Research on Gut Microbiota-Derived Secondary Bile Acids in Cancer Progression

The interaction between gut microbiota-derived metabolites and the body plays a significant role in the occurrence and development of cancer. Secondary bile acids (BAs) are the important products produced from gut microbial fermentation of primary BAs, mainly deoxycholic acid (DCA) and lithocholic acid (LCA). In the gut, they can influence the structure of the microbial communities. Several studies have demonstrated that secondary BAs, as signaling molecules, can activate a variety of signaling pathways. They can inhibit the apoptosis of cancer cells, induce the progression of cancer cell cycles, enhance the ability of metastasis and invasion of cancer cells, and promote the transformation of cells into cancer stem cells (CSCs). Moreover, secondary BAs promote cancer by regulating the function of immune cells. Therefore, targeted manipulation of gut microbial and secondary BAs has the potential to be developed as for treatment and prevention of various cancers.