With an interdisciplinary background of nano-science and biotechnology, my research interest lies in exploring nano-enabled approaches for targeted delivery of microRNA therapeutics and suicide genes to cancer cells (Hepatocarcinoma or Glioblastoma). Synonymous to the quote "seeing is believing", I go a step further to combine these therapeutic approaches with diagnostic nano-materials (hybrid metal/metal oxide nano-particles and carbon dots) and dyes to track and image spatio-temporal therapeutic response of tumor. In short, formulation and assessment of theragonostic nano-material is the crux of my research.
Doctor of Philosophy, Indian Institute of Technology, Roorkee (2017)
Master of Technology, Indian Institute of Technology, Roorkee (2012)
Bachelor of Technology, Anna University (2010)
Ramasamy Paulmurugan, Postdoctoral Faculty Sponsor
Intranasal delivery of targeted polyfunctional gold-iron oxide nanoparticles loaded with therapeutic microRNAs for combined theranostic multimodality imaging and presensitization of glioblastoma to temozolomide.
2019; 218: 119342
The prognosis for glioblastoma (GBM) remains depressingly low. The biological barriers of the brain present a major challenge to achieving adequate drug concentrations for GBM therapy. To address this, we explore the potential of the nose-to-brain direct transport pathway to bypass the blood-brain barrier, and to enable targeted delivery of theranostic polyfunctional gold-iron oxide nanoparticles (polyGIONs) surface loaded with therapeutic miRNAs (miR-100 and antimiR-21) to GBMs in mice. These nanoformulations would thus allow presensitization of GBM cells to the systemically delivered chemotherapy drug temozolomide (TMZ), as well as in vivo multimodality molecular and anatomic imaging of nanoparticle delivery, trafficking, and treatment effects. First, we synthesized GIONs coated with beta-cyclodextrin-chitosan (CD-CS) hybrid polymer, and co-loaded with miR-100 and antimiR-21. Then we decorated their surface with PEG-T7 peptide using CD-adamantane host-guest chemistry. The resultant polyGIONs showed efficient miRNA loading with enhanced serum stability. We characterized them for particle size, PDI, polymer functionalization, charge and release using dynamic light scattering analysis, TEM and qRT-PCR. For in vivo intranasal delivery, we used U87-MG GBM cell-derived orthotopic xenograft models in mice. Intranasal delivery resulted in efficient accumulation of Cy5-miRNAs in mice treated with T7-targeted polyGIONs, as demonstrated by in vivo optical fluorescence and MR imaging. We measured the therapeutic response of these FLUC-EGFP labelled U87-MG GBMs using bioluminescence imaging. Overall, there was a significant increase in survival of mice co-treated with T7-polyGIONs loaded with miR-100/antimiR-21 plus systemic TMZ, compared to the untreated control group, or the animals receiving non-targeted polyGIONs-miR-100/antimiR-21, or TMZ alone. Once translated clinically, this novel theranostic nanoformulation and its associated intranasal delivery strategy will have a strong potential to potentiate the effects of TMZ treatment in GBM patients.
View details for DOI 10.1016/j.biomaterials.2019.119342
View details for PubMedID 31326657
Tumor Cell-Derived Extracellular Vesicle-Coated Nanocarriers: An Efficient Theranostic Platform for the Cancer-Specific Delivery of Anti-miR-21 and Imaging Agents.
MicroRNAs are critical regulators of cancer initiation, progression, and dissemination. Extensive evidence suggests that the inhibition of over-expressed oncogenic miRNA function can be a robust strategy for anticancer therapy. However, in vivo targeted delivery of miRNA therapeutics to various types of cancers remains a major challenge. Inspired by their natural synthesis and cargo delivery capabilities, researchers have exploited tumor cell-derived extracellular vesicles (TEVs) for the cancer-targeted delivery of therapeutics and theranostics. Here, we investigate a TEV-based nanoplatform for multimodal miRNA delivery and phototherapy treatments as well as the magnetic resonance imaging of cancer. We demonstrated loading of anti-miR-21 that blocks the function of endogenous oncogenic miR-21 over-expressed in cancer cells into and subsequent delivery by TEVs derived from 4T1 cells. We also produced Cy5-anti-miR-21-loaded TEVs from two other cancer cell lines (HepG2 and SKBR3) and confirmed their robust homologous and heterologous transfection efficiency and intracellular Cy5-anti-miR-21 delivery. Additionally, TEV-mediated anti-miR-21 delivery attenuated doxorubicin (DOX) resistance in breast cancer cells with a 3-fold higher cell kill efficiency than in cells treated with DOX alone. We then investigated TEVs as a biomimetic source for the functionalization of gold-iron oxide nanoparticles (GIONs) and demonstrated nanotheranostic properties of TEV-GIONs in vitro. TEV-GIONs demonstrated excellent T2 contrast in in vitro magnetic resonance (MR) imaging and resulted in efficient photothermal effect in 4T1 cells. We also evaluated the biodistribution and theranostic property of anti-miR-21 loaded TEV-GIONs in vivo by labeling with indocyanine green near-infrared dye. We further validated the tumor specific accumulation of TEV-GIONs using MR imaging. Our findings demonstrate that the distribution pattern of the TEV-anti-miR-21-GIONs correlated well with the tumor-targeting capability as well as the activity and efficacy obtained in response to doxorubicin combination treatments. TEVs and TEV-GIONs are promising nanotheranostics for future applications in cancer molecular imaging and therapy.
