ACGME Fellowship Program - Research Preceptors
Faculty members in the Section of Gastroenterology, Hepatology and Nutrition are currently involved in a number of basic and clinical research investigations on many different diseases and disorders. Below is a list of the research and clinical research faculty members and their interests.
ANDREW ARONSOHN, MD
Assistant Professor of Medicine
Chronic hepatitis C is a major risk factor for end stage liver disease and is a leading cause of liver related morbidity and mortality worldwide. As our population ages, we are encountering an increasing number of patients with hepatitis C who are 65 years old and older. Since older patients are usually excluded from clinical trials evaluating safety and efficacy of hepatitis C therapies, clinicians have limited evidence to base treatment decisions in this population. My primary research interest involves studying hepatitis C treatment outcomes in this understudied population. I have recently obtained funding to study the reasoning and clinical algorithms physicians employ when treating patients over 65. In addition I am investigating hepatitis C treatment outcomes in older patients as part of the PROPHYSES project which is a multicenter, multinational, observational study of over 8000 patients who have undergone hepatitis C therapy.
MARC BISSONNETTE, M.D.
Associate Professor of Medicine
My research interests include investigations to understand factors that cause cells lining the colon to become cancerous. Our laboratory is especially interested in how diet alters the susceptibility to develop colon cancer. We are studying Western diets that promote colon cancer growth and fish oil diets that inhibit tumor development. Dietary constituents have been shown to regulate growth factor signals. These growth factor signals are essential for healing colitis, but when chronically over active, growth factor signals can promote tumor development. Western diets turn on growth factor signals, whereas fish oil diets inhibit them. We believe these diet-induced differences in growth factor signals play central roles in the tumor-promoting versus tumor-inhibiting activities of diet. Recent studies have implicated colonic bile acids and bacteria in controlling these growth factors. Future research efforts will focus on understanding how bile acids and bacteria collaborate to activate growth factor signals that in turn promote colon cancer.
We are also studying the role of inflammation (e.g. ulcerative colitis) in colon cancer development. Ulcerative colitis, a chronic inflammatory disease of the colon, is an important risk factor for colon cancer. We are currently investigating two microRNAs important for cell differentiation that appear to be strongly down-regulated in ulcerative colitis. Since these miRNAs have been shown to be colonic tumor suppressors, we speculate that their down-regulations contribute to ulcerative colitis-associated colon cancer. In recent studies, we showed that dietary vitamin D increases these anti-tumor miRNAs in human colon. Thus vitamin D supplementation could offer a promising new dietary approach to prevent colon cancer in individuals with ulcerative colitis.
DAVID BOONE, PH.D.
Assistant Professor of Medicine
My research is focused on understanding the regulation of inflammation in the gut. I am particularly interested in the way bacteria and other germs activate the inflammation that damages the intestine in Crohn's disease and ulcerative colitis. In order to study the role of individual genes involved in inflammation, my laboratory makes "knockout mice" that each lack one specific gene of interest. This approach allows us to decipher what the role of a single gene is by examining what happens when that gene is absent. We also have begun to decipher the consequences of human gene alterations in IBD. While many genes that predispose to IBD have been discovered in the last year, the function of these genes remains unknown. To address this, we are creating new knockout and mutant human cells in a manner that parallels the technique of mouse knockouts. The advantage of this approach is to study human IBD gene functions in human cells, rather than in mouse models, and allowing us to rapidly translate results from the field of IBD genetics into new treatments or cures.
EUGENE B. CHANG, M.D.
