beta-emitting isotopes Fluorine-18 and Yttrium-90 are tested for their potential to stimulate gold nanoclusters conjugated with blood serum proteins (AuNCs). AuNCs excited by either medical radioisotope are found to be highly effective ionizing radiation energy transfer mediators, suitable for in vivo optical imaging. AuNCs synthesized with protein templates convert beta-decaying radioisotope energy into tissue-penetrating optical signals between 620 and 800 nm. Optical signals are not detected from AuNCs incubated with Technetium-99m, a pure gamma emitter that is used as a control. Optical emission from AuNCs is not proportional to Cerenkov radiation, indicating that the energy transfer between the radionuclide and AuNC is only partially mediated by Cerenkov photons. A direct Coulombic interaction is proposed as a novel and significant mechanism of energy transfer between decaying radionuclides and AuNCs.

    View details for PubMedID 25973916

  • FDG PET/CT in Monitoring Antituberculosis Therapy in Patient With Widespread Skeletal Tuberculosis. Clinical nuclear medicine Hu, N. n., Tan, Y. n., Cheng, Z. n., Hao, Z. n., Wang, Y. n. 2015; 40 (11): 919–21


    FDG PET/CT imaging is a useful diagnostic tool in the evaluation of both neoplastic and inflammatory lesions and has a promising role in monitoring therapeutic response. We present a 50-year-old man whose initial PET/CT scan showed multiple foci of intense FDG activity in lytic lesions in the bones. A diagnosis of skeletal tuberculosis was confirmed after bone biopsy. Follow-up FDG PET/CT performed after 12 months of regular antituberculosis treatment demonstrated complete normalization of FDG activity in the bones.

    View details for PubMedID 26284767

  • Nanocomposite-Based Photodynamic Therapy Strategies for Deep Tumor Treatment. Small (Weinheim an der Bergstrasse, Germany) Hu, J. n., Tang, Y. n., Elmenoufy, A. H., Xu, H. n., Cheng, Z. n., Yang, X. n. 2015; 11 (44): 5860–87


    Photodynamic therapy (PDT), as an emerging clinically approved modality, has been used for treatment of various cancer diseases. Conventional PDT strategies are mainly focused on superficial lesions because the wavelength of illumination light of most clinically approved photosensitizers (PSs) is located in the UV/VIS range that possesses limited tissue penetration ability, leading to ineffective therapeutic response for deep-seated tumors. The combination of PDT and nanotechnology is becoming a promising approach to fight against deep tumors. Here, the rapid development of new PDT modalities based on various smartly designed nanocomposites integrating with conventionally used PSs for deep tumor treatments is introduced. Until now many types of multifunctional nanoparticles have been studied, and according to the source of excitation energy they can be classified into three major groups: near infrared (NIR) light excited nanomaterials, X-ray excited scintillating/afterglow nanoparticles, and internal light emission excited nanocarriers. The in vitro and in vivo applications of these newly developed PDT modalities are further summarized here, which highlights their potential use as promising nano-agents for deep tumor therapy.

    View details for PubMedID 26398119

  • Amino-functionalized green fluorescent carbon dots as surface energy transfer biosensors for hyaluronidase NANOSCALE Liu, S., Zhao, N., Cheng, Z., Liu, H. 2015; 7 (15): 6836-6842


    Amino-functionalized fluorescent carbon dots have been prepared by hydrothermal treatment of glucosamine with excess pyrophosphate. The produced carbon dots showed stabilized green emission fluorescence at various excitation wavelengths and pH environments. Herein, we demonstrate the surface energy transfer between the amino-functionalized carbon dots and negatively charged hyaluronate stabilized gold nanoparticles. Hyaluronidase can degrade hyaluronate and break down the hyaluronate stabilized gold nanoparticles to inhibit the surface energy transfer. The developed fluorescent carbon dot/gold nanoparticle system can be utilized as a biosensor for sensitive and selective detection of hyaluronidase by two modes which include fluorescence measurements and colorimetric analysis.

    View details for DOI 10.1039/c5nr00070j

    View details for Web of Science ID 000352277500053

    View details for PubMedID 25807038

  • Extracellular Matrix can Recover the Downregulation of Adhesion Molecules after Cell Detachment and Enhance Endothelial Cell Engraftment. Scientific reports He, N., Xu, Y., Du, W., Qi, X., Liang, L., Wang, Y., Feng, G., Fan, Y., Han, Z., Kong, D., Cheng, Z., Wu, J. C., He, Z., Li, Z. 2015; 5: 10902-?


    The low cell engraftment after transplantation limits the successful application of stem cell therapy and the exact pathway leading to acute donor cell death following transplantation is still unknown. Here we investigated if processes involved in cell preparation could initiate downregulation of adhesion-related survival signals, and further affect cell engraftment after transplantation. Human embryonic stem cell-derived endothelial cells (hESC-ECs) were suspended in PBS or Matrigel and kept at 4 °C. Quantitative RT-PCR analysis was used to test the adhesion and apoptosis genes' expression of hESC-ECs. We demonstrated that cell detachment can cause downregulation of cell adhesion and extracellular matrix (ECM) molecules, but no obvious cell anoikis, a form of apoptosis after cell detachment, was observed. The downregulation of adhesion and ECM molecules could be regained in the presence of Matrigel. Finally, we transplanted hESC-ECs into a mouse myocardial ischemia model. When transplanted with Matrigel, the long-term engraftment of hESC-ECs was increased through promoting angiogenesis and inhibiting apoptosis, and this was confirmed by bioluminescence imaging. In conclusion, ECM could rescue the functional genes expression after cell detached from culture dish, and this finding highlights the importance of increasing stem cell engraftment by mimicking stem cell niches through ECM application.

    View details for DOI 10.1038/srep10902

    View details for PubMedID 26039874

    View details for PubMedCentralID PMC4454140

  • Pd-catalyzed alpha-selective C(sp(3))-H acetoxylation of amides through an unusual cyclopalladation mechanism CHEMICAL COMMUNICATIONS Wang, M., Yang, Y., Fan, Z., Cheng, Z., Zhu, W., Zhang, A. 2015; 51 (15): 3219-3222


    We report the first example of Pd-catalyzed site-selective α-C(sp(3))-H oxidation/acetoxylation of amides through an unusual [4,6]-bicyclic metallacycle intermediate with 1-aminoanthraquinone as a new bidentate directing group. In addition to the distinct mechanism and high efficiency, the reaction is highly appealing due to the ample commercial source, low-cost, as well as easy removal and recycling of the auxiliary group.

    View details for DOI 10.1039/c4cc09576f

    View details for Web of Science ID 000349324200048

    View details for PubMedID 25603885

  • Cerenkov luminescence endoscopy: improved molecular sensitivity with ß--emitting radiotracers. Journal of nuclear medicine : official publication, Society of Nuclear Medicine Carpenter, C. M., Ma, X., Liu, H., Sun, C., Pratx, G., Wang, J., Gambhir, S. S., Xing, L., Cheng, Z. 2014; 55 (11): 1905-1909


    Cerenkov luminescence endoscopy (CLE) is an optical technique that captures the Cerenkov photons emitted from highly energetic moving charged particles (β(+) or β(-)) and can be used to monitor the distribution of many clinically available radioactive probes. A main limitation of CLE is its limited sensitivity to small concentrations of radiotracer, especially when used with a light guide. We investigated the improvement in the sensitivity of CLE brought about by using a β(-) radiotracer that improved Cerenkov signal due to both higher β-particle energy and lower γ noise in the imaging optics because of the lack of positron annihilation.The signal-to-noise ratio (SNR) of (90)Y was compared with that of (18)F in both phantoms and small-animal tumor models. Sensitivity and noise characteristics were demonstrated using vials of activity both at the surface and beneath 1 cm of tissue. Rodent U87MG glioma xenograft models were imaged with radiotracers bound to arginine-glycine-aspartate (RGD) peptides to determine the SNR.γ noise from (18)F was demonstrated by both an observed blurring across the field of view and a more pronounced fall-off with distance. A decreased γ background and increased energy of the β particles resulted in a 207-fold improvement in the sensitivity of (90)Y compared with (18)F in phantoms. (90)Y-bound RGD peptide produced a higher tumor-to-background SNR than (18)F in a mouse model.The use of (90)Y for Cerenkov endoscopic imaging enabled superior results compared with an (18)F radiotracer.

    View details for DOI 10.2967/jnumed.114.139105

    View details for PubMedID 25300598

  • Comparison of Two Site-Specifically F-18-Labeled Affibodies for PET Imaging of EGFR Positive Tumors MOLECULAR PHARMACEUTICS Su, X., Cheng, K., Jeon, J., Shen, B., Venturin, G. T., Hu, X., Rao, J., Chin, F. T., Wu, H., Cheng, Z. 2014; 11 (11): 3947-3956

    View details for DOI 10.1021/mp5003043

    View details for Web of Science ID 000344307700019

  • A Radiofluorinated Divalent Cystine Knot Peptide for Tumor PET Imaging MOLECULAR PHARMACEUTICS Jiang, L., Kimura, R. H., Ma, X., Tu, Y., Miao, Z., Shen, B., Chin, F. T., Shi, H., Gambhir, S. S., Cheng, Z. 2014; 11 (11): 3885-3892


    A divalent knottin containing two separate integrin binding epitopes (RGD) in the adjacent loops, 3-4A, was recently developed and reported in our previous publication. In the current study, 3-4A was radiofluorinated with a 4-nitrophenyl 2-(18)F-fluoropropinate ((18)F-NFP) group and the resulting divalent positron emission tomography (PET) probe, (18)F-FP-3-4A, was evaluated as a novel imaging probe to detect integrin αvβ3 positive tumors in living animals. Knottin 3-4A was synthesized by solid phase peptide synthesis, folded, and site-specifically conjugated with (18/19)F-NFP to produce the fluorinated peptide (18/19)F-fluoropropinate-3-4A ((18/19)F-FP-3-4A). The stability of (18)F-FP-3-4A was tested in both phosphate buffered saline (PBS) buffer and mouse serum. Cell uptake assays of the radiolabeled peptides were performed using U87MG cells. In addition, small animal PET imaging and biodistribution studies of (18)F-FP-3-4A were performed in U87MG tumor-bearing mice. The receptor targeting specificity of the radiolabeled peptide was also verified by coinjecting the probe with a blocking peptide cyclo(RGDyK). Our study showed that (18)F-FP-3-4A exhibited excellent stability in PBS buffer (pH 7.4) and mouse serum. Small animal PET imaging and biodistribution data revealed that (18)F-FP-3-4A exhibited rapid and good tumor uptake (3.76 ± 0.59% ID/g and 2.22 ± 0.62% ID/g at 0.5 and 1 h, respectively). (18)F-FP-3-4A was rapidly cleared from the normal tissues, resulting in excellent tumor-to-normal tissue contrasts. For example, liver uptake was only 0.39 ± 0.07% ID/g and the tumor to liver ratio was 5.69 at 1 h p.i. Furthermore, coinjection of cyclo(RGDyK) with (18)F-FP-3-4A significantly inhibited tumor uptake (0.41 ± 0.12 vs 1.02 ± 0.19% ID/g at 2.5 h) in U87MG xenograft models, demonstrating specific accumulation of the probe in the tumor. In summary, the divalent probe (18)F-FP-3-4A is characterized by rapid and high tumor uptake and excellent tumor-to-normal tissue ratios. (18)F-FP-3-4A is a highly promising knottin based PET probe for translating into clinical imaging of tumor angiogenesis.

    View details for DOI 10.1021/mp500018s

    View details for Web of Science ID 000344307700012

  • Design, synthesis and pharmacological evaluation of 2-(thiazol-2-amino)-4-arylaminopyrimidines as potent anaplastic lymphoma kinase (ALK) inhibitors EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY Liu, Z., Yue, X., Song, Z., Peng, X., Guo, J., Ji, Y., Cheng, Z., Ding, J., Ai, J., Geng, M., Zhang, A. 2014; 86: 438-448


    A series of new 2,4-diarylaminopyrimidine analogues (DAAPalogues) was developed by incorporation of a substituted 2-aminothiazole component as the C-2 substituent of the center pyrimidine core. Compound 5i showed highest potency of 12.4 nM against ALK and 24.1 nM against ALK gatekeeper mutation L1196M. Although only having moderate cellular potency in the SUP-M2 cells harboring NPM-ALK, compound 5i showed good kinase selectivity and dose-dependently inhibited phosphorylation of ALK and its down-stream signaling pathways.

    View details for DOI 10.1016/j.ejmech.2014.09.003

    View details for Web of Science ID 000343781800039

    View details for PubMedID 25200979

  • Transferring Biomarker into Molecular Probe: Melanin Nanoparticle as a Naturally Active Platform for Multimodality Imaging JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Fan, Q., Cheng, K., Hu, X., Ma, X., Zhang, R., Yang, M., Lu, X., Xing, L., Huang, W., Gambhir, S. S., Cheng, Z. 2014; 136 (43): 15185-15194


    Developing multifunctional and easily prepared nanoplatforms with integrated different modalities is highly challenging for molecular imaging. Here, we report the successful transferring an important molecular target, melanin, into a novel mul-timodality imaging nanoplatform. Melanin is abundantly expressed in melanotic melanomas and thus has been actively studied as a target for melanoma imaging. In our work, the multifunctional biopolymer nanoplatform based on ultrasmall (< 10 nm) water-soluble melanin nanoparticle (MNP) was developed and showed unique photoacoustic property and natural binding ability with metal ions (for example, 64Cu2+, Fe3+). Therefore MNP can serve not only as a photoacoustic contrast agent, but also as a nanoplatform for positron emission tomography (PET) and magnetic resonance imaging (MRI). Traditional passive nanoplatforms require complicated and time-consuming processes for pre-building reporting moieties or chemical modifications using active groups to integrate different contrast properties into one entity. In comparison, utilizing functional biomarker melanin can greatly simplify the building process. We further conjugated αvβ3 integrins targeting peptide, cyclic c(RGDfC) peptide, to MNPs and this allowed targeting of these nanoparticles to allow for greater U87MG tumor accumulation than that simply possible due to the enhanced permeability and retention (EPR) effect. The multimodal properties of MNPs demonstrate the high potential of endogenous materials with multifunctions as nanoplatforms for molecular theranostics and clinical translation.

    View details for DOI 10.1021/ja505412p

    View details for Web of Science ID 000344042900018

  • Optical image-guided cancer therapy. Current pharmaceutical biotechnology Bu, L., Ma, X., Tu, Y., Shen, B., Cheng, Z. 2014; 14 (8): 723-732


    Optical molecular imaging holds great promise for image guiding cancer therapy. The non-invasive guidance of therapeutic strategies would enable the removal of cancerous tissue while avoiding side effects and systemic toxicity, preventing damage of healthy tissues and decreasing the risk of postoperative problems. This review article highlights the advantages and disadvantages of the optical imaging techniques that are currently available, including their recent applications in image-guided cancer therapy. Three approaches for optical image-guided cancer therapy were discussed in this review, namely, bioluminescence imaging (BLI), fluorescence imaging (FI) and Cerenkov luminescence imaging (CLI). BLI is always used in small animal imaging for the in vivo tracking of therapeutic gene expression and cell-based therapy. To the contrary, FI display high promising for clinical translation. The applications of FI include image-guided surgery, radiotherapy, gene therapy, drug delivery and sentinel lymph node fluorescence mapping. CLI is a novel radioactive optical hybrid imaging strategy and its use for animal and clinical translation was also discussed. Perspectives on the translation of optical image-guided cancer therapy into clinical practice were provided.

    View details for PubMedID 24372233

  • Hybrid Nanotrimers for Dual T-1 and T-2-Weighted Magnetic Resonance Imaging ACS NANO Cheng, K., Yang, M., Zhang, R., Qin, C., Su, X., Cheng, Z. 2014; 8 (10): 9884-9896

    View details for DOI 10.1021/nn500188y

    View details for Web of Science ID 000343952600022

  • Imaging of hepatocellular carcinoma patient-derived xenografts using Zr-89-labeled anti-glypican-3 monoclonal antibody BIOMATERIALS Yang, X., Liu, H., Sun, C. K., Natarajan, A., Hu, X., Wang, X., Allegretta, M., Guttmann, R. D., Gambhir, S. S., Chua, M., Cheng, Z., So, S. K. 2014; 35 (25): 6964-6971


    Imaging probes for early detection of hepatocellular carcinoma (HCC) are highly desired to overcome current diagnostic limitations which lead to poor prognosis. The membrane protein glypican-3 (GPC3) is a potential molecular target for early HCC detection as it is over-expressed in >50% of HCCs, and is associated with early hepatocarcinogenesis. We synthesized the positron emission tomography (PET) probe (89)Zr-DFO-1G12 by bioconjugating and radiolabeling the anti-GPC3 monoclonal antibody (clone 1G12) with (89)Zr, and evaluated its tumor-targeting capacity. In vitro, (89)Zr-DFO-1G12 was specifically taken up into GPC3-positive HCC cells only, but not in the GPC3-negative prostate cancer cell line (PC3). In vivo, (89)Zr-DFO-1G12 specifically accumulated in subcutaneous GPC3-positive HCC xenografts only, but not in PC3 xenografts. Importantly, (89)Zr-DFO-1G12 delineated orthotopic HCC xenografts from surrounding normal liver, with tumor/liver (T/L) ratios of 6.65 ± 1.33 for HepG2, and 4.29 ± 0.52 for Hep3B xenografts. It also delineated orthotopic xenografts derived from three GPC3-positive HCC patient specimens, with T/L ratios of 4.21 ± 0.64, 2.78 ± 0.26, and 2.31 ± 0.38 at 168 h p.i. Thus, (89)Zr-DFO-1G12 is a highly translatable probe for the specific and high contrast imaging of GPC3-positive HCCs, which may aid early detection of HCC to allow timely intervention.

    View details for DOI 10.1016/j.biomaterials.2014.04.089

    View details for Web of Science ID 000338386800028

  • Optical imaging of articular cartilage degeneration using near-infrared dipicolylamine probes. Biomaterials Hu, X., Wang, Q., Liu, Y., Liu, H., Qin, C., Cheng, K., Robinson, W., Gray, B. D., Pak, K. Y., Yu, A., Cheng, Z. 2014; 35 (26): 7511-7521


    Articular cartilage is the hydrated tissue that lines the ends of long bones in load bearing joints and provides joints with a smooth, nearly frictionless gliding surface. However, the deterioration of articular cartilage occurs in the early stages of osteoarthritis (OA) and is clinically and radiographically silent. Here two cationic near infrared fluorescent (NIRF) dipicolylamine (DPA) probes, Cy5-DPA-Zn and Cy7-DPA-Zn, were prepared for cartilage degeneration imaging and OA early detection through binding to the anionic glycosaminoglycans (GAGs). The feasibility of NIRF dye labeled DPA-Zn probes for cartilage degeneration imaging was examined ex vivo and in vivo. The ex vivo studies showed that Cy5-DPA-Zn and Cy7-DPA-Zn not only showed the high uptake and electrostatic attractive binding to cartilage, but also sensitively reflected the change of GAGs contents. In vivo imaging study further indicated that Cy5-DPA-Zn demonstrated higher uptake and retention in young mice (high GAGs) than old mice (low GAGs) when administrated via local injection in mouse knee joints. More importantly, Cy5-DPA-Zn showed dramatic higher signals in sham joint (high GAGs) than OA side (low GAGs), through sensitive reflecting the change of GAGs in the surgical induced OA models. In summary, Cy5-DPA-Zn provides promising visual detection for early cartilage pathological degeneration in living subjects.

    View details for DOI 10.1016/j.biomaterials.2014.05.042

    View details for PubMedID 24912814

  • Design, synthesis and biological evaluation of mitochondria targeting theranostic agents. Chemical communications Wu, S., Cao, Q., Wang, X., Cheng, K., Cheng, Z. 2014; 50 (64): 8919-8922


    Dual mitochondria targeting fluorescent F16-TPP analogues were designed and synthesized. Uptake and cytotoxicity studies indicate that FF16 and FF16-TPP, two compounds discovered in this study, are promising mitochondria targeting theranostic agents.

    View details for DOI 10.1039/c4cc03296a

    View details for PubMedID 24976119

  • Intrastriatal Transplantation of Retinal Pigment Epithelial Cells for the Treatment of Parkinson Disease: In Vivo Longitudinal Molecular Imaging with (18)F-P3BZA PET/CT. Radiology Bu, L., Li, R., Liu, H., Feng, W., Xiong, X., Zhao, H., Vollrath, D., Shen, B., Cheng, Z. 2014; 272 (1): 174-183


    Purpose To evaluate the performance of N-[2-(diethylamino)ethyl]-(18)F-5-fluoropicolinamide ((18)F-P3BZA) for visualizing porcine retinal pigment epithelium (pRPE) cells transplanted in the striatum for the treatment of Parkinson disease and to monitor the long-term activity of implanted pRPE cells by means of (18)F-P3BZA positron emission tomography (PET)/computed tomography (CT) in vivo. Materials and Methods Animal work was conducted in accordance with the administrative panel on laboratory animal care. In vitro cell uptake of (18)F-P3BZA was determined with incubation of melanotic pRPE or amelanotic ARPE-19 cells with (18)F-P3BZA. To visualize the implanted pRPE cells in vivo, normal rats (four per group) were injected with pRPE or ARPE-19 cells attached to gelatin microcarriers in the left striatum and with control gelatin microcarriers in the right striatum and followed up with small animal PET/CT. Longitudinal PET/CT scans were acquired in 12 rats up to 16 days after surgery. Postmortem analysis, which included autoradiography and hematoxylin-eosin, Fontana-Masson, and immunofluorescence staining, was performed. Data were compared with the Student t test, analysis of variance, and regression analysis. Results (18)F-P3BZA accumulated in pRPE cells effectively (3.48% of the injected dose [ID] per gram of brain tissue ± 0.58 at 1 hour after injection of the probe at 2 days after surgery in vivo) but not in control ARPE-19 cells (P < .05). Longitudinal PET/CT scans revealed that the activity of implanted pRPE cells decreased over time, as evidenced by a reduction in (18)F-P3BZA uptake (3.39% ID/g ± 0.18, 2.49% ID/g ± 0.41, and 1.20% ID/g ± 0.13 at days 2, 9, and 16, respectively; P < .05). Postmortem analysis helped confirm the results of in vivo imaging. Conclusion (18)F-P3BZA PET/CT is a feasible technique for visualizing and detecting the activity of implanted RPE cells in vivo. © RSNA, 2014 Online supplemental material is available for this article.

    View details for DOI 10.1148/radiol.14132042

    View details for PubMedID 24758555

  • Molecular imaging for assessment of mesenchymal stem cells mediated breast cancer therapy BIOMATERIALS Leng, L., Wang, Y., He, N., Wang, D., Zhao, Q., Feng, G., Su, W., Xu, Y., Han, Z., Kong, D., Cheng, Z., Xiang, R., Li, Z. 2014; 35 (19): 5162-5170


    The tumor tropism of mesenchymal stem cells (MSCs) makes them an excellent delivery vehicle used in anticancer therapy. However, the exact mechanisms of MSCs involved in tumor microenvironment are still not well defined. Molecular imaging technologies with the versatility in monitoring the therapeutic effects, as well as basic molecular and cellular processes in real time, offer tangible options to better guide MSCs mediated cancer therapy. In this study, an in situ breast cancer model was developed with MDA-MB-231 cells carrying a reporter system encoding a double fusion (DF) reporter gene consisting of firefly luciferase (Fluc) and enhanced green fluorescent protein (eGFP). In mice breast cancer model, we injected human umbilical cord-derived MSCs (hUC-MSCs) armed with a triple fusion (TF) gene containing the herpes simplex virus truncated thymidine kinase (HSV-ttk), renilla luciferase (Rluc) and red fluorescent protein (RFP) into tumor on day 13, 18, 23 after MDA-MB-231 cells injection. Bioluminescence imaging of Fluc and Rluc provided the real time monitor of tumor cells and hUC-MSCs simultaneously. We found that tumors were significantly inhibited by hUC-MSCs administration, and this effect was enhanced by ganciclovir (GCV) application. To further demonstrate the effect of hUC-MSCs on tumor cells in vivo, we employed the near infrared (NIR) imaging and the results showed that hUC-MSCs could inhibit tumor angiogenesis and increased apoptosis to a certain degree. In conclusion, hUC-MSCs can inhibit breast cancer progression by inducing tumor cell death and suppressing angiogenesis. Moreover, molecular imaging is an invaluable tool in tracking cell delivery and tumor response to hUC-MSCs therapies as well as cellular and molecular processes in tumor.

    View details for DOI 10.1016/j.biomaterials.2014.03.014

    View details for Web of Science ID 000335705600013

    View details for PubMedID 24685267

  • In vitro and in vivo direct monitoring of miRNA-22 expression in isoproterenol-induced cardiac hypertrophy by bioluminescence imaging EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING Tu, Y., Wan, L., Zhao, D., Bu, L., Dong, D., Yin, Z., Cheng, Z., Shen, B. 2014; 41 (5): 972-984


    Growing evidence suggests that microRNAs (miRNAs) play key roles in cardiac hypertrophy. To measure the expression of endogenous miRNAs is very conducive to understanding the importance of miRNAs in cardiac hypertrophy. However, current methods to monitor endogenous miRNA levels, such as Northern blotting, quantitative real-time polymerase chain reaction (qRT-PCR), and microarrays cannot provide real-time information on miRNA biogenesis in vivo.We constructed a miRNA reporter imaging system to monitor miR-22 expression in isoproterenol-induced cardiac hypertrophy repetitively and noninvasively. There were three copies of the antisense of miR-22 (3×PT_miR-22) cloned into the 3' untranslated region (UTR) of the Gaussia luciferase (Gluc) reporter genes under the control of the cytomegalovirus (CMV) promoter in this miRNA reporter system (CMV/Gluc/3×PT_miR-22). CMV/firefly luciferase (Fluc) was used as a positive control for imaging of miR-22 expression. Meanwhile, quantifications of miR-22 in cardiomyocyte hypertrophy and in mouse cardiac hypertrophy induced by isoproterenol stimulation were measured by qRT-PCR. Furthermore, we used this miRNA reporter imaging system to appraise the antihypertrophic effect of antagomir-22 in vitro and in vivo.The bioluminescence signals of the CMV/Gluc/3×PT_miR-22 were gradually decreased with prolongation of isoproterenol intervention in vitro and in vivo. Overexpression of miR-22 was observed in cardiac hypertrophy, and markedly administration of antagomir-22 could reverse the upregulation of miR-22 and its prohypertrophic effects. Furthermore, knockdown of miR-22 by antagomir-22 could markedly reverse the repressed Gluc activities in vitro and in vivo. However, the Fluc activity of CMV/Fluc was not affected with isoproterenol treatment.This study elucidates the feasibility of using our constructed miRNA reporter imaging system to monitor the location and magnitude of expression levels of miR-22 in cardiac hypertrophy in vitro and in vivo.

    View details for DOI 10.1007/s00259-013-2596-3

    View details for Web of Science ID 000334417900020

    View details for PubMedID 24504502

  • Theranostics of Malignant Melanoma with 64CuCl2. Journal of nuclear medicine Qin, C., Liu, H., Chen, K., Hu, X., Ma, X., Lan, X., Zhang, Y., Cheng, Z. 2014; 55 (5): 812-817


    Human copper transporter 1 (CTR1) is overexpressed in a variety of cancers. This study aimed to evaluate the use of (64)CuCl2 as a theranostic agent for PET and radionuclide therapy of malignant melanoma.CTR1 expression levels were detected by Western blot analysis of a group of tumor cell lines. Two melanoma cell lines (B16F10 and A375M) that highly expressed CTR1 were then selected to study the uptake and efflux of (64)CuCl2. Mice bearing B16F10 or A375M tumors (n = 4 for each group) were subjected to 5 min of static whole-body PET scans at different time points after intravenous injection of (64)CuCl2. Dynamic scans were also obtained for B16F10 tumor-bearing mice. All mice were sacrificed at 72 h after injection of (64)CuCl2, and biodistribution studies were performed. Mice bearing B16F10 or A375M tumors were further subjected to (64)CuCl2 radionuclide therapy. Specifically, when the tumor size reached 0.5-0.8 cm in diameter, tumor-bearing mice were systemically administered (64)CuCl2 (74 MBq) or phosphate-buffered saline, and tumor sizes were monitored over the treatment period.CTR1 was found to be overexpressed in the cancer cell lines tested at different levels, and high expression levels in melanoma cells and tissues were observed (melanotic B16F10 and amelanotic A375M). (64)CuCl2 displayed high and specific uptake in B16F10 and A375M cells. In vivo (64)CuCl2 PET imaging demonstrated that both B16F10 and A375M tumors were clearly visualized. Radionuclide treatment studies showed that the tumor growth in both the B16F10 and the A375M models under (64)CuCl2 treatment were much slower than that of the control group.Both melanotic and amelanotic melanomas (B16F10 and A375M) tested were found to overexpress CTR1. The tumors can be successfully visualized by (64)CuCl2 PET and further treated by (64)CuCl2, highlighting the high potential of using (64)CuCl2 as a theranostic agent for the management of melanoma.

    View details for DOI 10.2967/jnumed.113.133850

    View details for PubMedID 24627435

  • Up-regulated isocitrate dehydrogenase 1 suppresses proliferation, migration and invasion in osteosarcoma: In vitro and in vivo. Cancer letters Hu, X., Liu, Y., Qin, C., Pan, Z., Luo, J., Yu, A., Cheng, Z. 2014; 346 (1): 114-121


    Very few studies have been reported the function of wild type IDH1 in tumor progress. Previously, we reported that IDH1 correlated with pathological grade and metastatic potential inversely in human osteosarcoma. Here, IDH1 was found lower expressed in osteosarcoma tissues than that of adjacent normal bone tissues. In addition, we observed in vitro anti-proliferation and pro-apoptosis effects of up-regulated IDH1 on osteosarcoma cell lines. The migration and invasion activity was also markedly reduced by IDH1 up-regulation. Unexpectedly, IDH1 up-regulation also suppressed tumor growth and metastasis in vivo. Therefore, IDH1 may represent a potential novel treatment and preventive strategy for osteosarcoma.

    View details for DOI 10.1016/j.canlet.2013.12.020

    View details for PubMedID 24368190

  • Tc-99m-Labeled Cystine Knot Peptide Targeting Integrin alpha(v)beta(6) for Tumor SPECT Imaging MOLECULAR PHARMACEUTICS Zhu, X., Li, J., Hong, Y., Kimura, R. H., Ma, X., Liu, H., Qin, C., Hu, X., Hayes, T. R., Benny, P., Gambhir, S. S., Cheng, Z. 2014; 11 (4): 1208-1217


    Integrin αvβ6 is overexpressed in a variety of cancers, and its expression is often associated with poor prognosis. Therefore, there is a need to develop affinity reagents for noninvasive imaging of integrin αvβ6 expression since it may provide early cancer diagnosis, more accurate prognosis, and better treatment planning. We recently engineered and validated highly stable cystine knot peptides that selectively bind integrin αvβ6 with no cross-reactivity to integrins αvβ5, α5β1, or αvβ3, also known to be overexpressed in many cancers. Here, we developed a single photon emission computed tomography (SPECT) probe for imaging integrin αvβ6 positive tumors. Cystine knot peptide, S02, was first conjugated with a single amino acid chelate (SAAC) and labeled with [(99m)Tc(H2O)3(CO)3](+). The resulting probe, (99m)Tc-SAAC-S02, was then evaluated by in vitro cell uptake studies using two αvβ6 positive cell lines (human lung adenocarcinoma cell line HCC4006 and pancreatic cancer cell line BxPC-3) and two αvβ6 negative cell lines (human lung adenocarcinoma cell line H838 and human embryonic kidney cell line 293T). Next, SPECT/CT and biodistribution studies were performed in nude mice bearing HCC4006 and H838 tumor xenografts to evaluate the in vivo performance of (99m)Tc-SAAC-S02. Significant differences in the uptake of (99m)Tc-SAAC-S02 were observed in αvβ6 positive vs negative cells (P < 0.05). Biodistribution and small animal SPECT/CT studies revealed that (99m)Tc-SAAC-S02 accumulated to moderate levels in antigen positive tumors (∼2% ID/g at 1 and 6 h postinjection, n = 3 or 4/group). Moreover, the probe demonstrated tumor-to-background tissue ratios of 6.81 ± 2.32 (tumor-to-muscle) and 1.63 ± 0.18 (tumor-to-blood) at 6 h postinjection in αvβ6 positive tumor xenografts. Co-incubation of the probe with excess amount of unlabeled S02 as a blocking agent demonstrated significantly reduced tumor uptake, which is consistent with specific binding to the target. Renal filtration was the main route of clearance. In conclusion, knottin peptides are excellent scaffolds for which to develop highly stable imaging probes for a variety of oncological targets. (99m)Tc-SAAC-S02 demonstrates promise for use as a SPECT agent to image integrin αvβ6 expression in living systems.

    View details for DOI 10.1021/mp400683q

    View details for Web of Science ID 000334092700013

    View details for PubMedCentralID PMC3993876

  • Multimodality Molecular Imaging to Monitor Transplanted Stem Cells for the Treatment of Ischemic Heart Disease PLOS ONE Pei, Z., Lan, X., Cheng, Z., Qin, C., Xia, X., Yuan, H., Ding, Z., Zhang, Y. 2014; 9 (3)


    Non-invasive techniques to monitor the survival and migration of transplanted stem cells in real-time is crucial for the success of stem cell therapy. The aim of this study was to explore multimodality molecular imaging to monitor transplanted stem cells with a triple-fused reporter gene [TGF; herpes simplex virus type 1 thymidine kinase (HSV1-tk), enhanced green fluorescence protein (eGFP), and firefly luciferase (FLuc)] in acute myocardial infarction rat models.Rat myocardial infarction was established by ligating the left anterior descending coronary artery. A recombinant adenovirus carrying TGF (Ad5-TGF) was constructed. After transfection with Ad5-TGF, 5 × 10(6) bone marrow mesenchymal stem cells (BMSCs) were transplanted into the anterior wall of the left ventricle (n = 14). Untransfected BMSCs were as controls (n = 8). MicroPET/CT, fluorescence and bioluminescence imaging were performed. Continuous images were obtained at day 2, 3 and 7 after transplantation with all three imaging modalities and additional images were performed with bioluminescence imaging until day 15 after transplantation.High signals in the heart area were observed using microPET/CT, fluorescence and bioluminescence imaging of infarcted rats injected with Ad5-TGF-transfected BMSCs, whereas no signals were observed in controls. Semi-quantitative analysis showed the gradual decrease of signals in all three imaging modalities with time. Immunohistochemistry assays confirmed the location of the TGF protein expression was the same as the site of stem cell-specific marker expression, suggesting that TGF tracked the stem cells in situ.We demonstrated that TGF could be used as a reporter gene to monitor stem cells in a myocardial infarction model by multimodality molecular imaging.

