Hemant K Roy, M.D., Professor of Medicine, Chief, Section of Gastroenterology
Dr. Roy joined the faculty in 2013. He completed his medical degree from Northwestern University with distinction and completed internal medicine residency at Beth Isreal followed by GI Fellowship at University of Chicago.
Dr. Roy’s research interests center on GI cancer risk stratification using intermediate biomarkers of field carcinogenesis. He has been involved in the development and clinical implementation of a variety of biophotonic techniques for risk stratification encompassing both fiberoptic probes and cytological based techniques and these are complemented by a variety of molecular markers including microRNAs.
This has served as a platform for assessing risk modification via chemoprevention and applied to a number of non-GI malignancies including lung and ovarian cancer. Dr. Roy is a fellow of the American Gastroenterological Association and member of the Early Detection Research Network and the Cancer Biomarkers Study Section of the NIH.
More clinically, his interests are in high risk colon cancer syndromes and role of gender in colorectal cancer screening. Throughout his career he has also been involved in teaching receiving numerous awards in this regard.
Uri Avissar, M.D., Assistant Professor of Medicine
Dr. Avissar joined the faculty of the Section of Gastroenterology in 2008. Dr Avissar received his medical degree at the University of Rochester School of Medicine and Dentistry. After finishing his internal medicine residency at the University of Pittsburgh Medical Center, he went on to complete a fellowship in gastroenterology and a fellowship in transplant hepatology at the University of Cincinnati. While maintaining a broad interest in gastroenterology, Dr. Avissar’s clinical focus is in hepatology, and his practice encompasses all aspects of liver disease. His particular interests include the evaluation of liver transplant candidates and the medical management of liver transplant recipients. Dr. Avissar is also avidly involved in medical education and currently serves as the Assistant Fellowship Director for the Section.
Charles M. Bliss, Jr., M.D., FACP,AGAF, Assistant Professor of Medicine
Dr. Bliss practice mainly consists of general gastroenterology. His interests in clinical practice include H. pylori treatment and inflammation. As part of his practice, Dr. Bliss has included some of his patients in clinical studies, including the studies of Dr. Nunes with regard to dosing of interferon in hepatitis C, and the studies regarding markers of fibrosis in liver disease. He has been also a collaborator in Dr. Schroy’s study regarding colon cancer screening by flexible sigmoidoscopy.
Audrey H. Calderwood, M.D., M.S., Assistant Professor of Medicine
Dr. Calderwood received her medical degree from the University of Chicago’s Pritzker School of Medicine. She completed her internal medicine residency at the University of Chicago and the Brigham and Women’s Hospital, followed by gastroenterology fellowship at Boston Medical Center. Dr. Calderwood’s clinical interests include general gastroenterology, high-risk cancer syndromes, and celiac disease. Her research focuses on quality in gastroenterology, specifically colorectal cancer screening and surveillance. She is the recipient of an NIH Career Development Award (K08). She is a Fellow of the American College of Gastroenterology and serves on its Practice Parameters Committee. She is an active member of the American Society of Gastrointestinal Endoscopy where she serves on the Quality Assurance in Endoscopy Committee. She received her Master’s Degree in Health Services Research from the Boston University School of Public Health.
Lizabeth Cline, NP Instructor of Medicine
Ms. Cline received her BS in Nursing in 1982 from Boston University and her MSN from Syracuse University in 1995. Ms. Cline’s clinical focus is liver disease including fatty liver disease and viral hepatitis.
Francis A. Farraye, M.D., MSc, Clinical Director, Section of Gastroenterology and Co-Director, Center for Digestive Disorders, Professor of Medicine, Boston University School of Medicine
Dr. Farraye received his medical doctorate from Albert Einstein College of Medicine in New York. He completed an internal medicine residency and gastroenterology fellowship at the Beth Israel Hospital in Boston. Dr. Farraye received a Masters Degree in Epidemiology from the Harvard School of Public Health.