Martin Boyer Professor of Medicine
Associate Director for Academic Programs and Training in Gastroenterology
Director: The Martin Boyer Laboratories
Our laboratory has been studying how chronic inflammation causes injury and dysfunction of the intestinal lining (epithelium) and how epithelial cells can be stimulated to protect the intestine from catastrophic injury. We have been studying the role of intestinal heat shock proteins, molecules present in all living cells, that can be rapidly induced improve intestinal survival even under adverse conditions. We have identified a number of molecular pathways for the regulation of heat shock protein gene expression which are unique to the intestinal mucosa. These pathways are stimulated by a number of IBD treatments, accounting in part for their therapeutic effects. More recently, the lab has been engaged in studies of host-microbial interaction. These investigations led to discovery of two important pathways of host defense. The first involves the identification of a newly discovered protein related to a gene that appears to contribute to increased risk of Crohn's disease. The second involves a unique family of proteins that can block the attachment and invasion of intestinal pathogens such as Salmonella – a major cause of food poisoning and diarrheal disease. Finally, we have developed a new core laboratory capable of studying the microbes lining the colon that are known to play a major role in the development of IBD. The analysis involves the application of computational science (bioinformatics) to define and identify bacterial species in the gut through their molecular signatures in health, inflammatory bowel disease and colon cancer.
RUSSELL D. COHEN, M.D., FACG, AGAF
Professor of Medicine
My research interests are primarily involved in two major areas of clinical gastroenterology: inflammatory bowel diseases and health care outcomes. We have been studying both standard and experimental pharmacological therapies, including novel immune modulating agents, as they affect outcomes such as "quality of life" and the economics involved in the diagnosis and treatment of Inflammatory Bowel Disease. By applying the principles of biostatistics, epidemiology, and other integral components of health outcomes research, I hope to address some of the perplexing issues arising in the field of gastroenterology in the face of a rapidly changing health care system.
IRA HANAN, M.D.
Associate Professor of Medicine
The rewards of practicing at a leading Academic Hospital and Top ranked program in Gastroenterology offer me the opportunity to practice at the highest level of knowledge and technology that provides my patients with the comprehensive approaches to simple and complicated GI disorders. My roles include Directing the Out-Patient GI Clinic and Clinical Teaching of our GI Fellows, Medical Residents and Students.
STEPHEN B. HANAUER, M.D.
(GIRF, in honor of Joseph B. Kirsner) Professor of Medicine and Clinical Pharmacology
Chief, Section of Gastroenterology and Nutrition
In addition to our large clinical practice, our group continues to perform extensive clinical research regarding the epidemiology, natural history and medical therapy for inflammatory bowel disease. Based upon the GIRF Women's Board sponsorship of the IBD registry (presently over six thousand patients with inflammatory bowel disease) we have explored the familial and genetic aspects of IBD, environmental contributors (e.g., smoking) and cancer surveillance. We have established guidelines for clinical trials in ulcerative colitis and Crohn's disease and have been at the forefront of developing clinical protocols and evaluating novel medical therapies for a spectrum of IBD scenario. These studies have led to the FDA approval of Rowasa enemas, Asacol, Pentasa, Dipentum, Entocort, Remicade and most recently Humira, Cimzia and Tysabri. We continue to study over ten new compounds and therapies for ulcerative colitis and Crohn's disease. Continued efforts are underway to optimize and select therapies for individual patients and disease groups. We are cooperating with the IBD research group to further classify and correlate genetic patterns with intestinal bacterial populations and clinical disease characteristics.
BANA JABRI, MD, PhD
Associate Professor of Medicine
The pathogenesis of Inflammatory Bowel Disease arises from a dysregulated immune response to the intestinal bacterial microflora. The loss of immune tolerance is thought to be a major cause of development of destructive inflammatory responses in the intestine. Our laboratory investigates how immune tolerance is achieved in the intestine and what factors can disrupt it. We have recently identified new pathways leading to immune regulation and dysregulation. We are currently testing agents that target these pathways and allow hence preventing or treating chronic intestinal inflammation. In particular we have identified IL-15 and retinoic acid (a vitamin A metabolite) as promoting inflammatory IFN-g responses to intestinal luminal antigens (Nature, 2011). This dysregulation may not only promote loss of tolerance to dietary antigens, but also explain loss of tolerance to the microbiota. Interesting in that regard, are reports indicating that Il-15 is overexpressed in the intestine of a subset of inflammatory bowel disease patients and that individuals who have received retinoic acid as a treatment for acne developed IBD. I have also developed a systems biology core to allow clinicians and basic scientists to conduct studies using information obtained in inflammatory bowel disease patients. We know now that human studies are required to determine new markers for diagnosis and prognosis, and develop new therapies. In the past two years we have established a data-base including presently 1000 inflammatory bowel disease patients. We know that inflammatory bowel disease is a very heterogeneous disease. Disease presentation, response to treatment and prognosis vary from patient to patient. It is therefore essential to describe and identify the different forms of disease. The goal of the systems biology core of the Digestive disease research Center is to provide the tools for translational and clinical research at the highest level. Finally, my laboratory continues to investigate the pathogenesis of celiac disease and is invested in developing a mouse model of celiac disease. Such a model is lacking and will be critical to develop new therapies and a vaccine that may prevent development of celiac disease in at risk children. Our goal is to provide alternative or complementary treatment to the gluten free diet and reduce the risk of celiac disease in children.