    View details for DOI 10.1371/journal.pone.0090543

    View details for Web of Science ID 000332485800031

    View details for PubMedID 24608323

    View details for PubMedCentralID PMC3946457

  • Construction and validation of nano gold tripods for molecular imaging of living subjects. Journal of the American Chemical Society Cheng, K., Kothapalli, S., Liu, H., Koh, A. L., Jokerst, J. V., Jiang, H., Yang, M., Li, J., Levi, J., Wu, J. C., Gambhir, S. S., Cheng, Z. 2014; 136 (9): 3560-3571


    Anisotropic colloidal hybrid nanoparticles exhibit superior optical and physical properties compared to their counterparts with regular architectures. We herein developed a controlled, stepwise strategy to build novel, anisotropic, branched, gold nanoarchitectures (Au-tripods) with predetermined composition and morphology for bioimaging. The resultant Au-tripods with size less than 20 nm showed great promise as contrast agents for in vivo photoacoustic imaging (PAI). We further identified Au-tripods with two possible configurations as high-absorbance nanomaterials from various gold multipods using a numerical simulation analysis. The PAI signals were linearly correlated with their concentrations after subcutaneous injection. The in vivo biodistribution of Au-tripods favorable for molecular imaging was confirmed using small animal positron emission tomography (PET). Intravenous administration of cyclic Arg-Gly-Asp-d-Phe-Cys (RGDfC) peptide conjugated Au-tripods (RGD-Au-tripods) to U87MG tumor-bearing mice showed PAI contrasts in tumors almost 3-fold higher than for the blocking group. PAI results correlated well with the corresponding PET images. Quantitative biodistribution data revealed that 7.9% ID/g of RGD-Au-tripods had accumulated in the U87MG tumor after 24 h post-injection. A pilot mouse toxicology study confirmed that no evidence of significant acute or systemic toxicity was observed in histopathological examination. Our study suggests that Au-tripods can be reliably synthesized through stringently controlled chemical synthesis and could serve as a new generation of platform with high selectivity and sensitivity for multimodality molecular imaging.

    View details for DOI 10.1021/ja412001e

    View details for PubMedID 24495038

  • NIR-light-induced surface-enhanced Raman scattering for detection and photothermal/photodynamic therapy of cancer cells using methylene blue-embedded gold nanorod@SiO2 nanocomposites BIOMATERIALS Seo, S., Kim, B., Joe, A., Han, H., Chen, X., Cheng, Z., Jang, E. 2014; 35 (10): 3309-3318


    Methylene blue-loaded gold nanorod@SiO2 (MB-GNR@SiO2) core@shell nanoparticles are synthesized for use in cancer imaging and photothermal/photodynamic dual therapy. For the preparation of GNR@SiO2 nanoparticles, we found that the silica coating rate of hexadecylcetyltrimethylammonium bromide (CTAB)-capped GNRs is much slower than that of PEGylated GNRs due to the densely coated CTAB bilayer. Encapsulated MB molecules have both monomer and dimer forms that result in an increase in the photosensitizing effect through different photochemical pathways. As a consequence of the excellent plasmonic properties of GNRs at near-infrared (NIR) light, the embedded MB molecules showed NIR light-induced SERS performance with a Raman enhancement factor of 3.0 × 10(10), which is enough for the detection of a single cancer cell. Moreover, the MB-GNR@SiO2 nanoparticles exhibit a synergistic effect of photodynamic and photothermal therapies of cancer under single-wavelength NIR laser irradiation.

    View details for DOI 10.1016/j.biomaterials.2013.12.066

    View details for PubMedID 24424205

  • SM5-1-Conjugated PLA nanoparticles loaded with 5-fluorouracil for targeted hepatocellular carcinoma imaging and therapy BIOMATERIALS Ma, X., Cheng, Z., Jin, Y., Liang, X., Yang, X., Dai, Z., Tian, J. 2014; 35 (9): 2878-2889


    SM5-1 is a humanized mouse antibody which has a high binding specificity for a membrane protein of about 230 kDa overexpressed in hepatocellular carcinoma (HCC), melanoma and breast cancer. In this study, SM5-1-conjugated poly D, L (lactide-coglycolide) (PLA) PLA containing Cy7 (PLA-Cy7-SM5-1) was prepared to study the targeting specificity of the bioconjugate to HCC-LM3-fLuc cell. Then, SM5-1-conjugated PLA containing 5-fluorouracil (5-FU) (PLA-5FU-SM5-1) and PLA containing 5-FU (PLA-5FU) were prepared for treatment of subcutaneous HCC-LM3-fLuc tumor mice. The results showed that PLA-5FU-SM5-1, PLA-5FU and 5-FU induced a 45.07%, 23.56% and 19.05% tumor growth inhibition rate, respectively, on day 31 post-treatment as determined by bioluminescent intensity. In addition, in order to evaluate the antitumor efficacy of PLA-5FU-SM5-1, HCC-LM3-fLuc cells were injected into the liver to establish the experimental orthotopic liver tumor models. The experiments showed that PLA-5FU-SM5-1, PLA-5FU and 5-FU induced a 53.24%, 31.00%, and 18.11% tumor growth inhibition rate, respectively, on day 31 post-treatment determined by the bioluminescent intensity of the abdomen in tumor-bearing mice. Furthermore, we have calculated the three-dimensional location of the liver cancer in mice using a multilevel adaptive finite element algorithm based on bioluminescent intensity decay calibration. The reconstruction results demonstrated that PLA-5FU-SM5-1 inhibited the tumor rapid progression, which were consistent with the results of subcutaneous tumor mice experiments and in vitro cell experiment results.

    View details for DOI 10.1016/j.biomaterials.2013.12.045

    View details for Web of Science ID 000332188900031

    View details for PubMedID 24411331

  • Clickable, Hydrophilic Ligand for fac-[M-I(CO)(3)](+) (M = Re/Tc-99m) Applied in an S-Functionalized alpha-MSH Peptide BIOCONJUGATE CHEMISTRY Kasten, B. B., Ma, X., Liu, H., Hayes, T. R., Barnes, C. L., Qi, S., Cheng, K., Bottorff, S. C., Slocumb, W. S., Wang, J., Cheng, Z., Benny, P. D. 2014; 25 (3): 579-592


    The copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction was used to incorporate alkyne-functionalized dipicolylamine (DPA) ligands (1 and 3) for fac-[M(I)(CO)3](+) (M = Re/(99m)Tc) complexation into an α-melanocyte stimulating hormone (α-MSH) peptide analogue. A novel DPA ligand with carboxylate substitutions on the pyridyl rings (3) was designed to increase the hydrophilicity and to decrease in vivo hepatobiliary retention of fac-[(99m)Tc(I)(CO)3](+) complexes used in single photon emission computed tomography (SPECT) imaging studies with targeting biomolecules. The fac-[Re(I)(CO)3(3)] complex (4) was used for chemical characterization and X-ray crystal analysis prior to radiolabeling studies between 3 and fac-[(99m)Tc(I)(OH2)3(CO)3](+). The corresponding (99m)Tc complex (4a) was obtained in high radiochemical yields, was stable in vitro for 24 h during amino acid challenge and serum stability assays, and showed increased hydrophilicity by log P analysis compared to an analogous complex with nonfunctionalized pyridine rings (2a). An α-MSH peptide functionalized with an azide was labeled with fac-[M(I)(CO)3](+) using both click, then chelate (CuAAC reaction with 1 or 3 followed by metal complexation) and chelate, then click (metal complexation of 1 and 3 followed by CuAAC with the peptide) strategies to assess the effects of CuAAC conditions on fac-[M(I)(CO)3](+) complexation within a peptide framework. The peptides from the click, then chelate strategy had different HPLC tR's and in vitro stabilities compared to those from the chelate, then click strategy, suggesting nonspecific coordination of fac-[M(I)(CO)3](+) using this synthetic route. The fac-[M(I)(CO)3](+)-complexed peptides from the chelate, then click strategy showed >90% stability during in vitro challenge conditions for 6 h, demonstrated high affinity and specificity for the melanocortin 1 receptor (MC1R) in IC50 analyses, and led to moderately high uptake in B16F10 melanoma cells. Log P analysis of the (99m)Tc-labeled peptides confirmed the enhanced hydrophilicity of the peptide bearing the novel, carboxylate-functionalized DPA chelate (10a') compared to the peptide with the unmodified DPA chelate (9a'). In vivo biodistribution analysis of 9a' and 10a' showed moderate tumor uptake in a B16F10 melanoma xenograft mouse model with enhanced renal uptake and surprising intestinal uptake for 10a' compared to predominantly hepatic accumulation for 9a'. These results, coupled with the versatility of CuAAC, suggests this novel, hydrophilic chelate can be incorporated into numerous biomolecules containing azides for generating targeted fac-[M(I)(CO)3](+) complexes in future studies.

    View details for DOI 10.1021/bc5000115

    View details for Web of Science ID 000333435900014

    View details for PubMedID 24568284

    View details for PubMedCentralID PMC3983144

  • A Radiofluorinated Divalent Cystine Knot Peptide for Tumor PET Imaging. Molecular pharmaceutics Jiang, L. n., Kimura, R. H., Ma, X. n., Tu, Y. n., Miao, Z. n., Shen, B. n., Chin, F. T., Shi, H. n., Gambhir, S. S., Cheng, Z. n. 2014


    A divalent knottin containing two separate integrin binding epitopes (RGD) in the adjacent loops, 3-4A, was recently developed and reported in our previous publication. In the current study, 3-4A was radiofluorinated with a 4-nitrophenyl 2-(18)F-fluoropropinate ((18)F-NFP) group and the resulting divalent positron emission tomography (PET) probe, (18)F-FP-3-4A, was evaluated as a novel imaging probe to detect integrin αvβ3 positive tumors in living animals. Knottin 3-4A was synthesized by solid phase peptide synthesis, folded, and site-specifically conjugated with (18/19)F-NFP to produce the fluorinated peptide (18/19)F-fluoropropinate-3-4A ((18/19)F-FP-3-4A). The stability of (18)F-FP-3-4A was tested in both phosphate buffered saline (PBS) buffer and mouse serum. Cell uptake assays of the radiolabeled peptides were performed using U87MG cells. In addition, small animal PET imaging and biodistribution studies of (18)F-FP-3-4A were performed in U87MG tumor-bearing mice. The receptor targeting specificity of the radiolabeled peptide was also verified by coinjecting the probe with a blocking peptide cyclo(RGDyK). Our study showed that (18)F-FP-3-4A exhibited excellent stability in PBS buffer (pH 7.4) and mouse serum. Small animal PET imaging and biodistribution data revealed that (18)F-FP-3-4A exhibited rapid and good tumor uptake (3.76 ± 0.59% ID/g and 2.22 ± 0.62% ID/g at 0.5 and 1 h, respectively). (18)F-FP-3-4A was rapidly cleared from the normal tissues, resulting in excellent tumor-to-normal tissue contrasts. For example, liver uptake was only 0.39 ± 0.07% ID/g and the tumor to liver ratio was 5.69 at 1 h p.i. Furthermore, coinjection of cyclo(RGDyK) with (18)F-FP-3-4A significantly inhibited tumor uptake (0.41 ± 0.12 vs 1.02 ± 0.19% ID/g at 2.5 h) in U87MG xenograft models, demonstrating specific accumulation of the probe in the tumor. In summary, the divalent probe (18)F-FP-3-4A is characterized by rapid and high tumor uptake and excellent tumor-to-normal tissue ratios. (18)F-FP-3-4A is a highly promising knottin based PET probe for translating into clinical imaging of tumor angiogenesis.

    View details for DOI 10.1021/mp500018s

    View details for PubMedID 24717098

  • Imaging of hepatocellular carcinoma patient-derived xenografts using (89)Zr-labeled anti-glypican-3 monoclonal antibody. Biomaterials Yang, X. n., Liu, H. n., Sun, C. K., Natarajan, A. n., Hu, X. n., Wang, X. n., Allegretta, M. n., Guttmann, R. D., Gambhir, S. S., Chua, M. S., Cheng, Z. n., So, S. K. 2014; 35 (25): 6964–71


    Imaging probes for early detection of hepatocellular carcinoma (HCC) are highly desired to overcome current diagnostic limitations which lead to poor prognosis. The membrane protein glypican-3 (GPC3) is a potential molecular target for early HCC detection as it is over-expressed in >50% of HCCs, and is associated with early hepatocarcinogenesis. We synthesized the positron emission tomography (PET) probe (89)Zr-DFO-1G12 by bioconjugating and radiolabeling the anti-GPC3 monoclonal antibody (clone 1G12) with (89)Zr, and evaluated its tumor-targeting capacity. In vitro, (89)Zr-DFO-1G12 was specifically taken up into GPC3-positive HCC cells only, but not in the GPC3-negative prostate cancer cell line (PC3). In vivo, (89)Zr-DFO-1G12 specifically accumulated in subcutaneous GPC3-positive HCC xenografts only, but not in PC3 xenografts. Importantly, (89)Zr-DFO-1G12 delineated orthotopic HCC xenografts from surrounding normal liver, with tumor/liver (T/L) ratios of 6.65 ± 1.33 for HepG2, and 4.29 ± 0.52 for Hep3B xenografts. It also delineated orthotopic xenografts derived from three GPC3-positive HCC patient specimens, with T/L ratios of 4.21 ± 0.64, 2.78 ± 0.26, and 2.31 ± 0.38 at 168 h p.i. Thus, (89)Zr-DFO-1G12 is a highly translatable probe for the specific and high contrast imaging of GPC3-positive HCCs, which may aid early detection of HCC to allow timely intervention.

    View details for PubMedID 24836949

  • PET probes beyond (18)F-FDG. Journal of biomedical research Jiang, L. n., Tu, Y. n., Shi, H. n., Cheng, Z. n. 2014; 28 (6): 435–46


    During the past several decades, positron emission tomography (PET) has been one of the rapidly growing areas of medical imaging; particularly, its applications in routine oncological practice have been widely recognized. At present, (18)F-fluorodeoxyglucose ((18)F-FDG) is the most broadly used PET probe. However, (18)F-FDG also suffers many limitations. Thus, scientists and clinicians are greatly interested in exploring and developing new PET imaging probes with high affinity and specificity. In this review, we briefly summarize the representative PET probes beyond (18)F-FDG that are available for patients imaging in three major clinical areas (oncology, neurology and cardiology), and we also discuss the feasibility and trends in developing new PET probes for personalized medicine.

    View details for PubMedID 25469112

    View details for PubMedCentralID PMC4250522

  • A novel Affibody bioconjugate for dual-modality imaging of ovarian cancer CHEMICAL COMMUNICATIONS Wang, Y., Miao, Z., Ren, G., Xu, Y., Cheng, Z. 2014; 50 (85): 12832-12835

    View details for DOI 10.1039/c4cc03454f

    View details for Web of Science ID 000342756100005

  • Fluorescent imaging of cancerous tissues for targeted surgery. Advanced drug delivery reviews Bu, L. n., Shen, B. n., Cheng, Z. n. 2014; 76C: 21–38


    To maximize tumor excision and minimize collateral damage are the primary goals of cancer surgery. Emerging molecular imaging techniques have made "image-guided surgery" developed into "molecular imaging-guided surgery", which is termed as "targeted surgery" in this review. Consequently, the precision of surgery can be advanced from tissue-scale to molecule-scale, enabling "targeted surgery" to be a component of "targeted therapy". Evidence from numerous experimental and clinical studies has demonstrated significant benefits of fluorescent imaging in targeted surgery with preoperative molecular diagnostic screening. Fluorescent imaging can help to improve intraoperative staging and enable more radical cytoreduction, detect obscure tumor lesions in special organs, highlight tumor margins, better map lymph node metastases, and identify important normal structures intraoperatively. Though limited tissue penetration of fluorescent imaging and tumor heterogeneity are two major hurdles for current targeted surgery, multimodality imaging and multiplex imaging may provide potential solutions to overcome these issues, respectively. Moreover, though many fluorescent imaging techniques and probes have been investigated, targeted surgery remains at a proof-of-principle stage. The impact of fluorescent imaging on cancer surgery will likely be realized through persistent interdisciplinary amalgamation of research in diverse fields.

    View details for PubMedID 25064553

    View details for PubMedCentralID PMC4169718

  • Assessing the barriers to image-guided drug delivery WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY Lanza, G. M., Moonen, C., Baker, J. R., Chang, E., Cheng, Z., Grodzinski, P., Ferrara, K., Hynynen, K., Kelloff, G., Lee, Y. K., Patri, A. K., Sept, D., Schnitzer, J. E., Wood, B. J., Zhang, M., Zheng, G., Farahani, K. 2014; 6 (1): 1-14


    Imaging has become a cornerstone for medical diagnosis and the guidance of patient management. A new field called image-guided drug delivery (IGDD) now combines the vast potential of the radiological sciences with the delivery of treatment and promises to fulfill the vision of personalized medicine. Whether imaging is used to deliver focused energy to drug-laden particles for enhanced, local drug release around tumors, or it is invoked in the context of nanoparticle-based agents to quantify distinctive biomarkers that could risk stratify patients for improved targeted drug delivery efficiency, the overarching goal of IGDD is to use imaging to maximize effective therapy in diseased tissues and to minimize systemic drug exposure in order to reduce toxicities. Over the last several years, innumerable reports and reviews covering the gamut of IGDD technologies have been published, but inadequate attention has been directed toward identifying and addressing the barriers limiting clinical translation. In this consensus opinion, the opportunities and challenges impacting the clinical realization of IGDD-based personalized medicine were discussed as a panel and recommendations were proffered to accelerate the field forward.

    View details for DOI 10.1002/wnan.1247

    View details for Web of Science ID 000328354300001

    View details for PubMedID 24339356

    View details for PubMedCentralID PMC3967549

  • A Comparative Study of Radio labeled Bombesin Analogs for the PET Imaging of Prostate Cancer JOURNAL OF NUCLEAR MEDICINE Liu, Y., Hu, X., Liu, H., Bu, L., Ma, X., Cheng, K., Li, J., Tian, M., Zhang, H., Cheng, Z. 2013; 54 (12): 2132-2138


    Radiolabeled bombesin (BBN) analogs that bind to the gastrin-releasing peptide receptor (GRPR) represent a topic of active investigation for the development of molecular probes for PET or SPECT of prostate cancer (PCa). RM1 and AMBA have been identified as the 2 most promising BBN peptides for GRPR-targeted cancer imaging and therapy. In this study, to develop a clinically translatable BBN-based PET probe, we synthesized and evaluated (18)F-AlF- (aluminum-fluoride) and (64)Cu-radiolabeled RM1 and AMBA analogs for their potential application in PET imaging of PCa.1,4,7-triazacyclononane, 1-glutaric acid-4,7 acetic acid (NODAGA)-conjugated RM1 and AMBA were synthesized and tested for their GRPR-binding affinities. The NODAGA-RM1 and NODAGA-AMBA probes were further radiolabeled with (64)Cu or (18)F-AlF and then evaluated in a subcutaneous PCa xenograft model (PC3) by small-animal PET imaging and biodistribution studies.NODAGA-RM1 and NODAGA-AMBA can be successfully synthesized and radiolabeled with (64)Cu and (18)F-AlF. (64)Cu- and (18)F-AlF-labeled NODAGA-RM1 demonstrated excellent serum stability and tumor-imaging properties in the in vitro stability assays and in vivo imaging studies. (64)Cu-NODAGA-RM1 exhibited tumor uptake values of 3.3 ± 0.38, 3.0 ± 0.76, and 3.5 ± 1.0 percentage injected dose per gram of tissue (%ID/g) at 0.5, 1.5, and 4 h after injection, respectively. (18)F-AlF-NODAGA-RM1 exhibited tumor uptake values of 4.6 ± 1.5, 4.0 ± 0.87, and 3.9 ± 0.48 %ID/g at 0.5, 1, and 2 h, respectively.The high-stability, efficient tumor uptake and optimal pharmacokinetic properties highlight (18)F-AlF-NODAGA-RM1 as a probe with great potential and clinical application for the PET imaging of prostate cancer.

    View details for DOI 10.2967/jnumed.113.121533

    View details for Web of Science ID 000328013000018

    View details for PubMedID 24198391

  • Ischemic Postconditioning-Mediated miRNA-21 Protects against Cardiac ischemia/reperfusion Injury via PTEN/Akt Pathway PLOS ONE Tu, Y., Wan, L., Fan, Y., Wang, K., Bu, L., Huang, T., Cheng, Z., Shen, B. 2013; 8 (10)


    Ischemic postconditioning (IPost) protects the reperfused heart from infarction which has drawn much attention recently. However, studies to date have rarely investigated the role of microRNAs (miRNAs) in IPost. The aims of this study were to investigate whether miR-21 is involved in the protective effect of IPost against myocardial ischemia-reperfusion (I/R) injury and disclose the potential molecular mechanisms involved.We found that miR-21 was remarkably up-regulated in mouse hearts after IPost. To determine the protective role of IPost-induced miR-21 up-regulation, the mice were divided into the following four groups: I/R group; I/R+IPost group (I/R mice treated with IPost); Antagomir-21+IPost+I/R group (I/R mice treated with anagomir-21 and IPost); Scramble+IPost+I/R group (I/R mice treated with scramble and IPost). The results showed IPost could reduce I/R injury-induced infarct size of the left ventricle, improve cardiac function, and prevent myocardial apoptosis, while knockdown of miR-21 with antagomir-21 could reverse these protective effects of IPost against mouse I/R injury. Furthermore, we confirmed that miR-21 plays a protective role in myocardial apoptosis through PTEN/Akt signaling pathway, which was abrogated by the PI3K inhibitor LY294002. The protective effect of miR-21 on myocardial apoptosis was further revealed in mouse hearts after IPost treatment in vivo.Our data clearly demonstrate that miR-21 is involved in IPost-mediated cardiac protection against I/R injury and dysfunction through the PTEN/Akt signaling pathway in vivo. Identifying the beneficial roles of IPost-regulated miRNAs in cardiac protection, which may be a rational target selection for ischemic cardioprotection.

    View details for DOI 10.1371/journal.pone.0075872

    View details for Web of Science ID 000325483600025

    View details for PubMedID 24098402

  • Impact of a Multiple Mice Holder on Quantitation of High-Throughput MicroPET Imaging With and Without Ct Attenuation Correction. Molecular imaging and biology Habte, F., Ren, G., Doyle, T. C., Liu, H., Cheng, Z., Paik, D. S. 2013; 15 (5): 569-575


    PURPOSE: The aim of this study is to evaluate the impact of scanning multiple mice simultaneously on image quantitation, relative to single mouse scans on both a micro-positron emission tomography/computed tomography (microPET/CT) scanner (which utilizes CT-based attenuation correction to the PET reconstruction) and a dedicated microPET scanner using an inexpensive mouse holder "hotel." METHODS: We developed a simple mouse holder made from common laboratory items that allows scanning multiple mice simultaneously. It is also compatible with different imaging modalities to allow multiple mice and multi-modality imaging. For this study, we used a radiotracer ((64)Cu-GB170) with a relatively long half-life (12.7 h), selected to allow scanning at times after tracer uptake reaches steady state. This also reduces the effect of decay between sequential imaging studies, although the standard decay corrections were performed. The imaging was also performed using a common tracer, 2-deoxy-2-[(18) F]fluoro-D-glucose (FDG), although the faster decay and faster pharmacokinetics of FDG may introduce greater biological variations due to differences in injection-to-scan timing. We first scanned cylindrical mouse phantoms (50 ml tubes) both in a groups of four at a time (multiple mice mode) and then individually (single mouse mode), using microPET/CT and microPET scanners to validate the process. Then, we imaged a first set of four mice with subcutaneous tumors (C2C12Ras) in both single- and multiple-mice imaging modes. Later, a second set of four normal mice were injected with FDG and scanned 1 h post-injection. Immediately after completion of the scans, ex vivo biodistribution studies were performed on all animals to provide a "gold-standard" to compare quantitative values obtained from PET. A semi-automatic threshold-based region of interest tool was used to minimize operator variability during image analysis. RESULTS: Phantom studies showed less than 4.5 % relative error difference between the single- and multiple-mice imaging modes of PET imaging with CT-based attenuation correction and 18.4 % without CT-based attenuation correction. In vivo animal studies (n = 4) showed <5 % (for (64)Cu, p > 0.686) and <15 % (for FDG, p > 0.4 except for brain image data p = 0.029) relative mean difference with respect to percent injected dose per gram (%ID/gram) between the single- and multiple-mice microPET imaging mode when CT-based attenuation correction is performed. Without CT-based attenuation correction, we observed relative mean differences of about 11 % for (64)Cu and 15 % for FDG. CONCLUSION: Our results confirmed the potential use of a microPET/CT scanner for multiple mice simultaneous imaging without significant sacrifice in quantitative accuracy as well as in image quality. Thus, the use of the mouse "hotel" is an aid to increasing instrument throughput on small animal scanners with minimal loss of quantitative accuracy.

    View details for DOI 10.1007/s11307-012-0602-y

    View details for PubMedID 23479323

  • Optical Image-Guided Cancer Therapy CURRENT PHARMACEUTICAL BIOTECHNOLOGY Bu, L., Ma, X., Tu, Y., Shen, B., Cheng, Z. 2013; 14 (8): 723-732
  • A Novel Aliphatic F-18-Labeled Probe for PET Imaging of Melanoma MOLECULAR PHARMACEUTICS Liu, H., Liu, S., Miao, Z., Jiang, H., Deng, Z., Hong, X., Cheng, Z. 2013; 10 (9): 3384-3391

    View details for DOI 10.1021/mp400225s

    View details for Web of Science ID 000326128700012

  • Lu-177-labeled RGD-BBN heterodimeric peptide for targeting prostate carcinoma NUCLEAR MEDICINE COMMUNICATIONS Jiang, L., Miao, Z., Liu, H., Ren, G., Bao, A., Cutler, C. S., Shi, H., Cheng, Z. 2013; 34 (9): 909-914
  • Evaluation of Zr-89-rituximab Tracer by Cerenkov Luminescence Imaging and Correlation with PET in a Humanized Transgenic Mouse Model to Image NHL MOLECULAR IMAGING AND BIOLOGY Natarajan, A., Habte, F., Liu, H., Sathirachinda, A., Hu, X., Cheng, Z., Nagamine, C. M., Gambhir, S. S. 2013; 15 (4): 468-475


    PURPOSE: This research aimed to study the use of Cerenkov luminescence imaging (CLI) for non-Hodgkin's lymphoma (NHL) using (89)Zr-rituximab positron emission tomography (PET) tracer with a humanized transgenic mouse model that expresses human CD20 and the correlation of CLI with PET. PROCEDURES: Zr-rituximab (2.6 MBq) was tail vein-injected into transgenic mice that express the human CD20 on their B cells (huCD20TM). One group (n = 3) received 2 mg/kg pre-dose (blocking) of cold rituximab 2 h prior to tracer; a second group (n = 3) had no pre-dose (non-blocking). CLI was performed using a cooled charge-coupled device optical imager. We also performed PET imaging and ex vivo studies in order to confirm the in vivo CLI results. At each time point (4, 24, 48, 72, and 96 h), two groups of mice were imaged in vivo and ex vivo with CLI and PET, and at 96 h, organs were measured by gamma counter. RESULTS: huCD20 transgenic mice injected with (89)Zr-rituximab demonstrated a high-contrast CLI image compared to mice blocked with a cold dose. At various time points of 4-96 h post-radiotracer injection, the in vivo CLI signal intensity showed specific uptake in the spleen where B cells reside and, hence, the huCD20 biomarker is present at very high levels. The time-activity curve of dose decay-corrected CLI intensity and percent injected dose per gram of tissue of PET uptake in the spleen were increased over the time period (4-96 h). At 96 h, the (89)Zr-rituximab uptake ratio (non-blocking vs blocking) counted (mean ± standard deviation) for the spleen was 1.5 ± 0.6 for CLI and 1.9 ± 0.3 for PET. Furthermore, spleen uptake measurements (non-blocking and blocking of all time points) of CLI vs PET showed good correlation (R (2) = 0.85 and slope = 0.576), which also confirmed the corresponding correlations parameter value (R (2) = 0.834 and slope = 0.47) obtained for ex vivo measurements. CONCLUSIONS: CLI and PET of huCD20 transgenic mice injected with (89)Zr-rituximab demonstrated that the tracer was able to target huCD20-expressing B cells. The in vivo and ex vivo tracer uptake corresponding to the CLI radiance intensity from the spleen is in good agreement with PET. In this report, we have validated the use of CLI with PET for NHL imaging in huCD20TM.

    View details for DOI 10.1007/s11307-013-0624-0

    View details for Web of Science ID 000321972500014

    View details for PubMedID 23471750

  • 18F-fluorobenzoate-labeled cystine knot peptides for PET imaging of integrin avß6. Journal of nuclear medicine : official publication, Society of Nuclear Medicine Hackel, B. J., Kimura, R. H., Miao, Z., Liu, H., Sathirachinda, A., Cheng, Z., Chin, F. T., Gambhir, S. S. 2013; 54 (7): 1101-1105


    Integrin αvβ6 is a cell surface receptor minimally expressed by healthy tissue but elevated in lung, colon, skin, ovarian, cervical, and pancreatic cancers. A molecular PET agent for integrin αvβ6 could provide significant clinical utility by facilitating both cancer staging and treatment monitoring to more rapidly identify an effective therapeutic approach. METHODS: Here, we evaluated 2 cystine knot peptides, R01 and S02, previously engineered with a 3-6 nM affinity for integrin αvβ6, for (18)F radiolabeling and PET imaging of BxPC3 pancreatic adenocarcinoma xenografts in mice. Cystine knot peptides were labeled with N-succinimidyl-4-(18)F-fluorobenzoate and evaluated for binding affinity and serum stability. Peptides conjugated with (18)F-fluorobenzoate (2-3 MBq) were injected via the tail vein into nude mice xenografted with BxPC3 (integrin αvβ6-positive) or 293 (integrin αvβ6-negative) tumors. Small-animal PET scans were acquired at 0.5, 1, and 2 h after injection. Ex vivo γ-counting of dissected tissues was performed at 0.5 and 2 h. RESULTS: (18)F-fluorobenzoate peptides were produced in 93% ((18)F-fluorobenzoate-R01) and 99% ((18)F-fluorobenzoate-S02) purity. (18)F-fluorobenzoate-R01 and (18)F-fluorobenzoate-S02 had affinities of 1.1 ± 0.2 and 0.7 ± 0.4 nM, respectively, and were 87% and 94%, respectively, stable in human serum at 37°C for 2 h. (18)F-fluorobenzoate-R01 and (18)F-fluorobenzoate-S02 exhibited 2.3 ± 0.6 and 1.3 ± 0.4 percentage injected dose per gram (%ID/g), respectively, in BxPC3 xenografted tumors at 0.5 h (n = 4-5). Target specificity was confirmed by low tumor uptake in integrin αvβ6-negative 293 tumors (1.4 ± 0.6 and 0.5 ± 0.2 %ID/g, respectively, for (18)F-fluorobenzoate-R01 and (18)F-fluorobenzoate-S02; both P < 0.05; n = 3-4) and low muscle uptake (3.1 ± 1.0 and 2.7 ± 0.4 tumor to muscle for (18)F-fluorobenzoate-R01 and (18)F-fluorobenzoate-S02, respectively). Small-animal PET data were corroborated by ex vivo γ-counting of dissected tissues, which demonstrated low uptake in nontarget tissues with only modest kidney uptake (9.2 ± 3.3 and 1.9 ± 1.2 %ID/g, respectively, at 2 h for (18)F-fluorobenzoate-R01 and (18)F-fluorobenzoate-S02; n = 8). Uptake in healthy pancreas was low (0.3% ± 0.1% for (18)F-fluorobenzoate-R01 and 0.03% ± 0.01% for (18)F-fluorobenzoate-S02; n = 8). CONCLUSION: These cystine knot peptide tracers, in particular (18)F-fluorobenzoate-R01, show translational promise for molecular imaging of integrin αvβ6 overexpression in pancreatic and other cancers.

    View details for DOI 10.2967/jnumed.112.110759

    View details for PubMedID 23670900

  • First (18)F-labeled ligand for PET imaging of uPAR: In vivo studies in human prostate cancer xenografts. Nuclear medicine and biology Persson, M., Liu, H., Madsen, J., Cheng, Z., Kjaer, A. 2013; 40 (5): 618-624


    Urokinase-type plasminogen activator receptor (uPAR) is overexpressed in human prostate cancer and uPAR has been found to be associated with metastatic disease and poor prognosis. AE105 is a small linear peptide with high binding affinity to uPAR. We synthesized an N-terminal NOTA-conjugated version (NOTA-AE105) for development of the first (18)F-labeled uPAR positron-emission-tomography PET ligand using the Al(18)F radiolabeling method. In this study, the potential of (18)F-AlF-NOTA-AE105 to specifically target uPAR-positive prostate tumors was investigated.NOTA-conjugated AE105 was synthesized and radiolabeled with (18)F-AlF according to a recently published optimized protocol. The labeled product was purified by reverse phase high performance liquid chromatography RP-HPLC. The tumor targeting properties were evaluated in mice with subcutaneously inoculated PC-3 xenografts using small animal PET and ex vivo biodistribution studies. uPAR-binding specificity was studied by coinjection of an excess of a uPAR antagonist peptide AE105 analogue (AE152).NOTA-AE105 was labeled with (18)F-AlF in high radiochemical purity (>92%) and yield (92.7%) and resulted in a specific activity of greater than 20GBq/μmol. A high and specific tumor uptake was found. At 1h post injection, the uptake of (18)F-AlF-NOTA-AE105 in PC-3 tumors was 4.22±0.13%ID/g. uPAR-binding specificity was demonstrated by a reduced uptake of (18)F-AlF-NOTA-AE105 after coinjection of a blocking dose of uPAR antagonist at all three time points investigated. Good tumor-to-background ratio was observed with small animal PET and confirmed in the biodistribution analysis. Ex vivo uPAR expression analysis on extracted tumors confirmed human uPAR expression that correlated close with tumor uptake of (18)F-AlF-NOTA-AE105.The first (18)F-labeled uPAR PET ligand, (18)F-AlF-NOTA-AE105, has successfully been prepared and effectively visualized noninvasively uPAR positive prostate cancer. The favorable in vivo kinetics and easy production method facilitate its future clinical translation for identification of prostate cancer patients with an invasive phenotype and poor prognosis.

    View details for DOI 10.1016/j.nucmedbio.2013.03.001

    View details for PubMedID 23602763

  • Image-guided resection of malignant gliomas using ?uorescent nanoparticles. Wiley interdisciplinary reviews. Nanomedicine and nanobiotechnology Su, X., Cheng, K., Wang, C., Xing, L., Wu, H., Cheng, Z. 2013; 5 (3): 219-232


    Intraoperative fluorescence imaging especially near-infrared fluorescence (NIRF) imaging has the potential to revolutionize neurosurgery by providing high sensitivity and real-time image guidance to surgeons for defining gliomas margins. Fluorescence probes including targeted nanoprobes are expected to improve the specificity and selectivity for intraoperative fluorescence or NIRF tumor imaging. The main focus of this article is to provide a brief overview of intraoperative fluorescence imaging systems and probes including fluorescein sodium, 5-aminolevulinic acid, dye-containing nanoparticles, and targeted NIRF nanoprobes for their applications in image-guided resection of malignant gliomas. Moreover, photoacoustic imaging is a promising molecular imaging modality, and its potential applications for brain tumor imaging are also briefly discussed.