Dr. Farraye’s clinical interests are in the care of patients with inflammatory bowel disease and the management of colon polyps and colorectal cancer. He is currently investigating C. difficile infection in IBD patients, the management and diagnosis of dysplasia and cancer in patients with IBD; pouchitis after ileal pouch anal anastomosis; vaccinations in patients with IBD; and the role of serrated polyps as an alternative pathway to the development of colorectal cancer.
A frequent speaker and invited lecturer on topics on the diagnosis and management of inflammatory bowel disease, Dr. Farraye has authored or co-authored over 300 original scientific manuscripts, chapters, reviews, and abstracts. He is an associate editor for Therapy for Digestive Disorders. He is the series editor for the text Curbside Consultations in Gastroenterology and co-wrote the text, Curbside Consultation in Inflammatory Bowel Disease and Gastrointestinal Emergencies. His newest books for patients are Questions and Answers about Ulcerative Colitis, Questions and Answers about Crohn’s Disease and Ulcerative Colitis for Dummies.
Dr. Farraye is a Fellow of the American College of Physicians, American Society of Gastrointestinal Endoscopy, American Gastroenterological Association and the American College of Gastroenterology. He has served on numerous committees and currently is a member of the ACG Board of Trustees and the Chapter Medical Advisory Committee for the New England CCFA where he was past chairman. The New England CCFA named Dr. Farraye Humanitarian of the Year in 2003. In 2009, the ACG awarded Dr. Farraye the William Carey Award for service to the college. Dr. Farraye was recognized as “Top Doctor” in Gastroenterology by Boston Magazine and U.S. News and World Report 2010 through 2013. In 2013, he received the Clinical Research Mentor of the year award from the house staff in the Department of Medicine at Boston Medical Center.
Albena Halpert, M.D., Assistant Professor of Medicine
Dr. Halpert joined the faculty of the Section of Gastroenterology in 2004. After earning her medical degree at the Charles University, Prague, Czech Republic, Dr. Halpert trained in internal medicine in England and than she completed her residency in Internal Medicine, followed by a fellowship in Gastroenterology at St. Louis University. Dr. Halpert also completed an additional two years of training in Functional Bowel Disorders and clinical research at the Center for Functional GI Disorders at the University of North Carolina, Chapel Hill. Her clinical research activities revolve around all aspects of IBS, particularly the impact of patient education on IBS clinical outcomes and the patient-physician relationship. Other areas of interest include antidepressant treatment in IBS, anorectal motility, and gender related issues.
Christopher Huang, M.D., Assistant Professor of Medicine
Dr. Huang joined the faculty of the Section of Gastroenterology in 2004 and is an Assistant Professor of Medicine at Boston University School of Medicine. He received his undergraduate degree from Cornell University in 1994, and his medical degree from New Jersey Medical School in 1998. He completed his residency in Internal Medicine at Brigham and Women’s Hospital, followed by a fellowship in Gastroenterology here at Boston Medical Center.
Dr. Huang is a clinician-educator with particular interest in therapeutic endoscopy and endoscopy training. He performs a wide range of diagnostic and therapeutic endoscopy procedures, including endoscopic retrograde cholangiopancreatography, endoscopic ultrasonography, endoscopic mucosal resection, enteral stenting, and radiofrequency ablation of dysplastic Barrett’s esophagus. His other clinical interests include colorectal cancer prevention and management of gastrointestinal complications of bariatric surgery. He is actively involved in the education and training of Gastroenterology fellows and Internal Medicine residents at Boston Medical Center, and currently serves as the Subspecialty Education Coordinator for the Internal Medicine residency training program. His regular teaching responsibilities include lecturing on various topics to medical residents and Gastroenterology fellows, and teaching in several courses at Boston University School of Medicine and School of Dental Medicine. His academic interests revolve around the role of serrated polyps in colorectal cancer pathogenesis, and he has co-authored several articles on the topic in peer-reviewed journals. He has also authored Up-To-Date topic cards on Endoscopy in Bariatric Surgical Patients and ERCP in patients with Roux-en-Y anatomy.
