Dr. Moding is a physician scientist in the Department of Radiation Oncology at Stanford University. Clinically, he focuses on the treatment of patients with sarcomas using radiation therapy, and he is engaged in prospective and retrospective clinical research. He has diverse research expertise in pre-clinical models and next-generation sequencing based approaches to analyze human samples. He has used genetically engineered mouse models to study radiation biology and the contribution of the tumor microenvironment to cancer development and response to therapy. In addition, he has applied tumor genomics, transcriptomics, and circulating tumor DNA analysis to enable personalization of radiation therapy and other treatments in human cancers.

Clinical Focus

  • Radiation Oncology
  • Neoplasms, Connective and Soft Tissue

Honors & Awards

  • Barnes Chemistry Scholarship, Colorado College (8/2004-5/2008)
  • First Year Chemistry Award, Colorado College (5/2005)
  • William C. Champion Prize in Organic Chemistry, Colorado College (5/2006)
  • American Chemistry Society Analytical Chemistry Award, Colorado College (5/2007)
  • Summa Cum Laude, Colorado College (5/2008)
  • Phi Beta Kappa Honor Society, Colorado College (5/2008)
  • Merck Index Award in Biochemistry, Colorado College (5/2008)
  • Frank Henry John Figge Award, Colorado College (5/2008)
  • Alpha Lambda Delta Book Award, Colorado College (5/2008)
  • Medical Scientist Training Program Fellowship, National Institutes of Health (8/2008-5/2015)
  • Space Radiation Summer School Scholar, NASA (6/2011)
  • Fitzgerald Academic Achievement Award, Duke University Department of Pharmacology and Cancer Biology (3/2013)
  • Basic Science Abstract Award, ASTRO Annual Meeting (9/2014)
  • Best Abstract Selection, ASTRO Annual Meeting (10/2014)
  • B. Leonard Holman Research Pathway, American Board of Radiology (7/2018-6/2020)
  • Kaplan Fellowship, Stanford University Department of Radiation Oncology (7/2019-6/2020)
  • Fellows’ Forum Participant, Society for Translational Oncology (1/2020)
  • Young Investigator Award, Connective Tissue Oncology Society (11/2021)
  • Invited Collaborative Researcher, Global Center for Biomedical Science and Engineering, Hokkaido University (4/2023)
  • Sarah Donaldson Mentorship Award, Stanford Radiation Oncology (6/2023)

Boards, Advisory Committees, Professional Organizations

  • Member, Radiation Research Society (2012 - Present)
  • Member, American College of Radiology (2016 - Present)
  • Member, Radiological Society of North America (2016 - Present)
  • Member, American Society for Radiation Oncology (2017 - Present)
  • Member, American Association for Cancer Research (2018 - Present)
  • Member, American Society of Clinical Oncology (2019 - Present)
  • Member, Connective Tissue Oncology Society (2022 - Present)

Professional Education

  • BA, Colorado College, Biochemistry (2008)
  • PhD, Duke University School of Medicine, Molecular Cancer Biology (2015)
  • MD, Duke University School of Medicine, Medicine (2015)
  • Internship, Moses H. Cone Memorial Hospital, Internal Medicine (2016)
  • Residency, Stanford University Medical Center, Radiation Oncology (2020)
  • Board Certification: American Board of Radiology, Radiation Oncology (2021)

Current Research and Scholarly Interests

My laboratory focuses on three main areas: 1) studying the genetics underlying the response of tumors to radiation therapy, 2) developing personalized treatment approaches for sarcomas, and 3) understanding tumor clonal evolution during cancer therapy. We perform translational cancer research by analyzing human tissue and blood samples with next-generation sequencing to understand the genetic underpinnings and expression signatures that determine treatment response and resistance. We use genetically engineered mouse models to validate our findings, perform mechanistic experiments, and test new therapies.

Clinical Trials

  • 5-Day Preoperative Radiation for Soft Tissue Sarcoma Recruiting

    The purpose of this study is to examine the safety and efficacy of an abbreviated course of preoperative radiation, given over five days, for patients with soft tissue sarcoma of the extremity, trunk or retroperitoneum. This is in contrast to standard preoperative radiation, which is given over 25 days.

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2023-24 Courses

Stanford Advisees

All Publications

  • Sarcoma microenvironment cell states and ecosystems are associated with prognosis and predict response to immunotherapy. Nature cancer Subramanian, A., Nemat-Gorgani, N., Ellis-Caleo, T. J., van IJzendoorn, D. G., Sears, T. J., Somani, A., Luca, B. A., Zhou, M. Y., Bradic, M., Torres, I. A., Oladipo, E., New, C., Kenney, D. E., Avedian, R. S., Steffner, R. J., Binkley, M. S., Mohler, D. G., Tap, W. D., D'Angelo, S. P., van de Rijn, M., Ganjoo, K. N., Bui, N. Q., Charville, G. W., Newman, A. M., Moding, E. J. 2024


    Characterization of the diverse malignant and stromal cell states that make up soft tissue sarcomas and their correlation with patient outcomes has proven difficult using fixed clinical specimens. Here, we employed EcoTyper, a machine-learning framework, to identify the fundamental cell states and cellular ecosystems that make up sarcomas on a large scale using bulk transcriptomes with clinical annotations. We identified and validated 23 sarcoma-specific, transcriptionally defined cell states, many of which were highly prognostic of patient outcomes across independent datasets. We discovered three conserved cellular communities or ecotypes associated with underlying genomic alterations and distinct clinical outcomes. We show that one ecotype defined by tumor-associated macrophages and epithelial-like malignant cells predicts response to immune-checkpoint inhibition but not chemotherapy and validate our findings in an independent cohort. Our results may enable identification of patients with soft tissue sarcomas who could benefit from immunotherapy and help develop new therapeutic strategies.

    View details for DOI 10.1038/s43018-024-00743-y

    View details for PubMedID 38429415

    View details for PubMedCentralID 4486342

  • Monitoring sarcoma response to immune checkpoint inhibition and local cryotherapy with circulating tumor DNA analysis. Clinical cancer research : an official journal of the American Association for Cancer Research Bui, N. Q., Nemat-Gorgani, N., Subramanian, A., Torres, I. A., Lohman, M., Sears, T. J., van de Rijn, M., Charville, G. W., Becker, H. C., Wang, D. S., Hwang, G. L., Ganjoo, K. N., Moding, E. J. 2023


    Immune checkpoint inhibition has led to promising responses in soft tissue sarcomas (STSs), but the majority of patients do not respond and biomarkers of response will be crucial. Local ablative therapies may augment systemic responses to immunotherapy. We evaluated circulating tumor DNA (ctDNA) as a biomarker of response in patients treated on a trial combining immunotherapy with local cryotherapy for advanced STSs.We enrolled 30 patients with unresectable or metastatic STS to a phase 2 clinical trial. Patients received ipilimumab and nivolumab for 4 doses followed by nivolumab alone with cryoablation performed between cycles 1 and 2. The primary endpoint was objective response rate (ORR) by 14 weeks. Personalized ctDNA analysis using bespoke panels was performed on blood samples collected prior to each immunotherapy cycle.ctDNA was detected in at least one sample for 96% of patients. Pre-treatment ctDNA allele fraction was negatively associated with treatment response, progression-free survival (PFS), and overall survival (OS). ctDNA increased in 90% of patients from pre-treatment to post-cryotherapy, and patients with a subsequent decrease in ctDNA or undetectable ctDNA after cryotherapy had significantly better PFS. Of the 27 evaluable patients, the ORR was 4% by RECIST and 11% by irRECIST. Median PFS and OS were 2.7 and 12.0 months, respectively. No new safety signals were observed.ctDNA represents a promising biomarker for monitoring response to treatment in advanced STS, warranting future prospective studies. Combining cryotherapy and immune checkpoint inhibitors did not increase the response rate of STSs to immunotherapy.

    View details for DOI 10.1158/1078-0432.CCR-23-0250

    View details for PubMedID 37130154

  • Detecting Liquid Remnants of Solid Tumors: Circulating Tumor DNA Minimal Residual Disease. Cancer discovery Moding, E. J., Nabet, B. Y., Alizadeh, A. A., Diehn, M. 2021


    Growing evidence demonstrates that circulating tumor DNA (ctDNA) minimal residual disease (MRD) following treatment for solid tumors predicts relapse. These results suggest that ctDNA MRD could identify candidates for adjuvant therapy and measure response to such treatment. Importantly, factors such as assay type, amount of ctDNA release, and technical and biological background can affect ctDNA MRD results. Furthermore, the clinical utility of ctDNA MRD for treatment personalization remains to be fully established. Here, we review the evidence supporting the value of ctDNA MRD in solid cancers and highlight key considerations in the application of this potentially transformative biomarker. SIGNIFICANCE: ctDNA analysis enables detection of MRD and predicts relapse after definitive treatment for solid cancers, thereby promising to revolutionize personalization of adjuvant and consolidation therapies.