DONALD M. JENSEN, M.D.
Professor of Medicine
Director, Center for Liver Disease
Our main research focus is in the development and testing of newer and more effective therapies for the treatment of hepatitis C. During the past year, we have presented and published papers describing a new paradigm for the use of peginterferon and ribavirin in the treatment of the most difficult-to-treat population of hepatitis C patients (genotype 1), as well as a report on the outcomes following retreatment of prior nonresponder subjects. We are currently testing several new treatments for hepatitis C including: a novel therapeutic vaccine; several new HCV protease inhibitors (VX-950; BI1335; TMC435, ABT450/r), and two new HCV polymerase inhibitors (R7128, P7977). These exciting new treatments will revolutionize the treatment of this important disease.
KAREN E. KIM, M.D.
Associate Professor of Medicine
Director, Office of Community Engagement and Cancer Disparities, University of Chicago Comprehensive Cancer Center
Associate Investigator, University of Chicago Cancer Research Center
Faculty Affiliate, Center for the Study of Race, Culture and Politics
Faculty Affiliate, Center for Gender Studies
My interests are centered on women's health, health disparities and community based participatory research in two distinct areas. I have been an active public health advocate for reducing cancer disparities in Asian Americans. My research in hepatitis B in Asian Americans has focused on disaggregating Asian subgroups and studying the different and unique barriers to liver cancer prevention and treatment in these populations. I also study disparities in colorectal cancer prevention in minorities, with an emphasis on culturally competent educational interventions, which positively impact behavioral changes for colorectal cancer screening. Most recently, I am studying the feasibility of vitamin D in colon polyp prevention in African My other area of interest is in understanding educational methods for cultural competency training. As a member/trainer of the Center for Cross Cultural Education, I am involved in developing measures to understand the impact of cultural competency on patient care.
VANI J.A. KONDA, M.D.
Instructor of Medicine
My research interests are based on the early detection of malignant and premalignant lesions in the gastrointestinal tract and on novel endoscopic imaging techniques. As junior faculty member, I am fortunate to have Dr. Irving Waxman, Director of the Center for Endoscopic Research and Therapeutics, and Dr. Marc Bissonnette, Associate Professor of Medicine, as my co-mentors for my clinical and translational research. Confocal laser endomicroscopy, a novel imaging technology, is a part of my research program and allows for real time imaging of the gastrointestinal lining with microscopic detail in order to provide an "optical biopsy" during an endoscopic procedure. We use this technology in the esophagus, biliary tract, and colon in our endoscopy center to differentiate between normal and precancerous or cancer changes at a microscopic level. We are active in clinical studies to validate the early experience with this technology, in pilot studies to broaden this application of this technology in new ways, and in training courses to educate endoscopists interested in this technology. I investigate endomicroscopy as a means to identify premalignant changes at earlier stages, understand cancer formation in regards to pathways such as growth deregulation or blood vessel formation, and identify these changes in the setting of specific cancer therapies in animal models of colon cancer. I also have collaborations in studies that explore the use of nanotechnology in cancer detection with the Center for Nanoscale Materials at Argonne National Laboratories and the Backman Lab at the Biomedical Engineering Department at Northwestern University. My research interests also focus on the diagnosis and management of dysplasia in Barrett's Esophagus and are based on the large referral practice of patients with Barrett's esophagus and early neoplasia at our center.