Dr. Huang as participated on the faculty of the Boston International Live Endoscopy Course and Harvard’s Advanced Diagnostic and Therapeutic Endoscopy Course. Dr. Huang is a member of the American Society for Gastrointestinal Endoscopy, the American Gastroenterological Association, the American College of Gastroenterology, and the Massachusetts Gastroenterology Association.
Brian C. Jacobson, M.D., M.P.H., Director of Gastroenterology Quality Improvement, Associate Director of Endoscopy Services, Associate Professor of Medicine
Dr. Jacobson serves as the Director of Endoscopic Ultrasonography and Associate Director of Endoscopy Services at Boston Medical Center. He is also an Associate Professor of Medicine at Boston University School of Medicine. Dr. Jacobson received his undergraduate degree from Amherst College, his medical degree from Albert Einstein College of Medicine, and his Masters Degree in Public Health from Harvard University School of Public Health. He completed both his residency in Internal Medicine and his fellowship in Gastroenterology at Brigham and Women’s Hospital. He later served as Chief Medical Resident at Brigham and Women’s followed by a fellowship in Advanced Interventional Endoscopy at the Brigham and Women’s and Massachusetts General Hospitals.
Dr. Jacobson performs endoscopic ultrasonography with fine-needle aspiration, ERCP, endoscopic mucosal resection, and places internal stents for palliation of malignant obstructions. He participates in the training of fellows, residents, and medical students at Boston Medical Center and Boston University School of Medicine. Dr. Jacobson’s research interests focus on the epidemiology of gastroesophageal reflux and Barrett’s esophagus as well as esophageal cancer. He serves as a Councilor on the Governing Board of the American Society for Gastrointestinal Endoscopy, and is an Associate Editor for the journal Gastrointestinal Endoscopy
Robert Levine, M.D., Professor of Medicine
Dr. Robert Levine is a graduate of Cornell University and Cornell University Medical College. He did his Residency in Internal Medicine at Cornell University Medical College, and Fellowships in Gastroenterology and Hepatology at Cornell University Medical College and Yale University School of Medicine respectively. He subsequently was Chief of the Metabolic Division of the U.S. Army Research and Nutrition Laboratory at Fitzsimmons General Hospital; Chief of Gastroenterology at State University of New York, (SUNY), Downstate Medical Health Center, Brooklyn, NY; and SUNY Upstate Medical University, Syracuse, New York, where he served as Professor of Medicine and Chief of Gastroenterology for over twenty-two years. His clinical and research endeavors have focused on mechanisms of gastric secretion, role of non-steroidal anti-inflammatory drugs on gastric secretory function, experimental models of ileitis and colitis, and studies in chronic hepatitis and other liver diseases. Dr. Levine was a recent co-principal investigator of an NIH (NIDA) funded grant entitled: “Improving Hepatitis C Treatment Outcomes in Injection Drug Users”, and a site investigator of the New York-New England Consortium of the Drug-Induced Liver Injury Network, funded by the NIH. He received the SUNY President’s Award for Research in 1987, and for teaching medical students in 1995. He was honored also by the American Gastroenterological Association receiving their 2007 Mentor’s Research Scholar Award for exemplary contribution to Gastroenterology through mentoring and research. He has trained over 65 Gastroenterology trainees under his guidance to insure that young gastroenterologists and scientists throughout the nation and around the globe are ready to research, diagnose, and treat gastroenterological diseases. He has performed governmental service as a member of the National Institutes of Health Digestive Diseases Advisory Board from 1992-1998. He has also been a member of the Food and Drug Administration Gastroenterology Advisory Committee from, 2001-2005, and is currently a consultant for the Food and Drug Administration – Center for Drug Evaluation and Research. Dr. Levine was cited in the Best Doctors in America, Northeast Region. He has published over 120 peer-reviewed papers, including in the following journals: Nature (wherein he was the first to infuse Cyclic AMP and later prostaglandins in humans and canines), Proceedings of the Society of Experimental Biology and Medicine, Biochemistry, Biophysics ACTA and multiple publications in the Journal of Clinical Investigation, Journal of Biological Chemistry, American Journal of Physiology, Journal of Pharmacology and Experimental Therapeutics, New England Journal of Medicine, Annals of Internal Medicine, Gastroenterology, Hepatology, and Gut. He has written 16 book chapters, and served as a reviewer for 30 journals. He has been on the editorial boards of Hepatology, Annals of Internal Medicine, the International Journal of Molecular Medicine, and since 2008, Digestive Diseases and Sciences. He is a Fellow of the American College of Physicians, the American College of Gastroenterology and the American Gastroenterological Association. He led the Gastroenterology Research Laboratory at SUNY Upstate Medical University in Syracuse, NY. He joined the faculty of the section of Gastroenterology, Boston University School of Medicine in 2010.
