Microbial bile acids: Immunomodulatory signals in the tumor microenvironment.

Microbial metabolites can act as systemic signals that connect gut dysbiosis to tumor immune remodeling. Recently, Li et al. showed that gut microbiota-derived deoxycholic acid activates the farnesoid X receptor-nuclear factor κB-interleukin-6 axis in breast cancer cells, promoting the recruitment of granulocytic myeloid-derived suppressor cells, T helper polarization, and tumor progression. These findings offer new insights into microbial bile acid signaling in the tumor microenvironment.