Investigator, Instructor (M) Mongan Institute, Mass General Research Institute

Assistant Investigator Clinical and Translational Epidemiology Unit, Massachusetts General Hospital

adiposity; bile acids and salts; colorectal cancer; exercise; gut microbiome; metabolomics; metagenomics; motility; prostate cancer

Dr. Kai Wang is currently an Assistant Investigator and Instructor of Medicine at the Massachusetts General Hospital (MGH) and Harvard T.H. Chan School of Public Health (HSPH), with joint appointments in Epidemiology, Nutrition, and Gastroenterology. He earned his PhD in Epidemiology from the University of Florida and completed postdoctoral training at HSPH and MGH. Dr. Wang’s research focuses on the gut microbiome-bile acid axis and its critical role in colorectal cancer prevention and gastrointestinal health. His laboratory investigates how dietary exposures shape microbial communities and orchestrate bile acid metabolism, with particular attention to inter-microbial interactions, including bacteria-archaea cooperation, that drive complex bile acid biotransformations. These transformations modulate colonic motility, local inflammation, metabolic signaling, and the initiation and progression of colorectal neoplasia. Dr. Wang’s work explores novel bile acid metabolites, particularly secondary bile acid structural derivatives and amino acid conjugates, and their engagement with emerging bile acid receptors in the colon, providing mechanistic insight into host-microbe communication. His research integrates epidemiology, microbiology, metagenomics, metatranscriptomics, metabolomics, and physiology to uncover new microbial functions in bile acid metabolism and identify actionable pathways for personalized dietary interventions. He is the PI of an NCI K99/R00 grant investigating diet-gut microbiome-bile acid pathways for colorectal cancer prevention, using both populational and mechanistic studies. He leads an ongoing clinical trial (NCT07162337) evaluating dietary interventions on bile acids, the gut microbiome, and colorectal cancer risk biomarkers, with a focus on novel bile acid metabolites and receptor-mediated pathways as potential targets for precision prevention strategies. By bridging epidemiology, clinical research, and mechanistic science, Dr. Wang aims to develop tailored interventions that modulate microbial metabolism and bile acid signaling to reduce colorectal cancer risk and improve gastrointestinal health.