    View details for DOI 10.1158/2159-8290.CD-21-0634

    View details for PubMedID 34785539

  • Circulating Tumor DNA Dynamics Predict Benefit from Consolidation Immunotherapy in Locally Advanced Non-Small Cell Lung Cancer. Nature cancer Moding, E. J., Liu, Y., Nabet, B. Y., Chabon, J. J., Chaudhuri, A. A., Hui, A. B., Bonilla, R. F., Ko, R. B., Yoo, C. H., Gojenola, L., Jones, C. D., He, J., Qiao, Y., Xu, T., Heymach, J. V., Tsao, A., Liao, Z., Gomez, D. R., Das, M., Padda, S. K., Ramchandran, K. J., Neal, J. W., Wakelee, H. A., Loo, B. W., Lin, S. H., Alizadeh, A. A., Diehn, M. 2020; 1 (2): 176-183


    Circulating tumor DNA (ctDNA) molecular residual disease (MRD) following curative-intent treatment strongly predicts recurrence in multiple tumor types, but whether further treatment can improve outcomes in patients with MRD remains unclear. We applied CAPP-Seq ctDNA analysis to 218 samples from 65 patients receiving chemoradiation therapy (CRT) for locally advanced NSCLC, including 28 patients receiving consolidation immune checkpoint inhibition (CICI). Patients with undetectable ctDNA after CRT had excellent outcomes whether or not they received CICI. Among such patients, one died from CICI-related pneumonitis, highlighting the potential utility of only treating patients with MRD. In contrast, patients with MRD after CRT who received CICI had significantly better outcomes than patients who did not receive CICI. Furthermore, the ctDNA response pattern early during CICI identified patients responding to consolidation therapy. Our results suggest that CICI improves outcomes for NSCLC patients with MRD and that ctDNA analysis may facilitate personalization of consolidation therapy.

    View details for DOI 10.1038/s43018-019-0011-0

    View details for PubMedID 34505064

    View details for PubMedCentralID PMC8425388

  • Tumor cells, but not endothelial cells, mediate eradication of primary sarcomas by stereotactic body radiation therapy SCIENCE TRANSLATIONAL MEDICINE Moding, E. J., Castle, K. D., Perez, B. A., Oh, P., Min, H. D., Norris, H., Ma, Y., Cardona, D. M., Lee, C., Kirsch, D. G. 2015; 7 (278): 278ra34


    Cancer clinics currently use high-dose stereotactic body radiation therapy as a curative treatment for several kinds of cancers. However, the contribution of vascular endothelial cells to tumor response to radiation remains controversial. Using dual recombinase technology, we generated primary sarcomas in mice with targeted genetic mutations specifically in tumor cells or endothelial cells. We selectively mutated the proapoptotic gene Bax or the DNA damage response gene Atm to genetically manipulate the radiosensitivity of endothelial cells in primary soft tissue sarcomas. Bax deletion from endothelial cells did not affect radiation-induced cell death in tumor endothelial cells or sarcoma response to radiation therapy. Although Atm deletion increased endothelial cell death after radiation therapy, deletion of Atm from endothelial cells failed to enhance sarcoma eradication. In contrast, deletion of Atm from tumor cells increased sarcoma eradication by radiation therapy. These results demonstrate that tumor cells, rather than endothelial cells, are critical targets that regulate sarcoma eradication by radiation therapy. Treatment with BEZ235, a small-molecule protein kinase inhibitor, radiosensitized primary sarcomas more than the heart. These results suggest that inhibiting ATM kinase during radiation therapy is a viable strategy for radiosensitization of some tumors.

    View details for PubMedID 25761890

    View details for PubMedCentralID PMC4360135

  • Atm deletion with dual recombinase technology preferentially radiosensitizes tumor endothelium JOURNAL OF CLINICAL INVESTIGATION Moding, E. J., Lee, C., Castle, K. D., Oh, P., Mao, L., Zha, S., Min, H. D., Ma, Y., Das, S., Kirsch, D. G. 2014; 124 (8): 3325–38


    Cells isolated from patients with ataxia telangiectasia are exquisitely sensitive to ionizing radiation. Kinase inhibitors of ATM, the gene mutated in ataxia telangiectasia, can sensitize tumor cells to radiation therapy, but concern that inhibiting ATM in normal tissues will also increase normal tissue toxicity from radiation has limited their clinical application. Endothelial cell damage can contribute to the development of long-term side effects after radiation therapy, but the role of endothelial cell death in tumor response to radiation therapy remains controversial. Here, we developed dual recombinase technology using both FlpO and Cre recombinases to generate primary sarcomas in mice with endothelial cell-specific deletion of Atm to determine whether loss of Atm in endothelial cells sensitizes tumors and normal tissues to radiation. Although deletion of Atm in proliferating tumor endothelial cells enhanced the response of sarcomas to radiation, Atm deletion in quiescent endothelial cells of the heart did not sensitize mice to radiation-induced myocardial necrosis. Blocking cell cycle progression reversed the effect of Atm loss on tumor endothelial cell radiosensitivity. These results indicate that endothelial cells must progress through the cell cycle in order to be radiosensitized by Atm deletion.

    View details for DOI 10.1172/JCI73932

    View details for Web of Science ID 000339984000010

    View details for PubMedID 25036710

    View details for PubMedCentralID PMC4109553

  • Strategies for optimizing the response of cancer and normal tissues to radiation NATURE REVIEWS DRUG DISCOVERY Moding, E. J., Kastan, M. B., Kirsch, D. G. 2013; 12 (7): 526–42


    Approximately 50% of all patients with cancer receive radiation therapy at some point during the course of their treatment, and the majority of these patients are treated with curative intent. Despite recent advances in the planning of radiation treatment and the delivery of image-guided radiation therapy, acute toxicity and potential long-term side effects often limit the ability to deliver a sufficient dose of radiation to control tumours locally. In the past two decades, a better understanding of the hallmarks of cancer and the discovery of specific signalling pathways by which cells respond to radiation have provided new opportunities to design molecularly targeted therapies to increase the therapeutic window of radiation therapy. Here, we review efforts to develop approaches that could improve outcomes with radiation therapy by increasing the probability of tumour cure or by decreasing normal tissue toxicity.

    View details for PubMedID 23812271

  • Opportunity in Complexity: Harnessing Molecular Biomarkers and Liquid Biopsies for Personalized Sarcoma Care. Seminars in radiation oncology Ewongwo, A., Hui, C., Moding, E. J. 2024; 34 (2): 195-206


    Due to their rarity and complexity, sarcomas represent a substantial therapeutic challenge. However, the incredible diversity within and across sarcoma subtypes presents an opportunity for personalized care to maximize efficacy and limit toxicity. A deeper understanding of the molecular alterations that drive sarcoma development and treatment response has paved the way for molecular biomarkers to shape sarcoma treatment. Genetic, transcriptomic, and protein biomarkers have become critical tools for diagnosis, prognostication, and treatment selection in patients with sarcomas. In the future, emerging biomarkers like circulating tumor DNA analysis offer the potential to improve early detection, monitoring response to treatment, and identifying mechanisms of resistance to personalize sarcoma treatment. Here, we review the current state of molecular biomarkers for sarcomas and highlight opportunities and challenges for the implementation of new technologies in the future.

    View details for DOI 10.1016/j.semradonc.2023.12.002

    View details for PubMedID 38508784

  • Enhancing radiotherapy response via intratumoral injection of the TLR9 agonist CpG to stimulate CD8 T cells in an autochthonous mouse model of sarcoma. bioRxiv : the preprint server for biology Su, C., Kent, C. L., Pierpoint, M., Floyd, W., Luo, L., Wiliams, N. T., Ma, Y., Peng, B., Lazarides, A. L., Subramanian, A., Himes, J. E., Perez, V. M., Hernansaiz-Ballesteros, R. D., Roche, K. E., Modliszewski, J. L., Selitsky, S. R., Wisdom, A. J., Moding, E. J., Mowery, Y. M., Kirsch, D. G. 2024


    Radiation therapy is frequently used to treat cancers including soft tissue sarcomas. Prior studies established that the toll-like receptor 9 (TLR9) agonist cytosine-phosphate-guanine oligodeoxynucleotide (CpG) enhances the response to radiation therapy (RT) in transplanted tumors, but the mechanism(s) remain unclear. Here, we used CRISPR/Cas9 and the chemical carcinogen 3-methylcholanthrene (MCA) to generate autochthonous soft tissue sarcomas with high tumor mutation burden. Treatment with a single fraction of 20 Gy RT and two doses of CpG significantly enhanced tumor response, which was abrogated by genetic or immunodepletion of CD8+ T cells. To characterize the immune response to RT + CpG, we performed bulk RNA-seq, single-cell RNA-seq, and mass cytometry. Sarcomas treated with 20 Gy and CpG demonstrated increased CD8 T cells expressing markers associated with activation and proliferation, such as Granzyme B, Ki-67, and interferon-γ. CpG + RT also upregulated antigen presentation pathways on myeloid cells. Furthermore, in sarcomas treated with CpG + RT, TCR clonality analysis suggests an increase in clonal T-cell dominance. Collectively, these findings demonstrate that RT + CpG significantly delays tumor growth in a CD8 T cell-dependent manner. These results provide a strong rationale for clinical trials evaluating CpG or other TLR9 agonists with RT in patients with soft tissue sarcoma.

