Certain gut bacteria may explain the link between inflammatory bowel disease and colon cancer.
Scientists have discovered DNA-damaging molecules made by gut bacteria that may help explain why people with inflammatory bowel disease have higher rates of colorectal cancer than those without the condition.
Other gut bugs have been linked to IBD and colorectal cancer in the past, said Dr. Cynthia Sears , a professor of medicine and oncology at the Johns Hopkins University School of Medicine in Baltimore, who was not involved in the study. For example, select strains of Escherichia coli are associated with IBD and make a genotoxin called colibactin, which damages DNA and drives tumor growth in mice. The new study adds to our understanding of how other bacteria might contribute to these diseases.
The team grew each of these bacterial strains in a lab dish with DNA and identified 18 strains that damaged the genetic molecule. From these strains, the scientists identified individual molecules that the bacteria produced and tested which ones caused DNA damage.