    View details for DOI 10.1002/wnan.1212

    View details for PubMedID 23378052

  • Fluorine-18 labeling by click chemistry: Multiple probes in one pot APPLIED RADIATION AND ISOTOPES Jia, L., Cheng, Z., Shi, L., Li, J., Wang, C., Jiang, D., Zhou, W., Meng, H., Qi, Y., Cheng, D., Zhang, L. 2013; 75: 64-70


    Click chemistry has been widely applied in drug development including radiopharmaceuticals and has shown great advantages. Here we reported a novel strategy for rapid preparation of multiple (18)F labeled PET probes in one pot using the 'Click Reaction' of Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition of terminal alkynes and organic azides (CuAAC). Preliminary results showed its high efficiency and potential for speeding up the preclinical screening of PET probes.

    View details for DOI 10.1016/j.apradiso.2013.01.033

    View details for Web of Science ID 000317558900012

    View details for PubMedID 23455406

  • Affibody modified and radiolabeled gold-Iron oxide hetero-nanostructures for tumor PET, optical and MR imaging BIOMATERIALS Yang, M., Cheng, K., Qi, S., Liu, H., Jiang, Y., Jiang, H., Li, J., Chen, K., Zhang, H., Cheng, Z. 2013; 34 (11): 2796-2806


    A highly monodispersed hetero-nanostructure with two different functional nanomaterials (gold (Au) and iron oxide (Fe(3)O(4,) IO)) within one structure was successfully developed as Affibody based trimodality nanoprobe (positron emission tomography, PET; optical imaging; and magnetic resonance imaging, MRI) for imaging of epidermal growth factor receptor (EGFR) positive tumors. Unlike other regular nanostructures with a single component, the Au-IO hetero-nanostructures (Au-IONPs) with unique chemical and physical properties have capability to combine several imaging modalities together to provide complementary information. The IO component within hetero-nanostructures serve as a T(2) reporter for MRI; and gold component serve as both optical and PET reporters. Moreover, such hetero-nanoprobes could provide a robust nano-platform for surface-specific modification with both targeting molecules (anti-EGFR Affibody protein) and PET imaging reporters (radiometal (64)Cu chelators) in highly efficient and reliable manner. In vitro and in vivo study showed that the resultant nanoprobe provided high specificity, sensitivity, and excellent tumor contrast for both PET and MRI imaging in the human EGFR-expressing cells and tumors. Our study data also highlighted the EGFR targeting efficiency of hetero-nanoparticles and the feasibility for their further theranostic applications.

    View details for DOI 10.1016/j.biomaterials.2013.01.014

    View details for Web of Science ID 000315748200022

    View details for PubMedID 23343632

    View details for PubMedCentralID PMC3563754

  • Development of F-18-Labeled Picolinamide Probes for PET Imaging of Malignant Melanoma JOURNAL OF MEDICINAL CHEMISTRY Liu, H., Liu, S., Miao, Z., Deng, Z., Shen, B., Hong, X., Cheng, Z. 2013; 56 (3): 895-901


    Melanoma is an aggressive skin cancer with worldwide increasing incidence. Development of positron emission tomography (PET) probes for early detection of melanoma is critical for improving the survival rate of melanoma patients. In this research, (18)F-picolinamide-based PET probes were prepared by direct radiofluorination of the bromopicolinamide precursors using no-carrier-added (18)F-fluoride. The resulting probes, (18)F-1, (18)F-2 and (18)F-3, were then evaluated in vivo by small animal PET imaging and biodistribution studies in C57BL/6 mice bearing B16F10 murine melanoma tumors. Noninvasive small animal PET studies demonstrated excellent tumor imaging contrasts for all probes, while (18)F-2 showed higher tumor to muscle ratios than (18)F-1 and (18)F-3. Furthermore, (18)F-2 demonstrated good in vivo stability as evidenced by the low bone uptake in biodistribution studies. Collectively, these findings suggest (18)F-2 as a highly promising PET probe for translation into clinical detection of melanoma.

    View details for DOI 10.1021/jm301740k

    View details for Web of Science ID 000315182100023

    View details for PubMedID 23301672

    View details for PubMedCentralID PMC3586277

  • A novel radiofluorinated agouti-related protein for tumor angiogenesis imaging AMINO ACIDS Jiang, H., Moore, S. J., Liu, S., Liu, H., Miao, Z., Cochran, F. V., Liu, Y., Tian, M., Cochran, J. R., Zhang, H., Cheng, Z. 2013; 44 (2): 673-681


    A novel protein scaffold based on the cystine knot domain of the agouti-related protein (AgRP) has been used to engineer mutants that can bind to the α(v)β(3) integrin receptor with high affinity and specificity. In the current study, an (18)F-labeled AgRP mutant (7C) was prepared and evaluated as a positron emission tomography (PET) probe for imaging tumor angiogenesis. AgRP-7C was synthesized by solid phase peptide synthesis and site-specifically conjugated with 4-nitrophenyl 2-(18/19)F-fluoropropionate ((18/19)F-NFP) to produce the fluorinated peptide, (18/19)F-FP-AgRP-7C. Competition binding assays were used to measure the relative affinities of AgRP-7C and (19)F-FP-AgRP-7C to human glioblastoma U87MG cells that overexpress α(v)β(3) integrin. In addition, biodistribution, metabolic stability, and small animal PET imaging studies were conducted with (18)F-FP-AgRP-7C using U87MG tumor-bearing mice. Both AgRP-7C and (19)F-FP-AgRP-7C specifically competed with (125)I-echistatin for binding to U87MG cells with half maximal inhibitory concentration (IC(50)) values of 9.40 and 8.37 nM, respectively. Non-invasive small animal PET imaging revealed that (18)F-FP-AgRP-7C exhibited rapid and good tumor uptake (3.24 percentage injected dose per gram [% ID/g] at 0.5 h post injection [p.i.]). The probe was rapidly cleared from the blood and from most organs, resulting in excellent tumor-to-normal tissue contrasts. Tumor uptake and rapid clearance were further confirmed with biodistribution studies. Furthermore, co-injection of (18)F-FP-AgRP-7C with a large molar excess of blocking peptide c(RGDyK) significantly inhibited tumor uptake in U87MG xenograft models, demonstrating the integrin-targeting specificity of the probe. Metabolite assays showed that the probe had high stability, making it suitable for in vivo applications. (18)F-FP-AgRP-7C exhibits promising in vivo properties such as rapid tumor targeting, good tumor uptake, and excellent tumor-to-normal tissue ratios, and warrants further investigation as a novel PET probe for imaging tumor angiogenesis.

    View details for DOI 10.1007/s00726-012-1391-y

    View details for Web of Science ID 000313794600036

    View details for PubMedID 22945905

  • Molecular imaging of hepatocellular carcinoma xenografts with epidermal growth factor receptor targeted affibody probes. BioMed research international Zhao, P., Yang, X., Qi, S., Liu, H., Jiang, H., Hoppmann, S., Cao, Q., Chua, M., So, S. K., Cheng, Z. 2013; 2013: 759057-?


    Hepatocellular carcinoma (HCC) is a highly aggressive and lethal cancer. It is typically asymptomatic at the early stage, with only 10%-20% of HCC patients being diagnosed early enough for appropriate surgical treatment. The delayed diagnosis of HCC is associated with limited treatment options and much lower survival rates. Therefore, the early and accurate detection of HCC is crucial to improve its currently dismal prognosis. The epidermal growth factor receptor (EGFR) has been reported to be involved in HCC tumorigenesis and to represent an attractive target for HCC imaging and therapy. In this study, an affibody molecule, Ac-Cys-ZEGFR:1907, targeting the extracellular domain of EGFR, was used for the first time to assess its potential to detect HCC xenografts. By evaluating radio- or fluorescent-labeled Ac-Cys-ZEGFR:1907 as a probe for positron emission tomography (PET) or optical imaging of HCC, subcutaneous EGFR-positive HCC xenografts were found to be successfully imaged by the PET probe. Thus, affibody-based PET imaging of EGFR provides a promising approach for detecting HCC in vivo.

    View details for DOI 10.1155/2013/759057

    View details for PubMedID 23710458

  • MicroRNA-22 Downregulation by Atorvastatin in a Mouse Model of Cardiac Hypertrophy: a new Mechanism for Antihypertrophic Intervention CELLULAR PHYSIOLOGY AND BIOCHEMISTRY Tu, Y., Wan, L., Bu, L., Zhao, D., Dong, D., Huang, T., Cheng, Z., Shen, B. 2013; 31 (6): 997-1008


    Growing evidence shows that microRNAs (miRNAs) are involved in various cardiac processes including cardiac hypertrophy. However, the modulation of miRNA by pharmacological intervention in cardiomyocyte hypertrophy has not been disclosed yet. methods: We constructed neonatal rat cardiomyocyte hypertrophy induced by angiotensin II stimulation and subjected to cardiomyocyte immunochemistry, qRT-PCR and immunoblotting analysis. In addition, we constructed the mouse cardiac hypertrophy using angomir-22 stimulation and demonstrated the potential antihypertrophic mechnism of atorvastatin.The results showed that a collection of miRNAs were aberrantly expressed in hypertrophic cardiomyocytes induced by angiotensin II stimulation. In addition, overexpression of miR-22 was found in angiotensin II-induced hypertrophic cardiomyocytes, whereas administration of atorvastatin could reverse the upregulation of miRNA-22 nearly back to the control level. Furthermore, up-regulation of miRNA-22 in cardiomyocytes in vitro and in vivo could induce cardiac hypertrophy, which could suppress the protein level of phosphatase and tensin homolog deleted on chromosome ten (PTEN). Concomitantly, the production of ANP, BNP and β-MHC was enhanced and cardiomyocyte size was increased. However, atorvastatin could markedly knockdown miRNA-22 expression and reverse these changes in cardiomyocytes. These results suggest that the contribution of atrovastatin to cardiomyocyte hypertrophy may be involved in downregulation of miRNA-22 expression, which modulates the activity of PTEN in cardiomyocyte hypertrophy. conclusion: This study demonstrates for the first time the modulation of miRNA-22 can be achieved by pharmacological intervention. The data generated from this study provides a rationale for the development of miRNA-based strategies for antihypertrophic treatment.

    View details for DOI 10.1159/000350117

    View details for Web of Science ID 000322727700024

    View details for PubMedID 23860036

  • 177Lu-labeled RGD-BBN heterodimeric peptide for targeting prostate carcinoma. Nuclear medicine communications Jiang, L. n., Miao, Z. n., Liu, H. n., Ren, G. n., Bao, A. n., Cutler, C. S., Shi, H. n., Cheng, Z. n. 2013; 34 (9): 909–14


    Radiolabeled Arg-Gly-Asp (RGD) and bombesin (BBN) heterodimers have been investigated for dual targeting of tumor integrin αvβ3 receptors and gastrin-releasing peptide receptors. The goal of this study was to evaluate the potential use of a Lu-labeled RGD-BBN heterodimer for targeted prostate cancer therapy.A 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-conjugated RGD-BBN peptide (DO3A-RGD-BBN) was radiolabeled with Lu and purified by high-performance liquid chromatography. The in-vivo biodistribution study of Lu-DO3A-RGD-BBN was carried out in mice bearing human prostate cancer PC3 xenografts. The receptor-targeting specificity of the radiolabeled peptide was assayed by injecting the tracer with the unlabeled RGD-BBN peptide. Radiation absorbed doses in adult male patients, based on biodistribution data from mice, were also calculated.DO3A-RGD-BBN peptides were successfully labeled with Lu, and high radiochemical purity (>95%) could be achieved after high-performance liquid chromatography purification. In human PC3 xenograft-bearing mice, the tumor accumulation of Lu-DO3A-RGD-BBN was 5.88±1.12, 2.77±0.30, 2.04±0.19, and 1.18±0.19%ID/g at 0.5, 2, 24, and 48 h, respectively. With rapid clearance from normal tissues, the radiolabeled probe displayed high tumor-to-blood and tumor-to-muscle ratios. On calculating the radiation absorbed doses for Lu-DO3A-RGD-BBN, we found that the prostate tumor and the pancreas were the organs receiving the highest radiation absorbed doses.Dual integrin αvβ3 and GPRP-targeted agent Lu-DO3A-RGD-BBN shows excellent prostate cancer-targeting ability, and it is worthy of further evaluation for prostate cancer-targeted therapy.

    View details for DOI 10.1097/MNM.0b013e328362d2b6

    View details for PubMedID 23708872

  • Tyrosinase as a multifunctional reporter gene for Photoacoustic/MRI/PET triple modality molecular imaging. Scientific reports Qin, C., Cheng, K., Chen, K., Hu, X., Liu, Y., Lan, X., Zhang, Y., Liu, H., Xu, Y., Bu, L., Su, X., Zhu, X., Meng, S., Cheng, Z. 2013; 3: 1490-?


    Development of reporter genes for multimodality molecular imaging is highly important. In contrast to the conventional strategies which have focused on fusing several reporter genes together to serve as multimodal reporters, human tyrosinase (TYR)--the key enzyme in melanin production--was evaluated in this study as a stand-alone reporter gene for in vitro and in vivo photoacoustic imaging (PAI), magnetic resonance imaging (MRI) and positron emission tomography (PET). Human breast cancer cells MCF-7 transfected with a plasmid that encodes TYR (named as MCF-7-TYR) and non-transfected MCF-7 cells were used as positive and negative controls, respectively. Melanin targeted N-(2-(diethylamino)ethyl)-18F-5-fluoropicolinamide was used as a PET reporter probe. In vivo PAI/MRI/PET imaging studies showed that MCF-7-TYR tumors achieved significant higher signals and tumor-to-background contrasts than those of MCF-7 tumor. Our study demonstrates that TYR gene can be utilized as a multifunctional reporter gene for PAI/MRI/PET both in vitro and in vivo.

    View details for DOI 10.1038/srep01490

    View details for PubMedID 23508226

  • Continuous sensing of tumor-targeted molecular probes with a vertical cavity surface emitting laser-based biosensor JOURNAL OF BIOMEDICAL OPTICS Parashurama, N., O'Sullivan, T. D., de la Zerda, A., El Kalassi, P., Cho, S., Liu, H., Teed, R., Levy, H., Rosenberg, J., Cheng, Z., Levi, O., Harris, J. S., Gambhir, S. S. 2012; 17 (11)


    Molecular optical imaging is a widespread technique for interrogating molecular events in living subjects. However, current approaches preclude long-term, continuous measurements in awake, mobile subjects, a strategy crucial in several medical conditions. Consequently, we designed a novel, lightweight miniature biosensor for in vivo continuous optical sensing. The biosensor contains an enclosed vertical-cavity surface-emitting semiconductor laser and an adjacent pair of near-infrared optically filtered detectors. We employed two sensors (dual sensing) to simultaneously interrogate normal and diseased tumor sites. Having established the sensors are precise with phantom and in vivo studies, we performed dual, continuous sensing in tumor (human glioblastoma cells) bearing mice using the targeted molecular probe cRGD-Cy5.5, which targets αVβ3 cell surface integrins in both tumor neovasculature and tumor. The sensors capture the dynamic time-activity curve of the targeted molecular probe. The average tumor to background ratio after signal calibration for cRGD-Cy5.5 injection is approximately 2.43±0.95 at 1 h and 3.64±1.38 at 2 h (N=5 mice), consistent with data obtained with a cooled charge coupled device camera. We conclude that our novel, portable, precise biosensor can be used to evaluate both kinetics and steady state levels of molecular probes in various disease applications.

    View details for DOI 10.1117/1.JBO.17.11.117004

    View details for Web of Science ID 000314502700046

    View details for PubMedID 23123976

    View details for PubMedCentralID PMC3595658

  • Cerenkov Luminescence Imaging (CLI) for Cancer Therapy Monitoring JOVE-JOURNAL OF VISUALIZED EXPERIMENTS Xu, Y., Liu, H., Chang, E., Jiang, H., Cheng, Z. 2012


    In molecular imaging, positron emission tomography (PET) and optical imaging (OI) are two of the most important and thus most widely used modalities. PET is characterized by its excellent sensitivity and quantification ability while OI is notable for non-radiation, relative low cost, short scanning time, high throughput, and wide availability to basic researchers. However, both modalities have their shortcomings as well. PET suffers from poor spatial resolution and high cost, while OI is mostly limited to preclinical applications because of its limited tissue penetration along with prominent scattering optical signals through the thickness of living tissues. Recently a bridge between PET and OI has emerged with the discovery of Cerenkov Luminescence Imaging (CLI). CLI is a new imaging modality that harnesses Cerenkov Radiation (CR) to image radionuclides with OI instruments. Russian Nobel laureate Alekseyevich Cerenkov and his colleagues originally discovered CR in 1934. It is a form of electromagnetic radiation emitted when a charged particle travels at a superluminal speed in a dielectric medium. The charged particle, whether positron or electron, perturbs the electromagnetic field of the medium by displacing the electrons in its atoms. After passing of the disruption photons are emitted as the displaced electrons return to the ground state. For instance, one (18)F decay was estimated to produce an average of 3 photons in water. Since its emergence, CLI has been investigated for its use in a variety of preclinical applications including in vivo tumor imaging, reporter gene imaging, radiotracer development, multimodality imaging, among others. The most important reason why CLI has enjoyed much success so far is that this new technology takes advantage of the low cost and wide availability of OI to image radionuclides, which used to be imaged only by more expensive and less available nuclear imaging modalities such as PET. Here, we present the method of using CLI to monitor cancer drug therapy. Our group has recently investigated this new application and validated its feasibility by a proof-of-concept study. We demonstrated that CLI and PET exhibited excellent correlations across different tumor xenografts and imaging probes. This is consistent with the overarching principle of CR that CLI essentially visualizes the same radionuclides as PET. We selected Bevacizumab (Avastin; Genentech/Roche) as our therapeutic agent because it is a well-known angiogenesis inhibitor. Maturation of this technology in the near future can be envisioned to have a significant impact on preclinical drug development, screening, as well as therapy monitoring of patients receiving treatments.

    View details for DOI 10.3791/4341

    View details for Web of Science ID 000209226000031

  • Novel, Cysteine-Modified Chelation Strategy for the Incorporation of [M-I(CO)(3)](+) (M = Re, Tc-99m) in an alpha-MSH Peptide BIOCONJUGATE CHEMISTRY Jiang, H., Kasten, B. B., Liu, H., Qi, S., Liu, Y., Tian, M., Barnes, C. L., Zhang, H., Cheng, Z., Benny, P. D. 2012; 23 (11): 2300-2312


    Engineering peptide-based targeting agents with residues for site-specific and stable complexation of radionuclides is a highly desirable strategy for producing diagnostic and therapeutic agents for cancer and other diseases. In this report, a model N-S-N(Py) ligand (3) and a cysteine-derived α-melanocyte stimulating hormone (α-MSH) peptide (6) were used as novel demonstrations of a widely applicable chelation strategy for incorporation of the [M(I)(CO)(3)](+) (M = Re, (99m)Tc) core into peptide-based molecules for radiopharmaceutical applications. The structural details of the core ligand-metal complexes as model systems were demonstrated by full chemical characterization of fac-[Re(I)(CO)(3)(N,S,N(Py)-3)](+) (4) and comparative high-performance liquid chromatography (HPLC) analysis between 4 and [(99m)Tc(I)(CO)(3)(N,S,N(Py)-3)](+) (4a). The α-MSH analogue bearing the N-S-N(Py) chelate on a modified cysteine residue (6) was generated and complexed with [M(I)(CO)(3)](+) to confirm the chelation strategy's utility when applied in a peptide-based targeting agent. Characterization of the Re(I)(CO)(3)-6 peptide conjugate (7) confirmed the efficient incorporation of the metal center, and the (99m)Tc(I)(CO)(3)-6 analogue (7a) was explored as a potential single photon emission computed tomography (SPECT) compound for imaging the melanocortin 1 receptor (MC1R) in melanoma. Peptide 7a showed excellent radiolabeling yields and in vitro stability during amino acid challenge and serum stability assays. In vitro B16F10 melanoma cell uptake of 7a reached a modest value of 2.3 ± 0.08% of applied activity at 2 h at 37 °C, while this uptake was significantly reduced by coincubation with a nonlabeled α-MSH analogue, NAPamide (3.2 μM) (P < 0.05). In vivo SPECT/X-ray computed tomography (SPECT/CT) imaging and biodistribution of 7a were evaluated in a B16F10 melanoma xenografted mouse model. SPECT/CT imaging clearly visualized the tumor at 1 h post injection (p.i.) with high tumor-to-background contrast. Blocking studies with coinjected NAPamide (10 mg per kg of mouse body weight) confirmed the in vivo specificity of 7a for MC1R-positive tumors. Biodistribution results with 7a yielded a moderate tumor uptake of 1.20 ± 0.09 percentage of the injected radioactive dose per gram of tissue (% ID/g) at 1 h p.i. Relatively high uptake of 7a was also seen in the kidneys and liver at 1 h p.i. (6.55 ± 0.36% ID/g and 4.44 ± 0.17% ID/g, respectively), although reduced kidney uptake was seen at 4 h p.i. (3.20 ± 0.48% ID/g). These results demonstrate the utility of the novel [M(I)(CO)(3)](+) chelation strategy when applied in a targeting peptide.

    View details for DOI 10.1021/bc300509k

    View details for Web of Science ID 000311325000017

    View details for PubMedID 23110503

    View details for PubMedCentralID PMC3525672

  • Near Infrared Receptor-Targeted Nanoprobes for Early Diagnosis of Cancers CURRENT MEDICINAL CHEMISTRY Cheng, K., Cheng, Z. 2012; 19 (28): 4767-4785


    The success of detecting cancer at early stages relies greatly on the sensitivity and specificity of in vivo molecular imaging. Optical imaging with near infrared (NIR) luminescent molecular nanoprobes currently attracts much attention because of many advantages of this imaging modality. It provides real time imaging with relatively inexpensive cost, produces images with high sensitivity and spatial resolution, and avoids exposure to ionizing irradiation. Raman spectroscopy/microscopy imaging with surface enhanced Raman scattering (SERS) nanoparticles allows scientists to detect biological events in living cells or organisms in real time and with high sensitivity. The photoacoustic imaging has emerged as a hybrid of optical and ultrasound imaging for sensitive and quantitative tumor detection. Given the recent advances in nanoscience and biomedicine, receptor-targeted NIR nanoprobes promise to improve the cancer early detection with relatively high sensitivity and specificity. We summarize various targeted NIR nanoprobes and their potential applications in cancer targeting and in vivo imaging and discuss the potential of multimodality imaging of NIR nanoprobes. With ongoing efforts to enhance their targeting ability and endow more functions, NIR nanoprobes hold great promise for clinical translation.

    View details for Web of Science ID 000309745800006

    View details for PubMedID 22873665

  • Intraoperative Imaging of Tumors Using Cerenkov Luminescence Endoscopy: A Feasibility Experimental Study JOURNAL OF NUCLEAR MEDICINE Liu, H., Carpenter, C. M., Jiang, H., Pratx, G., Sun, C., Buchin, M. P., Gambhir, S. S., Xing, L., Cheng, Z. 2012; 53 (10): 1579-1584


    Cerenkov luminescence imaging (CLI) is an emerging new molecular imaging modality that is relatively inexpensive, easy to use, and has high throughput. CLI can image clinically available PET and SPECT probes using optical instrumentation. Cerenkov luminescence endoscopy (CLE) is one of the most intriguing applications that promise potential clinical translation. We developed a prototype customized fiberscopic Cerenkov imaging system to investigate the potential in guiding minimally invasive surgical resection.All experiments were performed in a dark chamber. Cerenkov luminescence from (18)F-FDG samples containing decaying radioactivity was transmitted through an optical fiber bundle and imaged by an intensified charge-coupled device camera. Phantoms filled with (18)F-FDG were used to assess the imaging spatial resolution. Finally, mice bearing subcutaneous C6 glioma cells were injected intravenously with (18)F-FDG to determine the feasibility of in vivo imaging. The tumor tissues were exposed, and CLI was performed on the mouse before and after surgical removal of the tumor using the fiber-based imaging system and compared with a commercial optical imaging system.The sensitivity of this particular setup was approximately 45 kBq (1.21 μCi)/300 μL. The 3 smallest sets of cylindric holes in a commercial SPECT phantom were identifiable via this system, demonstrating that the system has a resolution better than 1.2 mm. Finally, the in vivo tumor imaging study demonstrated the feasibility of using CLI to guide the resection of tumor tissues.This proof-of-concept study explored the feasibility of using fiber-based CLE for the detection of tumor tissue in vivo for guided surgery. With further improvements of the imaging sensitivity and spatial resolution of the current system, CLE may have a significant application in the clinical setting in the near future.

    View details for DOI 10.2967/jnumed.111.098541

    View details for Web of Science ID 000309432400017

    View details for PubMedID 22904353

  • The manipulation of natural killer cells to target tumor sites using magnetic nanoparticles BIOMATERIALS Jang, E., Shin, J., Ren, G., Park, M., Cheng, K., Chen, X., Wu, J. C., Sunwoo, J. B., Cheng, Z. 2012; 33 (22): 5584-5592


    The present work demonstrates that Cy5.5 conjugated Fe(3)O(4)/SiO(2) core/shell nanoparticles could allow us to control movement of human natural killer cells (NK-92MI) by an external magnetic field. Required concentration of the nanoparticles for the cell manipulation is as low as ~20 μg Fe/mL. However, the relative ratio of the nanoparticles loaded NK-92MI cells infiltrated into the target tumor site is enhanced by 17-fold by applying magnetic field and their killing activity is still maintained as same as the NK-92MI cells without the nanoparticles. This approach allows us to open alternative clinical treatment with reduced toxicity of the nanoparticles and enhanced infiltration of immunology to the target site.

    View details for DOI 10.1016/j.biomaterials.2012.04.041

    View details for PubMedID 22575830

  • A multimodality reporter gene for monitoring transplanted stem cells NUCLEAR MEDICINE AND BIOLOGY Pei, Z., Lan, X., Cheng, Z., Qin, C., Wang, P., He, Y., Yen, T., Tian, Y., Mghanga, F. P., Zhang, Y. 2012; 39 (6): 813-820


    The aim of this study is to explore the feasibility of a triple-fused reporter gene, termed TGF [herpes simplex virus type 1 thymidine kinase (HSV1-tk), enhanced green fluorescent protein (eGFP) and firefly luciferase (Fluc)], to monitor stem cells using multimodality molecular imaging.A recombinant adenovirus vector carrying the triple-fused reporter gene (Ad5-TGF) was constructed. Bone marrow mesenchymal stem cells (BMSCs) were transfected with different virus titers of Ad5-TGF [multiplicities of infection (MOIs) were 0, 50, 100, 150, 200 and 250]. The mRNA and protein expressions of HSV1-tk, eGFP and Fluc in the transfected BMSCs were evaluated using polymerase chain reaction and Western blot. After the transfection of the BMSCs with different virus titers of Ad5-TGF (MOIs were 25, 50, 75, 100 and 125), their uptake rates of (131)I-FIAU were measured. Whole-body fluorescence, bioluminescence and micro-positron emission tomography (PET) images were acquired 1 day after the transfected BMSCs were injected into the left forelimb of rats.After the transfection with different titers of Ad5-TGF, the positive transfection rate reached a peak (70%) when the MOI was 100. HSV1-tk, eGFP and Fluc mRNA and protein were detected in the Ad5-TGF-transfected BMSCs, which implies their successful transfection and expression. The BMSCs uptake of (131)I-FIAU increased with the adenovirus titer and incubation time and reached a plateau (approximately 5.3%) after 3 h. Strong signals were observed in the injected left forearms in the fluorescence, bioluminescence and micro-PET images.A triple-fused reporter gene, TGF, can be used as a multifunctional molecular probe for multimodality imaging.

    View details for DOI 10.1016/j.nucmedbio.2011.12.014

    View details for Web of Science ID 000307041000009

    View details for PubMedID 22336371

  • Activatable Near-Infrared Fluorescent Probe for In Vivo Imaging of Fibroblast Activation Protein-alpha BIOCONJUGATE CHEMISTRY Li, J., Chen, K., Liu, H., Cheng, K., Yang, M., Zhang, J., Cheng, J. D., Zhang, Y., Cheng, Z. 2012; 23 (8): 1704-1711


    Fibroblast activation protein-alpha (FAPα) is a cell surface glycoprotein which is selectively expressed by tumor-associated fibroblasts in malignant tumors but rarely on normal tissues. FAPα has also been reported to promote tumor growth and invasion and therefore has been of increasing interest as a promising target for designing tumor-targeted drugs and imaging agents. Although medicinal study on FAPα inhibitors has led to the discovery of many FAPα-targeting inhibitors including a drug candidate in a phase II clinical trial, the development of imaging probes to monitor the expression and activity of FAPα in vivo has largely lagged behind. Herein, we report an activatable near-infrared (NIR) fluorescent probe (ANP(FAP)) for in vivo optical imaging of FAPα. The ANP(FAP) consists of a NIR dye (Cy5.5) and a quencher dye (QSY21) which are linked together by a short peptide sequence (KGPGPNQC) specific for FAPα cleavage. Because of the efficient fluorescence resonance energy transfer (FRET) between Cy5.5 and QSY21 in ANP(FAP), high contrast on the NIR fluorescence signal can be achieved after the cleavage of the peptide sequence by FAPα both in vitro and in vivo. In vitro assay on ANP(FAP) indicated the specificity of the probe to FAPα. The in vivo optical imaging using ANP(FAP) showed fast tumor uptake as well as high tumor to background contrast on U87MG tumor models with FAPα expression, while much lower signal and tumor contrast were observed in the C6 tumor without FAPα expression, demonstrating the in vivo targeting specificity of the ANP(FAP). Ex vivo imaging also demonstrated ANP(FAP) had high tumor uptake at 4 h post injection. Collectively, these results indicated that ANP(FAP) could serve as a useful NIR optical probe for early detection of FAPα expressing tumors.

    View details for DOI 10.1021/bc300278r

    View details for Web of Science ID 000307487300021

    View details for PubMedID 22812530

    View details for PubMedCentralID PMC3419799

  • In vivo targeting of HER2-positive tumor using 2-helix affibody molecules AMINO ACIDS Ren, G., Webster, J. M., Liu, Z., Zhang, R., Miao, Z., Liu, H., Gambhir, S. S., Syud, F. A., Cheng, Z. 2012; 43 (1): 405-413


    Molecular imaging of human epidermal growth factor receptor type 2 (HER2) expression has drawn significant attention because of the unique role of the HER2 gene in diagnosis, therapy and prognosis of human breast cancer. In our previous research, a novel cyclic 2-helix small protein, MUT-DS, was discovered as an anti-HER2 Affibody analog with high affinity through rational protein design and engineering. MUT-DS was then evaluated for positron emission tomography (PET) of HER2-positive tumor by labeling with two radionuclides, 68Ga and 18F, with relatively short half-life (t1/2<2 h). In order to fully study the in vivo behavior of 2-helix small protein and demonstrate that it could be a robust platform for labeling with a variety of radionuclides for different applications, in this study, MUT-DS was further radiolabeled with 64Cu or 111In and evaluated for in vivo targeting of HER2-positive tumor in mice. Design 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) conjugated MUT-DS (DOTA-MUT-DS) was chemically synthesized using solid phase peptide synthesizer and I2 oxidation. DOTA-MUT-DS was then radiolabeled with 64Cu or 111In to prepare the HER2 imaging probe (64Cu/111In-DOTA-MUT-DS). Both biodistribution and microPET imaging of the probe were evaluated in nude mice bearing subcutaneous HER2-positive SKOV3 tumors. DOTA-MUT-DS could be successfully synthesized and radiolabeled with 64Cu or 111In. Biodistribution study showed that tumor uptake value of 64Cu or 111In-labeled DOTA-MUT-DS was 4.66±0.38 or 2.17±0.15%ID/g, respectively, in nude mice bearing SKOV3 xenografts (n=3) at 1 h post-injection (p.i.). Tumor-to-blood and tumor-to-muscle ratios for 64Cu-DOTA-MUT-DS were attained to be 3.05 and 3.48 at 1 h p.i., respectively, while for 111In-DOTA-MUT-DS, they were 2.04 and 3.19, respectively. Co-injection of the cold Affibody molecule ZHER2:342 with 64Cu-DOTA-MUT-DS specifically reduced the SKOV3 tumor uptake of the probe by 48%. 111In-DOTA-MUT-DS displayed lower liver uptake at all the time points investigated and higher tumor to blood ratios at 4 and 20 h p.i., when compared with 64Cu-DOTA-MUT-DS. This study demonstrates that the 2-helix protein based probes, 64Cu/111In DOTA-MUT-DS, are promising molecular probes for imaging HER2-positive tumor. Two-helix small protein scaffold holds great promise as a novel and robust platform for imaging and therapy applications.

    View details for DOI 10.1007/s00726-011-1096-7

    View details for Web of Science ID 000305210800041

    View details for PubMedID 21984380

  • PET of EGFR Expression with an F-18-Labeled Affibody Molecule JOURNAL OF NUCLEAR MEDICINE Miao, Z., Ren, G., Liu, H., Qi, S., Wu, S., Cheng, Z. 2012; 53 (7): 1110-1118


    Epidermal growth factor receptor (EGFR) is often overexpressed in a variety of human cancers, and its expression is associated with poor prognosis for many cancer types. However, an accurate technique to noninvasively image EGFR expression in vivo is not available in the clinical setting. In this research, an Affibody analog, anti-EGFR Ac-Cys-Z(EGFR:1907), was successfully site-specifically (18)F-labeled for PET of EGFR expression.The prosthetic group N-[2-(4-(18)F-fluorobenzamido) ethyl] maleimide ((18)F-FBEM) was conjugated to Ac-Cys-Z(EGFR:1907) under mild conditions (pH 7) to produce the probe (18)F-FBEM-Cys-Z(EGFR:1907). The binding affinity and specificity tests of (18)F-FBEM-Cys-Z(EGFR:1907) to EGFR were conducted using A431 cancer cells. Small-animal PET and biodistribution studies were conducted on various mice tumor xenograft models with EGFR overexpression (6 types) after injection of approximately 2.0 MBq of (18)F-FBEM-Cys-Z(EGFR:1907) with or without coinjection of unlabeled Ac-Cys-Z(EGFR:1907) for up to 3 h after injection. A correlation study between (18)F-FBEM-Cys-Z(EGFR:1907) small- animal PET quantification and ex vivo Western blot analysis of tumor EGFR expression was conducted in those 6 types of tumor models.(18)F-FBEM-Cys-Z(EGFR:1907) binds to EGFR with low nanomolar affinity (37 nM) in A431 cells. (18)F-FBEM-Cys-Z(EGFR:1907) rapidly accumulated in the tumor and cleared from most of the normal organs except the liver and kidneys at 3 h after injection, allowing excellent tumor-to-normal tissue contrast to be obtained. In the A431 tumor xenograft model, coinjection of the PET probe with 45 μg of Ac-Cys-Z(EGFR:1907) was able to improve the tumor uptake (3.9 vs. 8.1 percentage of the injected radioactive dose per gram of tissue, at 3 h after injection) and tumor imaging contrast, whereas coinjection with 500 μg of Ac-Cys-Z(EGFR:1907) successfully blocked the tumor uptake significantly (8.1 vs. 1.0 percentage of the injected radioactive dose per gram of tissue, at 3 h after injection, 88% inhibition, P < 0.05). Moderate correlation was found between the tumor tracer uptake at 3 h after injection quantified by PET and EGFR expression levels measured by Western blot assay (P = 0.007, R = 0.59).(18)F-FBEM-Cys-Z(EGFR:1907) is a novel protein scaffold-based PET probe for imaging EGFR overexpression of tumors, and its ability to differentiate tumors with high and low EGFR expression in vivo holds promise for future clinical translation.

