Abstract:
In this talk, I'll provide some most recent findings of my lab about developing algorithm, statistical approaches and deep neural networks for different biomedical problems as well as how we're translating them into clinics
Biography:
He received his B.Sc. and M.Sc. in computer engineering from Sharif University of Technology, and Ph.D. in bioinformatics from University of Tehran. He has been a bioinformatics researcher and head of bioinformatics lab at Royan Institute for Stem Cell Biology and Technology. He was a research associate at the Max Planck Institute of Molecular Biomedicine, and postdoctoral fellow of Bioinformatics in Colorado State University. He is currently Assistant Prof. of Bioinformatics in Computer Eng. Department, Sharif University of Technology. He is also a gold medalist of 12th International Olympiad in Informatics (IOI).
Speakers
Abstract:
Lung cancer is genomically diverse and remains the leading cause of cancer death worldwide with lung adenocarcinoma being the most common subtype. The development of targeted therapies for lung adenocarcinoma patients with oncogenic EGFR mutations or ALK, RET, or ROS1 translocations has greatly advanced clinical care and extended patient survival. However, about one third of lung adenocarcinomas lack known oncogenic drivers (representing over 200,000 patients per year worldwide) and thus lack these precision therapy options. In order to develop targeted therapy for these patients, it is necessary to identify key genomic alterations that contribute to oncogene-negative tumor initiation and growth.
Drivers in oncogene-negative lung tumors could be yet uncharacterized oncogenes, purely epigenetic modifications, or inactivation of single or combinations of tumor suppressors. Tumor suppressor mutations are enriched in oncogene-negative lung adenocarcinomas compared with tumors with known oncogenic drivers. However, the high rate of genomic alterations in lung adenocarcinomas complicates the identification of key driver genes in tumors without known oncogenic drivers. We hypothesized that combinations of tumor suppressor gene inactivation may enable the development of at least a subset of tumors without known oncogenic driver mutations. Here, we integrate Cre/Lox and somatic CRISPR/Cas9-genome editing to perform a broad analysis of the impact of pairwise alterations of tumor suppressor genes on lung tumor development in mouse models.
To quantify the effect of inactivating single and pairs of tumor suppressor genes on lung cancer initiation and growth in a high-throughput manner, we generated over 200 different genotypes in parallel in mice. We delivered barcoded lentiviral-Cre vectors expressing single guide RNAs targeting a pool of tumor suppressor genes to the lungs of mice with floxed alleles of Pten, Tp53, Lkb1, Keap1, and Nf1 as well as Cre-regulated fluorescent protein reporter and Cas9 alleles. One year after lentiviral transduction, we observed that inactivation of specific combinations of tumor suppressor genes can act as a tumor-driving event in lung cancer. Currently we are analyzing the nature of the engineered genetic alterations through high-throughput sequencing of barcoded regions, characterizing tumors at molecular and cellular levels, and validating these results. Our study sheds light on biology of oncogene-negative tumors and opens an avenue for the rational design of targeted treatment strategies for patients with these types of tumors.
Biography:
I have been working on stem cell biology and oncology for the past 9 years during my postdoctoral training with Dr. Monte Winslow at Stanford University, Ph.D. with Dr. Christopher Lengner at the University of Pennsylvania, and M.S.c. at the University of Tehran. My extensive experience includes the use of genetically engineered mouse models, Next-Generation Sequencing, pharmacogenomic analysis, and CRISPR/Cas9 genome editing to discover molecular pathways regulating stem cell self-renewal, tissue regeneration, tumor initiation, and drug response. I have been using this knowledge to regulate these pathways pharmacologically and using environmental cues such as nutrient modulation and calorie restriction to achieve desirable outcomes such as protection of epithelial tissues against injuries frequently caused by conventional cancer treatments such as radiotherapy. My long-term career goal is to use my rigorous training in molecular biology, regenerative medicine, and oncology to design efficient and safe drugs for cancer therapy.
The research and training available at the Stanford University and UPenn were ideal for me to grow as an independent and collaborative researcher. I gained proficiency in the use of the mathematical modeling and became capable of working productively with computational and mathematical collaborators. The strong connection between medical systems of these Institutes and research laboratories provided me with additional translational training through frequent interactions with clinicians to bridge the clinical-basic science gap. I have contributed to many projects, cultivated a mentoring style that motivate younger researcher, and gained skills of presenting data in a coherent and articulate manner to different audiences.