View details for PubMedID 30346694
Synthesis and bio-evaluation of xylan-5-fluorouracil-1-acetic acid conjugates as prodrugs for colon cancer treatment
2017; 157: 1442–50
In the present study, xylan-5-fluorouracil-1-acetic acid (Xyl-5-FUAC) conjugates as colon specific prodrugs were synthesized and evaluated by in-vitro release study. The chemical stability of the conjugates was performed in acidic (pH 1.2) and basic buffers (pH 7.4), which showed their stability in upper gastrointestinal tract. The in-vitro drug release profiles of the conjugates were studied in the presence of rat's gastrointestinal contents. The results showed that the low amounts of drug 3-4% and 5-7% were released in gastric and small intestine contents respectively, while 53-61% of the drug was released in cecum and colonic contents. The cytotoxicity studies of the conjugates were also evaluated on human colorectal cancer cell line (HTC-15 and HT-29), which showed that the conjugates are more cytotoxic than the free drug. Therefore the results reveal that Xyl-5-FUAC conjugates are potential candidates for colon specific drug delivery in the treatment of colonic cancer with minimal undesirable side effects.
View details for DOI 10.1016/j.carbpol.2016.09.096
View details for Web of Science ID 000391896800161
View details for PubMedID 27987854
- Multifunctional carbon dots as efficient fluorescent nanotags for tracking cells through successive generations JOURNAL OF MATERIALS CHEMISTRY B 2016; 4 (28): 4862–71
Bioactive Core-Shell Nanofiber Hybrid Scaffold for Efficient Suicide Gene Transfection and Subsequent Time Resolved Delivery of Prodrug for Anticancer Therapy
ACS APPLIED MATERIALS & INTERFACES
2015; 7 (33): 18717–31
Nanofiber scaffold's ability to foster seemingly nonexistent interface with the cells enables them to effectively deliver various bioactive molecules to cells in the vicinity. Among such bioactive molecules, therapeutically active nucleic acid has been the most common candidate. In spite of such magnanimous efforts in this field, it remains a paradox that suicide gene delivery by nanofibers has never been sought for anticancer application. To investigate such a possibility, in the present work, a composite core-shell nanofiberous scaffold has been realized which could efficiently transfect suicide gene into cancer cells and simultaneously deliver prodrug, 5-Fluorocytosine (5-FC) in a controlled and sustained manner. The scaffold's ability to instigate apoptosis by suicide gene therapy in nonsmall lung cancer cells (A549) was ascertained at both phenotypic and genotypic levels. A cascade of events starting from suicide gene polyplex release from nanofibers, transfection, and expression of cytosine deaminase-uracil phosphoribosyltransferase (CD::UPRT) suicide gene by A549; subsequent prodrug release; and its metabolic conversion into toxic intermediates which finally culminates in host cells apoptosis has been monitored in a time-dependent manner. This work opens up new application avenues for nanofiber-based scaffolds which can effectively manage cancer prognosis.
View details for DOI 10.1021/acsami.5b05280
View details for Web of Science ID 000360322000063
View details for PubMedID 26234345
Controlled delivery of bPEI-niclosamide complexes by PEO nanofibers and evaluation of its anti-neoplastic potentials
COLLOIDS AND SURFACES B-BIOINTERFACES
2015; 131: 170–81
Since the turn of the 21st century, nanofiber based drug delivery systems have evolved drastically to attain controlled and sustained delivery of various bioactive molecules. In spite of such efforts, the tangible interface existing between the target cells and the drug molecules could not be narrowed down. This drawback has been overcome in this work by realizing nanofiber based scaffold for delivery of polymer-drug complexes rather than just the drug. In course with this, in the present study a differentially cross-linkable bPEI-PEO (branched-polyethylenimine-poly(ethylene oxide)) based nanofiber is fabricated for tunable delivery of bPEI-niclosamide complexes. Hydrophilic bPEI-niclosamide complexes are pre-synthesized and stabilized by crosslinking agent, which were then incorporated into bPEI-PEO nanofibers by electrospinning. The niclosamide loaded nanofibers by virtue of bPEI moieties presence were then cross-linked to different degrees which in turn altered bPEI-niclosamide release profile. The release kinetics of bPEI-niclosamide complexes from nanofibers was elucidated further by Korsmeyer-Peppas model. Apart from this, the versatile nature of bPEI-PEO nanofibers was also validated for different drug loading concentration and extent of crosslinking. The fibers antitumor efficacy was then assessed against A549 (Non-small cell lung cancer cells) and U-87 MG (glioblastoma cells) at two different time points (at 48h and 96h) in order to realize the importance of release profile in manifestation of different therapeutic outcomes. Thus, this work endows niclosamide a new life for anticancer application which has remained elusive till date due to its hydrophobic nature.
View details for DOI 10.1016/j.colsurfb.2015.04.063
View details for Web of Science ID 000357354800023
View details for PubMedID 25988281