My clinical interests include Barrett's Esophagus, reflux related diseases, esophageal diseases, and colon cancer screening and surveillance.
SONIA S. KUPFER, MD
Assistant Professor of Medicine
My clinical interests are primarily in caring for individuals with diseases with strong genetic risk factors including hereditary colorectal cancer and celiac disease. Currently, I see patients in the Cancer Risk clinic for evaluation of hereditary colorectal cancer syndromes (familial adenomatous polyposis and Lynch syndrome/HNPCC). In addition, I am a physician and board member of the Celiac Center at the University of Chicago.
The broad objective of my research program is the identification of genetic susceptibility factors that contribute to risk of colorectal cancer (CRC) development. I am particularly interested in identifying genetic factors in African Americans who have the highest CRC incidence and mortality of all US populations. These disparities have not been explained, and biological risk factors including genetic susceptibility to CRC are understudied in African Americans. To accomplish these studies, I have assembled a large series of African American CRC patients through collaborations with the University of North Carolina and the University of Illinois at Chicago. My long-term research goal is to bring this knowledge to the clinic to better risk stratify individuals for CRC screening and thereby prevent disease. As a junior faculty member, I am fortunate to have Dr. Nathan Ellis and Dr. Nancy Cox, Professor of Medicine and Chief of Human Genetics, as my co-mentors.
JOHN H. KWON, MD, PhD
Assistant Professor of Medicine
My research interest is in understanding how microRNAs, which are small, noncoding RNA molecules, are involved in the pathogenesis of inflammatory bowel disease (IBD). Our laboratory has identified microRNA molecules that are differentially expressed in ulcerative colitis and Crohn's disease tissues. These microRNAs can distinguish active disease from inactive disease and normal, healthy patients. We are in the process of examining whether blood-based microRNAs can distinguish different types of IBD or predict responsiveness to specific IBD therapies. We have also identified and demonstrated that microRNAs regulate the expression of genes involved in intestinal inflammation. Identifying these IBD-specific microRNAs and demonstrating their role in regulating IBD-related genes may lead to future microRNA-based diagnostic tests and therapies.
Recent research accomplishments include receiving a fundable score from NIH to study microRNA-mediated regulation of autophagy (to be funded in 2011). In addition, my laboratory has had 4 basic science or translational research publications related directly to our microRNA research accepted in major journals within the past 13 months.
YAN CHUN LI, PH.D.
Associate Professor of Medicine
Vitamin D-deficiency is associated with increased risk of inflammatory bowl disease (IBD) and colon cancer in humans. Our main research interest is to understand the mechanism by which vitamin D signaling regulates inflammation, epithelial barrier function and intestinal tumorigenesis. We recently found that patients with IBD have markedly reduced expression of vitamin D receptor (VDR) in the colon. In mouse models of IBD, we showed that mice that lack the VDR developed much more severe colitis, and in contrast, transgenic mice overexpressing the VDR in intestinal epithelial cells were protected from IDB. In fact, the VDR transgene was able to convey the protection in mice carrying global VDR deletion. These observations provide very compelling evidence that intestinal epithelial VDR plays a key role in protecting the colon from IBD. In colon cancer models, we found that VDR knockout mice developed more colonic tumor burden compared to normal mice, and we are investigating whether the VDR transgene protects the colon from tumor development. In addition, we plan to conduct a randomized placebo-control clinical trial to investigate the therapeutic effect of vitamin D supplementation in patients with IBD.
ANDREAS MYKONIATIS, MD
Clinical Associate
My research interest is primarily focused on intestinal secretion. Our lab has significantly advanced the knowledge of the pathophysiology of intestinal secretion diseases. More specifically, we were able to establish a direct link between leptin, a protein hormone that is implicated in appetite and metabolism, and the inflammation of the colon caused by C. difficile colitis. More recently we mapped the pathway of a major cotransporter involved in diarrheal diseases to a certain extent.