David R. Lichtenstein, M.D., FACG Director of Gastrointestinal Endoscopy Associate Professor of Medicine
Dr. Lichtenstein is the Director of the Gastrointestinal Endoscopy at
Dr. Lichtenstein is currently the director of endoscopy at Boston Medical Center where he directs a state-of-the-art center with dedicated facilities for performing a wide array of endoscopic procedures inclusive of advanced technologies such as ERCP, endoscopic ultrasonography, radiofrequency mucosal ablation, and deep enteroscopy. He supervises Gastroenterology Fellowship training in advanced endoscopic procedures and is responsible for evaluating and implementing new endoscopic technologies at Boston Medical Center. His main interests focus on the development and application of endoscopic approaches for diagnosing and managing gastrointestinal hemorrhage, pancreaticobiliary tract disorders, and gastrointestinal malignancies.
Dr. Lichtenstein is an active member and current Fellow of the American Society for Gastrointestinal Endoscopy (ASGE),
Robert C. Lowe, M.D., Associate Professor of Medicine and Educational Director of the Section of Gastroenterology at Boston Medical Center
In his role as Education Director for the Section, he coordinates educational activities for the Fellowship program and directs the Pathophysiology course at the Boston University School of Medicine. In addition, he has an active role in the Medical Residency Program, serving as an Evans Educator. In this role, he attends frequently on the inpatient Medicine Service and facilitates educational conferences twice a month for the Medicine Housestaff and students.
His clinical focus is in hepatology, and his practice encompasses all aspects of liver disease. His particular interests include the treatment for viral hepatitis, the management of cirrhosis and the complications of advanced liver disease, and the management of metabolic liver diseases.
Hannah Miller, M.D., Assistant Professor of Medicine
Dr. Miller is currently an Associate Professor of Medicine at Boston University School of Medicine. Dr. Miller is a graduate of
Dr. Miller’s clinical interests include constipation and pelvic floor disorders, gastroesophageal reflux disease and inflammatory bowel disease. Her research interests include clinical issues in inflammatory bowel disease and polyp detection in colorectal cancer screening.
Dr. Miller served on the Graduate Training Examination subcommittee of the American Gastroenterology Association for three years. She currently serves on the Women in Gastroenterology committee of the American College of Gastroenterology. She is a member of the American Gastroenterology Association and American College of Gastroenterology, and The Crohn’s Colitis Foundation of America.
T. Carlton Moore, M.D., Assistant Professor in Medicine
Dr. T. Carlton Moore joined the Section of Gastroenterology after completing gastroenterology fellowship here at Boston Medical Center. He received his medical doctorate from Johns Hopkins School of Medicine and completed internal medicine residency at the Hospital of the University of Pennsylvania.
Dr. Moore’s principal area of research involves the characterization of the trophic effects of gastrin peptides on esophageal adenocarcinoma. This neoplasm arises in individuals with Barrett’s metaplasia due to chronic gastroesophageal reflux disease (GERD) and is associated with a poor prognosis. Although highly effective acid-reducing agents (proton pump inhibitors (PPIs) have provided symptomatic relief and healing in patients with mucosal injury secondary to the erosive effects of gastric acid and other gastric contents, the incidence of esophageal adenocarcinoma continues to climb dramatically. The low acid state caused by PPIs can disrupt an important negative feedback mechanism, whereby gastrin expression is normally inhibited by the postprandial stimulation of acid secretion, resulting in hypergastrinemia. The trophic effects of gastrin on gastrointestinal epithelial cells of gastric, colorectal, and pancreatic origin are well described. However, gastrin-induced growth has not been previously described in esophageal cancer.