    View details for DOI 10.1101/2024.01.03.573968

    View details for PubMedID 38260522

    View details for PubMedCentralID PMC10802286

  • Predicting Adverse Cardiac Events After Radiotherapy for Locally Advanced Non-Small Cell Lung Cancer. JACC. CardioOncology No, H. J., Guo, F. B., Park, N. J., Kastelowitz, N., Rhee, J. W., Clark, D. E., Chin, A. L., Vitzthum, L. K., Horst, K. C., Moding, E. J., Loo, B. W., Diehn, M., Binkley, M. S. 2023; 5 (6): 775-787


    Radiotherapy may cause grade ≥3 cardiac events, necessitating a better understanding of risk factors. The potential predictive role of imaging biomarkers with radiotherapy doses for cardiac event occurrence has not been studied.The aim of this study was to establish the associations between cardiac substructure dose and coronary artery calcium (CAC) scores and cardiac event occurrence.A retrospective cohort analysis included patients with locally advanced non-small cell lung cancer treated with radiotherapy (2006-2018). Cardiac substructures, including the left anterior descending coronary artery, left main coronary artery, left circumflex coronary artery, right coronary artery, and TotalLeft (left anterior descending, left main, and left circumflex coronary arteries), were contoured. Doses were measured in 2-Gy equivalent units, and visual CAC scoring was compared with automated scoring. Grade ≥3 adverse cardiac events were recorded. Time-dependent receiver-operating characteristic modeling, the log-rank statistic, and competing-risk models were used to measure prediction performance, threshold modeling, and the cumulative incidence of cardiac events, respectively.Of the 233 eligible patients, 61.4% were men, with a median age of 68.1 years (range: 34.9-90.7 years). The median follow-up period was 73.7 months (range: 1.6-153.9 months). Following radiotherapy, 22.3% experienced cardiac events, within a median time of 21.5 months (range: 1.7-118.9 months). Visual CAC scoring showed significant correlation with automated scoring (r = 0.72; P < 0.001). In a competing-risk multivariable model, TotalLeft volume receiving 15 Gy (per 1 cc; HR: 1.38; 95% CI: 1.11-1.72; P = 0.004) and CAC score >5 (HR: 2.51; 95% CI: 1.08-5.86; P = 0.033) were independently associated with cardiac events. A model incorporating age, TotalLeft CAC (score >5), and volume receiving 15 Gy demonstrated a higher incidence of cardiac events for a high-risk group (28.9%) compared with a low-risk group (6.9%) (P < 0.001).Adverse cardiac events associated with radiation occur in more than 20% of patients undergoing thoracic radiotherapy within a median time of <2 years. The present findings provide further evidence to support significant associations between TotalLeft radiotherapy dose and cardiac events and define CAC as a predictive risk factor.

    View details for DOI 10.1016/j.jaccao.2023.08.007

    View details for PubMedID 38205000

    View details for PubMedCentralID PMC10774791

  • Patterns of local recurrence and risk of skin recurrence in soft tissue sarcomas after surgical resection. Practical radiation oncology Ewongwo, A., Oladipo, E. D., Hui, C., Avedian, R. S., Steffner, R. J., Mohler, D. G., Kalbasi, A., Chin, A. L., Million, L., Hiniker, S. M., Moding, E. J. 2023


    Although there is a theoretical risk of skin seeding during surgical resection of soft tissues sarcomas (STSs), current consensus guidelines recommend against routine use of bolus during RT. However, the risk of skin recurrence has not been systematically assessed. We aimed to assess the patterns of local recurrence (LR) in patients with STS treated with surgery with or without RT.We performed a retrospective analysis of adults with STSs evaluated at our institution between 2007-2021. For patients who developed LR, the depth was evaluated. Progression free survival (PFS) and overall survival (OS) were analyzed from time of first LR using Kaplan-Meier method. Cumulative incidence of distant metastasis (CIDM) was calculated with competing risk analysis from date of LR.Of the 206 patients evaluated, 20 had LR (9.7%). Among patients with LR, five patients (25.0%) were treated with surgery alone and 15 patients (75.0%) with surgery and RT. In patients treated with RT, 46.7% had pre-operative RT, 53.3% had post operative RT, and bolus was used in 46.7%. Surgical margins were close (<1mm) in 4 patients (20.0%) and positive in 10 patients (50.0%). LR occurred in the deep subfascial tissue in 9 patients (45%), subcutaneous tissue in 10 patients (50.0%), and skin in 1 patient (5.0%). The patient with a skin recurrence was treated with surgery alone and the tumor involved the skin at presentation. In patients treated with RT, LR occurred within RT field in 13 patients (86.7%). At 1 year after LR, PFS was 70.3%, OS was 81.7%, and CIDM was 5.9%.Skin recurrences were rare after surgical resection of STSs, and only occurred in a tumor that involved the skin at initial presentation. These findings support current recommendations against routine use of bolus in STSs not involving the skin at presentation.

    View details for DOI 10.1016/j.prro.2023.09.006

    View details for PubMedID 37804883

  • Characterizing the role of Phlda3 in the development of acute toxicity and malignant transformation of hematopoietic cells induced by total-body irradiation in mice. Scientific reports Hasapis, S., Caraballo, I., Sears, T. J., Brock, K. D., Cart, J. B., Moding, E. J., Lee, C. 2023; 13 (1): 12916


    The tumor suppressor p53 is a transcriptional factor that plays a crucial role in controlling acute toxicity and long-term malignant transformation of hematopoietic cells induced by genotoxic stress such as ionizing radiation. Among all transcriptional targets of p53, one gene that is robustly induced by radiation is the pleckstrin homology domain-only protein Phlda3. However, the role that Phlda3 plays in regulating the response of hematopoietic cells to radiation is unknown. Here, using isogenic cell lines and genetically engineered mouse models, we showed that radiation induces Phlda3 in human leukemia cells and mouse normal hematopoietic cells in a p53-dependent manner. However, deletion of the Phlda3 gene did not ameliorate radiation-induced acute hematologic toxicity. In addition, distinct from mice that lose p53, loss of Phlda3 did not alter the latency and incidence of radiation-induced thymic lymphoma in mice. Remarkably, whole-exome sequencing data showed that lymphomas in irradiated Phlda3+/+ mice harbor a significantly higher number of single nucleotide variants (SNVs) and indels compared to lymphomas in irradiated Phlda3+/- and Phlda3-/- littermates. Together, our results indicate that although deletion of Phlda3 does not accelerate the development of radiation-induced thymic lymphoma, fewer SNVs and indels are necessary to initiate lymphomagenesis after radiation exposure when Phlda3 is silenced.

    View details for DOI 10.1038/s41598-023-39678-2

    View details for PubMedID 37558703

  • Investigating the tissue specificity and prognostic impact of cis-regulatory cancer risk variants. Human genetics Subramanian, A., Su, S., Moding, E. J., Binkley, M. S. 2023


    The tissue-specific incidence of cancers and their genetic basis are poorly understood. Although prior studies have shown global correlation across tissues for cancer risk single-nucleotide polymorphisms (SNPs) identified through genome-wide association studies (GWAS), any shared functional regulation of gene expression on a per SNP basis has not been well characterized. We set to quantify cis-mediated gene regulation and tissue sharing for SNPs associated with eight common cancers. We identify significant tissue sharing for individual SNPs and global enrichment for breast, colorectal, and Hodgkin lymphoma cancer risk SNPs in multiple tissues. In addition, we observe increasing tissue sharing for cancer risk SNPs overlapping with super-enhancers for breast cancer and Hodgkin lymphoma providing further evidence of tissue specificity. Finally, for genes under cis-regulation by breast cancer SNPs, we identify a phenotype characterized by low expression of tumor suppressors and negative regulators of the WNT pathway associated with worse freedom from progression and overall survival in patients who eventually develop breast cancer. Our results introduce a paradigm for functionally annotating individual cancer risk SNPs and will inform the design of future translational studies aimed to personalize assessment of inherited cancer risk across tissues.

    View details for DOI 10.1007/s00439-023-02586-6

    View details for PubMedID 37474751

    View details for PubMedCentralID 7388212

  • Investigating and modeling positron emission tomography factors associated with large cell transformation from low-grade lymphomas. EJHaem Obeid, J. P., Hiniker, S. M., Schroers-Martin, J., Guo, H. H., No, H. J., Moding, E. J., Advani, R. H., Alizadeh, A. A., Hoppe, R. T., Binkley, M. S. 2023; 4 (1): 90-99


    Low-grade lymphomas have a 1%-3% annual risk of transformation to a high-grade histology, and prognostic factors remain undefined. We set to investigate the role of positron emission tomography (PET) metrics in identification of transformation in a retrospective case-control series of patients matched by histology and follow-up time. We measured PET parameters including maximum standard uptake value (SUV-max) and total lesion glycolysis (TLG), and developed a PET feature and lactate dehydrogenase (LDH)-based model to identify transformation status within discovery and validation cohorts. For our discovery cohort, we identified 53 patients with transformation and 53 controls with a similar distribution of follicular lymphoma (FL). Time to transformation and control follow-up time was similar. We observed a significant incremental increase in SUV-max and TLG between control, pretransformation and post-transformation groups (P < 0.05). By multivariable analysis, we identified a significant interaction between SUV-max and TLG such that SUV-max had highest significance for low volume cases (P = 0.04). We developed a scoring model incorporating SUV-max, TLG, and serum LDH with improved identification of transformation (area under the curve [AUC] = 0.91). Our model performed similarly for our validation cohort of 23 patients (AUC = 0.90). With external and prospective validation, our scoring model may provide a specific and noninvasive tool for risk stratification for patients with low-grade lymphoma.

    View details for DOI 10.1002/jha2.615

    View details for PubMedID 36819184

    View details for PubMedCentralID PMC9928791

  • Local control outcomes using stereotactic body radiotherapy or surgical resection for metastatic sarcoma. International journal of radiation oncology, biology, physics Gutkin, P. M., von Eyben, R., Chin, A., Donaldson, S. S., Oh, J., Jiang, A., Ganjoo, K. N., Avedian, R. S., Bruzoni, M., Steffner, R. J., Moding, E. J., Hiniker, S. M. 2022


    Traditional management of metastatic sarcoma primarily relies on systemic therapy, with surgery often used for tumor control. We analyzed the rates of recurrence, overall survival, and treatment complications in patients undergoing either surgical resection or stereotactic body radiotherapy (SBRT) for metastatic sarcoma of the bone and/or soft tissue.The records of patients with metastatic sarcoma between 2009-2020 were reviewed. Local recurrence (LR) was defined as tumor growth or recurrence at the tumor site. Cumulative local recurrence incidence was analyzed accounting for the competing risk of death, and groups were compared using the Gray test. Overall survival (OS) was assessed using the Kaplan Meier method and log-rank test. Hazard ratios were determined using Cox proportional test.A total of 525 metastatic lesions in 217 patients were analyzed. Mean age was 57 years (range 4-88). The lung was the predominant site treated (50%), followed by intra-abdominal (13%), and soft-tissue (11%). Two-year cumulative incidences of LR for surgery and SBRT were 14.8% (95% confidence interval [CI], 11.6-18.5) and 1.7% (95% CI, 0.1-8.2), respectively (p=0.003). LR occurred in 72/437 (16.5%) tumors treated with surgery and 2/88 (2.3%) tumors treated with SBRT. Adjusted hazard ratio for LR of lesions treated surgically was 11.5 (p=0.026) when controlled for tumor size and tumor site. Median OS was 29.8 months (95% CI, 25.6-40.9). There were 47 surgical complications of a total of 275 procedures (18%). Of 58 radiation treatment courses, radiation-related toxicity was reported during the treatment of 7 lesions (12%), and none were higher than grade 2.We observed excellent local control among patients selected for treatment with SBRT for metastatic sarcoma, with no evidence of increase in LR following SBRT when compared to surgical management. Further investigation is necessary to better define the most appropriate local control strategies for metastatic sarcoma.