I am also involved in a project aiming to create new initiatives on Chicago's South side neighborhoods. Food deserts are areas that people cannot access nutritional food. Our aim is to study the reasons as well as to define ways to intervene in food deserts in the Chicago's Southside neighborhoods.
Most of my time is focused on patients with malabsorption and malnutrition. In order to nutritionally support them we use methods such as Total Parenteral Nutrition where protein, fats, and carbohydrates are infused into a vein.
JOEL PEKOW, MD
Instructor of Medicine
My primary research interest focuses on cancer development in IBD. Specifically, I am studying genetic expression patterns in premalignant and malignant lesions in patients with IBD. Because there are significant gaps in scientific knowledge as to why cancer develops in this high-risk population, prior efforts to prevent precancerous lesions have been generally unsuccessful. We propose to extend the knowledge we gain to develop new, less invasive indicators of precancerous lesions and ways to block molecular changes in order to ultimately prevent cancer in IBD. Because vitamin D deficiency is associated with several inflammatory conditions as well as non-IBD associated colon cancer, we are also interested in investigating the role of vitamin D in inflammation and IBD-associated cancer development. Along with several collaborators at the University of Chicago, we are currently embarking on a clinical study to investigate vitamin D in patients with ulcerative colitis.
NANCY REAU, MD
Associate Professor of Medicine
My current research efforts are centered on the prevention of fibrosis in various liver disorders as well as maximizing our understanding of current hepatitis C therapy. I also have both clinical and research interests focus on non-alcoholic fatty liver disease and developing therapies, improving Hepatitis B awareness and education, and Hepatitis C treatment.
GAUTHAM REDDY, M.D.
Assistant Professor of Medicine
Our liver group remains active in several clinical research studies exploring various therapeutic agents for viral hepatitis. More recently, our group has been more involved with clinical trials for novel therapies for complications of liver cirrhosis. This past year, I have been involved with a clinical trial using a novel drug to treat a neurological complication of advanced liver cirrhosis referred to as hepatic encephalopathy. We are also beginning a clinical trial using a novel medication to treat a type renal failure in advanced cirrhosis called hepatorenal syndrome. We have rapidly expanded our liver transplantation services and I am very active in the clinical efforts of our hepatology division. My clinical practice also includes general gastroenterology and IBD. I remain involved in the training of GI fellows, residents and medical students
B.H. GERALD ROGERS, M.D.
Clinical Associate of Medicine
I continue clinical research studies in 3 areas:
1) Endoscopic control of bleeding from the gastrointestinal tract without stopping anticoagulation.
2) Targeted endoscopic treatment of hemorrhoids.
3) Injection of Mitomycin C for inhibition of scarring in strictures of the gastrointestinal tract.
DAVID T. RUBIN, M.D.
Professor of Medicine
Associate Section Chief for Education
Co-Director, Inflammatory Bowel Disease Center
Associate Faculty, MacLean Center for Clinical Medical Ethics
Associate Investigator, University of Chicago Cancer Research Center
Medical Advisor, GIRF Associates’ Board
My research continues to focus on advanced technologies for screening and diagnosis in inflammatory bowel disease and prevention of colorectal cancer in these high risk patients. We are investigating whether inflammation at the microscopic level correlates to inflammation markers in the blood, inflammation activity seen during colonoscopy, and disease activity determined by patients' symptoms. Additionally, my group continues to study wireless capsule endoscopy ("the pill camera") for use in inflammatory bowel disease, and we are collaborating with the Department of Radiology for work in CT colonography (virtual colonoscopy), MRI and PET scans in IBD. We have also been the first in the world to utilize a novel device that measures pH and transit time in patients with IBD. The guiding principle of my work remains in accurate measurement of disease activity as a guide for disease-modifying therapy and better short- and long-term outcomes.
CAROL SEMRAD, M.D.
