The Crucial Roles of Diet, Microbiota, and Postbiotics in Colorectal Cancer.

The link between diet, gut microbiota, and colorectal cancer has been established primarily as a relationship rather than a cause-effect relationship. The gut microbiota can convert gastrointestinal tract and dietary factors into either onco-metabolites or tumor suppressor metabolites. There is serious dysbiosis in the microbiota in colorectal cancer. Postbiotics appear to be promising agents in the prevention and treatment of colorectal cancer. It has been shown that various postbiotics can selectively induce apoptosis in CRC, inhibit cell proliferation, growth, invasion, and migration, modulate the immune system, suppress carcinogenic signaling pathways, maintain intestinal epithelial integrity, and have a synergistic effect with chemotherapy drugs. However, it is also reported that some postbiotics are ineffective and may be risky in terms of safety profile in some patients. Many issues need to be researched about postbiotics. Large-scale, randomized, double-blind clinical studies are needed.