    View details for DOI 10.2967/jnumed.111.100842

    View details for Web of Science ID 000306164600028

    View details for PubMedID 22689926

  • Assessment and comparison of magnetic nanoparticles as MRI contrast agents in a rodent model of human hepatocellular carcinoma CONTRAST MEDIA & MOLECULAR IMAGING Bu, L., Xie, J., Chen, K., Huang, J., Aguilar, Z. P., Wang, A., Sun, K. W., Chua, M., So, S., Cheng, Z., Eden, H. S., Shen, B., Chen, X. 2012; 7 (4): 363-372


    The purpose of this study was to synthesize, characterize and tailor the surface properties of magnetic nanoparticles with biocompatible copolymer coatings and to evaluate the efficiency of the resulting nanoconjugates as magnetic resonance imaging (MRI) contrast agents for liver imaging. Magnetic nanoparticles with core diameters of 10 and 30 nm were synthesized by pyrolysis and were subsequently coated with a copolymer containing either carboxyl (SHP) or methoxy groups as termini. All four formulas, and ferumoxides (Feridex I.V.(®)), were individually injected intravenously into separate, normal Balb/C mice (at 2.5, 1.0 and 0.56 mg Fe kg(-1)), and the animals underwent T(2)-weighted MRI at multiple time points post injection (p.i.) to evaluate the hepatic uptake and clearance. Furthermore, we compared the abilities of the new formulas and Feridex to detect tumors in an orthotropic Huh7 tumor model. Transmission electron microscopy (TEM) revealed a narrow size distribution of both the 10 and 30 nm nanoparticles, in contrast to a wide size distribution of Feridex. MTT, apoptosis and cyclin/DNA flow cytometry assays showed that the polymer coated nanoparticles had no adverse effect on cell growth. Among all the tested formulas, including Feridex, SHP-30 showed the highest macrophage uptake at the in vitro level. In vivo MRI studies on normal mice confirmed the superiority of SHP-30 in inducing hypointensities in the liver tissue, especially at clinical dose (0.56 mg Fe kg(-1)) and 3 T field. SHP-30 showed better contrast-to-noise ratio than Feridex on the orthotropic Huh7 tumor model. SHP-30 was found to be an efficient contrast agent for liver MR imaging. The success of this study suggests that, by improving the synthetic approach and by tuning the surface properties of IONPs, one can arrive at better formulas than Feridex for clinical practice.

    View details for DOI 10.1002/cmmi.494

    View details for Web of Science ID 000304665100002

    View details for PubMedID 22649042

  • Lu-177-DO3A-HSA-Z(EGFR:1907): characterization as a potential radiopharmaceutical for radionuclide therapy of EGFR-expressing head and neck carcinomas JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY Hoppmann, S., Qi, S., Miao, Z., Liu, H., Jiang, H., Cutler, C. S., Bao, A., Cheng, Z. 2012; 17 (5): 709-718


    Epidermal growth factor receptor 1 (EGFR) is an attractive target for radionuclide therapy of head and neck carcinomas. Affibody molecules against EGFR (Z(EGFR)) show excellent tumor localizations in imaging studies. However, one major drawback is that radiometal-labeled Affibody molecules display extremely high uptakes in the radiosensitive kidneys which may impact their use as radiotherapeutic agents. The purpose of this study is to further explore whether radiometal-labeled human serum albumin (HSA)-Z(EFGR) bioconjugates display desirable profiles for the use in radionuclide therapy of EGFR-positive head and neck carcinomas. The Z(EFGR) analog, Ac-Cys-Z(EGFR:1907), was site-specifically conjugated with HSA. The resulting bioconjugate 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A)-HSA-Z(EGFR:1907) was then radiolabeled with either (64)Cu or (177)Lu and subjected to in vitro cell uptake and internalization studies using the human oral squamous carcinoma cell line SAS. Positron emission tomography (PET), single photon emission computed tomography (SPECT), and biodistribution studies were conducted using SAS-tumor-bearing mice. Cell studies revealed a high (8.43 ± 0.55 % at 4 h) and specific (0.95 ± 0.09 % at 4 h) uptake of (177)Lu-DO3A-HSA-Z(EGFR:1907) as determined by blocking with nonradioactive Z(EGFR:1907). The internalization of (177)Lu-DO3A-HSA-Z(EGFR:1907) was verified in vitro and found to be significantly higher than that of (177)Lu-labeled Z(EFGR) at 2-24 h of incubation. PET and SPECT studies showed good tumor imaging contrasts. The biodistribution of (177)Lu-DO3A-HSA-Z(EGFR:1907) in SAS-tumor-bearing mice displayed high tumor uptake (5.1 ± 0.44 % ID/g) and liver uptake (31.5 ± 7.66 % ID/g) and moderate kidney uptake (8.5 ± 1.08 % ID/g) at 72 h after injection. (177)Lu-DO3A-HSA-Z(EGFR:1907) shows promising in vivo profiles and may be a potential radiopharmaceutical for radionuclide therapy of EGFR-expressing head and neck carcinomas.

    View details for DOI 10.1007/s00775-012-0890-3

    View details for Web of Science ID 000304566400004

    View details for PubMedID 22418921

  • A Four-Arm Star-Shaped Poly(ethylene glycol) (StarPEG) Platform for Bombesin Peptide Delivery to Gastrin-Releasing Peptide Receptors in Prostate Cancer ACS MACRO LETTERS Xu, Y., Huang, W., Ren, G., Qi, S., Jiang, H., Miao, Z., Liu, H., Lucente, E., Bu, L., Shen, B., Barron, A., Cheng, Z. 2012; 1 (6): 753-757

    View details for DOI 10.1021/mz300105n

    View details for Web of Science ID 000305320600023

  • Evaluation of Four Affibody-Based Near-Infrared Fluorescent Probes for Optical Imaging of Epidermal Growth Factor Receptor Positive Tumors BIOCONJUGATE CHEMISTRY Qi, S., Miao, Z., Liu, H., Xu, Y., Feng, Y., Cheng, Z. 2012; 23 (6): 1149-1156

    View details for DOI 10.1021/bc200596a

    View details for Web of Science ID 000305358700007

  • Endoscopic imaging of Cerenkov luminescence BIOMEDICAL OPTICS EXPRESS Kothapalli, S., Liu, H., Liao, J. C., Cheng, Z., Gambhir, S. S. 2012; 3 (6): 1215-1225


    We demonstrate feasibility of endoscopic imaging of Cerenkov light originated when charged nuclear particles, emitted from radionuclides, travel through a biological tissue of living subjects at superluminal velocity. The endoscopy imaging system consists of conventional optical fiber bundle/ clinical endoscopes, an optical imaging lens system, and a sensitive low-noise charge coupled device (CCD) camera. Our systematic studies using phantom samples show that Cerenkov light from as low as 1 µCi of radioactivity emitted from (18)F-Fluorodeoxyglucose (FDG) can be coupled and transmitted through conventional optical fibers and endoscopes. In vivo imaging experiments with tumor bearing mice, intravenously administered with (18)F-FDG, further demonstrated that Cerenkov luminescence endoscopy is a promising new tool in the field of endoscopic molecular imaging.

    View details for Web of Science ID 000304965700007

    View details for PubMedID 22741069

    View details for PubMedCentralID PMC3370963

  • Radioluminescent nanophosphors enable multiplexed small-animal imaging OPTICS EXPRESS Carpenter, C. M., Sun, C., Pratx, G., Liu, H., Cheng, Z., Xing, L. 2012; 20 (11): 11598-11604


    We demonstrate the ability to image multiple nanoparticle-based contrast agents simultaneously using a nanophosphor platform excited by either radiopharmaceutical or X-ray irradiation. These radioluminescent nanoparticles emit optical light at unique wavelengths depending on their lanthanide dopant, enabling multiplexed imaging. This study demonstrates the separation of two distinct nanophosphor contrast agents in gelatin phantoms with a recovered phosphor separation correlation of -0.98. The ability to distinguish the two nanophosphors and a Cerenkov component is then demonstrated in a small animal phantom. Combined with the high-resolution potential of low-scattering X-ray excitation, this imaging technique may be a promising method to probe molecular processes in living organisms.

    View details for Web of Science ID 000304403100002

    View details for PubMedID 22714145

  • In Vivo Biodistribution and Small Animal PET of Cu-64-Labeled Antimicrobial Peptoids BIOCONJUGATE CHEMISTRY Seo, J., Ren, G., Liu, H., Miao, Z., Park, M., Wang, Y., Miller, T. M., Barron, A. E., Cheng, Z. 2012; 23 (5): 1069-1079

    View details for DOI 10.1021/bc300091d

    View details for Web of Science ID 000304027500020

  • Human Serum Albumin Conjugated Biomolecules for Cancer Molecular Imaging CURRENT PHARMACEUTICAL DESIGN Yang, M., Hoppmann, S., Chen, L., Cheng, Z. 2012; 18 (8): 1023-1031


    Molecular imaging is a fast growing field in biomedical research. The discovery, development and continual improvement of molecular probes are important for ongoing research efforts in molecular imaging. Human serum albumin (HSA) offers favorable characteristics and opportunities as a platform protein for molecular imaging probe discovery and optimization. It has many advantages, including alternation of biodistribution and pharmacokinetic properties of molecular imaging probes, enhancing the blood half-life of bio-molecules, and making these molecules multivalent, all of which make HSA a promising carrier for cancer-targeted imaging and therapy. Numerous studies have focused on the development and application of HSA-based cancer imaging and treatment. This review gives a brief account of albumin-based molecular probes, focusing on their applications in cancer molecular imaging, such as PET/SPECT, MRI and optical imaging.

    View details for Web of Science ID 000304445900002

    View details for PubMedID 22272822

  • Optical Imaging with Her2-Targeted Affibody Molecules Can Monitor Hsp90 Treatment Response in a Breast Cancer Xenograft Mouse Model CLINICAL CANCER RESEARCH van de Ven, S. M., Elias, S. G., Chan, C. T., Miao, Z., Cheng, Z., De, A., Gambhir, S. S. 2012; 18 (4): 1073-1081


    To determine whether optical imaging can be used for in vivo therapy response monitoring as an alternative to radionuclide techniques. For this, we evaluated the known Her2 response to 17-dimethylaminoethylamino-17-demethoxygeldanamycin hydrochloride (17-DMAG) treatment, an Hsp90 inhibitor.After in vitro 17-DMAG treatment response evaluation of MCF7 parental cells and 2 HER2-transfected clones (clone A medium, B high Her2 expression), we established human breast cancer xenografts in nude mice (only parental and clone B) for in vivo evaluation. Mice received 120 mg/kg of 17-DMAG in 4 doses at 12-hour intervals intraperitonially (n = 14) or PBS as carrier control (n = 9). Optical images were obtained both pretreatment (day 0) and posttreatment (day 3, 6, and 9), always 5 hours postinjection of 500 pmol of anti-Her2 Affibody-AlexaFluor680 via tail vein (with preinjection background subtraction). Days 3 and 9 in vivo optical imaging signal was further correlated with ex vivo Her2 levels by Western blot after sacrifice.Her2 expression decreased with 17-DMAG dose in vitro. In vivo optical imaging signal was reduced by 22.5% in clone B (P = 0.003) and by 9% in MCF7 parental tumors (P = 0.23) 3 days after 17-DMAG treatment; optical imaging signal recovered in both tumor types at days 6 to 9. In the carrier group, no signal reduction was observed. Pearson correlation of in vivo optical imaging signal with ex vivo Her2 levels ranged from 0.73 to 0.89.Optical imaging with an affibody can be used to noninvasively monitor changes in Her2 expression in vivo as a response to treatment with an Hsp90 inhibitor, with results similar to response measurements in positron emission tomography imaging studies.

    View details for DOI 10.1158/1078-0432.CCR-10-3213

    View details for Web of Science ID 000300628100017

    View details for PubMedID 22235098

    View details for PubMedCentralID PMC3288571

  • Proof-of-Concept Study of Monitoring Cancer Drug Therapy with Cerenkov Luminescence Imaging JOURNAL OF NUCLEAR MEDICINE Xu, Y., Chang, E., Liu, H., Jiang, H., Gambhir, S. S., Cheng, Z. 2012; 53 (2): 312-317


    Cerenkov luminescence imaging (CLI) has emerged as a less expensive, easier-to-use, and higher-throughput alternative to other nuclear imaging modalities such as PET. It is expected that CLI will find many applications in biomedical research such as cancer detection, probe development, drug screening, and therapy monitoring. In this study, we explored the possibility of using CLI to monitor drug efficacy by comparisons against PET. To assess the performance of both modalities in therapy monitoring, 2 murine tumor models (large cell lung cancer cell line H460 and prostate cancer cell line PC3) were given bevacizumab versus vehicle treatments. Two common radiotracers, 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) and (18)F-FDG, were used to monitor bevacizumab treatment efficacy.One group of mice (n = 6) was implanted with H460 xenografts bilaterally in the shoulder region, divided into treatment and control groups (n = 3 each), injected with (18)F-FLT, and imaged with PET immediately followed by CLI. The other group of mice (n = 6) was implanted with PC3 xenografts in the same locations, divided into treatment and control groups (n = 3 each), injected with (18)F-FDG, and imaged by the same modalities. Bevacizumab treatment was performed by 2 injections of 20 mg/kg at days 0 and 2.On (18)F-FLT scans, both CLI and PET revealed significantly decreased signals from H460 xenografts in treated mice from pretreatment to day 3. Moderately increased to unchanged signals were observed in untreated mice. On (18)F-FDG scans, both CLI and PET showed relatively unchanged signals from PC3 tumors in both treated and control groups. Quantifications of tumor signals of Cerenkov luminescence and PET images showed that the 2 modalities had excellent correlations (R(2) > 0.88 across all study groups).CLI and PET exhibit excellent correlations across different tumor xenografts and radiotracers. This is the first study, to our knowledge, demonstrating the use of CLI for monitoring cancer treatment. The findings warrant further exploration and optimization of CLI as an alternative to PET in preclinical therapeutic monitoring and drug screening.

    View details for DOI 10.2967/jnumed.111.094623

    View details for Web of Science ID 000300032800024

    View details for PubMedID 22241909

  • Evaluation of Four Affibody-Based Near-Infrared Fluorescent Probes for Optical Imaging of Epidermal Growth Factor Receptor Positive Tumors. Bioconjugate chemistry Qi, S. n., Miao, Z. n., Liu, H. n., Xu, Y. n., Feng, Y. n., Cheng, Z. n. 2012


    The epidermal growth factor receptor 1 (EGFR) has become an attractive target for cancer molecular imaging and therapy. An Affibody protein with strong binding affinity for EGFR, Z(EGFR:1907), has been reported. We are interested in translating Affibody molecules to potential clinical optical imaging of EGFR positive cancers. In this study, four anti-EGFR Affibody based near-infrared (NIR) fluorescent probes were thus prepared, and their in vivo performance was evaluated in the mice bearing EGFR positive subcutaneous A431 tumors. Methods: The Affibody analogue, Ac-Cys-Z(EGFR:1907), was synthesized using solid-phase peptide synthesis method. The purified small protein was then site-specifically conjugated with four NIR fluorescent dyes, Cy5.5-monomaleimide, Alex-Fluor-680-maleimide, SRfluor680-maleimide, or IRDye-800CW-maleimide, to produce four optical probes-Cy5.5-Z(EGFR:1907), Alexa680-Z(EGFR:1907), SR680-Z(EGFR:1907), and 800CW-Z(EGFR:1907). The EGFR binding property and specificity of the four NIR fluorescent Affibody probes were studied by fluorescence microscopy using high EGFR expressing A431 cells and low expressing MCF7 cells. The binding affinities of the probes (K(D)) to EGFR were further determined by flow cytometry. In vivo optical imaging of the four probes was performed in the mice bearing subcutaneous A431 tumors. Results: The four NIR optical probes were prepared in high purity. In vitro cell imaging studies demonstrated that all of them could specifically bind to EGFR positive A431 cells while showing minimum uptake in low EGFR expressing MCF7 cells. Flow cytometry showed that Cy5.5-Z(EGFR:1907) and Alexa680-Z(EGFR:1907) possessed high binding affinity in low nanomolar range (43.6 ± 8.4 and 28.3 ± 4.9, respectively). In vivo optical imaging of the four probes revealed that they all showed fast tumor targeting ability and good tumor-to-normal tissue contrast as early as 0.5 h postinjection (p.i.). The tumor-to-normal tissue ratio reached a peak at 2 to 4 h p.i. by regional of interest (ROI) analysis of images. Ex vivo studies further demonstrated that the four probes had high tumor uptakes. Particularly, Cy5.5-Z(EGFR:1907) and Alex680-Z(EGFR:1907) displayed higher tumor-to-normal tissue ratios than those of the other two probes. Conclusion: This work demonstrates that Affibody proteins can be modified with different NIR fluorescent dyes and used for imaging of EGFR expressing tumors. Different NIR fluorescent dyes have variable impact on the in vitro binding and in vivo performance of the resulting Affibody based probes. Therefore, selection of an appropriate NIRF label is important for optical probe development. The probes developed are promising for further tumor imaging applications and clinical translation. Particularly, Alex680-Z(EGFR:1907) and Cy5.5-Z(EGFR:1907) are excellent candidates as EGFR-targeted probes for optical imaging.

    View details for PubMedID 22621238

  • In Vitro and In Vivo Uncaging and Bioluminescence Imaging by Using Photocaged Upconversion Nanoparticles ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Yang, Y., Shao, Q., Deng, R., Wang, C., Teng, X., Cheng, K., Cheng, Z., Huang, L., Liu, Z., Liu, X., Xing, B. 2012; 51 (13): 3125-3129

    View details for DOI 10.1002/anie.201107919

    View details for Web of Science ID 000301792000008

    View details for PubMedID 22241651

  • In-111-Labeled Cystine-Knot Peptides Based on the Agouti-Related Protein for Targeting Tumor Angiogenesis JOURNAL OF BIOMEDICINE AND BIOTECHNOLOGY Jiang, L., Miao, Z., Kimura, R. H., Silverman, A. P., Ren, G., Liu, H., Lu, H., Cochran, J. R., Cheng, Z. 2012


    Agouti-related protein (AgRP) is a 4-kDa cystine-knot peptide of human origin with four disulfide bonds and four solvent-exposed loops. The cell adhesion receptor integrin α(v)β(3) is an important tumor angiogenesis factor that determines the invasiveness and metastatic ability of many malignant tumors. AgRP mutants have been engineered to bind to integrin α(v)β(3) with high affinity and specificity using directed evolution. Here, AgRP mutants 7C and 6E were radiolabeled with (111)In and evaluated for in vivo targeting of tumor integrin α(v)β(3) receptors. AgRP peptides were conjugated to the metal chelator 1, 4, 7, 10-tetra-azacyclododecane- N, N', N″, N'''-tetraacetic acid (DOTA) and radiolabeled with (111)In. The stability of the radiopeptides (111)In-DOTA-AgRP-7C and (111)In-DOTA-AgRP-6E was tested in phosphate-buffered saline (PBS) and mouse serum, respectively. Cell uptake assays of the radiolabeled peptides were performed in U87MG cell lines. Biodistribution studies were performed to evaluate the in vivo performance of the two resulting probes using mice bearing integrin-expressing U87MG xenograft tumors. Both AgRP peptides were easily labeled with (111)In in high yield and radiochemical purity (>99%). The two probes exhibited high stability in phosphate-buffered saline and mouse serum. Compared with (111)In-DOTA-AgRP-6E, (111)In-DOTA-AgRP-7C showed increased U87MG tumor uptake and longer tumor retention (5.74 ± 1.60 and 1.29 ± 0.02%ID/g at 0.5 and 24 h, resp.), which was consistent with measurements of cell uptake. Moreover, the tumor uptake of (111)In-DOTA-AgRP-7C was specifically inhibited by coinjection with an excess of the integrin-binding peptidomimetic c(RGDyK). Thus, (111)In-DOTA-AgRP-7C is a promising probe for targeting integrin α(v)β(3) positive tumors in living subjects.

    View details for DOI 10.1155/2012/368075

    View details for Web of Science ID 000303728900001

    View details for PubMedID 22570527

    View details for PubMedCentralID PMC3336217

  • Cerenkov Luminescence Imaging (CLI) for cancer therapy monitoring. Journal of visualized experiments : JoVE Xu, Y., Liu, H., Chang, E., Jiang, H., Cheng, Z. 2012: e4341-?


    In molecular imaging, positron emission tomography (PET) and optical imaging (OI) are two of the most important and thus most widely used modalities. PET is characterized by its excellent sensitivity and quantification ability while OI is notable for non-radiation, relative low cost, short scanning time, high throughput, and wide availability to basic researchers. However, both modalities have their shortcomings as well. PET suffers from poor spatial resolution and high cost, while OI is mostly limited to preclinical applications because of its limited tissue penetration along with prominent scattering optical signals through the thickness of living tissues. Recently a bridge between PET and OI has emerged with the discovery of Cerenkov Luminescence Imaging (CLI). CLI is a new imaging modality that harnesses Cerenkov Radiation (CR) to image radionuclides with OI instruments. Russian Nobel laureate Alekseyevich Cerenkov and his colleagues originally discovered CR in 1934. It is a form of electromagnetic radiation emitted when a charged particle travels at a superluminal speed in a dielectric medium. The charged particle, whether positron or electron, perturbs the electromagnetic field of the medium by displacing the electrons in its atoms. After passing of the disruption photons are emitted as the displaced electrons return to the ground state. For instance, one (18)F decay was estimated to produce an average of 3 photons in water. Since its emergence, CLI has been investigated for its use in a variety of preclinical applications including in vivo tumor imaging, reporter gene imaging, radiotracer development, multimodality imaging, among others. The most important reason why CLI has enjoyed much success so far is that this new technology takes advantage of the low cost and wide availability of OI to image radionuclides, which used to be imaged only by more expensive and less available nuclear imaging modalities such as PET. Here, we present the method of using CLI to monitor cancer drug therapy. Our group has recently investigated this new application and validated its feasibility by a proof-of-concept study. We demonstrated that CLI and PET exhibited excellent correlations across different tumor xenografts and imaging probes. This is consistent with the overarching principle of CR that CLI essentially visualizes the same radionuclides as PET. We selected Bevacizumab (Avastin; Genentech/Roche) as our therapeutic agent because it is a well-known angiogenesis inhibitor. Maturation of this technology in the near future can be envisioned to have a significant impact on preclinical drug development, screening, as well as therapy monitoring of patients receiving treatments.

    View details for DOI 10.3791/4341

    View details for PubMedID 23183774

  • In Vivo Biodistribution and Small Animal PET of (64)Cu-Labeled Antimicrobial Peptoids. Bioconjugate chemistry Seo, J. n., Ren, G. n., Liu, H. n., Miao, Z. n., Park, M. n., Wang, Y. n., Miller, T. M., Barron, A. E., Cheng, Z. n. 2012


    Peptoids are a rapidly developing class of biomimetic polymers based on oligo-N-substituted glycine backbones, designed to mimic peptides and proteins. Inspired by natural antimicrobial peptides, a group of cationic amphipathic peptoids has been successfully discovered with potent, broad-spectrum activity against pathogenic bacteria; however, there are limited studies to address the in vivo pharmacokinetics of the peptoids. Herein, (64)Cu-labeled DOTA conjugates of three different peptoids and two control peptides were synthesized and assayed in vivo by both biodistribution studies and small animal positron emission tomography (PET). The study was designed in a way to assess how structural differences of the peptidomimetics affect in vivo pharmacokinetics. As amphipathic molecules, major uptake of the peptoids occurred in the liver. Increased kidney uptake was observed by deleting one hydrophobic residue in the peptoid, and (64)Cu-3 achieved the highest kidney uptake of all the conjugates tested in this study. In comparison to peptides, our data indicated that peptoids had general in vivo properties of higher tissue accumulation, slower elimination, and higher in vivo stability. Different administration routes (intravenous, intraperitoneal, and oral) were investigated with peptoids. When administered orally, the peptoids showed poor bioavailability, reminiscent of that of peptide. However, remarkably longer passage through the gastrointestinal (GI) tract without rapid digestion was observed for peptoids. These unique in vivo properties of peptoids were rationalized by efficient cellular membrane permeability and protease resistance of peptoids. The results observed in the biodistribution studies could be confirmed by PET imaging, which provides a reliable way to evaluate in vivo pharmacokinetic properties of peptoids noninvasively and in real time. The pharmacokinetic data presented here can provide insight for further development of the antimicrobial peptoids as pharmaceuticals.

    View details for PubMedID 22486390

    View details for PubMedCentralID PMC3410980

  • A Novel Clinically Translatable Fluorescent Nanoparticle for Targeted Molecular Imaging of Tumors in Living Subjects NANO LETTERS Gao, J., Chen, K., Luong, R., Bouley, D. M., Mao, H., Qiao, T., Gambhir, S. S., Cheng, Z. 2012; 12 (1): 281-286


    The use of quantum dots (QDs) in biomedical research has grown tremendously, yet successful examples of clinical applications are absent due to many clinical concerns. Here, we report on a new type of stable and biocompatible dendron-coated InP/ZnS core/shell QD as a clinically translatable nanoprobe for molecular imaging applications. The QDs (QD710-Dendron) were demonstrated to hold several significant features: near-infrared (NIR) emission, high stability in biological media, suitable size with possible renal clearance, and ability of extravasation. More importantly, a pilot mouse toxicity study confirmed that QD710-Dendron lacks significant toxicity at the doses tested. The acute tumor uptake of QD710-Dendron resulted in good contrast from the surrounding nontumorous tissues, indicating the possibility of passive targeting of the QDs. The highly specific targeting of QD710-Dendron-RGD(2) to integrin α(v)β(3)-positive tumor cells resulted in high tumor uptake and long retention of the nanoprobe at tumor sites. In summary, QD710-Dendron and RGD-modified nanoparticles demonstrate small size, high stability, biocompatibility, favorable in vivo pharmacokinetics, and successful tumor imaging properties. These features satisfy the requirements for clinical translation and should promote efforts to further investigate the possibility of using QD710-Dendron-based nanoprobes in the clinical setting in the near future.

    View details for DOI 10.1021/nl203526f

    View details for Web of Science ID 000298943100049

    View details for PubMedID 22172022

    View details for PubMedCentralID PMC3256290

  • Radioluminescent Nanophosphors Enable Multiplexed Small-Animal Imaging Optic Express Carpenter CM, Sun C, Pratx G, Liu H, Cheng Z, Xing L 2012; 20 (11): 11598-11604
  • A photonic crystal cavity-optical fiber tip nanoparticle sensor for biomedical applications Applied Physics Letters Shambat G, Kothapalli SR, Khurana A, Provine J, Sarmiento T, Cheng K, Cheng Z, Harris J, Daldrup-Link H, Gambhir SS, Vuckovi J. 2012; 100: 213702
  • Analysis of in situ and ex vivo alpha(V)beta(3) integrin expression during experimental carotid atherogenesis INTERNATIONAL JOURNAL OF NANOMEDICINE Yao, Y., Jiang, Y., Sheng, Z., Zhang, Y., An, Y., Yan, F., Ma, G., Liu, N., Teng, G., Cheng, Z. 2012; 7: 641-649


    Mural inflammation has been shown to contribute to the development of plaque, with the α(V)β(3) integrin highly expressed in atherosclerotic plaques. We herein examined α(V)β(3) integrin expression as a function of carotid atherosclerosis formation in the apolipoprotein E-deficient (apoE(-/-)) mouse.Constrictive collars were placed around the left common carotid arteries of apo E(-/-) mice maintained on a high-fat diet (n = 14). Before and 21 days following collar placement, in vivo serial magnetic resonance imaging (MRI) measurements of the carotid aortic diameter were performed using a 7T magnetic resonance (MR) scanner. Near- infrared fluorescence (NIRF) imaging was performed (n = 6) using an in vivo imaging system 0-24 hours following administration of 1.0 nmol c(RGDyK)-Cy5.5 via the tail vein. A competition experiment was performed by the co-injection of a saturating dose of bicyclic RGD peptide H-Glu[cyclo(Arg-Gly-Asp-D-Tyr-Lys)]2 (n = 3). Following image acquisition and sacrifice at 24 hours after injection, carotid arteries were harvested for histological analyses. Neointima formation and arterial remodeling in the carotid arteries of apoE(-/-) mice were induced by the placement of a constrictive collar. Significantly greater fluorescent signals were obtained from constrictive collar left common carotid arteries as compared to uninvolved aortic segments in constrictive collar mice. Binding to stenotic lesions was efficiently blocked in competition experiments. Immunostaining confirmed the presence of mural α(V)β(3) integrin expression in macrophages in the neointima. Signal intensity increased in a macrophage density-dependent fashion in the stenotic segments.Mural α(V)β(3) integrin expression, as determined using RGD-Cy5.5 near-infrared optical imaging, was increased in carotid arteries with constrictive collars in experimental mice. This expression can estimate the macrophage-bound inflammatory activity of atherosclerotic lesions.

    View details for DOI 10.2147/IJN.S28065

    View details for Web of Science ID 000302713100001

    View details for PubMedID 22334786

    View details for PubMedCentralID PMC3278228

  • Harnessing the Power of Radionuclides for Optical Imaging: Cerenkov Luminescence Imaging JOURNAL OF NUCLEAR MEDICINE Xu, Y., Liu, H., Cheng, Z. 2011; 52 (12): 2009-2018


    Over the past several years, nuclear imaging modalities such as PET and SPECT have received much attention because they have been instrumental not only in preclinical cancer research but also in nuclear medicine. Yet nuclear imaging is limited by high instrumentation cost and subsequently low availability to basic researchers. Cerenkov radiation, a relativistic physical phenomenon that was discovered 70 years ago, has recently become an intriguing subject of study in molecular imaging because of its potential in augmenting nuclear imaging, particularly in preclinical small-animal studies. The intrinsic capability of radionuclides emitting luminescent light from decay is promising because of the possibility of bridging nuclear imaging with optical imaging-a modality that is much less expensive, is easier to use, and has higher throughput than its nuclear counterpart. Thus, with the maturation of this novel imaging technology using Cerenkov radiation, which is termed Cerenkov luminescence imaging, it is foreseeable that advances in both nuclear imaging and preclinical research involving radioisotopes will be significantly accelerated in the near future.

    View details for DOI 10.2967/jnumed.111.092965

    View details for Web of Science ID 000298162500039

    View details for PubMedID 22080446

  • Non-Invasive Imaging of Cysteine Cathepsin Activity in Solid Tumors Using a Cu-64-Labeled Activity-Based Probe PLOS ONE Ren, G., Blum, G., Verdoes, M., Liu, H., Syed, S., Edgington, L. E., Gheysens, O., Miao, Z., Jiang, H., Gambhir, S. S., Bogyo, M., Cheng, Z. 2011; 6 (11)


    The papain family of cysteine cathepsins are actively involved in multiple stages of tumorigenesis. Because elevated cathepsin activity can be found in many types of human cancers, they are promising biomarkers that can be used to target radiological contrast agents for tumor detection. However, currently there are no radiological imaging agents available for these important molecular targets. We report here the development of positron emission tomography (PET) radionuclide-labeled probes that target the cysteine cathepsins by formation of an enzyme activity-dependent bond with the active site cysteine. These probes contain an acyloxymethyl ketone (AOMK) functional group that irreversibly labels the active site cysteine of papain family proteases attached to a 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) tag for labeling with (64)Cu for PET imaging studies. We performed biodistribution and microPET imaging studies in nude mice bearing subcutaneous tumors expressing various levels of cysteine cathepsin activity and found that the extent of probe uptake by tumors correlated with overall protease activity as measured by biochemical methods. Furthermore, probe signals could be reduced by pre-treatment with a general cathepsin inhibitor. We also found that inclusion of a Cy5 tag on the probe increased tumor uptake relative to probes lacking this fluorogenic dye. Overall, these results demonstrate that small molecule activity-based probes carrying radio-tracers can be used to image protease activity in living subjects.

    View details for DOI 10.1371/journal.pone.0028029

    View details for Web of Science ID 000297789900039

    View details for PubMedID 22132198

    View details for PubMedCentralID PMC3221694

  • A novel F-18-labeled two-helix scaffold protein for PET imaging of HER2-positive tumor EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING Miao, Z., Ren, G., Jiang, L., Liu, H., Webster, J. M., Zhang, R., Namavari, M., Gambhir, S. S., Syud, F., Cheng, Z. 2011; 38 (11): 1977-1984


    Two-helix scaffold proteins (~ 5 kDa) against human epidermal growth factor receptor type 2 (HER2) have been discovered in our previous work. In this research we aimed to develop an (18)F-labeled two-helix scaffold protein for positron emission tomography (PET) imaging of HER2-positive tumors.An aminooxy-functionalized two-helix peptide (AO-MUT-DS) with high HER2 binding affinity was synthesized through conventional solid phase peptide synthesis. The purified linear peptide was cyclized by I(2) oxidation to form a disulfide bridge. The cyclic peptide was then conjugated with a radiofluorination synthon, 4-(18)F-fluorobenzyl aldehyde ((18)F-FBA), through the aminooxy functional group at the peptide N terminus (30% yield, non-decay corrected). The binding affinities of the peptides were analyzed by Biacore analysis. Cell uptake assay of the resulting PET probe, (18)F-FBO-MUT-DS, was performed at 37°C. (18)F-FBO-MUT-DS with high specific activity (20-32 MBq/nmol, 88-140 μCi/μg, end of synthesis) was injected into mice xenograft model bearing SKOV3 tumor. MicroPET and biodistribution and metabolic stability studies were then conducted.Cell uptake assays showed high and specific cell uptake (~12% applied activity at 1 h) by incubation of (18)F-FBO-MUT-DS with HER2 high-expressing SKOV3 ovarian cancer cells. The affinities (K(D)) of AO-MUT-DS and FBO-MUT-DS as tested by Biacore analysis were 2 and 1 nM, respectively. In vivo small animal PET demonstrated fast tumor targeting, high tumor accumulation, and good tumor to normal tissue contrast of (18)F-FBO-MUT-DS. Biodistribution studies further revealed that the probe had excellent tumor uptake (6.9%ID/g at 1 h post-injection) and was cleared through both liver and kidneys. Co-injection of the probe with 500 μg of HER2 Affibody protein reduced the tumor uptake (6.9 vs 1.8%ID/g, p < 0.05).F-FBO-MUT-DS displays excellent HER2 targeting ability and tumor PET imaging quality. The two-helix scaffold proteins are suitable for development of (18)F-based PET probes.