Associate Professor of Medicine
My interest is in small bowel disease and nutrition in particular celiac disease, diarrhea and malabsorption, the short bowel syndrome, and small bowel bleeding. I have written the chapter on diarrhea and malabsorption for the last three editions of the Cecil Textbook of Medicine and developed teaching slides on nutrition and the short bowel syndrome for the American Gastroenterological Association. I am a co-investigator on a research study on the pathogenic mechanisms of intestinal injury in celiac disease.
To improve diagnosis and treatment of small bowel diseases, I have developed an expertise in new endoscopic technologies including Video Capsule Endoscopy and Double Balloon Enteroscopy. Based on this work, the University of Chicago has one of the largest experiences in the country in the diagnosis and management of small intestinal bleeding and ulcerating diseases.
HELEN TE, M.D.
Assistant Professor of Medicine
My research interest lies mostly in hepatitis C and liver transplantation. I am interested in the prevention and treatment of recurrent hepatitis C following liver transplantation, and in the fine-tuning of immunosuppression in liver transplant recipients to decrease the side-effects while preserving graft function, with the intent of optimizing the long-term outcomes of liver transplant recipients.
In the past six months, I have been busier in my administrative role as the Medical Director of the Liver Transplant Program. Our Liver Transplant Program is at an exciting pivotal stage – we have a new surgical leadership in the person of Dr. John Renz, with whom I work very closely towards the goal of revitalizing our Liver Transplant Program. Since his arrival, we have increased the number of liver transplants performed in our center. The post-transplant management of these patients has also been shifted mostly to our hands, the transplant hepatologists, and we are maintaining optimal patient outcomes. We have streamlined our clinical operations by adopting a combined clinic model where we serve our transplant patients from a multidisciplinary approach in one clinic setting. We are also restructuring other areas of transplant operations with one major goal in mind – to serve our patients in the best way we can.
IRVING WAXMAN, MD
Professor of Medicine
Professor of Surgery
Professor of the Cancer Research Center
Director, Center for Endoscopic Research and Therapeutics (CERT)
My primary interests relate to the area of Gastrointestinal Oncology and early detection of gastrointestinal cancer with endoscopy. Our current programmatic efforts are focused towards new endoscopic imaging to detect early mucosal cancers utilizing confocal endomicroscopy as well as to use this technology guided by endoscopic ultrasound. Through our partnership with Dr. Backman, from the Department of Biomedical Engineering at Northwestern and Dr. Roy at ENH, we continue utilizing novel technology like four dimensional elasticity-scattered light fingerprinting (4D-ELF) and low coherence backscattering spectroscopy (LEBS) in order to study carcinogenesis in esophageal adenocarcinoma in Barrett's esophagus and now apply it for pancreatic cancer early detection.
Being one of the major centers in the Midwest interested in Barrett's esophagus and early esophageal cancer we have been able to create a large repository of clinical material for research. In collaboration with our own Thoracic Oncology group lead by Dr. Ravi Salgia, we have established a large tumor tissue resource that includes various human esophageal cancer tissue including Barrett's metaplasia and dysplasia (400-500 samples) which have corresponding clinical data that can be used to correlate experimental findings with clinical characteristics and available survival data. This has allowed his lab to identify that EphB4 (part of the family of tyrosine kinase receptors) is overexpressed and have increased gene copy numbers in esophageal tumors as well as being involved in enhanced motility and migration. This finding has potentially exciting applications for targeted biological therapies for esophageal cancer. Finally, in the clinical therapeutic arena, we continue to develop techniques and technology for endoluminal resection (minimally invasive surgery through the endoscope) and currently part of the national task force involved in introducing endoscopic submucosal dissection techniques in the US.
LESLIE WALLENE YANG, MD
Assistant Professor of Medicine
I am a general gastroenterologist with a clinical interest in colorectal cancer screening, gastroesophageal reflux disease and irritable bowel syndrome. My academic interest is in trainee education. I serve as the attending preceptor for the first year gastroenterology fellows‚ clinic and I am also the coordinator for various gastroenterology rotations for the medical students and internal medicine residents.