Mechanism of Probiotic Action in Anticancer Immunity

Gut microbiota plays a significant role in human physiology which includes metabolism, nutrition uptake and immune responses. The imbalance of gut microbiota leads to various disorders or diseases like inflammatory bowel disease, infectious diseases, cancer and obesity. Cancer is one of the major health problems worldwide. Moreover, colorectal cancer (CRC) is the most common cancer in humans which is considered the fourth leading health problem worldwide. The role of probiotics in the regulation of CRC includes enhancement of immune barrier function, intestinal immune state, inhibition of enzymatic activity, cell proliferation and apoptosis, redox homeostasis, and modifying the composition of intestinal microbiota. It can be treated using chemotherapy, radiotherapy, or surgical eradication. However, these treatments may cause the demolition of the intestinal mucosal barrier system as well as dysfunction of the immune system in cancer patients. Hence, biotherapeutic drugs are used along with probiotics and their metabolites viz. polysaccharides, short-chain fatty acids, and inhibitory compounds like proteins and other substances to treat cancer. Lactobacillus rhamnosus GG (LGG) is a widely used probiotic strain in oncology. Also, it has been proven to exert beneficial effects on cancer patients after anticancer therapy. Therapeutic potential of the gut microbiome in cancer treatment via the administration of probiotic supplementations is being investigated using several clinical studies. Probiotic-incorporated biotheraupetic drugs are considered an alternative medicine for various types of cancer. The effectiveness of biotheraupetic drugs mainly depends on the dosage of probiotic strain and their exposure time. However, the mechanism behind the role of probiotics in cancer immunity is unclear so far. The present work summarizes the action of probiotics in anticancer immunity.