Abstract:
TBA
Biography:
I received my Master degree in Medical Biotechnology from University of Tehran (Iran) in 2005, investigating the efficiency of biodegradable nanoparticles for DNA vaccine administration in mouse models of allergy. I then started my PhD in Molecular Medicine (Pharmacology) at the Institute of Experimental and Clinical Pharmacology at Medical University of Graz (Austria), where I studied potential drug targets (G Protein-Coupled Receptors, GPCR) involved in inflammation.
After graduation in 2010, I started a 3-year postdoctoral work at Molecular Signal Transduction Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH/NIAID). At this position, I studied the impact of Regulators of G-protein Signaling (RGS) on the pathogenesis of asthma ex vivo and in vivo. This was followed by a 1-year postdoctoral work at University of Maryland School of Medicine exploring the mechanisms by which RGS proteins disturb the body calcium homeostasis. In 2015, I joined the Division of General & Oncologic Surgery at the Department of Surgery, University of Maryland School of Medicine as an assistant professor.
Abstract:
Adipose tissue plays a key role in systemic metabolism. There are two functionally distinct types of adipose tissue: white adipose tissue (WAT) is the major reservoir of energy, while brown adipose tissue (BAT) and its related beige fat are specialized for energy expenditure. Although numerous studies have demonstrated the presence of multiple cell types in adipose tissue, our understanding of heterogenous adipose tissue niche is limited. Additionally, different adipose depots undergo massive remodeling in response to environmental changes, such as cold and diet. Here, we harnessed the power of single cell RNA-sequencing (scRNA-seq) to uncover the cellular composition and temperature-dependent remodeling of BAT, WAT, and beige adipose tissue niche with single cell resolution. We identified distinct subpopulations of BAT and WAT precursor cells, immune cells, endothelial cells, and vascular smooth muscle cells in the SVF of each depot. Our analysis revealed novel markers that specifically mark brown and white adipocyte precursors and provided new insights into the coordinated changes in niche factors that accompany and support the functional adaptation to the ambient temperature. By comparing the transcriptional landscape of each component of the BAT and WAT niches from mice at different temperatures, we mapped distinct cellular states and transitional events leading to functional and structural remodeling of adipose tissue in the process of BAT activation, beiging of WAT, and whitening of BAT. In summary, scRNA-seq of BAT and WAT provides a high-resolution map of different cell types within their niche and suggests the critical contribution of these cell types to depot specific functions, tissue homeostasis, and turn over capacity.
Abstract:
Frame-disrupting mutations in the DMD gene, encoding dystrophin, compromise myofiber integrity and drive muscle deterioration in Duchenne muscular dystrophy (DMD). Removing one or more exons from the mutated transcript can produce an in-frame mRNA and a truncated, but still functional, protein. In this study, we developed and tested a direct gene-editing approach to induce exon deletion and recover dystrophin expression in the mdx mouse model of DMD. Delivery by adeno-associated virus (AAV) of clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 endonucleases coupled with paired guide RNAs flanking the mutated Dmd exon23 resulted in excision of intervening DNA and restored the Dmd reading frame in myofibers, cardiomyocytes, and muscle stem cells after local or systemic delivery. AAV-Dmd CRISPR treatment partially recovered muscle functional deficiencies and generated a pool of endogenously corrected myogenic precursors in mdx mouse muscle.
Biography:
Sharif Tabebordbar is a postdoctoral fellow in the Sabeti lab. Sharif’s research is focused on engineering adeno-associated viruses (AAVs) to develop tissue-specific gene delivery vehicles and to improve safety of AAV-mediated gene delivery for gene editing applications.
Sharif received his BSc and MSc degrees in biotechnology from University of Tehran and his Ph.D. in Developmental and Regenerative Biology from Harvard University. During his Ph.D., he developed culture conditions to expand healthy and diseased adult muscle stem cells in culture and provided the proof of concept for correcting the genetic mutation in these cells using gene editing technology. He also provided evidence for the feasibility of an in vivo gene editing-based approach to treat Duchenne Muscular Dystrophy (DMD) and investigated the host immune response after delivery of gene editing components into animals. The results of his research have been published in several peer-reviewed journals including Cell, Science and Nature Methods. Sharif is also the recipient of Distinction in Teaching Award from Derek Bok Center for Teaching and Learning at Harvard, Albert J. Ryan Foundation Award for Outstanding Graduate Students in Biomedical Sciences, Excellence in Research Award from American Society of Gene and Cell Therapy and Royan International Research Award in Regenerative Medicine. Sharif’s research in the Sabeti lab is partly supported by the Merkin Institute for Transformative Technologies in Healthcare.