    View details for DOI 10.1016/j.ijrobp.2022.05.017

    View details for PubMedID 35643255

  • Inferring gene expression from cell-free DNA fragmentation profiles. Nature biotechnology Esfahani, M. S., Hamilton, E. G., Mehrmohamadi, M., Nabet, B. Y., Alig, S. K., King, D. A., Steen, C. B., Macaulay, C. W., Schultz, A., Nesselbush, M. C., Soo, J., Schroers-Martin, J. G., Chen, B., Binkley, M. S., Stehr, H., Chabon, J. J., Sworder, B. J., Hui, A. B., Frank, M. J., Moding, E. J., Liu, C. L., Newman, A. M., Isbell, J. M., Rudin, C. M., Li, B. T., Kurtz, D. M., Diehn, M., Alizadeh, A. A. 2022


    Profiling of circulating tumor DNA (ctDNA) in the bloodstream shows promise for noninvasive cancer detection. Chromatin fragmentation features have previously been explored to infer gene expression profiles from cell-free DNA (cfDNA), but current fragmentomic methods require high concentrations of tumor-derived DNA and provide limited resolution. Here we describe promoter fragmentation entropy as an epigenomic cfDNA feature that predicts RNA expression levels at individual genes. We developed 'epigenetic expression inference from cell-free DNA-sequencing' (EPIC-seq), a method that uses targeted sequencing of promoters of genes of interest. Profiling 329 blood samples from 201 patients with cancer and 87 healthy adults, we demonstrate classification of subtypes of lung carcinoma and diffuse large B cell lymphoma. Applying EPIC-seq to serial blood samples from patients treated with PD-(L)1 immune-checkpoint inhibitors, we show that gene expression profiles inferred by EPIC-seq are correlated with clinical response. Our results indicate that EPIC-seq could enable noninvasive, high-throughput tissue-of-origin characterization with diagnostic, prognostic and therapeutic potential.

    View details for DOI 10.1038/s41587-022-01222-4

    View details for PubMedID 35361996

  • Enhanced detection of minimal residual disease by targeted sequencing of phased variants in circulating tumor DNA. Nature biotechnology Kurtz, D. M., Soo, J., Co Ting Keh, L., Alig, S., Chabon, J. J., Sworder, B. J., Schultz, A., Jin, M. C., Scherer, F., Garofalo, A., Macaulay, C. W., Hamilton, E. G., Chen, B., Olsen, M., Schroers-Martin, J. G., Craig, A. F., Moding, E. J., Esfahani, M. S., Liu, C. L., Duhrsen, U., Huttmann, A., Casasnovas, R., Westin, J. R., Roschewski, M., Wilson, W. H., Gaidano, G., Rossi, D., Diehn, M., Alizadeh, A. A. 2021


    Circulating tumor-derived DNA (ctDNA) is an emerging biomarker for many cancers, but the limited sensitivity of current detection methods reduces its utility for diagnosing minimal residual disease. Here we describe phased variant enrichment and detection sequencing (PhasED-seq), a method that uses multiple somatic mutations in individual DNA fragments to improve the sensitivity of ctDNA detection. Leveraging whole-genome sequences from 2,538 tumors, we identify phased variants and their associations with mutational signatures. We show that even without molecular barcodes, the limits of detection of PhasED-seq outperform prior methods, including duplex barcoding, allowing ctDNA detection in the ppm range in participant samples. We profiled 678 specimens from 213 participants with B cell lymphomas, including serial cell-free DNA samples before and during therapy for diffuse large B cell lymphoma. In participants with undetectable ctDNA after two cycles of therapy using a next-generation sequencing-based approach termed cancer personalized profiling by deep sequencing, an additional 25% have ctDNA detectable by PhasED-seq and have worse outcomes. Finally, we demonstrate the application of PhasED-seq to solid tumors.

    View details for DOI 10.1038/s41587-021-00981-w

    View details for PubMedID 34294911

  • The Ami and Yami aborigines of Taiwan and their genetic relationship to East Asian and Pacific populations. European journal of human genetics : EJHG Tatte, K., Metspalu, E., Post, H., Palencia-Madrid, L., Luis, J. R., Reidla, M., Rea, A., Tamm, E., Moding, E. J., de Pancorbo, M. M., Garcia-Bertrand, R., Metspalu, M., Herrera, R. J. 2021


    This article reports on the genetic characteristics of the Ami and Yami, two aboriginal populations of Taiwan. Y-SNP and mtDNA markers as well as autosomal SNPs were utilized to investigate the phylogenetic relationships to groups from MSEA (mainland Southeast Asia), ISEA (island Southeast Asia), and Oceania. Both the Ami and Yami have limited genetic diversity, with the Yami having even less diversity than the Ami. The partitioning of populations within the PCA plots based on autosomal SNPs, the profile constitution observed in the structure analyses demonstrating similar composition among specific populations, the average IBD (identical by descent) tract length gradients, the average total length of genome share among the populations, and the outgroup f3 results all indicate genetic affinities among populations that trace a geographical arc from Taiwan south into the Philippine Archipelago, Borneo, Indonesia, and Melanesia. Conversely, a more distant kinship between the Ami/Yami and MSEA based on all the markers examined, the total mtDNA sequences as well as the admixture f3 and f4 analyses argue against strong genetic contribution from MSEA to the Austronesian dispersal. The sharing of long IBD tracts, total genome length, and the large number of segments in common between the Ami/Yami and the Society Archipelago populations East Polynesia standout considering they are located about 10,700km apart.

    View details for DOI 10.1038/s41431-021-00837-6

    View details for PubMedID 33753914

  • Liquid Biopsies for Molecular Biology-Based Radiotherapy. International journal of molecular sciences Blomain, E. S., Moding, E. J. 2021; 22 (20)


    Molecular alterations drive cancer initiation and evolution during development and in response to therapy. Radiotherapy is one of the most commonly employed cancer treatment modalities, but radiobiologic approaches for personalizing therapy based on tumor biology and individual risks remain to be defined. In recent years, analysis of circulating nucleic acids has emerged as a non-invasive approach to leverage tumor molecular abnormalities as biomarkers of prognosis and treatment response. Here, we evaluate the roles of circulating tumor DNA and related analyses as powerful tools for precision radiotherapy. We highlight emerging work advancing liquid biopsies beyond biomarker studies into translational research investigating tumor clonal evolution and acquired resistance.

    View details for DOI 10.3390/ijms222011267

    View details for PubMedID 34681925

  • A mathematical model of ctDNA shedding predicts tumor detection size. Science advances Avanzini, S., Kurtz, D. M., Chabon, J. J., Moding, E. J., Hori, S. S., Gambhir, S. S., Alizadeh, A. A., Diehn, M., Reiter, J. G. 2020; 6 (50)


    Early cancer detection aims to find tumors before they progress to an incurable stage. To determine the potential of circulating tumor DNA (ctDNA) for cancer detection, we developed a mathematical model of tumor evolution and ctDNA shedding to predict the size at which tumors become detectable. From 176 patients with stage I to III lung cancer, we inferred that, on average, 0.014% of a tumor cell's DNA is shed into the bloodstream per cell death. For annual screening, the model predicts median detection sizes of 2.0 to 2.3 cm representing a ~40% decrease from the current median detection size of 3.5 cm. For informed monthly cancer relapse testing, the model predicts a median detection size of 0.83 cm and suggests that treatment failure can be detected 140 days earlier than with imaging-based approaches. This mechanistic framework can help accelerate clinical trials by precomputing the most promising cancer early detection strategies.