    View details for DOI 10.1007/s00259-011-1879-9

    View details for Web of Science ID 000295680200004

    View details for PubMedID 21761266

  • Protein scaffold-based molecular probes for cancer molecular imaging AMINO ACIDS Miao, Z., Levi, J., Cheng, Z. 2011; 41 (5): 1037-1047


    Protein scaffold molecules are powerful reagents for targeting various cell signal receptors, enzymes, cytokines and other cancer-related molecules. They belong to the peptide and small protein platform with distinct properties. For the purpose of development of new generation molecular probes, various protein scaffold molecules have been labeled with imaging moieties and evaluated both in vitro and in vivo. Among the evaluated probes Affibody molecules and analogs, cystine knot peptides, and nanobodies have shown especially good characteristics as protein scaffold platforms for development of in vivo molecular probes. Quantitative data obtained from positron emission tomography, single photon emission computed tomography/CT, and optical imaging together with biodistribution studies have shown high tumor uptakes and high tumor-to-blood ratios for these probes. High tumor contrast imaging has been obtained within 1 h after injection. The success of those molecular probes demonstrates the adequacy of protein scaffold strategy as a general approach in molecular probe development.

    View details for DOI 10.1007/s00726-010-0503-9

    View details for Web of Science ID 000296469100003

    View details for PubMedID 20174842

    View details for PubMedCentralID PMC2914822

  • One-step radiosynthesis of F-18-AlF-NOTA-RGD(2) for tumor angiogenesis PET imaging EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING Liu, S., Liu, H., Jiang, H., Xu, Y., Zhang, H., Cheng, Z. 2011; 38 (9): 1732-1741


    One of the major obstacles of the clinical translation of (18)F-labeled arginine-glycine-aspartic acid (RGD) peptides has been the laborious multistep radiosynthesis. In order to facilitate the application of RGD-based positron emission tomography (PET) probes in the clinical setting we investigated in this study the feasibility of using the chelation reaction between Al(18)F and a macrocyclic chelator-conjugated dimeric RGD peptide as a simple one-step (18)F labeling strategy for development of a PET probe for tumor angiogenesis imaging.Dimeric cyclic peptide E[c(RGDyK)](2) (RGD(2)) was first conjugated with a macrocyclic chelator, 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA), and the resulting bioconjugate NOTA-RGD(2) was then radiofluorinated via Al(18)F intermediate to synthesize (18)F-AlF-NOTA-RGD(2). Integrin binding affinities of the peptides were assessed by a U87MG cell-based receptor binding assay using (125)I-echistatin as the radioligand. The tumor targeting efficacy and in vivo profile of (18)F-AlF-NOTA-RGD(2) were further evaluated in a subcutaneous U87MG glioblastoma xenograft model by microPET and biodistribution.NOTA-RGD(2) was successfully (18)F-fluorinated with good yield within 40 min using the Al(18)F intermediate. The IC(50) of (19)F-AlF-NOTA-RGD(2) was determined to be 46 ± 4.4 nM. Quantitative microPET studies demonstrated that (18)F-AlF-NOTA-RGD(2) showed high tumor uptake, fast clearance from the body, and good tumor to normal organ ratios.NOTA-RGD(2) bioconjugate has been successfully prepared and labeled with Al(18)F in one single step of radiosynthesis. The favorable in vivo performance and the short radiosynthetic route of (18)F-AlF-NOTA-RGD(2) warrant further optimization of the probe and the radiofluorination strategy to accelerate the clinical translation of (18)F-labeled RGD peptides.

    View details for DOI 10.1007/s00259-011-1847-4

    View details for Web of Science ID 000293637900017

    View details for PubMedID 21617974

  • Adipose tissue-derived stem cells display a proangiogenic phenotype on 3D scaffolds JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A Neofytou, E. A., Chang, E., Patloia, B., Joubert, L., Rajadas, J., Gambhir, S. S., Cheng, Z., Robbins, R. C., Beygui, R. E. 2011; 98A (3): 383-393


    Ischemic heart disease is the leading cause of death worldwide. Recent studies suggest that adipose tissue-derived stem cells (ASCs) can be used as a potential source for cardiovascular tissue engineering due to their ability to differentiate along the cardiovascular lineage and to adopt a proangiogenic phenotype. To understand better ASCs' biology, we used a novel 3D culture device. ASCs' and b.END-3 endothelial cell proliferation, migration, and vessel morphogenesis were significantly enhanced compared to 2D culturing techniques. ASCs were isolated from inguinal fat pads of 6-week-old GFP+/BLI+ mice. Early passage ASCs cells (P3-P4), PKH26-labeled murine b.END-3 cells or a co-culture of ASCs and b.END-3 cells were seeded at a density of 1 × 10(5) on three different surface configurations: (a) a 2D surface of tissue culture plastic, (b) Matrigel, and (c) a highly porous 3D scaffold fabricated from inert polystyrene. VEGF expression, cell proliferation, and tubulization, were assessed using optical microscopy, fluorescence microscopy, 3D confocal microscopy, and SEM imaging (n = 6). Increased VEGF levels were seen in conditioned media harvested from co-cultures of ASCs and b.END-3 on either Matrigel or a 3D matrix. Fluorescence, confocal, SEM, bioluminescence revealed improved cell, proliferation, and tubule formation for cells seeded on the 3D polystyrene matrix. Collectively, these data demonstrate that co-culturing ASCs with endothelial cells in a 3D matrix environment enable us to generate prevascularized tissue-engineered constructs. This can potentially help us to surpass the tissue thickness limitations faced by the tissue engineering community today.

    View details for DOI 10.1002/jbm.a.33113

    View details for Web of Science ID 000293699800007

  • Preclinical Evaluation of Raman Nanoparticle Biodistribution for their Potential Use in Clinical Endoscopy Imaging SMALL Zavaleta, C. L., Hartman, K. B., Miao, Z., James, M. L., Kempen, P., Thakor, A. S., Nielsen, C. H., Sinclair, R., Cheng, Z., Gambhir, S. S. 2011; 7 (15): 2232-2240


    Raman imaging offers unsurpassed sensitivity and multiplexing capabilities. However, its limited depth of light penetration makes direct clinical translation challenging. Therefore, a more suitable way to harness its attributes in a clinical setting would be to couple Raman spectroscopy with endoscopy. The use of an accessory Raman endoscope in conjunction with topically administered tumor-targeting Raman nanoparticles during a routine colonoscopy could offer a new way to sensitively detect dysplastic lesions while circumventing Raman's limited depth of penetration and avoiding systemic toxicity. In this study, the natural biodistribution of gold surface-enhanced Raman scattering (SERS) nanoparticles is evaluated by radiolabeling them with (64) Cu and imaging their localization over time using micropositron emission tomography (PET). Mice are injected either intravenously (IV) or intrarectally (IR) with approximately 100 microcuries (μCi) (3.7 megabecquerel (MBq)) of (64) Cu-SERS nanoparticles and imaged with microPET at various time points post injection. Quantitative biodistribution data are obtained as % injected dose per gram (%ID g(-1)) from each organ, and the results correlate well with the corresponding microPET images, revealing that IV-injected mice have significantly higher uptake (p < 0.05) in the liver (5 h = 8.96% ID g(-1); 24 h = 8.27% ID g(-1)) than IR-injected mice (5 h = 0.09% ID g(-1); 24 h = 0.08% ID g(-1)). IR-injected mice show localized uptake in the large intestine (5 h = 10.37% ID g(-1); 24 h = 0.42% ID g(-1)) with minimal uptake in other organs. Raman imaging of excised tissues correlate well with biodistribution data. These results suggest that the topical application of SERS nanoparticles in the mouse colon appears to minimize their systemic distribution, thus avoiding potential toxicity and supporting the clinical translation of Raman spectroscopy as an endoscopic imaging tool.

    View details for DOI 10.1002/smll.201002317

    View details for Web of Science ID 000294361200015

    View details for PubMedID 21608124

  • Molecular Probes for Bioluminescence Imaging CURRENT ORGANIC SYNTHESIS Wu, S., Chang, E., Cheng, Z. 2011; 8 (4): 488-497
  • Recent Progress in Radiofluorination of Peptides for PET Molecular Imaging CURRENT ORGANIC SYNTHESIS Liu, S., Shen, B., Chin, F. T., Cheng, Z. 2011; 8 (4): 584-592
  • Synthesis and Radioluminescence of PEGylated Eu3+-doped Nanophosphors as Bioimaging Probes ADVANCED MATERIALS Sun, C., Pratx, G., Carpenter, C. M., Liu, H., Cheng, Z., Gambhir, S. S., Xing, L. 2011; 23 (24): H195-H199

    View details for DOI 10.1002/adma.201100919

    View details for Web of Science ID 000293046600018

    View details for PubMedID 21557339

    View details for PubMedCentralID PMC4145869

  • Enzyme-Responsive Multifunctional Magnetic Nanoparticles for Tumor Intracellular Drug Delivery and Imaging CHEMISTRY-AN ASIAN JOURNAL Yang, Y., Aw, J., Chen, K., Liu, F., Padmanabhan, P., Hou, Y., Cheng, Z., Xing, B. 2011; 6 (6): 1381-1389


    Enzyme-responsive, hybrid, magnetic silica nanoparticles have been employed for multifunctional applications in selective drug delivery and intracellular tumor imaging. In this study, doxorubicin (Dox)-conjugated, enzyme-cleavable peptide precursors were covalently tethered onto the surface of uniform silica-coated magnetic nanoparticles through click chemistry. This enzyme-responsive nanoparticle conjugate demonstrated highly efficient Dox release upon specific enzyme interactions in vitro. It also exhibits multiple functions in selective tumor intracellular drug delivery and imaging in the tumor cells with high cathepsin B expression, whereas it exhibited lower cytotoxicity towards other cells without enzyme expression.

    View details for DOI 10.1002/asia.201000905

    View details for Web of Science ID 000292097700015

    View details for PubMedID 21548100

  • Macrocyclic chelator assembled RGD multimers for tumor targeting BIOORGANIC & MEDICINAL CHEMISTRY LETTERS Zhang, X., Liu, H., Miao, Z., Kimura, R., Fan, F., Cheng, Z. 2011; 21 (11): 3423-3426


    Macrocyclic chelators have been extensively used for complexation of metal ions. A widely used chelator, DOTA, has been explored as a molecular platform to assemble multiple bioactive peptides in this paper. The multivalent DOTA-peptide bioconjugates demonstrate promising tumor targeting ability.

    View details for DOI 10.1016/j.bmcl.2011.03.110

    View details for Web of Science ID 000290708300049

    View details for PubMedID 21524578

    View details for PubMedCentralID PMC3098922

  • In vivo imaging of embryonic stem cell therapy EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING Jiang, H., Cheng, Z., Tian, M., Zhang, H. 2011; 38 (4): 774-784


    Embryonic stem cells (ESCs) have the most pluripotent potential of any stem cell. These cells, isolated from the inner cell mass of the blastocyst, are "pluripotent," meaning that they can give rise to all cell types within the developing embryo. As a result, ESCs have been regarded as a leading candidate source for novel regenerative medicine therapies and have been used to derive diverse cell populations, including myocardial and endothelial cells. However, before they can be safely applied clinically, it is important to understand the in vivo behavior of ESCs and their derivatives. In vivo analysis of ESC-derived cells remains critically important to define how these cells may function in novel regenerative medicine therapies. In this review, we describe several available imaging modalities for assessing cell engraftment and discuss their strengths and limitations. We also analyze the applications of these modalities in assessing the utility of ESCs in regenerative medicine therapies.

    View details for DOI 10.1007/s00259-010-1667-y

    View details for Web of Science ID 000288255500020

    View details for PubMedID 21107558

  • Preliminary evaluation of Lu-177-labeled knottin peptides for integrin receptor-targeted radionuclide therapy EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING Jiang, L., Miao, Z., Kimura, R. H., Liu, H., Cochran, J. R., Culter, C. S., Bao, A., Li, P., Cheng, Z. 2011; 38 (4): 613-622


    Cystine knot peptides (knottins) 2.5D and 2.5F were recently engineered to bind integrin receptors with high affinity and specificity. These receptors are overexpressed on the surface of a variety of malignant human tumor cells and tumor neovasculature. In this study, 2.5D and 2.5F were labeled with a therapeutic radionuclide, (177)Lu, and the resulting radiopeptides were then evaluated as potential radiotherapeutic agents in a murine model of human glioma xenografts.Knottins 2.5D and 2.5F were synthesized using solid phase peptide synthesis, folded in vitro, and site-specifically coupled with 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (DOTA) at their N terminus for (177)Lu radiolabeling. The stability of the radiopeptides (177)Lu-DOTA-2.5D and (177)Lu-DOTA-2.5F was tested in both phosphate-buffered saline (PBS) and mouse serum. Cell uptake assays of the radiolabeled peptides were performed in U87MG integrin-expressing human glioma cells. The biodistribution studies of both (177)Lu-DOTA-2.5D and (177)Lu-DOTA-2.5F were examined in U87MG tumor-bearing athymic nu/nu mice. Radiation absorbed doses for the major tissues of a human adult male were calculated based on the mouse biodistribution results.DOTA-2.5D and DOTA-2.5F were labeled with (177)Lu at over 55% efficiency. High radiochemical purity for both radiocomplexes (> 95%) could be achieved after high performance liquid chromatography (HPLC) purification. Both radiopeptides were stable in PBS and mouse serum. Compared to (177)Lu-DOTA-2.5D (0.39 and 0.26 %ID/g at 2 and 24 h, respectively), (177)Lu-DOTA-2.5F showed much higher tumor uptake (2.16 and 0.78 %ID/g at 2 and 24 h, respectively). It also displayed higher tumor to blood ratios than that of (177)Lu-DOTA-2.5D (31.8 vs 18.7 at 24 h and 52.6 vs 20.6 at 72 h). Calculation of radiodosimetry for (177)Lu-DOTA-2.5D and (177)Lu-DOTA-2.5F suggested that tumor and kidney were tissues with the highest radiation absorbed doses. Moreover, (177)Lu-DOTA-2.5F had a higher tumor to kidney radiation absorbed dose ratio than that of (177)Lu-DOTA-2.5D.Cystine knot peptides can be successfully radiolabeled with (177)Lu for potential therapeutic applications. Knottin 2.5F labeled with (177)Lu exhibits favorable distribution in murine U87MG xenograft model; thus, it is a promising agent for radionuclide therapy of integrin-positive tumors.

    View details for DOI 10.1007/s00259-010-1684-x

    View details for Web of Science ID 000288255500002

    View details for PubMedID 21153409

  • Reproducibility study of [F-18]FPP(RGD)(2) uptake in murine models of human tumor xenografts EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING Chang, E., Liu, S., Gowrishankar, G., Yaghoubi, S., Wedgeworth, J. P., Chin, F., Berndorff, D., Gekeler, V., Gambhir, S. S., Cheng, Z. 2011; 38 (4): 722-730


    An (18)F-labeled PEGylated arginine-glycine-aspartic acid (RGD) dimer {[(18)F]FPP(RGD)(2)} has been used to image tumor α(v)β(3) integrin levels in preclinical and clinical studies. Serial positron emission tomography (PET) studies may be useful for monitoring antiangiogenic therapy response or for drug screening; however, the reproducibility of serial scans has not been determined for this PET probe. The purpose of this study was to determine the reproducibility of the integrin α(v)β(3)-targeted PET probe, [(18)F]FPP(RGD)(2,) using small animal PET.Human HCT116 colon cancer xenografts were implanted into nude mice (n = 12) in the breast and scapular region and grown to mean diameters of 5-15 mm for approximately 2.5 weeks. A 3-min acquisition was performed on a small animal PET scanner approximately 1 h after administration of [(18)F]FPP(RGD)(2) (1.9-3.8 MBq, 50-100 μCi) via the tail vein. A second small animal PET scan was performed approximately 6 h later after reinjection of the probe to assess for reproducibility. Images were analyzed by drawing an ellipsoidal region of interest (ROI) around the tumor xenograft activity. Percentage injected dose per gram (%ID/g) values were calculated from the mean or maximum activity in the ROIs. Coefficients of variation and differences in %ID/g values between studies from the same day were calculated to determine the reproducibility.The coefficient of variation (mean±SD) for %ID(mean)/g and %ID(max)/g values between [(18)F]FPP(RGD)(2) small animal PET scans performed 6 h apart on the same day were 11.1 ± 7.6% and 10.4 ± 9.3%, respectively. The corresponding differences in %ID(mean)/g and %ID(max)/g values between scans were -0.025 ± 0.067 and -0.039 ± 0.426. Immunofluorescence studies revealed a direct relationship between extent of α(ν)β(3) integrin expression in tumors and tumor vasculature with level of tracer uptake. Mouse body weight, injected dose, and fasting state did not contribute to the variability of the scans; however, consistent scanning parameters were necessary to ensure accurate studies, in particular, noting tumor volume, as well as making uniform: the time of imaging after injection and the ROI size. Reanalysis of ROI placement displayed variability for %ID(mean)/g of 6.6 ± 3.9% and 0.28 ± 0.12% for %ID(max)/g.[(18)F]FPP(RGD)(2) small animal PET mouse tumor xenograft studies are reproducible with relatively low variability.

    View details for DOI 10.1007/s00259-010-1672-1

    View details for Web of Science ID 000288255500015

    View details for PubMedID 21125268

  • Affibody-Functionalized Gold-Silica Nanoparticles for Raman Molecular Imaging of the Epidermal Growth Factor Receptor SMALL Jokerst, J. V., Miao, Z., Zavaleta, C., Cheng, Z., Gambhir, S. S. 2011; 7 (5): 625-633


    The affibody functionalization of fluorescent surface-enhanced Raman scattering gold-silica nanoparticles as multimodal contrast agents for molecular imaging specific to epidermal growth factor receptor (EGFR) is reported. This nanoparticle bioconjugate reports EGFR-positive A431 tumors with a signal nearly 35-fold higher than EGFR-negative MDA-435S tumors. The low-level EGFR expression in adjacent healthy tissue is 7-fold lower than in the positive tumors. Validation via competitive inhibition reduces the signal by a factor of six, and independent measurement of EGFR via flow cytometry correlates at R(2) = 0.92.

    View details for DOI 10.1002/smll.201002291

    View details for Web of Science ID 000288081900013

    View details for PubMedID 21302357

    View details for PubMedCentralID PMC3386295

  • Affibody-based nanoprobes for HER2-expressing cell and tumor imaging BIOMATERIALS Gao, J., Chen, K., Miao, Z., Ren, G., Chen, X., Gambhir, S. S., Cheng, Z. 2011; 32 (8): 2141-2148


    This article reports the affibody-based nanoprobes specifically target and image human epidermal growth factor receptor type 2 (HER2)-expressing cells and tumors. The affibody molecules are a promising class of targeting ligands with simple, robust, and precise structure and high affinity. Using near-infrared (NIR) quantum dots (QDs) and iron oxide (IO) nanoparticles as two representative nanomaterials, we designed anti-HER2 affibody molecules with a N-terminus cysteine residue (Cysteine-Z(HER2:342)) and precisely conjugated with maleimide-functionalized nanoparticles to make nanoparticle-affibody conjugates. The in vitro and in vivo study showed the conjugates are highly specific to target and image HER2-expressing cells and tumors. This work indicated the nanoparticle-affibody conjugates may be excellent candidates as targeting probes for molecular imaging and diagnosis.

    View details for DOI 10.1016/j.biomaterials.2010.11.053

    View details for Web of Science ID 000287061400015

    View details for PubMedID 21147502

    View details for PubMedCentralID PMC3032351

  • Radio labeled Affibody-Albumin Bioconjugates for HER2-Positive Cancer Targeting BIOCONJUGATE CHEMISTRY Hoppmann, S., Miao, Z., Liu, S., Liu, H., Ren, G., Bao, A., Cheng, Z. 2011; 22 (3): 413-421


    Affibody molecules have received significant attention in the fields of molecular imaging and drug development. However, Affibody scaffolds display an extremely high renal uptake, especially when modified with chelators and then labeled with radiometals. This unfavorable property may impact their use as radiotherapeutic agents in general and as imaging probes for the detection of tumors adjacent to kidneys in particular. Herein, we present a simple and generalizable strategy for reducing the renal uptake of Affibody molecules while maintaining their tumor uptake. Human serum albumin (HSA) was consecutively modified by 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid mono-N-hydroxysuccinimide ester (DOTA-NHS ester) and the bifunctional cross-linker sulfosuccinimidyl 4-[N-maleimidomethyl]cyclohexane-1-carboxylate (Sulfo-SMCC). The HER2 Affibody analogue, Ac-Cys-Z(HER2:342), was covalently conjugated with HSA, and the resulting bioconjugate DOTA-HSA-Z(HER2:342) was further radiolabeled with ⁶⁴Cu and ¹¹¹In and evaluated in vitro and in vivo. Radiolabeled DOTA-HSA-Z(HER2:342) conjugates displayed a significant and specific cell uptake into SKOV3 cell cultures. Positron emission tomography (PET) investigations using ⁶⁴Cu-DOTA-HSA-Z(HER2:342) were performed in SKOV3 tumor-bearing nude mice. High tumor uptake values (>14% ID/g at 24 and 48 h) and high liver accumulations but low kidney accumulations were observed. Biodistribution studies and single-photon emission computed tomography (SPECT) investigations using ¹¹¹In-DOTA-HSA-Z(HER2:342) validated these results. At 24 h post injection, the biodistribution data revealed high tumor (16.26% ID/g) and liver (14.11% ID/g) uptake but relatively low kidney uptake (6.06% ID/g). Blocking studies with coinjected, nonlabeled Ac-Cys-Z(HER2:342) confirmed the in vivo specificity of HER2. Radiolabeled DOTA-HSA-Z(HER2:342) Affibody conjugates are promising SPECT and PET-type probes for the imaging of HER2 positive cancer. More importantly, DOTA-HSA-Z(HER2:342) is suitable for labeling with therapeutic radionuclides (e.g., ⁹⁰Y or ¹⁷⁷Lu) for treatment studies. The approach of using HSA to optimize the pharmacokinetics and biodistribution profile of Affibodies may be extended to the design of many other targeting molecules.

    View details for DOI 10.1021/bc100432h

    View details for Web of Science ID 000288401400013

    View details for PubMedID 21299201

    View details for PubMedCentralID PMC3059402

  • Functional Mutation of Multiple Solvent-Exposed Loops in the Ecballium elaterium Trypsin Inhibitor-II Cystine Knot Miniprotein PLOS ONE Kimura, R. H., Jones, D. S., Jiang, L., Miao, Z., Cheng, Z., Cochran, J. R. 2011; 6 (2)


    The Ecballium elaterium trypsin inhibitor (EETI-II), a 28-amino acid member of the knottin family of peptides, contains three interwoven disulfide bonds that form multiple solvent-exposed loops. Previously, the trypsin binding loop of EETI-II has been engineered to confer binding to several alternative molecular targets. Here, EETI-II was further explored as a molecular scaffold for polypeptide engineering by evaluating the ability to mutate two of its structurally adjacent loops.Yeast surface display was used to engineer an EETI-II mutant containing two separate integrin binding epitopes. The resulting knottin peptide was comprised of 38 amino acids, and contained 11- and 10-residue loops compared to wild-type EETI-II, which naturally contains 6- and 5-residue loops, respectively. This knottin peptide bound to α(v)β(3) and α(v)β(5) integrins with affinities in the low nanomolar range, but bound weakly to the related integrins α(5)β(1) and α(iib)β(3). In addition, the engineered knottin peptide inhibited tumor cell adhesion to vitronectin, an extracellular matrix protein that binds to α(v)β(3) and α(v)β(5) integrins. A (64)Cu radiolabeled version of this knottin peptide demonstrated moderate serum stability and excellent tumor-to-muscle and tumor-to-blood ratios by positron emission tomography imaging in human tumor xenograft models. Tumor uptake was ∼3-5% injected dose per gram (%ID/g) at one hour post injection, with rapid clearance of probe through the kidneys.We demonstrated that multiple loops of EETI-II can be mutated to bind with high affinity to tumor-associated integrin receptors. The resulting knottin peptide contained 21 (>50%) non-native amino acids within two mutated loops, indicating that extended loop lengths and sequence diversity were well tolerated within the EETI-II scaffold. A radiolabeled version of this knottin peptide showed promise for non-invasive imaging of integrin expression in living subjects. However, reduced serum and metabolic stability were observed compared to an engineered integrin-binding EETI-II knottin peptide containing only one mutated loop.

    View details for DOI 10.1371/journal.pone.0016112

    View details for Web of Science ID 000287482800005

    View details for PubMedID 21364742

    View details for PubMedCentralID PMC3041754

  • Ferritin Enhances SPIO Tracking of C6 Rat Glioma Cells by MRI MOLECULAR IMAGING AND BIOLOGY Wang, J., Xie, J., Zhou, X., Cheng, Z., Gu, N., Teng, G., Hu, Q., Zhu, F., Chang, S., Zhang, F., Lu, G., Chen, X. 2011; 13 (1): 87-93


    To investigate the effect of ferritin protein overexpression on superparamagnetic iron oxide (SPIO) particle labeling of C6 rat glioma cells, and track the labeled cells in vivo using magnetic resonance imaging (MRI).A plasmid of H-chain of murine ferritin gene was constructed and transfected into C6 cells. The parental and the transfected C6 cells labeled with SPIO were bilaterally inoculated subcutaneously into nude mice. The mice were imaged by multiple T2-weighted MR scans after C6 cell inoculation. The mice were killed 2 weeks later, and the concentration of iron in the tumor tissue was measured by inductively coupled plasma.The iron concentration in xenografts derived from SPIO-labeled C6 cells that were transfected with ferritin plasmid was significantly higher than that in xenografts from parental C6 cells that were labeled with SPIO but not transfected (p = 0.034, N = 5). Ferritin-transfected C6 cells showed an improved T(2) contrast in vivo compared with parental cells labeled with SPIO but not transfected.Coordinating ferritin with SPIO can lead to a longer MRI cellular tracking period.

    View details for DOI 10.1007/s11307-010-0338-5

    View details for Web of Science ID 000286395600012

    View details for PubMedID 20440566

    View details for PubMedCentralID PMC2966504

  • PET Imaging of Integrin Positive Tumors Using F-18 Labeled Knottin Peptides THERANOSTICS Liu, S., Liu, H., Ren, G., Kimura, R. H., Cochran, J. R., Cheng, Z. 2011; 1: 403-412


    Purpose: Cystine knot (knottin) peptides, engineered to bind with high affinity to integrin receptors, have shown promise as molecular imaging agents in living subjects. The aim of the current study was to evaluate tumor uptake and in vivo biodistribution of (18)F-labeled knottins in a U87MG glioblastoma model.Procedures: Engineered knottin mutants 2.5D and 2.5F were synthesized using solid phase peptide synthesis and were folded in vitro, followed by radiolabeling with 4-nitrophenyl 2-(18)F-fluoropropionate ((18)F-NFP). The resulting probes, (18)F-FP-2.5D and (18)F-FP-2.5F, were evaluated in nude mice bearing U87MG tumor xenografts using microPET and biodistribution studies.Results: MicroPET imaging studies with (18)F-FP-2.5D and (18)F-FP-2.5F demonstrated high tumor uptake in U87MG xenograft mouse models. The probes exhibited rapid clearance from the blood and kidneys, thus leading to excellent tumor-to-normal tissue contrast. Specificity studies confirmed that (18)F-FP-2.5D and (18)F-FP-2.5F had reduced tumor uptake when co-injected with a large excess of the peptidomimetic c(RGDyK) as a blocking agent.Conclusions: (18)F-FP-2.5D and (18)F-FP-2.5F showed reduced gallbladder uptake compared with previously published (18)F-FB-2.5D. (18)F-FP-2.5D and (18)F-FP-2.5F enabled integrin-specific PET imaging of U87MG tumors with good imaging contrasts. (18)F-FP-2.5D demonstrated more desirable pharmacokinetics compared to (18)F-FP-2.5F, and thus has greater potential for clinical translation.

    View details for DOI 10.7150/thno/v01p0403

    View details for Web of Science ID 000299121000034

    View details for PubMedID 22211146

    View details for PubMedCentralID PMC3248644

  • Dynamic transition between Zn-HDS and ZnO; growth and dissolving mechanism of dumbbell-like ZnO bipod crystal CRYSTENGCOMM Jang, E., Won, J., Kim, Y., Cheng, Z., Choy, J. 2011; 13 (2): 546-552

    View details for DOI 10.1039/c003458d

    View details for Web of Science ID 000285514000028

  • Recent Progress in Radiofluorination of Peptides for PET Molecular Imaging Current Organic Synthesis Liu S, S. C. 2011; 8 (4): 584-592
  • Molecular Probes for Bioluminescence Imaging Current Organic Synthesis Wu S, C. C. 2011; 8 (4): 488-497
  • Radiofluorinated Rhenium Cyclized alpha-MSH Analogues for PET Imaging of Melanocortin Receptor 1 BIOCONJUGATE CHEMISTRY Ren, G., Liu, S., Liu, H., Miao, Z., Cheng, Z. 2010; 21 (12): 2355-2360


    In order to accomplish in vivo molecular imaging of melanoma biomarker melanocortin 1 receptor (MC1R), several α-melanocyte-stimulating hormone (α-MSH) analogues have been labeled with N-succinimidyl-4-¹⁸F-fluorobenzoate (¹⁸)F-SFB) and studied as positron emission tomography (PET) probes in our recent studies. To further pursue a radiofluorinated α-MSH peptide with high clinical translation potential, we utilized 4-nitrophenyl 2-¹⁸F-fluoropropionate (¹⁸F-NFP) to radiofluorinate the transition metal rhenium cyclized α-MSH metallopeptides for PET imaging of MC1R positive malignant melanoma. Metallopeptides Ac-d,Lys-ReCCMSH(Arg¹¹) (two isomers, namely RMSH-1 and RMSH-2) were synthesized using conventional solid phase peptide synthesis chemistry and rhenium cyclization reaction. The two isomers were then conjugated with ¹⁹F-NFP or ¹⁸F-NFP. The resulting cold or radiofluorinated metallopeptides, (¹⁸/¹⁹)F-FP-RMSH-1 and (¹⁸/¹⁹)F-FP-RMSH-2, were further evaluated for their in vitro receptor binding affinities, in vivo biodistribution, and small-animal PET imaging properties. The binding affinities of ¹⁹F-FP-RMSH-1 and ¹⁹F-FP-RMSH-2 were determined to be within low nanomolar range. In vivo studies revealed that both F-labeled metallopeptides possessed good tumor uptake in the B16F10 murine model with high MC1R expression, while possessing much lower uptake in A375M human melanoma xenografts. Moreover, ¹⁸F-FP-RMSH-1 displayed more favorable in vivo performance in terms of higher tumor uptake and much lower accumulation in the kidney and liver, when compared to that of ¹⁸F-FP-RMSH-2 at 2 h postinjection (p.i.). ¹⁸F-FP-RMSH-1 also displayed lower liver and lung uptake when compared with that of the same peptide labeled with ¹⁸F-SFB (named as ¹⁸F-FB-RMSH-1). Small animal PET imaging of ¹⁸F-FP-RMSH-1 in mice bearing B16F10 tumors at 1 and 2 h showed good tumor imaging quality. As expected, much lower tumor uptake and poorer tumor/normal organ contrast were observed for A375M model compared to those of the B16F10 model. ¹⁸F-FP-RMSH-1 also exhibited higher tumor uptake and better tumor retention when compared with ¹⁸F-FB-RMSH-1. ¹⁸F-FP-RMSH-1 demonstrates significant advantages over ¹⁸F-FB-RMSH-1 and ¹⁸F-FP-RMSH-2. It is a promising PET probe for imaging MC1R positive melanoma and MC1R expression in vivo.

    View details for DOI 10.1021/bc100391a

    View details for Web of Science ID 000285236300029

    View details for PubMedID 21073170

    View details for PubMedCentralID PMC3046310

  • Effects of Nanoparticle Size on Cellular Uptake and Liver MRI with Polyvinylpyrrolidone-Coated Iron Oxide Nanoparticles ACS NANO Huang, J., Bu, L., Xie, J., Chen, K., Cheng, Z., Li, X., Chen, X. 2010; 4 (12): 7151-7160


    The effect of nanoparticle size (30-120 nm) on magnetic resonance imaging (MRI) of hepatic lesions in vivo has been systematically examined using polyvinylpyrrolidone (PVP)-coated iron oxide nanoparticles (PVP-IOs). Such biocompatible PVP-IOs with different sizes were synthesized by a simple one-pot pyrolysis method. These PVP-IOs exhibited good crystallinity and high T(2) relaxivities, and the relaxivity increased with the size of the magnetic nanoparticles. It was found that cellular uptake changed with both size and surface physiochemical properties, and that PVP-IO-37 with a core size of 37 nm and hydrodynamic particle size of 100 nm exhibited higher cellular uptake rate and greater distribution than other PVP-IOs and Feridex. We systematically investigated the effect of nanoparticle size on MRI of normal liver and hepatic lesions in vivo. The physical and chemical properties of the nanoparticles influenced their pharmacokinetic behavior, which ultimately determined their ability to accumulate in the liver. The contrast enhancement of PVP-IOs within the liver was highly dependent on the overall size of the nanoparticles, and the 100 nm PVP-IO-37 nanoparticles exhibited the greatest enhancement. These results will have implications in designing engineered nanoparticles that are optimized as MR contrast agents or for use in therapeutics.

    View details for DOI 10.1021/nn101643u

    View details for Web of Science ID 000285449100015

    View details for PubMedID 21043459

    View details for PubMedCentralID PMC3011031

  • Near-infrared fluorescent nanoprobes for cancer molecular imaging: status and challenges TRENDS IN MOLECULAR MEDICINE He, X., Gao, J., Gambhir, S. S., Cheng, Z. 2010; 16 (12): 574-583


    Near-infrared fluorescence (NIRF) imaging promises to improve cancer imaging and management; advances in nanomaterials allow scientists to combine new nanoparticles with NIRF imaging techniques, thereby fulfilling this promise. Here, we present a synopsis of current developments in NIRF nanoprobes, their use in imaging small living subjects, their pharmacokinetics and toxicity, and finally their integration into multimodal imaging strategies. We also discuss challenges impeding the clinical translation of NIRF nanoprobes for molecular imaging of cancer. Whereas utilization of most NIRF nanoprobes remains at a proof-of-principle stage, optimizing the impact of nanomedicine in cancer patient diagnosis and management will probably be realized through persistent interdisciplinary amalgamation of diverse research fields.

