Gut Microbe may Hold Potential in Treating Breast Cancer by Angela Mohan on January 7, 2021 at 3:45 PM Colon microbes may play a role in the development of some breast cancers, according to new research from investigators with the Johns Hopkins Kimmel Cancer Center and its Bloomberg~Kimmel Institute for Cancer Immunotherapy. In a series of laboratory experiments, researchers discovered that when enterotoxigenic Bacteroides fragilis (ETBF) was introduced to the guts or breast ducts of mice, it always induced growth and metastatic progression of tumor cells. A description of the work is published in the journal Cancer Discovery. While microbes are known to be present in body sites such as the gastrointestinal tract, nasal passages and skin, breast tissue was considered sterile until recently, says senior study author Dipali Sharma, Ph.D., a professor of oncology at Johns Hopkins Medicine.