The Gut Microbiome: A New Player in Breast Cancer Metastasis

Abstract There is increasing interest in the role of the gut microbiome in health and disease, and a number of observational and in vitro studies have suggested it may play a role in breast cancer development and progression. Buchta Rosean and colleagues present the first functional evidence that a preexisting disturbance in the gut microbiome leads to increased breast cancer cell metastasis in a mouse model. This discovery places the gut microbiome as a new player in breast cancer metastasis; however, further studies are required to determine the relevance of the findings in this mouse model to human disease. A better understanding of the relationship between the bacterial ecosystem of the gut and progression of breast cancer has enormous potential for improving treatment outcomes for patients with breast cancer. See related article by Buchta Rosean et al., p. 3662