    View details for DOI 10.1016/j.molmed.2010.08.006

    View details for Web of Science ID 000285727200004

    View details for PubMedID 20870460

    View details for PubMedCentralID PMC2994979

  • PET Imaging of Tumor Neovascularization in a Transgenic Mouse Model with a Novel Cu-64-DOTA-Knottin Peptide CANCER RESEARCH Nielsen, C. H., Kimura, R. H., Withofs, N., Tran, P. T., Miao, Z., Cochran, J. R., Cheng, Z., Felsher, D., Kjaer, A., Willmann, J. K., Gambhir, S. S. 2010; 70 (22): 9022-9030


    Due to the high mortality of lung cancer, there is a critical need to develop diagnostic procedures enabling early detection of the disease while at a curable stage. Targeted molecular imaging builds on the positive attributes of positron emission tomography/computed tomography (PET/CT) to allow for a noninvasive detection and characterization of smaller lung nodules, thus increasing the chances of positive treatment outcome. In this study, we investigate the ability to characterize lung tumors that spontaneously arise in a transgenic mouse model. The tumors are first identified with small animal CT followed by characterization with the use of small animal PET with a novel 64Cu-1,4,7,10-tetra-azacylododecane-N,N',N'',N'''-tetraacetic acid (DOTA)-knottin peptide that targets integrins upregulated during angiogenesis on the tumor associated neovasculature. The imaging results obtained with the knottin peptide are compared with standard 18F-fluorodeoxyglucose (FDG) PET small animal imaging. Lung nodules as small as 3 mm in diameter were successfully identified in the transgenic mice by small animal CT, and both 64Cu-DOTA-knottin 2.5F and FDG were able to differentiate lung nodules from the surrounding tissues. Uptake and retention of the 64Cu-DOTA-knottin 2.5F tracer in the lung tumors combined with a low background in the thorax resulted in a statistically higher tumor to background (normal lung) ratio compared with FDG (6.01±0.61 versus 4.36±0.68; P<0.05). Ex vivo biodistribution showed 64Cu-DOTA-knottin 2.5F to have a fast renal clearance combined with low nonspecific accumulation in the thorax. Collectively, these results show 64Cu-DOTA-knottin 2.5F to be a promising candidate for clinical translation for earlier detection and improved characterization of lung cancer.

    View details for DOI 10.1158/0008-5472.CAN-10-1338

    View details for Web of Science ID 000284213300008

    View details for PubMedID 21062977

    View details for PubMedCentralID PMC3057960

  • Optical imaging of reporter gene expression using a positron-emission-tomography probe JOURNAL OF BIOMEDICAL OPTICS Liu, H., Ren, G., Liu, S., Zhang, X., Chen, L., Han, P., Cheng, Z. 2010; 15 (6)


    Reporter gene∕reporter probe technology is one of the most important techniques in molecular imaging. Lately, many reporter gene∕reporter probe systems have been coupled to different imaging modalities such as positron emission tomography (PET) and optical imaging (OI). It has been recently found that OI techniques could be used to monitor radioactive tracers in vitro and in living subjects. In this study, we further demonstrate that a reporter gene∕nuclear reporter probe system [herpes simplex virus type-1 thymidine kinase (HSV1-tk) and 9-(4-(18)F-fluoro-3-[hydroxymethyl] butyl) guanine ([(18)F]FHBG)] could be successfully imaged by OI in vitro and in vivo. OI with radioactive reporter probes will facilitate and broaden the applications of reporter gene∕reporter probe techniques in medical research.

    View details for DOI 10.1117/1.3514659

    View details for Web of Science ID 000287171100005

    View details for PubMedID 21198146

    View details for PubMedCentralID PMC3003718

  • Dynamic Visualization of RGD-Quantum Dot Binding to Tumor Neovasculature and Extravasation in Multiple Living Mouse Models Using Intravital Microscopy SMALL Smith, B. R., Cheng, Z., De, A., Rosenberg, J., Gambhir, S. S. 2010; 6 (20): 2222-2229

    View details for DOI 10.1002/smll.201001022

    View details for Web of Science ID 000283890500003

    View details for PubMedID 20862677

    View details for PubMedCentralID PMC3030963

  • Molecular Probes for Malignant Melanoma Imaging CURRENT PHARMACEUTICAL BIOTECHNOLOGY Ren, G., Pan, Y., Cheng, Z. 2010; 11 (6): 590-602


    Malignant melanoma represents a serious public health problem and is a deadly disease when it is diagnosed at late stage. Though (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) has been widely used clinically for melanoma imaging, other approaches to specifically identify, characterize, monitor and guide therapeutics for malignant melanoma are still needed. Consequently, many probes targeting general molecular events including metabolism, angiogenesis, hypoxia and apoptosis in melanoma have been successfully developed. Furthermore, probes targeting melanoma associated targets such as melanocortin receptor 1 (MC1R), melanin, etc. have undergone active investigation and have demonstrated high melanoma specificity. In this review, these molecular probes targeting diverse melanoma biomarkers have been summarized. Some of them may eventually contribute to the improvement of personalized management of malignant melanoma.

    View details for Web of Science ID 000281435100006

    View details for PubMedID 20497118

  • Near-Infrared Quantum Dots as Optical Probes for Tumor Imaging CURRENT TOPICS IN MEDICINAL CHEMISTRY Gao, J., Chen, X., Cheng, Z. 2010; 10 (12): 1147-1157


    Molecular imaging plays a key role in personalized medicine, which is the goal and future of patient management. Among the various molecular imaging modalities, optical imaging may be the fastest growing area for bioanalysis, and the major reason is the research on fluorescence semiconductor quantum dots (QDs) and dyes have evolved over the past two decades. The great efforts on the synthesis of QDs with fluorescence emission from UV to near-infrared (NIR) regions speed up the studies of QDs as optical probes for in vitro and in vivo molecular imaging. For in vivo applications, the fluorescent emission wavelength ideally should be in a region of the spectrum where blood and tissue absorb minimally and tissue penetration reach maximally, which is NIR region (typically 700-1000 nm). The goal of this review is to provide readers the basics of NIR-emitting QDs, the bioconjugate chemistry of QDs, and their applications for diagnostic tumor imaging. We will also discuss the benefits, challenges, limitations, perspective, and the future scope of NIR-emitting QDs for tumor imaging applications.

    View details for Web of Science ID 000279117800002

    View details for PubMedID 20388111

  • In vivo near-infrared fluorescence imaging of cancer with nanoparticle-based probes WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY He, X., Wang, K., Cheng, Z. 2010; 2 (4): 349-366


    The use of in vivo near-infrared fluorescence (NIRF) imaging techniques for sensitive cancer early detection is highly desirable, because biological tissues show very low absorption and autofluorescence in the NIR spectrum window. Cancer NIRF molecular imaging relies greatly on stable, highly specific and sensitive molecular probes. Nanoparticle-based NIRF probes have overcome some of the limitations of the conventional NIRF organic dyes, such as poor hydrophilicity and photostability, low quantum yield, insufficient stability in biological system, low detection sensitivity, etc. Therefore, a lot of efforts have been made to actively develop novel NIRF nanoparticles for in vivo cancer molecular imaging. The main focus of this article is to provide a brief overview of the synthesis, surface modification, and in vivo cancer imaging applications of nanoparticle-based NIRF probes, including dye-containing nanoparticles, NIRF quantum dots, and upconversion nanoparticles.

    View details for DOI 10.1002/wnan.85

    View details for Web of Science ID 000280014000003

    View details for PubMedID 20564463

  • Cu-64-Labeled Affibody Molecules for Imaging of HER2 Expressing Tumors MOLECULAR IMAGING AND BIOLOGY Cheng, Z., De Jesus, O. P., Kramer, D. J., De, A., Webster, J. M., Gheysens, O., Levi, J., Namavari, M., Wang, S., Park, J. M., Zhang, R., Liu, H., Lee, B., Syud, F. A., Gambhir, S. S. 2010; 12 (3): 316-324


    The development of molecular probes based on novel engineered protein constructs is under active investigation due to the great potential of this generalizable strategy for imaging a variety of tumor targets.In this report, human epidermal growth factor receptor type 2 (HER2)-binding Affibody molecules were radiolabeled with (64)Cu and their imaging ability was further evaluated in tumor mice models to understand the promise and limitations of such probes. The anti-HER2 Affibody molecules in monomeric (Z(HER2:477)) and dimeric [(Z(HER2:477))(2)] forms were site specifically modified with the maleimide-functionalized chelator, 1,4,7,10-tetraazacyclododecane-1,4,7-tris(acetic acid)-10-acetate mono (N-ethylmaleimide amide) (Mal-DOTA). The resulting DOTA-Affibody conjugates were radiolabeled with (64)Cu and evaluated in nude mice bearing subcutaneous SKOV3 tumors. Biodistribution experiments showed that tumor uptake values of (64)Cu-DOTA-Z(HER2:477) and (64)Cu-DOTA-(Z(HER2:477))(2) were 6.12 +/- 1.44% and 1.46 +/- 0.50% ID/g, respectively, in nude mice (n = 3 each) at 4 h postinjection. Moreover, (64)Cu-labeled monomer exhibited significantly higher tumor/blood ratio than that of radiolabeled dimeric counterpart at all time points examined in this study. MicroPET imaging of (64)Cu-DOTA-Z(HER2:477) in SKOV3 tumor mice clearly showed good and specific tumor localization. This study demonstrates that (64)Cu-labeled Z(HER2:477) is a promising targeted molecular probe for imaging HER2 receptor expression in living mice. Further work is needed to improve the excretion properties, hence dosimetry and imaging efficacy, of the radiometal-based probe.

    View details for DOI 10.1007/s11307-009-0256-6

    View details for Web of Science ID 000277375300010

    View details for PubMedID 19779897

  • Radiation-Luminescence-Excited Quantum Dots for in vivo Multiplexed Optical Imaging SMALL Liu, H., Zhang, X., Xing, B., Han, P., Gambhir, S. S., Cheng, Z. 2010; 6 (10): 1087-1091

    View details for DOI 10.1002/smll.200902408

    View details for Web of Science ID 000278629300004

    View details for PubMedID 20473988

  • Cy5.5-labeled Affibody molecule for near-infrared fluorescent optical imaging of epidermal growth factor receptor positive tumors JOURNAL OF BIOMEDICAL OPTICS Miao, Z., Ren, G., Liu, H., Jiang, L., Cheng, Z. 2010; 15 (3)


    Affibody protein is an engineered protein scaffold with a three-helical bundle structure. Affibody molecules of small size (7 kD) have great potential for targeting overexpressed cancer biomarkers in vivo. To develop an Affibody-based molecular probe for in vivo optical imaging of epidermal growth factor receptor (EGFR) positive tumors, an anti-EGFR Affibody molecule, Ac-Cys-Z(EGFR:1907) (7 kD), is site-specifically conjugated with a near-IR fluorescence dye, Cy5.5-mono-maleimide. Using fluorescent microscopy, the binding specificity of the probe Cy5.5-Z(EGFR:1907) is checked by a high-EGFR-expressing A431 cell and low-EGFR-expressing MCF7 cells. The binding affinity of Cy5.5-Z(EGFR:1907) (K(D)) to EGFR is 43.6+/-8.4 nM, as determined by flow cytometry. For an in vivo imaging study, the probe shows fast tumor targeting and good tumor contrast as early as 0.5 h postinjection (p.i.) for A431 tumors, while MCF7 tumors are barely visible. An ex vivo imaging study also demonstrates that Cy5.5-Z(EGFR:1907) has high tumor, liver, and kidney uptakes at 24 h p.i.. In conclusion, Cy5.5-Z(EGFR:1907) shows good affinity and high specificity to the EGFR. There is rapid achievement of good tumor-to-normal-tissue contrasts of Cy5.5-Z(EGFR:1907), thus demonstrating its potential for EGFR-targeted molecular imaging of cancers.

    View details for DOI 10.1117/1.3432738

    View details for Web of Science ID 000280642900022

    View details for PubMedID 20615009

  • Small-Animal PET Imaging of Human Epidermal Growth Factor Receptor Positive Tumor with a Cu-64 Labeled Affibody Protein BIOCONJUGATE CHEMISTRY Miao, Z., Ren, G., Liu, H., Jiang, L., Cheng, Z. 2010; 21 (5): 947-954


    Epidermal growth factor receptor (EGFR) has become an attractive target for cancer molecular imaging and therapy. Affibody proteins against EGFR have been reported, and thus, we were interested in evaluating their potential for positron emission tomography (PET) imaging of EGFR positive cancer. An Affibody analogue (Ac-Cys-Z(EGFR:1907)) binding to EGFR was made through conventional solid phase peptide synthesis. The purified protein was site-specifically coupled with the 1,4,7,10-tetraazacyclododecane-1,4,7-tris-aceticacid-10-maleimidethylacetamide (maleimido-mono-amide-DOTA) to produce the bioconjugate, DOTA-Z(EGFR:1907). (64)Cu labeled probe (64)Cu-DOTA-Z(EGFR:1907) displayed a moderate specific activity (5-8 MBq/nmol, 22-35 microCi/microg). Cell uptake assays by pre-incubating without or with 300 times excess unlabeled Ac-Cys-Z(EGFR:1907) showed high EGFR-specific uptake (20% applied activity at 0.5 h) in A431 epidermoid carcinoma cancer cells. The affinity (K(D)) of (64)Cu-DOTA-Z(EGFR:1907) as tested by cell saturation analysis was 20 nM. The serum stability test showed excellent stability of the probe with >95% intact after 4 h of incubation in mouse serum. In vivo small-animal PET imaging showed fast tumor targeting, high tumor accumulation (approximately 10% ID/g at 1 h p.i.), and good tumor-to-normal tissue contrast of (64)Cu-DOTA-Z(EGFR:1907) spiked with a wide dose range of Ac-Cys-Z(EGFR:1907). Bio-distribution studies further demonstrated that the probe had high tumor, blood, liver, and kidney uptakes, while blood radioactivity concentration dropped dramatically at increased spiking doses. Co-injection of the probe with 500 microg of Ac-Cys-Z(EGFR:1907) for blocking significantly reduced the tumor uptake. Thus, (64)Cu-DOTA-Z(EGFR:1907) showed potential as a high tumor contrast EGFR PET imaging reagent. The probe spiked with 50 microg of Ac-Cys-Z(EGFR:1907) improved tumor imaging contrast which may have important clinical applications.

    View details for DOI 10.1021/bc900515p

    View details for Web of Science ID 000277683300020

    View details for PubMedID 20402512

  • In Vivo Tumor-Targeted Fluorescence Imaging Using Near-Infrared Non-Cadmium Quantum Dots BIOCONJUGATE CHEMISTRY Gao, J., Chen, K., Xie, R., Xie, J., Yan, Y., Cheng, Z., Peng, X., Chen, X. 2010; 21 (4): 604-609


    This article reported the high tumor targeting efficacy of RGD peptide labeled near-infrared (NIR) non-cadmium quantum dots (QDs). After using poly(ethylene glycol) to encapsulate InAs/InP/ZnSe QDs (emission maximum at about 800 nm), QD800-PEG dispersed well in PBS buffer with the hydrodynamic diameter (HD) of 15.9 nm and the circulation half-life of approximately 29 min. After coupling QD800-PEG with arginine-glycine-aspartic acid (RGD) or arginine-alanine-aspartic acid (RAD) peptides, we used nude mice bearing subcutaneous U87MG tumor as models to test tumor-targeted fluorescence imaging. The results indicated that the tumor uptake of QD800-RGD is much higher than those of QD800-PEG and QD800-RAD. The semiquantitative analysis of the region of interest (ROI) showed a high tumor uptake of 10.7 +/- 1.5%ID/g in mice injected with QD800-RGD, while the tumor uptakes of QD800-PEG and QD800-RAD were 2.9 +/- 0.3%ID/g and 4.0 +/- 0.5%ID/g, respectively, indicating the specific tumor targeting of QD800-RGD. The high reproducibility of bioconjunction between QDs and the RGD peptide and the feasibility of QD-RGD bioconjugates as tumor-targeted fluorescence probes warrant the successful application of QDs for in vivo molecular imaging.

    View details for DOI 10.1021/bc900323v

    View details for Web of Science ID 000276817800006

    View details for PubMedID 20369817

    View details for PubMedCentralID PMC3617504

  • Molecular Optical Imaging with Radioactive Probes PLOS ONE Liu, H., Ren, G., Miao, Z., Zhang, X., Tang, X., Han, P., Gambhir, S. S., Cheng, Z. 2010; 5 (3)


    Optical imaging (OI) techniques such as bioluminescence and fluorescence imaging have been widely used to track diseases in a non-invasive manner within living subjects. These techniques generally require bioluminescent and fluorescent probes. Here we demonstrate the feasibility of using radioactive probes for in vivo molecular OI.By taking the advantages of low energy window of light (1.2-3.1 eV, 400-1000 nm) resulting from radiation, radionuclides that emit charged particles such as beta(+) and beta(-) can be successfully imaged with an OI instrument. In vivo optical images can be obtained for several radioactive probes including 2-deoxy-2-[(18)F]fluoro-D-glucose ([(18)F]FDG), Na(18)F, Na(131)I, (90)YCl(3) and a (90)Y labeled peptide that specifically target tumors.These studies demonstrate generalizability of radioactive OI technique. It provides a new molecular imaging strategy and will likely have significant impact on both small animal and clinical imaging.

    View details for DOI 10.1371/journal.pone.0009470

    View details for Web of Science ID 000274997100016

    View details for PubMedID 20208993

    View details for PubMedCentralID PMC2830426

  • A Dual-Labeled Knottin Peptide for PET and Near-Infrared Fluorescence Imaging of Integrin Expression in Living Subjects BIOCONJUGATE CHEMISTRY Kimura, R. H., Miao, Z., Cheng, Z., Gambhir, S. S., Cochran, J. R. 2010; 21 (3): 436-444


    Previously, we used directed evolution to engineer mutants of the Ecballium elaterium trypsin inhibitor (EETI-II) knottin that bind to alpha(v)beta(3) and alpha(v)beta(5) integrin receptors with low nanomolar affinity, and showed that Cy5.5- or (64)Cu-DOTA-labeled knottin peptides could be used to image integrin expression in mouse tumor models using near-infrared fluorescence (NIRF) imaging or positron emission tomography (PET). Here, we report the development of a dual-labeled knottin peptide conjugated to both NIRF and PET imaging agents for multimodality imaging in living subjects. We created an orthogonally protected peptide-based linker for stoichiometric coupling of (64)Cu-DOTA and Cy5.5 onto the knottin N-terminus and confirmed that conjugation did not affect binding to alpha(v)beta(3) and alpha(v)beta(5) integrins. NIRF and PET imaging studies in tumor xenograft models showed that Cy5.5 conjugation significantly increased kidney uptake and retention compared to the knottin peptide labeled with (64)Cu-DOTA alone. In the tumor, the dual-labeled (64)Cu-DOTA/Cy5.5 knottin peptide showed decreased wash-out leading to significantly better retention (p < 0.05) compared to the (64)Cu-DOTA-labeled knottin peptide. Tumor uptake was significantly reduced (p < 0.05) when the dual-labeled knottin peptide was coinjected with an excess of unlabeled competitor and when tested in a tumor model with lower levels of integrin expression. Finally, plots of tumor-to-background tissue ratios for Cy5.5 versus (64)Cu uptake were well-correlated over several time points post injection, demonstrating pharmacokinetic cross validation of imaging labels. This dual-modality NIRF/PET imaging agent is promising for further development in clinical applications where high sensitivity and high resolution are desired, such as detection of tumors located deep within the body and image-guided surgical resection.

    View details for DOI 10.1021/bc9003102

    View details for Web of Science ID 000275711600004

    View details for PubMedCentralID PMC3004996

  • Evaluation of a Cu-64-Labeled Cystine-Knot Peptide Based on Agouti-Related Protein for PET of Tumors Expressing alpha(v)beta(3) Integrin JOURNAL OF NUCLEAR MEDICINE Jiang, L., Kimura, R. H., Miao, Z., Silverman, A. P., Ren, G., Liu, H., Li, P., Gambhir, S. S., Cochran, J. R., Cheng, Z. 2010; 51 (2): 251-258


    Recently, a truncated form of the agouti-related protein (AgRP), a 4-kDa cystine-knot peptide of human origin, was used as a scaffold to engineer mutants that bound to alpha(v)beta(3) integrin with high affinity and specificity. In this study, we evaluated the potential of engineered integrin-binding AgRP peptides for use as cancer imaging agents in living subjects.Engineered AgRP peptides were prepared by solid-phase peptide synthesis and were folded in vitro and purified by reversed-phase high-performance liquid chromatography. Competition assays were used to measure the relative binding affinities of engineered AgRP peptides for integrin receptors expressed on the surface of U87MG glioblastoma cells. The highest-affinity mutant, AgRP clone 7C, was site-specifically conjugated with 1,4,7,10-tetra-azacyclododecane-N,N',N''N'''-tetraacetic acid (DOTA). The resulting bioconjugate, DOTA-AgRP-7C, was radiolabeled with (64)Cu for biodistribution analysis and small-animal PET studies in mice bearing U87MG tumor xenografts. In addition to serum stability, the in vivo metabolic stability of (64)Cu-DOTA-AgRP-7C was assessed after injection and probe recovery from mouse kidney, liver, tumor, and urine.AgRP-7C and DOTA-AgRP-7C bound with high affinity to integrin receptors expressed on U87MG cells (half maximal inhibitory concentration values, 20 +/- 4 and 14 +/- 2 nM, respectively). DOTA-AgRP-7C was labeled with (64)Cu with high radiochemical purity (>99%). In biodistribution and small-animal PET studies, (64)Cu-DOTA-AgRP-7C displayed rapid blood clearance, good tumor uptake and retention (2.70 +/- 0.93 percentage injected dose per gram [%ID/g] and 2.37 +/- 1.04 %ID/g at 2 and 24 h, respectively), and high tumor-to-background tissue ratios. The integrin-binding specificity of (64)Cu-DOTA-AgRP-7C was confirmed in vitro and in vivo by showing that a large molar excess of the unlabeled peptidomimetic c(RGDyK) could block probe binding and tumor uptake. Serum stability and in vivo metabolite assays demonstrated that engineered AgRP peptides are sufficiently stable for in vivo molecular imaging applications.A radiolabeled version of the engineered AgRP peptide 7C showed promise as a PET agent for tumors that express the alpha(v)beta(3) integrin. Collectively, these results validate AgRP-based cystine-knot peptides for use in vivo as molecular imaging agents and provide support for the general use of AgRP as a scaffold to develop targeting peptides, and hence diagnostics, against other tumor receptors.

    View details for DOI 10.2967/jnumed.109.069831

    View details for Web of Science ID 000274152800028

    View details for PubMedID 20124048

  • Ultrasmall Near-Infrared Non-cadmium Quantum Dots for in vivo Tumor Imaging SMALL Gao, J., Chen, K., Xie, R., Xie, J., Lee, S., Cheng, Z., Peng, X., Chen, X. 2010; 6 (2): 256-261


    The high tumor uptake of ultrasmall near-infrared quantum dots (QDs) attributed to the enhanced permeability and retention effect is reported. InAs/InP/ZnSe QDs coated by mercaptopropionic acid (MPA) exhibit an emission wavelength of about 800 nm (QD800-MPA) with very small hydrodynamic diameter (<10 nm). Using 22B and LS174T tumor xenograft models, in vivo and ex vivo imaging studies show that QD800-MPA is highly accumulated in the tumor area, which is very promising for tumor detection in living mice. The ex vivo elemental analysis (Indium) using inductively coupled plasma (ICP) spectrometry confirm the tumor uptake of QDs. The ICP data are consistent with the in vivo and ex vivo fluorescence imaging. Human serum albumin (HSA)-coated QD800-MPA nanoparticles (QD800-MPA-HSA) show reduced localization in mononuclear phagocytic system-related organs over QD800-MPA plausibly due to the low uptake of QD800-MPA-HSA in macrophage cells. QD800-MPA-HSA may have great potential for in vivo fluorescence imaging.

    View details for DOI 10.1002/smll.200901672

    View details for Web of Science ID 000274363800018

    View details for PubMedID 19911392

    View details for PubMedCentralID PMC2860770

  • HSA coated MnO nanoparticles with prominent MRI contrast for tumor imaging CHEMICAL COMMUNICATIONS Huang, J., Xie, J., Chen, K., Bu, L., Lee, S., Cheng, Z., Li, X., Chen, X. 2010; 46 (36): 6684-6686


    We report in this Communication a facile, two-step surface modification strategy to achieve manganese oxide nanoparticles with prominent MRI T1 contrast. In a U87MG glioblastoma xenograft model, we confirmed that the particles can accumulate efficiently in tumor area to induce effective T1 signal alteration.

    View details for DOI 10.1039/c0cc01041c

    View details for Web of Science ID 000281604500010

    View details for PubMedID 20730157

    View details for PubMedCentralID PMC3629962

  • Synthesis of porous and nonporous ZnO nanobelt, multipod, and hierarchical nanostructure from Zn-HDS J Solid State Chem Jang ES, W. K. 2010; 183 (8): Available online 2 J
  • An Engineered Knottin Peptide Labeled with F-18 for PET Imaging of Integrin Expression BIOCONJUGATE CHEMISTRY Miao, Z., Ren, G., Liu, H., Kimura, R. H., Jiang, L., Cochran, J. R., Gambhir, S. S., Cheng, Z. 2009; 20 (12): 2342-2347


    Knottins are small constrained polypeptides that share a common disulfide-bonded framework and a triple-stranded beta-sheet fold. Previously, directed evolution of the Ecballium elaterium trypsin inhibitor (EETI-II) knottin led to the identification of a mutant that bound to tumor-specific alpha(v)beta(3) and alpha(v)beta(5) integrin receptors with low nanomolar affinity. The objective of this study was to prepare and evaluate a radiofluorinated version of this knottin (termed 2.5D) for microPET imaging of integrin positive tumors in living subjects. Knottin peptide 2.5D was prepared by solid-phase synthesis and folded in vitro, and its free N-terminal amine was reacted with N-succinimidyl-4-18/19F-fluorobenzoate (18/19F-SFB) to produce the fluorinated peptide 18/19F-FB-2.5D. The binding affinities of unlabeled knottin peptide 2.5D and 19F-FB-2.5D to U87MG glioblastoma cells were measured by competition binding assay using 125I-labeled echistatin. It was found that unlabeled 2.5D and 19F-FB-2.5D competed with 125I-echistatin for binding to cell surface integrins with IC(50) values of 20.3 +/- 7.3 and 13.2 +/- 5.4 nM, respectively. Radiosynthesis of 18F-FB-2.5D resulted in a product with high specific activity (ca. 100 GBq/micromol). Next, biodistribution and positron emission tomography (PET) imaging studies were performed to evaluate the in vivo behavior of 18F-FB-2.5D. Approximately 3.7 MBq 18F-FB-2.5D was injected into U87MG tumor-bearing mice via the tail vein. Biodistribution studies demonstrated that 18F-FB-2.5D had moderate tumor uptake at 0.5 h post injection, and coinjection of a large excess of the unlabeled peptidomimetic c(RGDyK) as a blocking agent significantly reduced tumor uptake (1.90 +/- 1.15 vs 0.57 +/- 0.14%ID/g, 70% inhibition, P < 0.05). In vivo microPET imaging showed that 18F-FB-2.5D rapidly accumulated in the tumor and quickly cleared from the blood through the kidneys, allowing excellent tumor-to-normal tissue contrast to be obtained. Collectively, 18F-FB-2.5D allows integrin-specific PET imaging of U87MG tumors with good contrast and further demonstrates that knottins are excellent peptide scaffolds for development of PET probes with potential for clinical translation.

    View details for DOI 10.1021/bc900361g

    View details for Web of Science ID 000272690100018

    View details for PubMedID 19908826

    View details for PubMedCentralID PMC2804269

  • PET of Malignant Melanoma Using F-18-Labeled Metallopeptides JOURNAL OF NUCLEAR MEDICINE Ren, G., Liu, Z., Miao, Z., Liu, H., Subbarayan, M., Chin, F. T., Zhang, L., Gambhir, S. S., Cheng, Z. 2009; 50 (11): 1865-1872


    Melanocortin type 1 receptor (MC1R), also known as alpha-melanocyte-stimulating hormone (alpha-MSH) receptor, is an attractive molecular target for melanoma imaging and therapy. An (18)F-labeled linear alpha-MSH peptide ((18)F-FB-Ac-Nle-Asp-His-d-Phe-Arg-Trp-Gly-Lys-NH(2) [NAPamide]) shows promising melanoma imaging properties but with only moderate tumor uptake and retention. A transition metal rhenium-cyclized alpha-MSH peptide, ReO[Cys(3,4,10),d-Phe(7),Arg(11)]alpha-MSH(3-13) (ReCCMSH(Arg(11))), has shown high in vitro binding affinity to MC1R and excellent in vivo melanoma-targeting profiles when labeled with radiometals. Therefore, we hypothesized that ReCCMSH(Arg(11)) could be a good platform for the further development of an (18)F-labeled probe for PET of MC1R-positive malignant melanoma.In this study, the metallopeptide Ac-d-Lys-ReCCMSH(Arg(11)) was synthesized using conventional solid-phase peptide synthesis chemistry and a rhenium cyclization reaction. The resulting peptides were then labeled with N-succinimidyl-4-(18)F-fluorobenzoate ((18)F-SFB). The (18)F-labeled metallopeptides were further tested for their in vitro receptor binding affinities, in vivo biodistribution, and PET imaging properties.Both isomers of Ac-d-Lys-ReCCMSH(Arg(11)), named as RMSH-1 and RMSH-2, were purified and identified by high-performance liquid chromatography. The binding affinities of RMSH-1 and RMSH-2 and their respective (19)F-SFB-conjugated peptides ((19)F-FB-RMSH-1 and (19)F-FB-RMSH-2) were all determined to be within nanomolar range. Both (18)F-labeled metallopeptides showed good tumor uptake in the B16F10 murine model, with high MC1R expression, but much lower uptake in the A375M human melanoma xenografted in mice, indicating low MC1R expression. (18)F-FB-RMSH-1, when compared with (18)F-FB-RMSH-2, displayed more favorable in vivo performance in terms of slightly higher tumor uptakes and much lower accumulations in the kidney and liver at 2 h after injection. Small-animal PET of (18)F-FB-RMSH-1 and -2 in mice bearing B16F10 tumors at 1 and 2 h showed good tumor imaging quality. As expected, much lower tumor uptakes and poorer tumor-to-normal organ contrasts were observed for the A375M model than for the B16F10 model. (18)F-FB-RMSH-1 and -2 showed higher tumor uptake and better tumor retention than did (18)F-FB-NAPamide.Specific in vivo targeting of (18)F-FB-RMSH-1 to malignant melanoma was successfully achieved in preclinical models with high MC1R expression. Thus, the radiofluorinated metallopeptide (18)F-FB-RMSH-1 is a promising molecular probe for PET of MC1R-positive tumors.

    View details for DOI 10.2967/jnumed.109.062877

    View details for Web of Science ID 000272554100021

    View details for PubMedID 19837749

  • Melanin-Targeted Preclinical PET Imaging of Melanoma Metastasis JOURNAL OF NUCLEAR MEDICINE Ren, G., Miao, Z., Liu, H., Jiang, L., Limpa-Amara, N., Mahmood, A., Gambhir, S. S., Cheng, Z. 2009; 50 (10): 1692-1699


    Dialkylamino-alkyl-benzamides possess an affinity for melanin, suggesting that labeling of such benzamides with (18)F could potentially produce melanin-targeted PET probes able to identify melanotic melanoma metastases in vivo with high sensitivity and specificity.In this study, N-[2-(diethylamino)ethyl]-4-(18)F-fluorobenzamide ((18)F-FBZA) was synthesized via a 1-step conjugation reaction. The sigma-receptor binding affinity of (19)F-FBZA was determined along with the in vitro cellular uptake of radiofluorinated (18)F-FBZA in B16F10 cells. In vivo distribution and small-animal PET studies were conducted on mice bearing B16F10 melanoma, A375M amelanotic melanoma, and U87MG tumors, and comparative studies were performed with (18)F-FDG PET in the melanoma models.In vitro, uptake of (18)F-FBZA was significantly higher in B16F10 cells treated with l-tyrosine (P < 0.001). In vivo, (18)F-FBZA displayed significant tumor uptake; at 2 h, 5.94 +/- 1.83 percentage injected dose (%ID) per gram was observed in B16F10 tumors and only 0.75 +/- 0.09 %ID/g and 0.56 +/- 0.13 %ID/g was observed in amelanotic A375M and U87MG tumors, respectively. Lung uptake was significantly higher in murine lungs bearing melanotic B16F10 pulmonary metastases than in normal murine lungs (P < 0.01). Small-animal PET clearly identified melanotic lesions in both primary and pulmonary metastasis B16F10 tumor models. Coregistered micro-CT with small-animal PET along with biopsies further confirmed the presence of tumor lesions in the mouse lungs.(18)F-FBZA specifically targets primary and metastatic melanotic melanoma lesions with high tumor uptake and may have translational potential.

    View details for DOI 10.2967/jnumed.109.066175

    View details for Web of Science ID 000272553600023

    View details for PubMedID 19759116

  • A 2-Helix Small Protein Labeled with Ga-68 for PET Imaging of HER2 Expression JOURNAL OF NUCLEAR MEDICINE Ren, G., Zhang, R., Liu, Z., Webster, J. M., Miao, Z., Gambhir, S. S., Syud, F. A., Cheng, Z. 2009; 50 (9): 1492-1499


    Affibody molecules are a class of scaffold proteins being developed into a generalizable approach to targeting tumors. Many 3-helix-based Affibody proteins have shown excellent in vivo properties for tumor imaging and therapy. By truncating one alpha-helix that is not responsible for receptor recognition in the Affibody and maturating the protein affinity through synthetic strategies, we have successfully identified in our previous research several small 2-helix proteins with excellent binding affinities to human epidermal growth factor receptor type 2 (HER2). With preferential properties such as faster blood clearance and tumor accumulation, lower immunogenic potential, and facile and economically viable synthetic schemes, we hypothesized that these 2-helix protein binders could become excellent molecular imaging probes for monitoring HER2 expression and modulation.In this study, a 2-helix small protein, MUT-DS, was chemically modified with a metal chelator, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA). DOTA-MUT-DS was then site-specifically radiolabeled with an important PET radionuclide, (68)Ga. The resulting radiolabeled anti-HER2 2-helix molecule was further evaluated as a potential molecular probe for small-animal PET HER2 imaging in a SKOV3 tumor mouse model.The 2-helix DOTA-MUT-DS showed high HER2-binding affinity (dissociation constant, 4.76 nM). The radiolabeled probe displayed high stability in mouse serum and specificity toward HER2 in cell cultures. Biodistribution and small-animal PET studies further showed that (68)Ga-DOTA-MUT-DS had rapid and high SKOV3 tumor accumulation and quick clearance from normal organs. The specificity of (68)Ga-DOTA-MUT-DS for SKOV3 tumors was confirmed by monitoring modulation of HER2 protein on treatment of tumor mice with heat shock protein 90 inhibitor 17-N,N-dimethyl ethylene diamine-geldanamycin in vivo.This proof-of-concept research clearly demonstrated that synthetic 2-helix (68)Ga-DOTA-MUT-DS is a promising PET probe for imaging HER2 expression in vivo. The Affibody-derived small 2-helix protein scaffold has great potential for developing targeting agents for a variety of tumor-associated biomarkers.

