Immunotherapy has significantly changed how lung cancer and melanoma are treated. Unfortunately, only a small percentage of patients experience long-lasting responses. Gut bacteria have emerged as a potential predictor of how patients will respond to immunotherapy and may even be adjusted to enhance the effect of immunotherapy. Dr. Shaikh aims to identify features of the gut microbiome that correlate with immunotherapy responses. She will focus on both individual bacteria as they change over the course of treatment and the metabolites made by the entire bacterial community in the colon. The goal of this project, since gut bacteria can be modified, is to develop microbiome-based treatments to be used in combination with immunotherapy to improve response rates or overcome immunotherapy resistance for patients.