    View details for DOI 10.1126/sciadv.abc4308

    View details for PubMedID 33310847

  • A noninvasive approach for early prediction of therapeutic benefit from immune checkpoint inhibition for lung cancer Nabet, B. Y., Esfahani, M. S., Hamilton, E. G., Chabon, J. J., Moding, E. J., Rizvi, H., Steen, C. B., Chaudhuri, A. A., Liu, C., Hui, A. B., Stehr, H., Goljenola, L., Jin, M. C., Jeon, Y., Tseng, D., Merghoub, T., Neal, J. W., Wakelee, H. A., Padda, S. K., Ramchandran, K. J., Das, M., Bonilla, R. F., Yoo, C., Chen, E. L., Ko, R. B., Newman, A. M., Hellmann, M. D., Alizadeh, A. A., Diehn, M. AMER ASSOC CANCER RESEARCH. 2020
  • Chromatin accessibility patterns in cell-free DNA reveal tumor heterogeneity Esfahani, M., Mehrmohamadi, M., Steen, C. B., Hamilton, E. G., King, D. A., Soo, J., Macaulay, C., Jin, M., Kurtz, D. M., Nabet, B., Moding, E., Chabon, J., Newman, A., Diehn, M., Alizadeh, A. A. AMER ASSOC CANCER RESEARCH. 2020
  • Integrating genomic features for non-invasive early lung cancer detection. Nature Chabon, J. J., Hamilton, E. G., Kurtz, D. M., Esfahani, M. S., Moding, E. J., Stehr, H., Schroers-Martin, J., Nabet, B. Y., Chen, B., Chaudhuri, A. A., Liu, C. L., Hui, A. B., Jin, M. C., Azad, T. D., Almanza, D., Jeon, Y. J., Nesselbush, M. C., Co Ting Keh, L., Bonilla, R. F., Yoo, C. H., Ko, R. B., Chen, E. L., Merriott, D. J., Massion, P. P., Mansfield, A. S., Jen, J., Ren, H. Z., Lin, S. H., Costantino, C. L., Burr, R., Tibshirani, R., Gambhir, S. S., Berry, G. J., Jensen, K. C., West, R. B., Neal, J. W., Wakelee, H. A., Loo, B. W., Kunder, C. A., Leung, A. N., Lui, N. S., Berry, M. F., Shrager, J. B., Nair, V. S., Haber, D. A., Sequist, L. V., Alizadeh, A. A., Diehn, M. 2020; 580 (7802): 245-251


    Radiologic screening of high-risk adults reduces lung-cancer-related mortality1,2; however, a small minority of eligible individuals undergo such screening in the United States3,4. The availability of blood-based tests could increase screening uptake. Here we introduce improvements to cancer personalized profiling by deep sequencing (CAPP-Seq)5, a method for the analysis of circulating tumour DNA (ctDNA), to better facilitate screening applications. We show that, although levels are very low in early-stage lung cancers, ctDNA is present prior to treatment in most patients and its presence is strongly prognostic. We also find that the majority of somatic mutations in the cell-free DNA (cfDNA) of patients with lung cancer and of risk-matched controls reflect clonal haematopoiesis and are non-recurrent. Compared with tumour-derived mutations, clonal haematopoiesis mutations occur on longer cfDNA fragments and lack mutational signatures that are associated with tobacco smoking. Integrating these findings with other molecular features, we develop and prospectively validate a machine-learning method termed 'lung cancer likelihood in plasma' (Lung-CLiP), which can robustly discriminate early-stage lung cancer patients from risk-matched controls. This approach achieves performance similar to that of tumour-informed ctDNA detection and enables tuning of assay specificity in order to facilitate distinct clinical applications. Our findings establish the potential of cfDNA for lung cancer screening and highlight the importance of risk-matching cases and controls in cfDNA-based screening studies.

    View details for DOI 10.1038/s41586-020-2140-0

    View details for PubMedID 32269342

  • Noninvasive Early Identification of Therapeutic Benefit from Immune Checkpoint Inhibition. Cell Nabet, B. Y., Esfahani, M. S., Moding, E. J., Hamilton, E. G., Chabon, J. J., Rizvi, H. n., Steen, C. B., Chaudhuri, A. A., Liu, C. L., Hui, A. B., Almanza, D. n., Stehr, H. n., Gojenola, L. n., Bonilla, R. F., Jin, M. C., Jeon, Y. J., Tseng, D. n., Liu, C. n., Merghoub, T. n., Neal, J. W., Wakelee, H. A., Padda, S. K., Ramchandran, K. J., Das, M. n., Plodkowski, A. J., Yoo, C. n., Chen, E. L., Ko, R. B., Newman, A. M., Hellmann, M. D., Alizadeh, A. A., Diehn, M. n. 2020


    Although treatment of non-small cell lung cancer (NSCLC) with immune checkpoint inhibitors (ICIs) can produce remarkably durable responses, most patients develop early disease progression. Furthermore, initial response assessment by conventional imaging is often unable to identify which patients will achieve durable clinical benefit (DCB). Here, we demonstrate that pre-treatment circulating tumor DNA (ctDNA) and peripheral CD8 T cell levels are independently associated with DCB. We further show that ctDNA dynamics after a single infusion can aid in identification of patients who will achieve DCB. Integrating these determinants, we developed and validated an entirely noninvasive multiparameter assay (DIREct-On, Durable Immunotherapy Response Estimation by immune profiling and ctDNA-On-treatment) that robustly predicts which patients will achieve DCB with higher accuracy than any individual feature. Taken together, these results demonstrate that integrated ctDNA and circulating immune cell profiling can provide accurate, noninvasive, and early forecasting of ultimate outcomes for NSCLC patients receiving ICIs.

    View details for DOI 10.1016/j.cell.2020.09.001

    View details for PubMedID 33007267

  • Circulating tumor DNA analysis to assess risk of progression after long-term response to PD-(L)1 blockade in NSCLC. Clinical cancer research : an official journal of the American Association for Cancer Research Hellmann, M. D., Nabet, B. Y., Rizvi, H. n., Chaudhuri, A. A., Wells, D. K., Dunphy, M. P., Chabon, J. J., Liu, C. L., Hui, A. B., Arbour, K. C., Luo, J. n., Preeshagul, I. R., Moding, E. J., Almanza, D. n., Bonilla, R. F., Sauter, J. L., Choi, H. n., Tenet, M. n., Abu-Akeel, M. n., Plodkowski, A. J., Perez-Johnston, R. n., Yoo, C. H., Ko, R. B., Stehr, H. n., Gojenola, L. n., Wakelee, H. A., Padda, S. K., Neal, J. W., Chaft, J. E., Kris, M. G., Rudin, C. M., Merghoub, T. n., Li, B. T., Alizadeh, A. A., Diehn, M. n. 2020


    Treatment with PD-(L)1 blockade can produce remarkably durable responses in non-small cell lung cancer (NSCLC) patients. However, a significant fraction of long-term responders ultimately progress and predictors of late progression are unknown. We hypothesized that circulating tumor DNA (ctDNA) analysis of long-term responders to PD-(L)1 blockade may differentiate those who will achieve ongoing benefit from those at risk of eventual progression.In patients with advanced NSCLC achieving long-term benefit from PD-(L)1 blockade (PFS≥12 months), plasma was collected at a surveillance timepoint late during/after treatment to interrogate ctDNA by Cancer Personalized Profiling by Deep Sequencing (CAPP-Seq). Tumor tissue was available for 24 patients and was profiled by whole-exome sequencing (n=18) or by targeted sequencing (n=6).31 NSCLC patients with long-term benefit to PD-(L)1 blockade were identified and ctDNA was analyzed in surveillance blood samples collected at a median of 26.7 months after initiation of therapy. Nine patients also had baseline plasma samples available, and all had detectable ctDNA prior to therapy initiation. At the surveillance timepoint, 27 patients had undetectable ctDNA and 25 (93%) have remained progression-free; by contrast, all four patients with detectable ctDNA eventually progressed (Fisher's p<0.0001; PPV 1 [95% CI 0.51-1]; NPV 0.93 [95% CI 0.80-0.99]).ctDNA analysis can noninvasively identify minimal residual disease in patients with long-term responses to PD-(L)1 and predict the risk of eventual progression. If validated, ctDNA surveillance may facilitate personalization of the duration of immune checkpoint blockade and enable early intervention in patients at high risk for progression.

    View details for DOI 10.1158/1078-0432.CCR-19-3418

    View details for PubMedID 32046999

  • KEAP1/NFE2L2 mutations predict lung cancer radiation resistance that can be targeted by glutaminase inhibition. Cancer discovery Binkley, M. S., Jeon, Y. J., Nesselbush, M. n., Moding, E. J., Nabet, B. Y., Almanza, D. n., Kunder, C. n., Stehr, H. n., Yoo, C. H., Rhee, S. n., Xiang, M. n., Chabon, J. J., Hamilton, E. n., Kurtz, D. M., Gojenola, L. n., Owen, S. G., Ko, R. B., Shin, J. H., Maxim, P. G., Lui, N. S., Backhus, L. M., Berry, M. F., Shrager, J. B., Ramchandran, K. J., Padda, S. K., Das, M. n., Neal, J. W., Wakelee, H. A., Alizadeh, A. A., Loo, B. W., Diehn, M. n. 2020


    Tumor genotyping is not routinely performed in localized non-small cell lung cancer (NSCLC) due to lack of associations of mutations with outcome. Here, we analyze 232 consecutive patients with localized NSCLC and demonstrate that KEAP1 and NFE2L2 mutations are predictive of high rates of local recurrence (LR) after radiotherapy but not surgery. Half of LRs occurred in KEAP1/NFE2L2 mutation tumors, indicating they are major molecular drivers of clinical radioresistance. Next, we functionally evaluate KEAP1/NFE2L2 mutations in our radiotherapy cohort and demonstrate that only pathogenic mutations are associated with radioresistance. Furthermore, expression of NFE2L2 target genes does not predict LR, underscoring the utility of tumor genotyping. Finally, we show that glutaminase inhibition preferentially radiosensitizes KEAP1 mutant cells via depletion of glutathione and increased radiation-induced DNA damage. Our findings suggest that genotyping for KEAP1/NFE2L2 mutations could facilitate treatment personalization and provide a potential strategy for overcoming radioresistance conferred by these mutations.