    View details for DOI 10.2967/jnumed.109.064287

    View details for Web of Science ID 000272548900023

    View details for PubMedID 19690041

  • Visualizing Implanted Tumors in Mice with Magnetic Resonance Imaging Using Magnetotactic Bacteria CLINICAL CANCER RESEARCH Benoit, M. R., Mayer, D., Barak, Y., Chen, I. Y., Hu, W., Cheng, Z., Wang, S. X., Spielman, D. M., Gambhir, S. S., Matin, A. 2009; 15 (16): 5170-5177


    To determine if magnetotactic bacteria can target tumors in mice and provide positive contrast for visualization using magnetic resonance imaging.The ability of the magnetotactic bacterium, Magnetospirillum magneticum AMB-1 (referred to from here as AMB-1), to confer positive magnetic resonance imaging contrast was determined in vitro and in vivo. For the latter studies, AMB-1 were injected either i.t. or i.v. Bacterial growth conditions were manipulated to produce small (approximately 25-nm diameter) magnetite particles, which were observed using transmission electron microscopy. Tumor targeting was confirmed using 64Cu-labeled bacteria and positron emission tomography and by determination of viable cell counts recovered from different organs and the tumor.We show that AMB-1 bacteria with small magnetite particles generate T1-weighted positive contrast, enhancing in vivo visualization by magnetic resonance imaging. Following i.v. injection of 64Cu-labeled AMB-1, positron emission tomography imaging revealed increasing colonization of tumors and decreasing infection of organs after 4 hours. Viable cell counts showed that, by day 6, the bacteria had colonized tumors but were cleared completely from other organs. Magnetic resonance imaging showed a 1.22-fold (P = 0.003) increased positive contrast in tumors on day 2 and a 1.39-fold increase (P = 0.0007) on day 6.Magnetotactic bacteria can produce positive magnetic resonance imaging contrast and colonize mouse tumor xenografts, providing a potential tool for improved magnetic resonance imaging visualization in preclinical and translational studies to track cancer.

    View details for DOI 10.1158/1078-0432.CCR-08-3206

    View details for Web of Science ID 000269024900019

    View details for PubMedID 19671860

    View details for PubMedCentralID PMC3409839

  • Engineered Two-Helix Small Proteins for Molecular Recognition CHEMBIOCHEM Webster, J. M., Zhang, R., Gambhir, S. S., Cheng, Z., Syud, F. A. 2009; 10 (8): 1293-1296


    Less is more: By starting with a high-affinity HER2-binding 3-helix affibody molecule, we successfully developed 2-helix small protein binders with 5 nM affinities by using a combination of several different strategies. Our efforts clearly suggest that 2-helix small proteins against important tumor targets can be obtained by rational protein design and engineering.

    View details for DOI 10.1002/cbic.200900062

    View details for Web of Science ID 000266561500003

    View details for PubMedID 19422008

  • Engineered Knottin Peptides: A New Class of Agents for Imaging Integrin Expression in Living Subjects CANCER RESEARCH Kimura, R. H., Cheng, Z., Gambhir, S. S., Cochran, J. R. 2009; 69 (6): 2435-2442


    There is a critical need for molecular imaging agents to detect cell surface integrin receptors that are present in human cancers. Previously, we used directed evolution to engineer knottin peptides that bind with high affinity ( approximately 10 to 30 nmol/L) to integrin receptors that are overexpressed on the surface of tumor cells and the tumor neovasculature. To evaluate these peptides as molecular imaging agents, we site-specifically conjugated Cy5.5 or (64)Cu-1,4,7,10-tetra-azacyclododecane-N,N',N'',N'''-tetraacetic acid (DOTA) to their N termini, and used optical and positron emission tomography (PET) imaging to measure their uptake and biodistribution in U87MG glioblastoma murine xenograft models. NIR fluorescence and microPET imaging both showed that integrin binding affinity plays a strong role in the tumor uptake of knottin peptides. Tumor uptake at 1 hour postinjection for two high-affinity (IC(50), approximately 20 nmol/L) (64)Cu-DOTA-conjugated knottin peptides was 4.47% +/- 1.21% and 4.56% +/- 0.64% injected dose/gram (%ID/g), compared with a low-affinity knottin peptide (IC(50), approximately 0.4 mumol/L; 1.48 +/- 0.53%ID/g) and c(RGDyK) (IC(50), approximately 1 mumol/L; 2.32 +/- 0.55%ID/g), a low-affinity cyclic pentapeptide under clinical development. Furthermore, (64)Cu-DOTA-conjugated knottin peptides generated lower levels of nonspecific liver uptake ( approximately 2%ID/g) compared with c(RGDyK) ( approximately 4%ID/g) 1 hour postinjection. MicroPET imaging results were confirmed by in vivo biodistribution studies. (64)Cu-DOTA-conjugated knottin peptides were stable in mouse serum, and in vivo metabolite analysis showed minimal degradation in the blood or tumor upon injection. Thus, engineered integrin-binding knottin peptides show great potential as clinical diagnostics for a variety of cancers.

    View details for DOI 10.1158/0008-5472.CAN-08-2495

    View details for Web of Science ID 000264541300037

    View details for PubMedID 19276378

    View details for PubMedCentralID PMC2833353

  • A Novel Method for Direct Site-Specific Radiolabeling of Peptides Using [F-18]FDG BIOCONJUGATE CHEMISTRY Namavari, M., Cheng, Z., Zhang, R., De, A., Levi, J., Hoerner, J. K., Yaghoubi, S. S., Syud, F. A., Gambhir, S. S. 2009; 20 (3): 432-436


    We have used the well-accepted and easily available 2-[(18)F]fluoro-2-deoxyglucose ([(18)F]FDG) positron emission tomography (PET) tracer as a prosthetic group for synthesis of (18)F-labeled peptides. We herein report the synthesis of [(18)F]FDG-RGD ((18)F labeled linear RGD) and [(18)F]FDG-cyclo(RGD(D)YK) ((18)F labeled cyclic RGD) as examples of the use of [(18)F]FDG. We have successfully prepared [(18)F]FDG-RGD and [(18)F]FDG-cyclo(RGD(D)YK) in 27.5% and 41% radiochemical yields (decay corrected) respectively. The receptor binding affinity study of FDG-cyclo(RGD(D)YK) for integrin alpha(v)beta(3), using alpha(v)beta(3) positive U87MG cells confirmed a competitive displacement with (125)I-echistatin as a radioligand. The IC(50) value for FDG-cyclo(RGD(D)YK) was determined to be 0.67 +/- 0.19 muM. High-contrast small animal PET images with relatively moderate tumor uptake were observed for [(18)F]FDG-RGD and [(18)F]FDG-cyclo(RGD(D)YK) as PET probes in xenograft models expressing alpha(v)beta(3) integrin. In conclusion, we have successfully used [(18)F]FDG as a prosthetic group to prepare (18)F]FDG-RGD and [(18)F]FDG-cyclic[RGD(D)YK] based on a simple one-step radiosynthesis. The one-step radiosynthesis methodology consists of chemoselective oxime formation between an aminooxy-functionalized peptide and [(18)F]FDG. The results have implications for radiolabeling of other macromolecules and would lead to a very simple strategy for routine preclinical and clinical use.

    View details for DOI 10.1021/bc800422b

    View details for Web of Science ID 000264389800005

    View details for PubMedID 19226160

    View details for PubMedCentralID PMC2765576

  • 123I labeled metaiodobenzylguanidine for diagnosis of neuroendocrine tumors Reports in Medical Imaging Jiang L, S. L. 2009; 2: 79-89
  • Photoactivatable caged bioluminescent probes for luciferase activity measurement. Chem Commun Shao Q, Jiang T, Ren G, Cheng Z*, Xing B*. 2009; 15: 4028-30
  • Photoacoustic Molecular Imaging using Single Walled Carbon Nanotubes in Living Mice Conference on Photons Plus Ultrasound - Imaging and Sensing 2009 de la Zerda, A., Zavaleta, C., Keren, S., Vaithilingam, S., Bodapati, S., Teed, R., Liu, Z., Levi, J., Smith, B. R., Ma, T., Oralkan, O., Cheng, Z., Chen, X., Dai, H., Khuri-Yakub, B. T., Gambhir, S. S. SPIE-INT SOC OPTICAL ENGINEERING. 2009

    View details for DOI 10.1117/12.806497

    View details for Web of Science ID 000285714100066

  • Particle Size, Surface Coating, and PEGylation Influence the Biodistribution of Quantum Dots in Living Mice SMALL Schipper, M. L., Iyer, G., Koh, A. L., Cheng, Z., Ebenstein, Y., Aharoni, A., Keren, S., Bentolila, L. A., Li, J., Rao, J., Chen, X., Banin, U., Wu, A. M., Sinclair, R., Weiss, S., Gambhir, S. S. 2009; 5 (1): 126-134


    This study evaluates the influence of particle size, PEGylation, and surface coating on the quantitative biodistribution of near-infrared-emitting quantum dots (QDs) in mice. Polymer- or peptide-coated 64Cu-labeled QDs 2 or 12 nm in diameter, with or without polyethylene glycol (PEG) of molecular weight 2000, are studied by serial micropositron emission tomography imaging and region-of-interest analysis, as well as transmission electron microscopy and inductively coupled plasma mass spectrometry. PEGylation and peptide coating slow QD uptake into the organs of the reticuloendothelial system (RES), liver and spleen, by a factor of 6-9 and 2-3, respectively. Small particles are in part renally excreted. Peptide-coated particles are cleared from liver faster than physical decay alone would suggest. Renal excretion of small QDs and slowing of RES clearance by PEGylation or peptide surface coating are encouraging steps toward the use of modified QDs for imaging living subjects.

    View details for DOI 10.1002/smll.200800003

    View details for Web of Science ID 000262895300019

    View details for PubMedID 19051182

    View details for PubMedCentralID PMC3084659

  • Targeted microbubbles for imaging tumor angiogenesis: Assessment of whole-body biodistribution with dynamic micro-PET in mice RADIOLOGY Willmann, J. K., Cheng, Z., Davis, C., Lutz, A. M., Schipper, M. L., Nielsen, C. H., Gambhir, S. S. 2008; 249 (1): 212-219


    To evaluate in vivo whole-body biodistribution of microbubbles (MBs) targeted to tumor angiogenesis-related vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) by using dynamic micro-positron emission tomography (PET) in living mice.Animal protocols were approved by the Institutional Administrative Panel on Laboratory Animal Care. Lipid-shell perfluorocarbon-filled MBs, targeted to VEGFR2 via anti-VEGFR2 antibodies, were radiolabeled by conjugating the radiofluorination agent N-succinimidyl-4-[(18)F]fluorobenzoate (SFB) to the anti-VEGFR2 antibodies. These MBs were then injected intravenously into nude mice (n = 4) bearing angiosarcomas, and the whole-body biodistribution of these probes was assessed for 60 minutes by using dynamic micro-PET. Results were compared with ex vivo gamma counting (n = 6) and immunofluorescence staining (n = 6). Control studies in angiosarcoma-bearing mice were performed with injection of the radiolabeled antibodies alone (n = 3) or free SFB (n = 3). A mixed-effects regression of MB accumulation on fixed effects of time and tissue type (tumor or muscle) and random effect of animal was performed.VEGFR2-targeted MBs rapidly cleared from the blood circulation (50% blood clearance after approximately 3.5 minutes) and accumulated in the liver (mean, 33.4% injected dose [ID]/g +/- 13.7 [standard deviation] at 60 minutes) and spleen (mean, 9.3% ID/g +/- 6.5 at 60 minutes) on the basis of micro-PET imaging. These findings were confirmed with ex vivo gamma counting. Uptake of targeted MBs was significantly higher (P < .0001) in tumor than in adjacent skeletal muscle tissue. Immunofluorescence staining demonstrated accumulation of the targeted MBs within hepatic Kupffer cells and splenic macrophages. Biodistribution of the radiolabeled antibodies and free SFB differed from the distribution of the targeted MBs.Dynamic micro-PET allows assessment of in vivo biodistribution of VEGFR2-targeted MBs.

    View details for DOI 10.1148/radiol.2491072050

    View details for Web of Science ID 000259505200025

    View details for PubMedID 18695212

    View details for PubMedCentralID PMC2657857

  • Noninvasive Raman spectroscopy in living mice for evaluation of tumor targeting with carbon nanotubes NANO LETTERS Zavaleta, C., de la Zerda, A., Liu, Z., Keren, S., Cheng, Z., Schipper, M., Chen, X., Dai, H., Gambhir, S. S. 2008; 8 (9): 2800-2805


    An optimized noninvasive Raman microscope was used to evaluate tumor targeting and localization of single walled carbon nanotubes (SWNTs) in mice. Raman images were acquired in two groups of tumor-bearing mice. The control group received plain-SWNTs, whereas the experimental group received tumor targeting RGD-SWNTs intravenously. Raman imaging commenced over the next 72 h and revealed increased accumulation of RGD-SWNTs in tumor ( p < 0.05) as opposed to plain-SWNTs. These results support the development of a new preclinical Raman imager.

    View details for DOI 10.1021/nl801362a

    View details for Web of Science ID 000259140200034

    View details for PubMedID 18683988

    View details for PubMedCentralID PMC2910584

  • Carbon nanotubes as photoacoustic molecular imaging agents in living mice NATURE NANOTECHNOLOGY de la Zerda, A., Zavaleta, C., Keren, S., Vaithilingam, S., Bodapati, S., Liu, Z., Levi, J., Smith, B. R., Ma, T., Oralkan, O., Cheng, Z., Chen, X., Dai, H., Khuri-Yakub, B. T., Gambhir, S. S. 2008; 3 (9): 557-562


    Photoacoustic imaging of living subjects offers higher spatial resolution and allows deeper tissues to be imaged compared with most optical imaging techniques. As many diseases do not exhibit a natural photoacoustic contrast, especially in their early stages, it is necessary to administer a photoacoustic contrast agent. A number of contrast agents for photoacoustic imaging have been suggested previously, but most were not shown to target a diseased site in living subjects. Here we show that single-walled carbon nanotubes conjugated with cyclic Arg-Gly-Asp (RGD) peptides can be used as a contrast agent for photoacoustic imaging of tumours. Intravenous administration of these targeted nanotubes to mice bearing tumours showed eight times greater photoacoustic signal in the tumour than mice injected with non-targeted nanotubes. These results were verified ex vivo using Raman microscopy. Photoacoustic imaging of targeted single-walled carbon nanotubes may contribute to non-invasive cancer imaging and monitoring of nanotherapeutics in living subjects.

    View details for DOI 10.1038/nnano.2008.231

    View details for Web of Science ID 000259013100014

    View details for PubMedID 18772918

    View details for PubMedCentralID PMC2562547

  • Real-time intravital imaging of RGD-quantum dot binding to luminal endothelium in mouse tumor neovasculature NANO LETTERS Smith, B. R., Cheng, Z., De, A., Koh, A. L., Sinclair, R., Gambhir, S. S. 2008; 8 (9): 2599-2606


    Nanoscale materials have increasingly become subject to intense investigation for use in cancer diagnosis and therapy. However, there is a fundamental dearth in cellular-level understanding of how nanoparticles interact within the tumor environment in living subjects. Adopting quantum dots (qdots) for their excellent brightness, photostability, monodispersity, and fluorescent yield, we link arginine-glycine-aspartic acid (RGD) peptides to target qdots specifically to newly formed/forming blood vessels expressing alpha vbeta 3 integrins. Using this model nanoparticle system, we exploit intravital microscopy with subcellular ( approximately 0.5 microm) resolution to directly observe and record, for the first time, the binding of nanoparticle conjugates to tumor blood vessels in living subjects. This generalizable method enabled us to show that in this model qdots do not extravasate and, unexpectedly, that they only bind as aggregates rather than individually. This level of understanding is critical on the path toward ensuring regulatory approval of nanoparticles in humans for disease diagnostics and therapeutics. Equally vital, the work provides a platform by which to design and optimize molecularly targeted nanoparticles including quantum dots for applications in living subjects.

    View details for DOI 10.1021/nl80141f

    View details for Web of Science ID 000259140200001

    View details for PubMedID 18386933

  • Direct site-specific radiolabeling of an Affibody protein with 4-[18F]fluorobenzaldehyde via oxime chemistry. Molecular imaging and biology Namavari, M., Padilla De Jesus, O., Cheng, Z., De, A., Kovacs, E., Levi, J., Zhang, R., Hoerner, J. K., Grade, H., Syud, F. A., Gambhir, S. S. 2008; 10 (4): 177-181


    In this study, we introduce a methodology for preparing 18F-labeled Affibody protein, specifically 18F-Anti-HER2 dimeric Affibody (14 kDa), for in vivo imaging of HER2neu with positron emission tomography (PET).We have used 4-[18F]fluorobenzaldehyde as a synthon to prepare 18F-Anti-HER2 Affibody. Aminooxy-functionalized Affibody (Anti-HER2-ONH2) was incubated with 4-[18F]fluorobenzaldehyde in ammonium acetate buffer at pH 4 in the presence of methanol at 70 degrees C for 15 min. The resulting 18F-labeled Affibody molecule was evaluated as a PET probe in xenograft models expressing HER2.We have successfully prepared 18F-Anti-HER2 dimeric Affibody (14 kDa), N-(4-[18F]fluorobenzylidine)oxime-Anti-HER2 Affibody, [18F]FBO-Anti-HER2, in 26-30% radiochemical yields (decay corrected). High-contrast small-animal PET images with relatively moderate tumor uptake (1.79 +/- 0.40% ID/g) were observed for the 18F-Anti-HER2 Affibody.Site-specific 18F-labeled Affibody against HER2 has been synthesized via chemoselective oxime formation between an aminooxy-functionalized Affibody and 18F-fluorobenzaldehyde. The results have implications for radiolabeling of other affibodies and macromolecules and should also be important for advancing Affibody imaging with PET.

    View details for DOI 10.1007/s11307-008-0142-7

    View details for PubMedID 18481153

  • Small-animal PET Imaging of human epidermal growth factor receptor type 2 expression with site-specific F-18-labeled protein scaffold molecules JOURNAL OF NUCLEAR MEDICINE Cheng, Z., De Jesus, O. P., Namavari, M., De, A., Levi, J., Webster, J. M., Zhang, R., Lee, B., Syud, F. A., Gambhir, S. S. 2008; 49 (5): 804-813


    Human epidermal growth factor receptor type 2 (HER2) is a well-established tumor biomarker that is overexpressed in a wide variety of cancers and that serves as a molecular target for therapeutic intervention. HER2 also serves as a prognostic indicator of patient survival and as a predictive marker of the response to antineoplastic therapy. The development of (18)F-labeled biomolecules for PET imaging of HER2 (HER2 PET) is very important because it may provide a powerful tool for the early detection of HER2-positive tumor recurrence and for the monitoring of HER2-based tumor treatment.In this study, anti-HER2 monomeric and dimeric protein scaffold molecules [Z(HER2:477) and (Z(HER2:477))(2), respectively] were radiofluorinated at a reasonable radiochemical yield (13%-18%) by use of site-specific oxime chemistry. The resulting radiofluorinated protein scaffold molecules were then evaluated as potential molecular probes for small-animal HER2 PET by use of a SKOV3 tumor-bearing mouse model.The 4-(18)F-fluorobenzaldehyde conjugated aminooxy-protein scaffolds [(18)F-N-(4-fluorobenzylidene)oxime (FBO)-Z(HER2:477) and (18)F-FBO-(Z(HER2:477))(2)] both displayed specific HER2-binding ability in vitro. Biodistribution and small-animal PET imaging studies further revealed that (18)F-FBO-Z(HER2:477) showed rapid and high SKOV3 tumor accumulation and quick clearance from normal tissues, whereas (18)F-FBO-(Z(HER2:477))(2) showed poor in vivo performance (low tumor uptake and tumor-to-normal tissue ratios). The specificity of (18)F-FBO-Z(HER2:477) for SKOV3 tumors was confirmed by its lower uptake on pretreatment of tumor-bearing mice with the HER2-targeting agents Z(HER2) and trastuzumab. Moreover, small-animal PET imaging studies revealed that (18)F-FBO-Z(HER2:477) produced higher-quality tumor imaging than (18)F-FBO-(Z(HER2:477))(2). (18)F-FBO-Z(HER2:477) could clearly identify HER2-positive tumors with good contrast.Overall, these data demonstrate that (18)F-FBO-Z(HER2:477) is a promising PET probe for imaging HER2 expression in living mice. It has a high potential for translation to clinical applications. The radiofluorination method developed can also be used as a general strategy for the site-specific labeling of other proteins with (18)F. The protein scaffold molecules used here are attractive for the further development of PET probes for other molecular targets.

    View details for DOI 10.2967/jnumed.107.047381

    View details for Web of Science ID 000255809100032

    View details for PubMedID 18413392

  • Noninvasive molecular imaging of small living subjects using Raman spectroscopy PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Keren, S., Zavaleta, C., Cheng, Z., de la Zerda, A., Gheysens, O., Gambhir, S. S. 2008; 105 (15): 5844-5849


    Molecular imaging of living subjects continues to rapidly evolve with bioluminescence and fluorescence strategies, in particular being frequently used for small-animal models. This article presents noninvasive deep-tissue molecular images in a living subject with the use of Raman spectroscopy. We describe a strategy for small-animal optical imaging based on Raman spectroscopy and Raman nanoparticles. Surface-enhanced Raman scattering nanoparticles and single-wall carbon nanotubes were used to demonstrate whole-body Raman imaging, nanoparticle pharmacokinetics, multiplexing, and in vivo tumor targeting, using an imaging system adapted for small-animal Raman imaging. The imaging modality reported here holds significant potential as a strategy for biomedical imaging of living subjects.

    View details for DOI 10.1073/pnas.0710575105

    View details for Web of Science ID 000255237200036

    View details for PubMedID 18378895

    View details for PubMedCentralID PMC2299220

  • The Application of Cleavable Linker in Development of Molecular Probe for Cancer Molecular Imaging. Recent Advances of Bioconjugate Chemistry in Molecular Imaging, Cheng Z, Levi J. 2008: 53-70
  • Bisdeoxycoelenterazine derivatives for improvement of bioluminescence resonance energy transfer assays JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Levi, J., De, A., Cheng, Z., Gambhir, S. S. 2007; 129 (39): 11900-?

    View details for DOI 10.1021/ja073936h

    View details for Web of Science ID 000249887700013

    View details for PubMedID 17850082

  • MicroPET-based biodistribution of quantum dots in living mice JOURNAL OF NUCLEAR MEDICINE Schipper, M. L., Cheng, Z., Lee, S., Bentolila, L. A., Iyer, G., Rao, J., Chen, X., Wu, A. M., Weiss, S., Gambhir, S. S. 2007; 48 (9): 1511-1518


    This study evaluates the quantitative biodistribution of commercially available CdSe quantum dots (QD) in mice.(64)Cu-Labeled 800- or 525-nm emission wavelength QD (21- or 12-nm diameter), with or without 2,000 MW (molecular weight) polyethylene glycol (PEG), were injected intravenously into mice (5.55 MBq/25 pmol QD) and studied using well counting or by serial microPET and region-of-interest analysis.Both methods show rapid uptake by the liver (27.4-38.9 %ID/g) (%ID/g is percentage injected dose per gram tissue) and spleen (8.0-12.4 %ID/g). Size has no influence on biodistribution within the range tested here. Pegylated QD have slightly slower uptake into liver and spleen (6 vs. 2 min) and show additional low-level bone uptake (6.5-6.9 %ID/g). No evidence of clearance from these organs was observed.Rapid reticuloendothelial system clearance of QD will require modification of QD for optimal utility in imaging living subjects. Formal quantitative biodistribution/imaging studies will be helpful in studying many types of nanoparticles, including quantum dots.

    View details for DOI 10.2967/jnumed.107.040071

    View details for PubMedID 17704240

  • Small-animal PET of melanocortin 1 receptor expression using a F-18-labeled alpha-melanocyte-stimulating hormone analog JOURNAL OF NUCLEAR MEDICINE Cheng, Z., Zhang, L., Graves, E., Xiong, Z., Dandekar, M., Chen, X., Gambhir, S. S. 2007; 48 (6): 987-994


    (18)F-Labeled small synthetic peptides have emerged as attractive probes for imaging various molecular targets with PET. The alpha-melanocyte-stimulating hormone (alpha-MSH) receptor (melanocortin type 1 receptor [MC1R]) is overexpressed in most murine and human melanomas. It is a promising molecular target for diagnosis and therapy of melanomas. However, (18)F compounds have not been successfully developed for imaging the MC1R.In this study, an alpha-MSH analog, Ac-Nle-Asp-His-D-Phe-Arg-Trp-Gly-Lys-NH(2) (NAPamide), was radiolabeled with N-succinimidyl-4-(18)F-fluorobenzoate ((18)F-SFB). The resulting radiopeptide was evaluated as a potential molecular probe for small-animal PET of melanoma and MC1R expression in melanoma xenografted mouse models.The binding affinity of (19)F-SFB-conjugated NAPamide, (19)F-FB-NAPamide, was determined to be 7.2 +/- 1.2 nM (mean +/- SD) using B16/F10 cells and (125)I-(Tyr(2))-[Nle(4),D-Phe(7)]-alpha-MSH [(125)I-(Tyr(2))-NDP] as a radioligand. The biodistribution of (18)F-FB-NAPamide was then investigated in C57BL/6 mice bearing subcutaneous murine B16/F10 melanoma tumors with high expression of MC1Rs and Fox Chase Scid mice bearing human A375M melanoma with a relatively low number of MC1R receptors. Biodistribution experiments showed that tumor uptake values (percentage injected dose per gram of tumor [%ID/g]) of (18)F-FB-NAPamide were 1.19 +/- 0.11 %ID/g and 0.46 +/- 0.11 %ID/g, in B16/F10 and A375M xenografted melanoma at 1 h after injection, respectively. Furthermore, the B16/F10 tumor uptake was significantly inhibited by coinjection with excess alpha-MSH peptide (P < 0.05), indicating that (18)F-FB-NAPamide specifically recognizes the MC1R in living mice. Small-animal PET of (18)F-FB-NAPamide in mice bearing B16/F10 and A375M tumors at 1 h after tail vein injection revealed good B16/F10 tumor-to-background contrast and low A375M tumor-to-background ratios.(18)F-FB-NAPamide is a promising molecular probe for alpha-MSH receptor-positive melanoma PET and warrants further study.

    View details for DOI 10.2967/jnumed.107.039602

    View details for Web of Science ID 000247054800024

    View details for PubMedID 17504880

  • Fluorescent fructose derivatives for imaging breast cancer cells BIOCONJUGATE CHEMISTRY Levi, J., Cheng, Z., Gheysens, O., Patel, M., Chan, C. T., Wang, Y., Namavari, M., Gambhir, S. S. 2007; 18 (3): 628-634


    Breast cancer cells are known to overexpress Glut5, a sugar transporter responsible for the transfer of fructose across the cell membrane. Since Glut5 transporter is not significantly expressed in normal breast cells, fructose uptake can potentially be used to differentiate between normal and cancerous cells. Fructose was labeled with two fluorophores at the C-1 position: 7-nitro-1,2,3-benzadiazole (NBD) and Cy5.5. The labeling site was chosen on the basis of the presence and substrate specificity of the key proteins involved in the first steps of fructose metabolism. Using fluorescence microscopy, the uptake of the probes was studied in three breast cancer cell lines: MCF 7, MDA-MB-435, and MDA-MB-231. Both fluorescent fructose derivatives showed a very good uptake in all tested cell lines. The level of uptake was comparable to that of the corresponding glucose analogs, 2-NBDG and Cy5.5-DG. Significant uptake of 1-NBDF derivative was not observed in cells lacking Glut5 transporter, while the uptake of the 1-Cy5.5-DF derivative was independent of the presence of a fructose-specific transporter. While 1-NBDF showed Glut5-specific accumulation, the coupling of a large fluorophore such as Cy5.5 likely introduces big structural and electronic changes, leading to a fructose derivative that does not accurately describe the uptake of fructose in cells.

    View details for DOI 10.1021/bc060184s

    View details for Web of Science ID 000246485500005

    View details for PubMedID 17444608

    View details for PubMedCentralID PMC4145876

  • Cu-64-Labeled alpha-melanocyte-stimulating hormone analog for MicroPET imaging of melanocortin 1 receptor expression BIOCONJUGATE CHEMISTRY Cheng, Z., Xiong, Z., Subbarayan, M., Chen, X., Gambhir, S. S. 2007; 18 (3): 765-772


    The alpha-melanocyte-stimulating hormone (alpha-MSH) receptor (melanocortin type 1 receptor, or MC1R) plays an important role in the development and growth of melanoma cells. It was found that MC1R was overexpressed on most murine and human melanoma, making it a promising molecular target for melanoma imaging and therapy. Radiolabeled alpha-MSH peptide and its analogs that can specifically bind with MC1R have been extensively explored for developing novel agents for melanoma detection and radionuclide therapy. The goal of this study was to evaluate a 64Cu-labeled alpha-MSH analog, Ac-Nle-Asp-His-D-Phe-Arg-Trp-Gly-Lys(DOTA)-NH2 (DOTA-NAPamide), as a potential molecular probe for microPET imaging of melanoma and MC1R expression in melanoma xenografted mouse models. 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) conjugated NAPamide was synthesized and radiolabeled with 64Cu (t1/2=12 h) in NH4OAc (0.1 M; pH 5.5) buffered solution for 60 min at 50 degrees C. Cell culture studies reveal rapid and high uptake and internalization of 64Cu-DOTA-NAPamide in B16F10 cells. Over 90% of receptor-bound tracer is internalized at 3 h incubation. A cellular retention study demonstrates that the receptor-bound 64Cu-DOTA-NAPamide is slowly released from the B16F10 cells into the medium; 66% of the radioactivity is still associated with the cells even after 3 h incubation. The biodistribution of 64Cu-DOTA-NAPamide was then investigated in C57BL/6 mice bearing subcutaneous murine B16F10 melanoma tumors with high capacity of MC1R and Fox Chase Scid mice bearing human A375M melanoma with a relatively low number of MC1R receptors. Tumor uptake values of 64Cu-DOTA-NAPamide are found to be 4.63 +/- 0.45% and 2.49 +/- 0.31% ID/g in B16F10 and A375M xenografted melanoma at 2 h postinjection (pi), respectively. The B16F10 tumor uptake at 2 h pi is further inhibited to 2.29 +/- 0.24% ID/g, while A375M tumor uptake at 2 h pi remains 2.20 +/- 0.41% ID/g with a coinjection of excess alpha-MSH peptide. MicroPET imaging of 64Cu-DOTA-NAPamide in B16F10 tumor mice clearly shows good tumor localization. However, low A375M tumor uptake and poor tumor to normal tissue contrast were observed. This study demonstrates that 64Cu-DOTA-NAPamide is a promising molecular probe for alpha-MSH receptor positive melanoma PET imaging as well as MC1R expression imaging in living mice.

    View details for DOI 10.1021/bc060306g

    View details for Web of Science ID 000246485500021

    View details for PubMedID 17348700

  • In vivo bioluminescence tumor imaging of RGD peptide-modified adenoviral vector encoding firefly luciferase reporter gene MOLECULAR IMAGING AND BIOLOGY Niu, G., Xiong, Z., Cheng, Z., Cai, W., Gambhir, S. S., Xing, L., Chen, X. 2007; 9 (3): 126-134


    The goal of this study is to demonstrate the feasibility of chemically modified human adenovirus (Ad) vectors for tumor retargeting.E1- and E3-deleted Ad vectors carrying firefly luciferase reporter gene under cytomegalovirus promoter (AdLuc) was surface-modified with cyclic arginine-glycine-aspartic acid (RGD) peptides through a bifunctional poly(ethyleneglycol) linker (RGD-PEG-AdLuc) for integrin alpha(v)beta(3) specific delivery. The Coxsackie and adenovirus viral receptor (CAR) and integrin alpha(v)beta(3) expression in various tumor cell lines was determined by reverse transcriptase PCR and fluorescence-activated cell sorting. Bioluminescence imaging was performed in vitro and in vivo to evaluate RGD-modified AdLuc infectivity.RGD-PEG-AdLuc abrogated the native CAR tropism and exhibited significantly enhanced transduction efficiency of integrin-positive tumors than AdLuc through intravenous administration.This approach provides a robust platform for site-specific gene delivery and noninvasive monitoring of the transgene delivery efficacy and homing.

