Metabiotics in Colorectal Cancer: Crosstalk Between Gut Microbiota and Host Pathology

After an extensive research and successful commercialization of probiotics in the past three decades, some scepticism regarding their safety and reproducibility of therapeutic advantage paved the way for “metabiotics”. The name metabiotics is a portmanteau created from the terms metabolites and probiotics. Also known as parabiotics and postbiotics, metabiotics are components of probiotic microorganisms and/or their metabolites with a determined chemical structure, which have been reported to be effective in the prevention and treatment of colorectal cancer (CRC). The main components of metabiotics are short-chain fatty acids (SCFAs), peptides, peptidoglycan-derived muropeptides, enzymes, polysaccharides, vitamins, teichoic acids, proteins and plasmalogens. Metabiotics help in the maintenance of GIT homeostasis and lead to proliferation of the healthy bacteria, which in turn reduces the levels of enzymes that are responsible for conversion of pro-carcinogens to carcinogens. Some components of metabiotics, specifically, SCFAs, have the ability to recognize cancer cells and de-repress the epigenetically silenced genes in them. The chemoprotective enzymes, secretory glycoproteins, certain exopolysaccharides and SCFAs all possess anti-mutagenic properties and exert a prophylactic effect against colorectal cancer. Apart from this, these components regulate the immune function and downregulate the inflammatory mediators, the most prominent causative factor in the development of CRC. Metabiotics have also demonstrated the antiproliferative effects and have been reported to increase the gut membrane integrity. This chapter discusses the potential of metabiotics as an effective strategy for prophylaxis or therapeutic option in treatment of CRC.