    View details for DOI 10.1158/2159-8290.CD-20-0282

    View details for PubMedID 33071215

  • Predictors of Respiratory Decline Following Stereotactic Ablative Radiotherapy to Multiple Lung Tumors. Clinical lung cancer Moding, E. J., Liang, R. n., Lartey, F. M., Maxim, P. G., Sung, A. n., Diehn, M. n., Loo, B. W., Gensheimer, M. F. 2019


    Stereotactic ablative radiotherapy (SABR) is highly effective at controlling early stage primary lung cancer and lung metastases. Although previous studies have suggested that treating multiple lung tumors with SABR is safe, post-treatment changes in respiratory function have not been analyzed in detail.We retrospectively identified patients with 2 or more primary lung cancers or lung metastases treated with SABR and analyzed clinical outcomes and predictors of toxicity. We defined a composite respiratory decline endpoint to include increased oxygen requirement, increased dyspnea scale, or death from respiratory failure not owing to disease progression.A total of 86 patients treated with SABR to 203 lung tumors were analyzed. A total of 21.8% and 41.8% of patients developed composite respiratory decline at 2 and 4 years, respectively. When accounting for intrathoracic disease progression, 12.7% of patients developed composite respiratory decline at 2 years. Of the patients, 7.9% experienced grade 2 or greater radiation pneumonitis. No patient- or treatment-related factor predicted development of respiratory decline. The median overall survival was 46.9 months, and the median progression-free survival was 14.8 months. The cumulative incidence of local failure was 9.7% at 2 years.Although our results confirm that SABR is an effective treatment modality for patients with multiple lung tumors, we observed a high rate of respiratory decline after treatment, which may be owing to a combination of treatment and disease effects. Future studies may help to determine ways to avoid pulmonary toxicity from SABR.

    View details for DOI 10.1016/j.cllc.2019.05.015

    View details for PubMedID 31377143

  • Prognostic factors and patterns of failure in advanced stage Hodgkin lymphoma treated with combined modality therapy. Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology Moding, E. J., Advani, R., Rosenberg, S. A., Hoppe, R. T. 2018; 129 (3): 507–12


    BACKGROUND AND PURPOSE: The role of irradiation to non-bulky and bulky sites of disease in advanced stage Hodgkin lymphoma is controversial. We aimed to review the long-term outcomes of patients treated with combined modality therapy to clarify the role of consolidative radiotherapy.MATERIALS AND METHODS: Patients with stage III or IV Hodgkin lymphoma treated with Stanford V chemotherapy and consolidative radiotherapy to initial sites of disease ≥5 cm were analyzed retrospectively to determine patient outcomes, patterns of failure, and factors associated with treatment failure.RESULTS: A total of 170 patients were analyzed. Overall survival was 91.2%, freedom from progression was 80.6%, and progression-free survival was 78.9% at 10 years. 5 patients (2.9%) had refractory disease and 27 patients (15.9%) relapsed after treatment. Only an International Prognostic Score (IPS) greater than 2 predicted disease progression. 19 out of 27 relapses occurred exclusively outside of the radiation treatment field, and 17 out of 27 relapses occurred exclusively at original sites of disease. However, only 11 of 170 patients (6.5%) relapsed exclusively at original, non-bulky sites of disease not treated with radiation therapy. The cumulative incidence of local failure at 10 years was 4.6% for unirradiated sites and 2.6% for irradiated sites.CONCLUSION: Patients with advanced stage Hodgkin lymphoma treated with combined modality therapy including consolidative radiotherapy to bulky disease sites had excellent long-term outcomes. Given the low frequency of isolated failures at initial sites, our results suggest that selective radiation therapy to sites at high risk of relapse may be feasible.

    View details for PubMedID 30539763

  • Notch-Induced Myeloid Reprogramming in Spontaneous Pancreatic Ductal Adenocarcinoma by Dual Genetic Targeting CANCER RESEARCH Cheung, P. F., Neff, F., Neander, C., Bazarna, A., Savvatakis, K., Liffers, S., Althoff, K., Lee, C., Moding, E. J., Kirsch, D. G., Saur, D., Bazhin, A. V., Trajkovic-Arsic, M., Heikenwalder, M. F., Siveke, J. T. 2018; 78 (17): 4997–5010


    Despite advances in our understanding of the genetics of pancreatic ductal adenocarcinoma (PDAC), the efficacy of therapeutic regimens targeting aberrant signaling pathways remains highly limited. Therapeutic strategies are greatly hampered by the extensive desmoplasia that comprises heterogeneous cell populations. Notch signaling is a contentious pathway exerting opposite roles in tumorigenesis depending on cellular context. Advanced model systems are needed to gain more insights into complex signaling in the multilayered tumor microenvironment. In this study, we employed a dual recombinase-based in vivo strategy to modulate Notch signaling specifically in myeloid cells to dissect the tumorigenic role of Notch in PDAC stroma. Pancreas-specific KrasG12D activation and loss of Tp53 was induced using a Pdx1-Flp transgene, whereas Notch signaling was genetically targeted using a myeloid-targeting Lyz2-Cre strain for either activation of Notch2-IC or deletion of Rbpj. Myeloid-specific Notch activation significantly decreased tumor infiltration by protumorigenic M2 macrophages in spontaneous endogenous PDAC, which translated into significant survival benefit. Further characterization revealed upregulated antigen presentation and cytotoxic T effector phenotype upon Notch-induced M2 reduction. This approach is the first proof of concept for genetic targeting and reprogramming of myeloid cells in a complex disease model of PDAC and provides evidence for a regulatory role of Notch signaling in intratumoral immune phenotypes.Significance: This study provides insight into the role of myeloid-dependent NOTCH signaling in PDAC and accentuates the need to dissect differential roles of signaling pathways in different cellular components within the tumor microenvironment. Cancer Res; 78(17); 4997-5010. ©2018 AACR.

    View details for PubMedID 29844119

  • Mice Lacking RIP3 Kinase are not Protected from Acute Radiation Syndrome RADIATION RESEARCH Castle, K. D., Daniel, A. R., Moding, E. J., Luo, L., Lee, C., Kirsch, D. G. 2018; 189 (6): 627–33


    Exposure to high doses of ionizing radiation can cause lethal injury to normal tissue, thus inducing acute radiation syndrome. Acute radiation syndrome is caused by depletion of bone marrow cells (hematopoietic syndrome) and irreparable damage to the epithelial cells in the gastrointestinal tract (gastrointestinal syndrome). Although radiation initiates apoptosis in the hematopoietic and gastrointestinal compartments within the first few hours after exposure, alternative mechanisms of cell death may contribute to injury in these radiosensitive tissues. In this study, we utilized mice lacking a critical regulator of necroptosis, receptor interacting protein 3 (RIP3) kinase, to characterize the role of RIP3 in normal tissue toxicity after irradiation. Our results suggest that RIP3-mediated signaling is not a critical driver of acute radiation syndrome.

    View details for PubMedID 29634408

    View details for PubMedCentralID PMC6020684

  • Circulating tumor DNA testing in advanced non-small cell lung cancer. Lung cancer (Amsterdam, Netherlands) Moding, E. J., Diehn, M., Wakelee, H. A. 2018; 119: 42–47


    Circulating tumor DNA (ctDNA) shed from cancer cells into the peripheral blood can be non-invasively collected and tested for the presence of tumor-specific mutations. Mutations identified in ctDNA can predict responses to targeted therapies and emerging evidence suggests that changes in ctDNA levels over time can be used to monitor response to therapy and detect disease recurrence. Given the emergence of targeted therapies in advanced non-small cell lung cancer (NSCLC), liquid biopsies utilizing ctDNA testing represent a powerful approach to genotype tumors and monitor for the development of resistance. Here, we review current and potential future clinical applications of ctDNA testing for patients with advanced NSCLC.

    View details for PubMedID 29656751

  • Survival Impact of Postoperative Radiotherapy Timing in Pediatric and Adolescent Medulloblastoma. Neuro-oncology Chin, A. L., Moding, E. J., Donaldson, S. S., Gibbs, I. C., Soltys, S. G., Hiniker, S. M., Pollom, E. L. 2018


    Radiation therapy (RT) remains a critical component of multimodality treatment for medulloblastoma. Traditionally, clinicians strive to start RT within 4-5 weeks of surgery, but the optimal timing after surgery remains unclear.Using the National Cancer Database, we identified pediatric and adolescent patients with medulloblastoma treated with curative-intent surgery, RT, and chemotherapy. Factors associated with early or delayed RT were identified using Pearson chi-squared tests. Overall survival (OS) differences based on RT timing were compared using the Kaplan-Meier estimator with log-rank tests. Patient, tumor, and treatment characteristics associated with OS were analyzed with univariate and multivariate Cox proportional hazard models.Among the 1338 patients analyzed, early RT (defined as initiation ≤3 weeks after surgery) was associated with younger age, M1-3 disease, and subtotal resection. Patients who initiated RT early had decreased five-year OS compared with patients who initiated RT 3.1-4, 4.1-5, or >5 weeks after surgery (72.5%, 80.5%, 79.4%, and 77.8%, respectively; p=0.019), but there was no significant difference in OS among the latter three groups (p=0.788). On multivariate analysis, early RT versus the 3.1-4-week interval was significantly associated with poorer OS (adjusted HR 1.72; 95% CI 1.19-2.48; p=0.004), while time to RT of >5 weeks but within 90 days of surgery did not adversely impact OS (p=0.563).In this large national database analysis, delaying RT within 90 days of surgery was not associated with inferior outcomes. Although clinical judgment remains paramount, postoperative RT timing should allow for healing and the development of an optimal treatment plan.

    View details for PubMedID 29309676

  • The Impact of Post-Operative Therapy on Primary Cardiac Sarcoma The Journal of Thoracic and Cardiovascular Surgery Wu, Y., Million, L., Moding, E. J., Scott, G., Berry, M., Ganjoo, K. N. 2018
  • Concurrent Imatinib and Radiation Therapy for Unresectable and Symptomatic Desmoid Tumors. Sarcoma Moding, E. J., Million, L., Avedian, R., Ghanouni, P., Kunder, C., Ganjoo, K. N. 2017; 2017: 2316839


    Desmoid tumors are locally aggressive fibroproliferative neoplasms that can lead to pain and dysfunction due to compression of nerves and surrounding structures. Desmoid tumors often progress through medical therapy, and there is frequently a delay of multiple months before radiation can provide symptomatic relief. To achieve more rapid symptomatic relief and tumor regression for unresectable desmoid tumors causing significant morbidity such as brachial plexus impingement with loss of extremity function, we have selectively utilized a combination of imatinib and radiation therapy. Here, we retrospectively review four patients treated with concurrent imatinib and radiation therapy. The treatment was typically tolerated with minimal toxicity though one patient developed avascular necrosis of the irradiated humeral head possibly related to the combined treatment. All the patients treated have had a partial response or stable disease on imaging. Improvement of symptoms was observed in all the treated patients with a median time to relief of 2.5 months after starting radiation therapy. Concurrent radiation and imatinib may represent a viable treatment option for unresectable and symptomatic desmoid tumors where rapid relief is needed to prevent permanent loss of function.