    View details for DOI 10.1007/s11307-007-0079-2

    View details for Web of Science ID 000246175500005

    View details for PubMedID 17297551

    View details for PubMedCentralID PMC4165526

  • Near-infrared fluorescent deoxyglucose analogue for tumor optical imaging in cell culture and living mice BIOCONJUGATE CHEMISTRY Cheng, Z., Levi, J., Xiong, Z., Gheysens, O., Keren, S., Chen, X., Gambhir, S. S. 2006; 17 (3): 662-669


    2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) has extensively been used for clinical diagnosis, staging, and therapy monitoring of cancer and other diseases. Nonradioactive glucose analogues enabling the screening of the glucose metabolic rate of tumors are of particular interest for anticancer drug development. A nonradioactive fluorescent deoxyglucose analogue may have many applications for both imaging of tumors and monitoring therapeutic efficacy of drugs in living animals and may eventually translate to clinical applications. We found that a fluorescent 2-deoxyglucose analogue, 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NBDG), can be delivered in several tumor cells via the glucose transporters (GLUTs). We therefore conjugated D-glucosamine with a near-infrared (NIR) fluorphor Cy5.5 and tested the feasibility of the Cy5.5-D-glucosamine (Cy5.5-2DG) conjugate for NIR fluorescence imaging of tumors in a preclinical xenograft animal model. Cy5.5-2DG was prepared by conjugating Cy5.5 monofunctional N-hydroxysuccinimide ester (Cy5.5-NHS) and D-glucosamine followed by high-performance liquid chromatography purification. The accumulation of Cy5.5-2DG and Cy5.5-NHS in different tumor cell lines at 37 and 4 degrees C were imaged using a fluorescence microscope. Tumor targeting and retention of Cy5.5-2DG and Cy5.5-NHS in a subcutaneous U87MG glioma and A375M melanoma tumor model were evaluated and quantified by a Xenogen IVIS 200 optical cooled charged-coupled device system. Fluorescence microscopy imaging shows that Cy5.5-2DG and Cy5.5-NHS are taken up and trapped by a variety of tumor cell lines at 37 degrees C incubation, while they exhibit marginal uptake at 4 degrees C. The tumor cell uptake of Cy5.5-2DG cannot be blocked by the 50 mM D-glucose, suggesting that Cy5.5-2DG may not be delivered in tumor cells by GLUTs. U87MG and A375M tumor localization was clearly visualized in living mice with both NIR fluorescent probes. Tumor/muscle contrast was clearly visible as early as 30 min postinjection (pi), and the highest U87MG tumor/muscle ratios of 2.81 +/- 0.10 and 3.34 +/- 0.23 were achieved 24 h pi for Cy5.5-2DG and Cy5.5-NHS, respectively. While as a comparison, the micropositron emission tomography imaging study shows that [18F]FDG preferentially localizes to the U87MG tumor, with resulting tumor/muscle ratios ranging from 3.89 to 4.08 after 30 min to 2 h postadministration of the probe. In conclusion, the NIR fluorescent glucose analogues, Cy5.5-2DG and Cy5.5-NHS, both demonstrate tumor-targeting abilities in cell culture and living mice. More studies are warranted to further explore their application for optical tumor imaging. To develop NIR glucose analogues with the ability to target GLUTs/hexokinase, it is highly important to select NIR dyes with a reasonable molecular size.

    View details for DOI 10.1021/bc050345c

    View details for Web of Science ID 000237576000013

    View details for PubMedID 16704203

    View details for PubMedCentralID PMC3191878

  • Imaging chemically modified adenovirus for targeting tumors expressing integrin alpha(v)beta(3) in living mice with mutant herpes simplex virus type 1 thymidine kinase PET reporter gene JOURNAL OF NUCLEAR MEDICINE Xiong, Z. M., Cheng, Z., Zhang, X. Z., Patel, M., Wu, J. C., Gambhir, S. S., Chen, X. Y. 2006; 47 (1): 130-139


    The aim of this study was to change adenovirus tropism by chemical modification of the fiber knobs with PEGylated RGD peptide for targeting integrin alpha(v)beta(3) that is uniquely or highly expressed in tumor cells and neovasculature of tumors of various origins.The first generation Ad (Ad) vector, which expresses the herpes simplex virus type 1 mutant thymidine kinase (HSV1-sr39tk) gene under the control of cytomegalovirus (CMV) promoter was conjugated with poly(ethylene glycol) (PEG) or RGD-PEG. The transduction efficiency of Ads (Adtk, PEG-Adtk, and RGD-PEG-Adtk) into different types of cells (293T, MCF7, MDA-MB-435, and U87MG) was analyzed and quantified by thymidine kinase (TK) assay using 8-(3)H-penciclovir (8-(3)H-PCV) as substrate. The in vivo infectivity of the Ad vectors after intravenous administration into integrin alpha(v)beta(3)-positive U87MG and MDA-MB-435 tumor-bearing athymic nude mice was measured by both noninvasive microPET using 9-[4-(18)F-fluoro-3-(hydroxymethyl)butyl]guanine ((18)F-FHBG) as a reporter probe and ex vivo TK assay of the tumor and tissue homogenates.PEGylation completely abrogated coxsackievirus and adenovirus receptor (CAR)-knob interaction and the infectivity of PEG-Adtk is significantly lower than that of unmodified Adtk in CAR-positive cells. RGD-PEG-modified virus (RGD-PEG-Adtk) had significantly higher infectivity than PEG-Adtk and the extent of increase is related to both CAR and integrin alpha(v)beta(3) expression levels. (18)F-FHBG had minimal nonspecific uptake in the liver and tumors that are void of sr39tk. Mice preinjected intravenously with unmodified Adtk resulted in high hepatic uptake and moderate tumor accumulation of the tracer. In contrast, RGD-PEG-Adtk administration resulted in significantly lower liver uptake without compromising the tumor accumulation of (18)F-FHBG. Expression of TK in the liver and tumor homogenates corroborated with the magnitude of (18)F-FHBG uptake quantified by noninvasive microPET. Analysis of liver and tumor tissue integrin level confirmed that RGD-integrin interaction is responsible for the enhanced tumor infectivity of RGD-PEG-Adtk.The results of this study suggest that RGD-PEG conjugation is an effective way to modify Ad vector tropism for improved systemic gene delivery. Noninvasive PET and (18)F-FHBG are able to monitor in vivo transfectivity of both Adtk and RGD-PEG-Adtk vectors in the liver and tumors after intravenous injection.

    View details for PubMedID 16391197

  • Reproducibility of 3 '-deoxy-3 '-F-18-fluorothymidine MicroPET studies in tumor xenografts in mice JOURNAL OF NUCLEAR MEDICINE Tseng, J. R., Dandekar, M., Subbarayan, M., Cheng, Z., Park, J. M., Louie, S., Gambhir, S. S. 2005; 46 (11): 1851-1857


    3'-Deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) has been used to image tumor proliferation in preclinical and clinical studies. Serial microPET studies may be useful for monitoring therapy response or for drug screening; however, the reproducibility of serial scans has not been determined. The purpose of this study was to determine the reproducibility of (18)F-FLT microPET studies.C6 rat glioma xenografts were implanted into nude mice (n = 9) and grown to mean diameters of 5-17 mm for approximately 2 wk. A 10-min acquisition was performed on a microPET scanner approximately 1 h after (18)F-FLT (1.9-7.4 MBq [50-200 muCi]) was injected via the tail vein. A second microPET scan was performed approximately 6 h later on the same day after reinjection of (18)F-FLT to assess for reproducibility. Most of the mice were studied twice within the same week (for a total of 17 studies). Images were analyzed by drawing an ellipsoidal region of interest (ROI) around the tumor xenograft activity. Percentage injected dose per gram (%ID/g) values were calculated from the mean activity in the ROIs. Coefficients of variation and differences in %ID/g values between studies from the same day were calculated to determine the reproducibility after subtraction of the estimated residual tumor activity from the first (18)F-FLT injection.The coefficient of variation (mean +/- SD) for %ID/g values between (18)F-FLT microPET scans performed 6 h apart on the same day was 14% +/- 10%. The difference in %ID/g values between scans was -0.06% +/- 1.3%. Serum thymidine levels were mildly correlated with %ID/g values (R(2) = 0.40). Tumor size, mouse body weight, injected dose, and fasting state did not contribute to the variability of the scans; however, consistent scanning parameters were necessary to ensure accurate studies, in particular, controlling body temperature, the time of imaging after injection, and the ROI size.(18)F-FLT microPET mouse tumor xenograft studies are reproducible with moderately low variability. Serial studies may be performed to assess for significant changes in therapy response or for preclinical drug development.

    View details for Web of Science ID 000233095800017

    View details for PubMedID 16269599

  • Near-infrared fluorescent RGD peptides for optical imaging of integrin alpha(v)beta 3 expression in living mice BIOCONJUGATE CHEMISTRY Cheng, Z., Wu, Y., Xiong, Z. M., Gambhir, S. S., Chen, X. Y. 2005; 16 (6): 1433-1441


    Near-infrared fluorescence optical imaging is a powerful technique for studying diseases at the molecular level in preclinical models. We recently reported that monomeric RGD peptide c(RGDyK) conjugated to the NIR fluorescent dye specifically targets integrin receptor both in cell culture and in living subjects. In this report, Cy5.5-conjugated mono-, di-, and tetrameric RGD peptides were evaluated in a subcutaneous U87MG glioblastoma xenograft model in order to investigate the effect of multimerization of RGD peptide on integrin avidity and tumor targeting efficacy. The binding affinities of Cy5.5-conjugated RGD monomer, dimer, and tetramer for alpha(v)beta(3) integrin expressed on U87MG cell surface were determined to be 42.9 +/- 1.2, 27.5 +/- 1.2, and 12.1 +/- 1.3 nmol/L, respectively. All three peptide-dye conjugates had integrin specific uptake both in vitro and in vivo. The subcutaneous U87MG tumor can be clearly visualized with each of these three fluorescent probes. Among them, tetramer displayed highest tumor uptake and tumor-to-normal tissue ratio from 0.5 to 4 h postinjection. Tumor-to-normal tissue ratio for Cy5.5-conjugated RGD monomer, dimer, and tetramer were found to be 3.18 +/- 0.16, 2.98 +/- 0.05, and 3.63 +/- 0.09, respectively, at 4 h postinjection. These results suggest that Cy5.5-conjugated monomeric, dimeric, and tetrameric RGD peptides are all suitable for integrin expression imaging. The multmerization of RGD peptide results in moderate improvement of imaging characteristics of the tetramer, compared to that of the monomer and dimeric counterparts.

    View details for DOI 10.1021/bc0501698

    View details for Web of Science ID 000233393800015

    View details for PubMedID 16287239

  • microPET imaging of glioma integrin alpha(V)beta(3) expression using Cu-64-labeled tetrameric RGD peptide JOURNAL OF NUCLEAR MEDICINE Wu, Y., Zhang, X. Z., Xiong, Z. M., Cheng, Z., Fisher, D. R., Liu, S., Gambhir, S. S., Chen, X. Y. 2005; 46 (10): 1707-1718


    Integrin alpha(v)beta(3) plays a critical role in tumor-induced angiogenesis and metastasis and has become a promising diagnostic indicator and therapeutic target for various solid tumors. Radiolabeled RGD peptides that are integrin specific can be used for noninvasive imaging of integrin expression level as well as for integrin-targeted radionuclide therapy.In this study we developed a tetrameric RGD peptide tracer (64)Cu-DOTA-E{E[c(RGDfK)](2)}(2) (DOTA is 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) for PET imaging of integrin alpha(v)beta(3) expression in female athymic nude mice bearing the subcutaneous UG87MG glioma xenografts.The RGD tetramer showed significantly higher integrin binding affinity than the corresponding monomeric and dimeric RGD analogs, most likely due to a polyvalency effect. The radiolabeled peptide showed rapid blood clearance (0.61 +/- 0.01 %ID/g at 30 min and 0.21 +/- 0.01 %ID/g at 4 h after injection, respectively [%ID/g is percentage injected dose per gram]) and predominantly renal excretion. Tumor uptake was rapid and high, and the tumor washout was slow (9.93 +/- 1.05 %ID/g at 30 min after injection and 4.56 +/- 0.51 %ID/g at 24 h after injection). The metabolic stability of (64)Cu-DOTA-E{E[c(RGDfK)](2)}(2) was determined in mouse blood, urine, and liver and kidney homogenates at different times after tracer injection. The average fractions of intact tracer in these organs at 1 h were approximately 70%, 58%, 51%, and 26%, respectively. Noninvasive microPET studies showed significant tumor uptake and good contrast in the subcutaneous tumor-bearing mice, which agreed well with the biodistribution results. Integrin alpha(v)beta(3) specificity was demonstrated by successful blocking of tumor uptake of (64)Cu-DOTA-E{E[c(RGDfK)](2)}(2) in the presence of excess c(RGDyK) at 1 h after injection. The highest absorbed radiation doses determined for the human reference adult were received by the urinary bladder wall (0.262 mGy/MBq), kidneys (0.0296 mGy/MBq), and liver (0.0242 mGy/MBq). The average effective dose resulting from a single (64)Cu-DOTA-E{E[c(RGDfK)](2)}(2) injection was estimated to be 0.0164 mSv/MBq.The high integrin and avidity and favorable biokinetics make (64)Cu-DOTA-E{E[c(RGDfK)](2)}(2) a promising agent for peptide receptor radionuclide imaging and therapy of integrin-positive tumors.

    View details for Web of Science ID 000232452700033

    View details for PubMedID 16204722

  • [99(m)TcOAADT]-(CH2)(2)-NEt2: A potential small-molecule single-photon emission computed tomography probe for Imaging metastatic melanoma CANCER RESEARCH Cheng, Z., Mahmood, A., Li, H. Z., Davison, A., Jones, A. G. 2005; 65 (12): 4979-4986


    Evaluation of [99mTc]oxotechnetium(V) complexes of the amine-amide-dithiol (AADT) chelates containing tertiary amine substituents as small-molecule probes for the diagnostic imaging of metastatic melanoma has shown that technetium-99m-labeled AADT-(CH2)2-NEt2 (99mTc-1) has the highest tumor uptake and other favorable biological properties. We have, therefore, assessed this agent in a more realistic metastatic melanoma model in which, after i.v. tail injection, a highly invasive melanoma cell line, B16F10, forms pulmonary tumor nodules in normal C57BL6 mice. Small melanotic lesions develop in the lungs and, on histologic examination, appear as small black melanoma colonies, increasing in size and number with time after tumor cell injection. Groups of mice received tumor cell inocula of 2 x 10(5), 4 x 10(5), or 8 x 10(5) B16F10 cells; 14 days later, 2 hours after 99mTc-1 administration, lung uptake of 2.83 +/- 0.21%, 3.63 +/- 1.07%, and 4.92 +/- 1.61% injected dose per gram of tissue (% ID/g), respectively, was observed, compared with normal lung uptake of 2.13 +/- 0.2% ID/g (P < 0.05). Additionally, a higher level of 99mTc-1 accumulation was seen 17 days after tumor cell inoculation as the lung lesions grew. These in vivo studies coupled with additional in vitro and ex vivo assessment show that 99mTc-1 has high and specific uptake in melanoma metastases in lungs and can potentially follow the temporal growth of these tumors.

    View details for Web of Science ID 000229734300003

    View details for PubMedID 15958536

  • A new strategy to screen molecular imaging probe uptake in cell culture without radiolabeling using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry JOURNAL OF NUCLEAR MEDICINE Cheng, Z., Winant, R. C., Gambhir, S. S. 2005; 46 (5): 878-886


    Numerous new molecular targets for diseases are rapidly being identified and validated in the postgenomic era, urging scientists to explore novel techniques for accelerating molecular probe development. In this study, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was investigated as a potential tool for high-throughput screening and characterization of molecular imaging probes. Specifically, MALDI-TOF-MS was used to screen a small library of phosphonium cations for their ability to accumulate in cells.C6 cells incubated with phosphonium cations at room temperature were collected and lysed for experiments. Calibration curves for the internal standard, methyltriphenyl phosphonium, and for tetraphenylphosphonium bromide (TPP) and other phosphonium cations were first established. The time course of TPP uptake by C6 cells was then quantified using both MALDI-TOF-MS and liquid scintillation counting with (3)H-TPP. In addition, MALDI-TOF-MS was used to screen a library of 8 phosphonium cations and subsequently rank their ability to penetrate membranes and accumulate in cells. Finally, the accumulation of 4-fluorophenyltriphenyl phosphonium (FTPP) in the membrane potential-modulated cells was also measured by MALDI-TOF-MS.MALDI-TOF-MS spectra clearly revealed that TPP was easily identified from cell lysates even as early as 10 min after incubation and that levels as low as 0.11 fmol of TPP per cell could be detected, suggesting the high sensitivity of this technique. The time course of TPP influx determined by both MALDI-TOF-MS and radioactivity counting showed no statistically significant difference (P > 0.05 for all time points). These data validated MALDI-TOF-MS as an alternative approach for accurately measuring uptake of phosphonium cations by cells. TPP and FTPP demonstrated greater accumulation in cells than did the other cations evaluated in this study. Furthermore, uptake profiles suggested that FTPP preserves the membrane potential-dependent uptake property of TPP in cell cultures. Taken together, these data justify further synthesis and evaluation of (18)F-FTPP as a molecular probe for imaging mitochondrial dysfunction.These results demonstrate that MALDI-TOF-MS is a powerful analytic tool for rapid screening and characterization of phosphonium cations as molecular probes. This technique can potentially be applied to the evaluation of other imaging probes or drugs and thus may facilitate their rational design and development.

    View details for Web of Science ID 000228952400030

    View details for PubMedID 15872363

  • Synthesis of (4-[F-18]fluorophenyl)triphenylphosphonium as a potential imaging agent for mitochondrial dysfunction JOURNAL OF LABELLED COMPOUNDS & RADIOPHARMACEUTICALS Cheng, Z., Subbarayan, M., Chen, X. Y., Gambhir, S. S. 2005; 48 (2): 131-137

    View details for DOI 10.1002/jlcr.906

    View details for Web of Science ID 000227120300006

  • Radioiodination of rhenium cyclized alpha-melanocyte-stimulating hormone resulting in enhanced radioactivity localization and retention in melanoma CANCER RESEARCH Cheng, Z., Chen, J. Q., Quinn, T. P., Jurisson, S. S. 2004; 64 (4): 1411-1418


    Radiohalogenated alpha-melanocyte-stimulating hormone (alpha-MSH) analogs were proposed for melanoma imaging and potential radiotherapy because alpha-MSH receptors are overexpressed on both mouse and human melanoma cell lines. However, biodistribution studies in tumor-bearing mice with radiohalogenated alpha-MSH peptides showed very rapid tumor radioactivity wash out due to lysosomal degradation of the radiohalogenated complex after internalization, which decreased the therapeutic efficacy significantly (R. Stein et al., Cancer Res., 55: 3132-3139, 1995; P. K. Garg et al., Bioconjugate Chem., 6: 493-501, 1995.). The melanoma-targeting metallopeptide ReO[Cys(3,4,10),D-Phe(7)]alpha-MSH(3-13) (ReCCMSH) was shown to possess high tumor uptake and retention properties (J. Chen et al., Cancer Res., 60: 5649-5658, 2000). Therefore, three peptides, Ac-Lys-ReCCMSH(Arg(11)), Ac-D-Lys-ReCCMSH(Arg(11)), and [Nle(4),D-Phe(7)]alpha-MSH (NDP) (for comparison), labeled with N-succinimidyl 4-[(125)I]iodobenzoate ((125)I-PIB), were prepared and evaluated in vitro and in vivo to develop radiohalogenated alpha-MSH peptide analogs with high tumor uptake, retention, and favorable biodistribution characteristics. In vitro cell binding and internalization data showed that approximately 90% of radioiodinated peptides were internalized at 2 h in cultured B16/F1 melanoma cells. Cellular retention studies showed that the receptor-bound radioiodinated linear alpha-MSH analog NDP was released from the cells into the medium very quickly, whereas significant amounts of cell-associated radioactivity remained in the cells for Ac-Lys((125)I-3- or 4-iodobenzoate (IBA))-ReCCMSH(Arg(11)) and Ac-D-Lys((125)I-IBA)-ReCCMSH(Arg(11)). The in vitro data clearly demonstrate that rhenium cyclization significantly enhanced peptide trapping in the cells, as did D-amino acid incorporation. The combination of these two effects resulted in a 2.9-fold increase in the retention of radioactivity for Ac-D-Lys((125)I-IBA)-ReCCMSH(Arg(11)) relative to (125)I-IBA-NDP at 4 h. In vivo studies also showed that Ac-D-Lys((125)I-IBA)-ReCCMSH(Arg(11)) exhibited extremely high radioactivity accumulation and prolonged retention in the tumor. Ac-D-Lys((125)I-IBA)-ReCCMSH(Arg(11)) and Ac-Lys((125)I-IBA)-ReCCMSH(Arg(11)) exhibited much higher tumor uptake at 24 h after injection compared with (125)I-IBA-NDP [7.18% injected dose/gram (ID/g), 4.92% ID/g, and 0.26% ID/g, respectively]. Ac-D-Lys((125)I-IBA)-ReCCMSH(Arg(11)) also showed very fast whole body clearance and low nonspecific radioactivity accumulation in normal tissues compared with (125)I-IBA-NDP and Ac-Lys((125)I-IBA)-ReCCMSH(Arg(11)). A tumor:blood ratio of 34.3 was observed for Ac-D-Lys((125)I-IBA)-ReCCMSH(Arg(11)) at 24 h postinjection, whereas values of 4.3 and 2.0 were observed for Ac-Lys((125)I-IBA)-ReCCMSH(Arg(11)) and (125)I-IBA-NDP, respectively. The biodistribution data clearly demonstrate that both rhenium cyclization and D-Lys incorporation enhanced the tumor localization and retention of the radiolabel. Therefore Ac-D-Lys-ReCCMSH(Arg(11)) is an excellent candidate for additional therapeutic studies.

    View details for Web of Science ID 000189245200029

    View details for PubMedID 14973076

  • Modification of the structure of a metallopeptide: Synthesis and biological evaluation of In-111-labeled DOTA-conjugated rhenium-cyclized alpha-MSH analogues JOURNAL OF MEDICINAL CHEMISTRY Cheng, Z., Chen, J. Q., Miao, Y. B., Owen, N. K., Quinn, T. P., Jurisson, S. S. 2002; 45 (14): 3048-3056


    Rhenium-cyclized CCMSH analogues are novel melanoma-targeting metallopeptides with high tumor uptake, long tumor retention, and low background in normal tissues, which make these metallopeptides an ideal structural motif for designing novel melanoma-targeting agents. ReCCMSH has been derivatized with a 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelate so that it can be labeled with a wide variety of radionuclides for imaging and therapeutic applications. This study involved optimization of the in vivo biological properties of DOTA-ReCCMSH (S), through modification of the structure of the metallopeptide. Several DOTA-ReCCMSH analogues, Ac-Lys(DOTA)-ReCCMSH (4) DOTA-ReCCMSH(Arg(11)) (6), DOTA-ReCCMSH-OH (8), and DOTA-ReCCMSH-Asp-OH (10), were synthesized using solid phase peptide synthesis followed by rhenium cyclization. The IC(50) values of the metallopeptides were determined through competitive binding assays against (125)I-(Tyr(2))-NDP. Radiolabeling of the DOTA-rhenium-cyclized peptides with (111)In was carried out in NH(4)OAc (0.1 M; pH 5.5)-buffered solution for 30 min at 70 degrees C. The stability of the radiolabeled complexes was evaluated in 0.01 M, pH 7.4, phosphate-buffered saline/0.1% bovine serum albumin solution. After separation of the radiolabeled peptide from the unlabeled peptide by reverse phase high-performance liquid chromatography, the biodistribution of the radiolabeled complex was performed in C57 mice bearing B16/F1 murine melanoma tumors. All radiolabeled complexes showed fast blood clearance (2 h postinjection (pi): (111)In-S, 0.07 +/- 0.03% ID/g; (111)In-4, 0.09 +/- 0.06% ID/g; (111)In-6, 0.21 +/- 0.08% ID/g; (111)In-8, 0.11 +/- 0.10% ID/g; and (111)In-10, 0.05 +/- 0.03% ID/g), and their clearance was predominantly through the urine (4 h pi: 93.5 +/- 1.7, 87.8 +/- 6.5, 89.8 +/- 4.2, 93.3 +/- 1.1, and 93.8 +/- 1.8 (% ID) for (111)In-labeled S, 4, 6, 8, and 10, respectively). Tumor uptake values of 9.45 +/- 0.90, 6.01 +/- 2.36, 17.41 +/- 5.61, 9.27 +/- 0.68, and 7.32 +/- 2.09 (% ID/g) for (111)In-labeled S, 4, 6, 8, and 10, respectively, were observed at 4 h pi. The kidney uptake was 9.27 +/- 2.65% ID/g for (111)In-S, 19.02 +/- 2.63% ID/g for (111)In-4, 7.37 +/- 1.13% ID/g for (111)In-6, 8.70 +/- 0.88% ID/g for (111)In-8, and 8.13 +/- 1.47% ID/g for (111)In-10 at 4 h pi. Complex 6 showed high melanoma uptake and lower kidney uptake than the corresponding Lys(11) analogues, supporting 6 for further investigations as a potential therapeutic radiopharmaceutical.

    View details for DOI 10.1021/jm010408m

    View details for Web of Science ID 000176664900016

    View details for PubMedID 12086490

  • alpha-melanocyte-stimulating hormone peptide analogs labeled with technetium-99m and indium-111 for malignant melanoma targeting 8th Conference on Radioimmunodetection and Radioimmunotherapy of Cancer Chen, J. Q., Cheng, Z., Miao, Y. B., Jurisson, S. S., Quinn, T. P. JOHN WILEY & SONS INC. 2002: 1196–1201


    Previous studies have shown that the compact structure of a rhenium-cyclized alpha--melanocyte-stimulating hormone peptide analog, [Cys3410,D-Phe7]alpha-MSH(3--13), or Re-CCMSH, significantly enhanced its in vivo tumor uptake and retention. In this study, the metal chelate 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) was coupled to the N-terminus of Re-CCMSH in order to develop a melanoma-targeting peptide that could be labeled with a wider variety of imaging and therapeutic radionuclides.Biodistribution properties of indium-111 ((111)In)--labeled DOTA-Re-CCMSH were compared with the non-DOTA-containing technetium-99m ((99m)Tc)--CCMSH in murine melanoma--bearing C57 mice to determine the effects of DOTA on tumor uptake and whole-body clearance. The tumor targeting capacity and clearance kinetics of (111)In-DOTA-Re-CCMSH were also compared with other related cyclic and linear (111)In-labeled DOTA-alpha-MSH complexes.The in vivo distribution data showed that the conjugation of DOTA to Re-CCMSH did not reduce its initial tumor uptake kinetics but did enhance its tumor retention and renal clearance properties. The tumor uptake of (111)In-DOTA-Re-CCMSH was significantly higher than the other (111)In-DOTA--coupled cyclic or linear alpha-MSH analogs used in this study. Moreover, (111)In-DOTA-Re-CCMSH displayed lower radioactivity accumulation in normal tissues of interest than its non-Re-cyclized counterpart, (111)In-DOTA-CCMSH; the disulfide bond--cyclized (111)In-DOTA-CMSH; or the linear (111)In-DOTA-NDP.Peptide cyclization via rhenium coordination significantly enhanced the tumor targeting and renal clearance properties of DOTA-Re-CCMSH, making it an excellent candidate for melanoma radiodetection and radiotherapy.

    View details for DOI 10.1002/cncr.10284

    View details for Web of Science ID 000173958100002

    View details for PubMedID 11877745

  • Differential in-vivo behavior of Tc(V)Oxo N2S2 complexes with melanoma affinity. Technetium, Rhenium and other Metals in Chemistry and Nuclear Medicine, Malago E, Mahmood A, Cheng Z, Kramer DJ, Friebe M, Eisenhut M, Davison A, Jones AG. 2002; 6: 419-421
  • Evaluation of [99mTcOAADT]-(CH2)2-N(Et)2 in a metastatic melanoma lung model. Technetium, Rhenium and other Metals in Chemistry and Nuclear Medicine, Cheng Z, M. L. 2002; 6: 423-425
  • Evaluation of an In-111-DOTA-rhenium cyclized alpha-MSH analog: A novel cyclic-peptide analog with improved tumor-targeting properties JOURNAL OF NUCLEAR MEDICINE Chen, J. Q., Cheng, Z., Owen, N. K., Hoffman, T. J., Miao, Y. B., Jurisson, S. S., Quinn, T. P. 2001; 42 (12): 1847-1855


    The aim of this study was to examine the effect of rhenium-mediated peptide cyclization on melanoma targeting, biodistribution, and clearance kinetics of the alpha-melanocyte-stimulating hormone (alpha-MSH) analog 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) coupled ReO-cyclized [Cys(3,4,10),D-Phe(7)]alpha-MSH(3-13) (DOTA-ReCCMSH).DOTA-ReCCMSH was compared with its reduced nonmetalated linear homolog, DOTA-CCMSH, and an analog in which rhenium cyclization was replaced by disulfide bond cyclization, DOTA-[Cys(4,10),D-Phe(7)]alpha-MSH(4-13) (CMSH). DOTA was also conjugated to the amino terminus of one of the highest-affinity alpha-MSH receptor-binding peptides, [Nle(4),D-Phe(7)]alpha-MSH (NDP), as a linear peptide standard. The DOTA-conjugated alpha-MSH analogs were radiolabeled with (111)In and examined for their in vitro receptor-binding affinity with B16/F1 murine melanoma cells, and their in vivo biodistribution properties were evaluated and compared in melanoma tumor-bearing C57 mice.The tumor uptake values of (111)In-DOTA-ReCCMSH were significantly higher than those of the other closely related (111)In-DOTA-alpha-MSH conjugates. Even at 24 h after injection, a comparison of the tumor uptake values for (111)In-DOTA-coupled ReCCMSH (4.86 +/- 1.52 percentage injected dose [%ID]/g), CCMSH (1.91 +/- 0.56 %ID/g), CMSH (3.09 +/- 0.32 %ID/g), and NDP (2.47 +/- 0.79 %ID/g) highlighted the high tumor retention property of ReCCMSH. Rhenium-coordinated cyclization resulted in less renal radioactivity accumulation of (111)In-DOTA-ReCCMSH (8.98 +/- 0.82 %ID/g) than of (111)In-DOTA-CCMSH (63.2 +/- 15.6 %ID/g), (111)In-DOTA-CMSH (38.4 +/- 3.6 %ID/g), and (111)In-DOTA-NDP (12.0 +/- 1.96 %ID/g) at 2 h after injection and significantly increased its clearance into the urine (92 %ID at 2 h after injection). A high radioactivity uptake ratio of tumor to normal tissue was obtained for (111)In-DOTA-ReCCMSH (e.g., 489, 159, 100, and 49 for blood, muscle, lung, and liver, respectively, at 4 h after injection).The novel ReO-coordinated cyclic structure of DOTA-ReCCMSH contributes significantly to its enhanced tumor-targeting and renal clearance properties and makes DOTAReCCMSH an excellent candidate for melanoma radiodetection and radiotherapy.

    View details for Web of Science ID 000172843200029

    View details for PubMedID 11752084

  • Melanoma-targeting properties of (99m)technetium-labeled cyclic alpha-melanocyte-stimulating hormone peptide analogues CANCER RESEARCH Chen, J. Q., Cheng, Z., Hoffman, T. J., Jurisson, S. S., Quinn, T. P. 2000; 60 (20): 5649-5658


    Preliminary reports have demonstrated that (99m)technetium (Tc)-labeled cyclic [Cys(3,4,10), D-Phe7]alpha-MSH(3-13) (CCMSH) exhibits high tumor uptake and retention values in a murine melanoma mouse model. In this report, the tumor targeting mechanism of 99mTc-CCMSH was studied and compared with four other radiolabeled alpha-melanocyte stimulating hormone (alpha-MSH) peptide analogues: 125I-(Tyr2)-[Nle4, D-Phe7]alpha-MSH [125I-(Tyr2)-NDP]; 99mTc-CGCG-NDP; 99mTc-Gly11-CCMSH; and 99mTc-Nle11-CCMSH. In vitro receptor binding, internalization, and cellular retention of radiolabeled alpha-MSH analogues in B16/F1 murine cell line demonstrated that >70% of the receptor-bound radiolabeled analogues were internalized together with the receptor. Ninety % of the internalized 125I-(Tyr2)-NDP, whereas only 36% of internalized 99mTc-CCMSH, was released from the cells into the medium during a 4-h incubation at 37 degrees C. Two mouse models, C57 mice and severe combined immunodeficient (Scid) mice, inoculated s.c. with B16/F1 murine and TXM-13 human melanoma cells were used for the in vivo studies. Tumor uptake values of 11.32 and 2.39 [% injected dose (ID)/g] for 99mTc-CCMSH at 4 h after injection, resulted in an uptake ratio of tumor:blood of 39.0 and 11.5 in murine melanoma-C57 and human melanoma-Scid mouse models, respectively. Two strategies for decreasing the nonspecific kidney uptake of 99mTc-CCMSH, substitution of Lys11 in CCMSH with Gly11 or Nle11, and lysine coinjection, were evaluated. The biodistribution data for the modified peptides showed that Lys11 replacement dramatically decreased the kidney uptake, whereas the tumor uptakes of 99mTc-Nle11- and 99mTc-Gly11-CCMSH were significantly lower than that of 99mTc-CCMSH. Lysine coinjection significantly decreased the kidney uptake (e.g., from 14.6% ID/g to 4.5% ID/g at 4 h after injection in murine melanoma-C57 mice) without significantly changing the value of tumor uptake of 99mTc-CCMSH. In conclusion, the compact cyclic structure of 99mTc-CCMSH, its resistance to degradation, and its enhanced intracellular retention are the major contributing factors to the superior in vivo tumor targeting properties of 99mTc-CCMSH. Lys11 residue in 99mTc-CCMSH is critical to the tumor targeting in vivo, and lysine coinjection rather than lysine replacement can significantly decrease the nonspecific renal radioactivity accumulation without impeding the high melanoma-targeting properties of 99Tc-CCMSH. The metal-cyclized CCMSH molecule displays excellent potential for the development of melanoma-specific diagnostic and therapeutic agents.

    View details for Web of Science ID 000090054800013

    View details for PubMedID 11059756

  • Quality control studies of Tc-99m-DTPA-octreotide by RP-HPLC J Radioanal Nucl Chem Cheng Z, L. J. 1998; 236: 97-101
  • Labeling conditions studies of Tyr3-octreotide with 131I and its biodistribution in mouse Journal of Isotopes Fan HQ, W. J. 1998; 11 (1): 29-33
  • HPLC analysis of radiolabeled octreotide. J Radioanal Nucl Chem Wang F, F. C. 1998; 236: 205-7
  • Preparation of Sm-153-resin micorosphere and determination of femoral head blood flow of rabbits. Journal of Isotopes Bai HS, C. J., Zhang NF, Yang L, Li ZR. 1998; 11 (1): 39-43
  • Study on analysis of Sm-153-EDTMP stability in vitro and in vivo by HPLC. J Radioanal Nucl Chem Bai HS, J. F. 1998; 236: 87-95
  • Labeling study on In-111-octreotide and primary animal tests. Journal of Isotopes Wang F, F. X. 1997; 10 (1): 16-20
  • Development of 99mTc-DTPA-octreotide somatostaton receptor imaging agent. I. studying of labeling conditions. Journal of Isotopes Cheng Z, Lin QF, Jin XH. 1997; 10 (3): 150-157
  • Preparation of Sm-153-Cl2MDP and preliminary animal test. Nuclear Techniques. Bai HS, Du J, Cheng Z, Fan HQ, Wang F, Chen DM, Jin XH. 1997; 20 (11): 699-701
  • Preparation of 166Ho-EDTMP-hydroxyapatite for radiation synovectomy. Nuclear Techniques Bai HS, Jin XH, Du J, Wang F, Chen DM, Fan HQ, Cheng Z. 1997; 20 (11): 691-695
  • Preliminary study on a potential tumor radiotherapy agent: 186Re(V)-DMSA. Journal of Isotopes. Chen DM, Jin XH, Du J, Wang F, Bai HS, Xu H, Cheng Z, Chen S, Qi X, Zhao X, Lu X. 1997; 10 (2): 109-112