Laboratory investigations include (1) elucidating the signaling pathways underlying gastrin-enhanced growth in esophageal adenocarcinoma, (2) characterizing a functional gastrin receptor on human esophageal adenocarcinoma cells, and (3) developing a nude mouse model to examine the in vivo effects of hypergastrinemia on esophageal adenocarcinoma growth. These studies address the hypothesis that inhibition of antral gastrin expression might be beneficial in decreasing the progression of this frequently fatal malignancy.
Gustavo Mostoslavsky, M.D., Ph.D., Assistant Professor of Medicine
Dr. Mostoslavsky received his M.D. from the University of Tucuman in Argentina and his Ph.D. from the Hebrew University in Jerusalem, Israel. His longstanding interest in basic science and regenerative medicine brought him to the laboratory of Dr. Richard Mulligan at Harvard Medical School to pursue postdoctoral studies with stem cells and gene therapy. In 2008 Dr. Mostoslavsky was recruited to the faculty of the Section of Gastroenterology in the Department of Medicine at Boston University School of Medicine.
Dr. Mostoslavsky Lab is a basic science laboratory and his goal is to advance our understanding of stem cell biology with a focus on their genetic manipulation via gene transfer and their potential use for stem cell-based therapy. In 2010 Dr. Mostoslavsky founded and Co-directs the Center for Regenerative Medicine (CReM) at BUSM, which has recently moved into a new state-of-the-art facility, comprising six Research Programs. Project areas in the lab focuses on the use of different stem cell populations, including embryonic and induced Pluripotent stem cells, hematopoietic stem cells and intestinal stem cells. For more details visit www.mostoslavskylab.com
Ansu Mammen Noronha, M.D., Assistant Professor of Medicine
Dr. Noronha joined the Section of Gastroenterology in 2009 after completing a gastroenterology fellowship at Boston University School of Medicine. She received her medical doctorate from
David P. Nunes, M.D., Associate Professor of Medicine, Director of Hepatology
Dr. Nunes has achieved considerable expertise and prominence in the area of hepatitis C/HIV co-infection and noninvasive evaluation of hepatic fibrosis markers, and he is now considered one of the foremost experts in this area throughout the United States. Despite a number of competing clinical, teaching and administrative duties, Dr. Nunes has been able to maintain a deep commitment to research. During his tenure at Boston Medical Center, his research activities have evolved from mostly basic science work related to elucidating the molecular basis of gallstone formation to more translational and clinical work related to the evaluation of non-invasive markers of liver fibrosis and the treatment of hepatitis C/HIV co-infection. He has authored or co-authored 47 original articles in peer reviewed journals, four book chapters, two electronic publications and 48 abstracts. His work has been presented at numerous national and international meetings of a wide variety of professional organizations. He has also been invited to serve on several ad hoc NIH grant review committee, attesting to his prominence as an investigator in the area of hepatitis C control.
Gwynneth Offner, Ph.D., Associate Professor of Medicine and Biochemistry
Dr. Offner’s laboratory has had a long-standing interest in the structure, function and regulation of epithelial mucins. During the past decade, cloning studies on epithelial mucins have identified at least twenty distinct mucin genes, which can be divided into two groups: membrane-associated and secreted gel-forming mucins. Recent studies in her laboratory have focused on the former, specifically on MUC1. MUC1 is overexpressed in many cancers, including breast, colon, pancreatic and lung. Using RNA interference, her laboratory has shown that suppression of MUC1 gene expression leads to changes in cell phenotype and a decrease in the metastatic potential of cells.