    View details for PubMedID 28761389

  • An extra copy of p53 suppresses development of spontaneous Kras-driven but not radiation-induced cancer JCI INSIGHT Moding, E. J., Min, H. D., Castle, K. D., Ali, M., Woodlief, L., Williams, N., Ma, Y., Kim, Y., Lee, C., Kirsch, D. G. 2016; 1 (10)
  • Opportunities for Radiosensitization in the Stereotactic Body Radiation Therapy (SBRT) Era CANCER JOURNAL Moding, E. J., Mowery, Y. M., Kirsch, D. G. 2016; 22 (4): 267–73


    Stereotactic body radiation therapy (SBRT) utilizing a small number of high-dose radiation therapy fractions continues to expand in clinical application. Although many approaches have been proposed to radiosensitize tumors with conventional fractionation, how these radiosensitizers will translate to SBRT remains largely unknown. Here, we review our current understanding of how SBRT eradicates tumors, including the potential contributions of endothelial cell death and immune system activation. In addition, we identify several new opportunities for radiosensitization generated by the move toward high dose per fraction radiation therapy.

    View details for PubMedID 27441746

    View details for PubMedCentralID PMC4957656

  • A dual energy CT study on vascular effects of gold nanoparticles in radiation therapy Ashton, J. R., Hoye, J., Deland, K., Whitley, M., Qi, Y., Moding, E., Kirsch, D. G., West, J., Badea, C. T., Gimi, B., Krol, A. SPIE-INT SOC OPTICAL ENGINEERING. 2016

    View details for DOI 10.1117/12.2217012

    View details for Web of Science ID 000378223800028

  • Acute DNA damage activates the tumour suppressor p53 to promote radiation-induced lymphoma NATURE COMMUNICATIONS Lee, C., Castle, K. D., Moding, E. J., Blum, J. M., Williams, N., Luo, L., Ma, Y., Borst, L. B., Kim, Y., Kirsch, D. G. 2015; 6: 8477


    Genotoxic cancer therapies, such as chemoradiation, cause haematological toxicity primarily by activating the tumour suppressor p53. While inhibiting p53-mediated cell death during cancer therapy ameliorates haematologic toxicity, whether it also impacts carcinogenesis remains unclear. Here we utilize a mouse model of inducible p53 short hairpin RNA (shRNA) to show that temporarily blocking p53 during total-body irradiation (TBI) not only ameliorates acute toxicity, but also improves long-term survival by preventing lymphoma development. Using Kras(LA1) mice, we show that TBI promotes the expansion of a rare population of thymocytes that express oncogenic Kras(G12D). However, blocking p53 during TBI significantly suppresses the expansion of Kras(G12D)-expressing thymocytes. Mechanistically, bone marrow transplant experiments demonstrate that TBI activates p53 to decrease the ability of bone marrow cells to suppress lymphoma development through a non-cell-autonomous mechanism. Together, our results demonstrate that the p53 response to acute DNA damage promotes the development of radiation-induced lymphoma.

    View details for PubMedID 26399548

  • A Plasmonic Gold Nanostar Theranostic Probe for In Vivo Tumor Imaging and Photothermal Therapy THERANOSTICS Liu, Y., Ashton, J. R., Moding, E. J., Yuan, H., Register, J. K., Fales, A. M., Choi, J., Whitley, M. J., Zhao, X., Qi, Y., Ma, Y., Vaidyanathan, G., Zalutsky, M. R., Kirsch, D. G., Badea, C. T., Vo-Dinh, T. 2015; 5 (9): 946–60


    Nanomedicine has attracted increasing attention in recent years, because it offers great promise to provide personalized diagnostics and therapy with improved treatment efficacy and specificity. In this study, we developed a gold nanostar (GNS) probe for multi-modality theranostics including surface-enhanced Raman scattering (SERS) detection, x-ray computed tomography (CT), two-photon luminescence (TPL) imaging, and photothermal therapy (PTT). We performed radiolabeling, as well as CT and optical imaging, to investigate the GNS probe's biodistribution and intratumoral uptake at both macroscopic and microscopic scales. We also characterized the performance of the GNS nanoprobe for in vitro photothermal heating and in vivo photothermal ablation of primary sarcomas in mice. The results showed that 30-nm GNS have higher tumor uptake, as well as deeper penetration into tumor interstitial space compared to 60-nm GNS. In addition, we found that a higher injection dose of GNS can increase the percentage of tumor uptake. We also demonstrated the GNS probe's superior photothermal conversion efficiency with a highly concentrated heating effect due to a tip-enhanced plasmonic effect. In vivo photothermal therapy with a near-infrared (NIR) laser under the maximum permissible exposure (MPE) led to ablation of aggressive tumors containing GNS, but had no effect in the absence of GNS. This multifunctional GNS probe has the potential to be used for in vivo biosensing, preoperative CT imaging, intraoperative detection with optical methods (SERS and TPL), as well as image-guided photothermal therapy.

    View details for PubMedID 26155311

  • A next-generation dual-recombinase system for time- and host-specific targeting of pancreatic cancer NATURE MEDICINE Schoenhuber, N., Seidler, B., Schuck, K., Veltkamp, C., Schachtler, C., Zukowska, M., Eser, S., Feyerabend, T. B., Paul, M. C., Eser, P., Klein, S., Lowy, A. M., Banerjee, R., Yang, F., Lee, C., Moding, E. J., Kirsch, D. G., Scheideler, A., Alessi, D. R., Varela, I., Bradley, A., Kind, A., Schnieke, A. E., Rodewald, H., Rad, R., Schmid, R. M., Schneider', G., Saur, D. 2014; 20 (11): 1340–47


    Genetically engineered mouse models (GEMMs) have dramatically improved our understanding of tumor evolution and therapeutic resistance. However, sequential genetic manipulation of gene expression and targeting of the host is almost impossible using conventional Cre-loxP-based models. We have developed an inducible dual-recombinase system by combining flippase-FRT (Flp-FRT) and Cre-loxP recombination technologies to improve GEMMs of pancreatic cancer. This enables investigation of multistep carcinogenesis, genetic manipulation of tumor subpopulations (such as cancer stem cells), selective targeting of the tumor microenvironment and genetic validation of therapeutic targets in autochthonous tumors on a genome-wide scale. As a proof of concept, we performed tumor cell-autonomous and nonautonomous targeting, recapitulated hallmarks of human multistep carcinogenesis, validated genetic therapy by 3-phosphoinositide-dependent protein kinase inactivation as well as cancer cell depletion and show that mast cells in the tumor microenvironment, which had been thought to be key oncogenic players, are dispensable for tumor formation.

    View details for PubMedID 25326799

    View details for PubMedCentralID PMC4270133

  • Reining in Radiation Injury: HIF2 alpha in the Gut SCIENCE TRANSLATIONAL MEDICINE Lee, C., Moding, E. J., Kirsch, D. G. 2014; 6 (236): 236fs20


    Deletion of prolyl hydroxylase domain proteins or overexpression of hypoxia-inducible factor 2α (HIF2α) in the gastrointestinal epithelium improves survival of mice after abdominal irradiation (Taniguchi et al., this issue).

    View details for PubMedID 24828075

  • Dual-Energy Micro-CT Functional Imaging of Primary Lung Cancer in Mice Using Gold and Iodine Nanoparticle Contrast Agents: A Validation Study PLOS ONE Ashton, J. R., Clark, D. P., Moding, E. J., Ghaghada, K., Kirsch, D. G., West, J. L., Badea, C. T. 2014; 9 (2): e88129


    To provide additional functional information for tumor characterization, we investigated the use of dual-energy computed tomography for imaging murine lung tumors. Tumor blood volume and vascular permeability were quantified using gold and iodine nanoparticles. This approach was compared with a single contrast agent/single-energy CT method. Ex vivo validation studies were performed to demonstrate the accuracy of in vivo contrast agent quantification by CT.Primary lung tumors were generated in LSL-Kras(G12D); p53(FL/FL) mice. Gold nanoparticles were injected, followed by iodine nanoparticles two days later. The gold accumulated in tumors, while the iodine provided intravascular contrast. Three dual-energy CT scans were performed-two for the single contrast agent method and one for the dual contrast agent method. Gold and iodine concentrations in each scan were calculated using a dual-energy decomposition. For each method, the tumor fractional blood volume was calculated based on iodine concentration, and tumor vascular permeability was estimated based on accumulated gold concentration. For validation, the CT-derived measurements were compared with histology and inductively-coupled plasma optical emission spectroscopy measurements of gold concentrations in tissues.Dual-energy CT enabled in vivo separation of gold and iodine contrast agents and showed uptake of gold nanoparticles in the spleen, liver, and tumors. The tumor fractional blood volume measurements determined from the two imaging methods were in agreement, and a high correlation (R(2) = 0.81) was found between measured fractional blood volume and histology-derived microvascular density. Vascular permeability measurements obtained from the two imaging methods agreed well with ex vivo measurements.Dual-energy CT using two types of nanoparticles is equivalent to the single nanoparticle method, but allows for measurement of fractional blood volume and permeability with a single scan. As confirmed by ex vivo methods, CT-derived nanoparticle concentrations are accurate. This method could play an important role in lung tumor characterization by CT.

