The bacteria residing in your digestive tract, or your gut microbiota, may play an important role in your ability to respond to chemotherapy drugs in the clinic, according to a new study by scientists at the University of Massachusetts Medical School. Published in Cell, the study by Marian Walhout, PhD, and colleagues show that when a common research model, the roundworm Caenorhabditis elegan, is fed a diet of E. coli bacteria, the worms were one hundred times more sensitive to the chemotherapy drug floxuridine (FUDR) than worms who were fed different bacteria. FUDR is a commonly used drug to treat colorectal cancer.