MUC1 is also expressed in normal cells, where it functions in epithelial cell protection. Dr. Offner’s hypothesis is that membrane bound mucins interact with secreted mucins to enhance the epithelial protective barrier. She has identified specific domains in the secreted mucin MUC5B which interact with a domain at the amino-terminal end of MUC1. Currently, she and her colleagues are investigating the binding of other proteins to the mucin scaffold, which could modulate mucin function in different cell and tissue types. The integrity of the mucin scaffold may have particular relevance to the pathogenesis of inflammatory bowel disease and this is a current focus in the laboratory.
Angela Reffel PA-C, MHP, Physician Assistant, Instructor of Medicine
Angela Reffel received her Bachelor’s Degree at
Elihu M. Schimmel, M.D., Professor of Medicine
Dr. Schimmel has focused a career of clinical investigations on several gastrointestinal disorders particularly prevalent in the population of military veterans: Barrett’s esophagus, inflammatory bowel disorders (Crohn’s Disease, ulcerative colitis and infectious colitis), and chronic pancreatitis. In addition, he has maintained a longitudinal study of patients whose gastrointestinal diseases have been treated surgically: clinical follow-up of patients undergoing esophageal resection for cancer; patients who have had gastric surgery for peptic ulcer disease; post-colectomy ileostomy; and those who have had pancreatic surgery for pancreatic inflammatory disease. Since 1976, he has served on the Nutrition Support Program at the VA Boston Healthcare System with special interest in protein metabolism and the nutritional requirements for amino acids. Since 1992, he has been in the forefront of implementation of the Computerized Patient Record System at the Boston VA, and in the use of computer-based technology for the management of clinical data. Lastly, he has an active interest in the cognitive processes of collecting and analyzing clinical data in patients with disorders of the gastrointestinal system in arriving at assessments for the formulation of diagnostic and therapeutic plans. Dr. Schimmel has developed expertise in the area of translational teaching, bringing the results of laboratory research to the care of patients for fellows, residents, and medical students in the outpatient clinics and at the hospital bedside in a didactic synthesis.
Paul C. Schroy, III, M.D., M.P.H., Professor of Medicine and Director of Clinical Research for the Section of Gastroenterology
Dr. Paul Schroy is a graduate of
Utilizing an integrated approach that incorporates a strong background in laboratory research, clinical experience and public health training, Dr. Schroy’s research activities focus primarily on the development, implementation and evaluation of model programs for community-based colorectal cancer control. Current ongoing studies are exploring: (1) the role of shared decision-making as a strategy for increasing patient participation in colorectal cancer screening; (2) the development of a risk assessment tool for predicting the presence of advanced neoplasia at screening colonoscopy; (3) the feasibility and validity of novel colorectal cancer screening strategies such as stool-based DNA testing and virtual colonoscopy; and (4) quality issues related to colorectal cancer screening.
Satish K. Singh, MD, AGAF, Associate Professor of Medicine, Biomedical Engineering, and Molecular & Translational Medicine
The Singh Lab is focused on translational research spanning concept to clinical application. Our main interests are (1) novel biophotonic approaches to endoscopic diagnosis and treatment (2) point-of-service diagnostics using optical and nano-scale technologies, and (3) hormonal regulation of gut epithelial nutrient transport related to obesity and diabetes.
Our laboratory uses technological advances to address specific clinical needs by bridging disciplines rigorously. Together with colleagues in the BU College of Engineering, we have developed novel spectroscopically-guided tools that aid in “optical biopsy,” or tissue classification in situ and in real-time. These low-cost, clinically-friendly “smart” instruments are accessible to any practitioner and can be used to guide biopsies, detect tumor margins, identify dysplastic tissue, and assess for the presence of cancer and disease field effects in real-time during endoscopy. In another project, we have developed a novel fiberoptically-mediated confocal fluorescence endomicroscope that can be used to reveal unprecedented structural and functional detail in situ during endoscopy. In the area of nanotechnology, we have developed a handheld disposable nanoscale microfluidic system capable of isolating nucleic acids from bacteria in clinical samples. As a result, we can perform on-chip- PCR detection of stool pathogens including Clostridium difficile.