    View details for PubMedID 24520351

  • Dual-Energy Micro-Computed Tomography Imaging of Radiation-Induced Vascular Changes in Primary Mouse Sarcomas INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS Moding, E. J., Clark, D. P., Qi, Y., Li, Y., Ma, Y., Ghaghada, K., Johnson, G., Kirsch, D. G., Badea, C. T. 2013; 85 (5): 1353–59


    To evaluate the effects of radiation therapy on primary tumor vasculature using dual-energy (DE) micro-computed tomography (micro-CT).Primary sarcomas were generated with mutant Kras and p53. Unirradiated tumors were compared with tumors irradiated with 20 Gy. A liposomal-iodinated contrast agent was administered 1 day after treatment, and mice were imaged immediately after injection (day 1) and 3 days later (day 4) with DE micro-CT. CT-derived tumor sizes were used to assess tumor growth. After DE decomposition, iodine maps were used to assess tumor fractional blood volume (FBV) at day 1 and tumor vascular permeability at day 4. For comparison, tumor vascularity and vascular permeability were also evaluated histologically by use of CD31 immunofluorescence and fluorescently-labeled dextrans.Radiation treatment significantly decreased tumor growth from day 1 to day 4 (P<.05). There was a positive correlation between CT measurement of tumor FBV on day 1 and extravasated iodine on day 4 with microvascular density (MVD) on day 4 (R(2)=0.53) and dextran accumulation (R(2)=0.63) on day 4, respectively. Despite no change in MVD measured by histology, tumor FBV significantly increased after irradiation as measured by DE micro-CT (0.070 vs 0.091, P<.05). Both dextran and liposomal-iodine accumulation in tumors increased significantly after irradiation, with dextran fractional area increasing 5.2-fold and liposomal-iodine concentration increasing 4.0-fold.DE micro-CT is an effective tool for noninvasive assessment of vascular changes in primary tumors. Tumor blood volume and vascular permeability increased after a single therapeutic dose of radiation treatment.

    View details for PubMedID 23122984

  • In vivo characterization of tumor vasculature using iodine and gold nanoparticles and dual energy micro-CT PHYSICS IN MEDICINE AND BIOLOGY Clark, D. P., Ghaghada, K., Moding, E. J., Kirsch, D. G., Badea, C. T. 2013; 58 (6): 1683–1704


    Tumor blood volume and vascular permeability are well established indicators of tumor angiogenesis and important predictors in cancer diagnosis, planning and treatment. In this work, we establish a novel preclinical imaging protocol which allows quantitative measurement of both metrics simultaneously. First, gold nanoparticles are injected and allowed to extravasate into the tumor, and then liposomal iodine nanoparticles are injected. Combining a previously optimized dual energy micro-CT scan using high-flux polychromatic x-ray sources (energies: 40 kVp, 80 kVp) with a novel post-reconstruction spectral filtration scheme, we are able to decompose the results into 3D iodine and gold maps, allowing simultaneous measurement of extravasated gold and intravascular iodine concentrations. Using a digital resolution phantom, the mean limits of detectability (mean CNR = 5) for each element are determined to be 2.3 mg mL(-1) (18 mM) for iodine and 1.0 mg mL(-1) (5.1 mM) for gold, well within the observed in vivo concentrations of each element (I: 0-24 mg mL(-1), Au: 0-9 mg mL(-1)) and a factor of 10 improvement over the limits without post-reconstruction spectral filtration. Using a calibration phantom, these limits are validated and an optimal sensitivity matrix for performing decomposition using our micro-CT system is derived. Finally, using a primary mouse model of soft-tissue sarcoma, we demonstrate the in vivo application of the protocol to measure fractional blood volume and vascular permeability over the course of five days of active tumor growth.

    View details for PubMedID 23422321

  • A comparison of radial keyhole strategies for high spatial and temporal resolution 4D contrast-enhanced MRI in small animal tumor models MEDICAL PHYSICS Subashi, E., Moding, E. J., Cofer, G. P., MacFall, J. R., Kirsch, D. G., Qi, Y., Johnson, G. 2013; 40 (2): 022304


    Dynamic contrast-enhanced (DCE) MRI has been widely used as a quantitative imaging method for monitoring tumor response to therapy. The simultaneous challenges of increasing temporal and spatial resolution in a setting where the signal from the much smaller voxel is weaker have made this MR technique difficult to implement in small-animal imaging. Existing protocols employed in preclinical DCE-MRI acquire a limited number of slices resulting in potentially lost information in the third dimension. This study describes and compares a family of four-dimensional (3D spatial + time), projection acquisition, radial keyhole-sampling strategies that support high spatial and temporal resolution.The 4D method is based on a RF-spoiled, steady-state, gradient-recalled sequence with minimal echo time. An interleaved 3D radial trajectory with a quasi-uniform distribution of points in k-space was used for sampling temporally resolved datasets. These volumes were reconstructed with three different k-space filters encompassing a range of possible radial keyhole strategies. The effect of k-space filtering on spatial and temporal resolution was studied in a 5 mM CuSO(4) phantom consisting of a meshgrid with 350-μm spacing and in 12 tumors from three cell lines (HT-29, LoVo, MX-1) and a primary mouse sarcoma model (three tumors∕group). The time-to-peak signal intensity was used to assess the effect of the reconstruction filters on temporal resolution. As a measure of heterogeneity in the third dimension, the authors analyzed the spatial distribution of the rate of transport (K(trans)) of the contrast agent across the endothelium barrier for several different types of tumors.Four-dimensional radial keyhole imaging does not degrade the system spatial resolution. Phantom studies indicate there is a maximum 40% decrease in signal-to-noise ratio as compared to a fully sampled dataset. T1 measurements obtained with the interleaved radial technique do not differ significantly from those made with a conventional Cartesian spin-echo sequence. A bin-by-bin comparison of the distribution of the time-to-peak parameter shows that 4D radial keyhole reconstruction does not cause significant temporal blurring when a temporal resolution of 9.9 s is used for the subsamples of the keyhole data. In vivo studies reveal substantial tumor heterogeneity in the third spatial dimension that may be missed with lower resolution imaging protocols.Volumetric keyhole imaging with projection acquisition provides a means to increase spatiotemporal resolution and coverage over that provided by existing 2D Cartesian protocols. Furthermore, there is no difference in temporal resolution between the higher spatial resolution keyhole reconstruction and the undersampled projection data. The technique allows one to measure complex heterogeneity of kinetic parameters with isotropic, microscopic spatial resolution.

    View details for PubMedID 23387766

  • p53 Functions in Endothelial Cells to Prevent Radiation-Induced Myocardial Injury in Mice SCIENCE SIGNALING Lee, C., Moding, E. J., Cuneo, K. C., Li, Y., Sullivan, J. M., Mao, L., Washington, I., Jeffords, L. B., Rodrigues, R. C., Ma, Y., Das, S., Kontos, C. D., Kim, Y., Rockman, H. A., Kirsch, D. G. 2012; 5 (234): ra52


    Radiation therapy, which is used for the treatment of some cancers, can cause delayed heart damage. In the heart, p53 influences myocardial injury that occurs after multiple types of stress. Here, we demonstrated that p53 functioned in endothelial cells to protect mice from myocardial injury after whole-heart irradiation. Mice with an endothelial cell-specific deletion of p53 succumbed to heart failure after whole-heart irradiation as a result of myocardial necrosis, systolic dysfunction, and cardiac hypertrophy. Moreover, the onset of cardiac dysfunction was preceded by alterations in myocardial vascular permeability and density, which resulted in cardiac ischemia and myocardial hypoxia. Mechanistic studies with primary cardiac endothelial cells irradiated in vitro indicated that p53 signaling caused mitotic arrest and protected cardiac endothelial cells from cell death resulting from abnormal mitosis or mitotic catastrophe. Furthermore, mice lacking the cyclin-dependent kinase inhibitor p21, which is a transcriptional target of p53, were also sensitized to myocardial injury after whole-heart irradiation. Together, our results demonstrate that the p53-p21 axis functions to prevent radiation-induced myocardial injury in mice.

    View details for PubMedID 22827996

  • Generation of primary tumors with Flp recombinase in FRT-flanked p53 mice DISEASE MODELS & MECHANISMS Lee, C., Moding, E. J., Huang, X., Li, Y., Woodlief, L. Z., Rodrigues, R. C., Ma, Y., Kirsch, D. G. 2012; 5 (3): 397–402


    The site-specific recombinases Cre and Flp can mutate genes in a spatially and temporally restricted manner in mice. Conditional recombination of the tumor suppressor gene p53 using the Cre-loxP system has led to the development of multiple genetically engineered mouse models of human cancer. However, the use of Cre recombinase to initiate tumors in mouse models limits the utilization of Cre to genetically modify other genes in tumor stromal cells in these models. To overcome this limitation, we inserted FRT (flippase recognition target) sites flanking exons 2-6 of the endogenous p53 gene in mice to generate a p53(FRT) allele that can be deleted by Flp recombinase. We show that FlpO-mediated deletion of p53 in mouse embryonic fibroblasts impairs the p53-dependent response to genotoxic stress in vitro. In addition, using FSF-Kras(G12D/+); p53(FRT/FRT) mice, we demonstrate that an adenovirus expressing FlpO recombinase can initiate primary lung cancers and sarcomas in mice. p53(FRT) mice will enable dual recombinase technology to study cancer biology because Cre is available to modify genes specifically in stromal cells to investigate their role in tumor development, progression and response to therapy.

    View details for PubMedID 22228755

  • p53 acts during total-body irradiation to promote lymphomagenesis Lee, C., Bium, J. M., Moding, E. J., Sullivan, J. M., Jeffords, L. B., Rodrigues, R. C., Ma, Y., Kim, Y., Kirsch, D. G. AMER ASSOC CANCER RESEARCH. 2012