At VA Boston, I am overseeing a new, six-room state-of-the art endoscopy facility that will open in Q1 2014. This “endoscopy unit of the future” will provide a breadth of cutting-edge capabilities unparalleled in the nation for patient care, research, and training. Capabilties will include confocal & optical coherence endomicroscopies; contrast-enhanced endoscopic sonography; elastography; electromagnetic navigation endoscopy; full HD video integration, digital pathology scanners; virtual reality simulation & training; enhanced capsule endoscopy, and the newest HD wide-angle multiband endoscopes for all applications.
At the “bench,” in the field of integrative physiology, we have recently published that the physiological incretin hormone, GIP, in fact directly stimulates intestinal nutrient uptake. This novel hormonal “entero-enteric axis” may be key to the pathogenesis of obesity, type-2 diabetes, glycemic control and the anabolic response to feeding. We continue work on elucidating the mechanisms of incretin-regulated nutrient absorption using a variety of state-of-the art cellular and molecular biological approaches.
Kathleen Sullivan, MSRN, ANP
Kathleen Sullivan is a nurse practitioner for the Section of Gastroenterology at Boston Medical Center. She received her Master of Arts in Clinical Psychology and later received her Master of Science in Nursing and Adult Primary Care at MGH Institute of Health Professions. She is certified as an Adult Nurse Practitioner, and is a member of the National Honor Society for Nursing. Through her gastroenterology experience, she has developed a special interest in inflammatory bowel disease.
Ramesh Wali, Ph.D., Associate Professor of Medicine
Dr. Wali joined the faculty in 2013. Dr. Wali received his doctorate degree from the Postgraduate Institute of Medical education and Research; Chandigarh, India. He did his postdoctoral fellowship from the University of South California before taking faculty positions at the University of Chicago, Chicago, IL and later at Northwestern University, Evanston, IL. Dr. Wali has long standing research interest is in the area of cancer biology especially in identifying and characterizing new biomarkers for early detection and chemoprevention of colon cancer. He has been involved in number of bench-to-bedside projects translating basic scientific findings into therapeutic intervention and risk-stratification. Dr. Wali is a member of the American Association of Gastroenterology.
Sharmeel K. Wasan, M.D., Assistant Professor of Medicine
Dr. Wasan received her medical doctorate from Albert Einstein College of Medicine in
H. Christian Weber, M.D., Assistant Professor of Medicine
The major interest of Dr. Weber’s laboratory focuses on the investigation of molecular mechanisms of mammalian bombesin receptor expression and their intracellular signal transduction pathways in human cancers and obesity. This family of G protein-coupled receptors comprise the gastrin-releasing peptide receptor (GRP-R), the neuromedin B receptor (NMB-R), and the orphan bombesin receptor subtype-3 (BRS-3). With the exception of BRS-3, they are predominantly expressed in the CNS and the gastrointestinal (GI) tract where they mediate important physiologic functions, such as gastric acid secretion, pancreatic secretion, and smooth muscle contraction. Moreover, after ligand-specific activation of the GRP-R in prostate, gastric, colon, and pancreatic cancer cells mediates potent mitogenic properties. In addition, it has now been clearly established in the murine model that GRP-R and BRS-3 play a significant role in energy metabolisms, satiety and obesity.
Accordingly, Dr. Weber’s laboratory is investigating the human GRP-R and BRS-3 gene regulation and their intracellular signaling pathways to determine molecular mechanisms important in gastrointestinal cancer cell proliferation and in obesity. Studies also include the immunohistochemical localization of the receptor molecules in various tissues, structure and function analysis of the human bombesin receptor proteins, and genetic epidemiological studies of bombesin receptor protein mutations. Other interests of Dr. Weber include the genotype-phenotype analysis of patients with familial polyposis syndromes, such as Cowden disease, the pathophysiology of gastric acid secretion, and the molecular pathomechanisms involved in the development of neuroendocrine tumors, such as gastrinoma (Zollinger-Ellison syndrome).