Antiproliferative Effects of Probiotics

Abstract

Probiotics are defined as live microorganisms that confer health benefits on the host when consumed in adequate amounts. They maintain proper microbial balance in gastrointestinal tract by strain-specific health-promoting activities like their antimicrobial, immunomodulation, anti-inflammatory, and anticarcinogenic attributes. A number of reports on anticarcinogenic effects exerted by probiotics against various types of cancer are available in literature. The anticarcinogenic properties of probiotics have been reported in various cancers and are attributable to a number of mechanisms at molecular level. The mechanisms underlying anti-cancerous effect include enhanced immune response in host, probiotic binding of potential carcinogens and their degradation, changes in the intestinal microflora, secretion of antitumorigenic compounds by probiotics in the colon leading to metabolic changes of colonic microflora, alteration in physicochemical environment of the colon, etc. The studies have been reviewed as to the in vivo and in vitro mechanisms underlying the antiproliferative effects exerted by probiotic lactic acid bacteria (LABs). However, for the therapy to reach the clinic, research in larger datasets needs to be carried out taking into consideration strain specificity of the effective probiotic or derivatives and their effect on the microbiome of the patients along with envisaged side effects. Further to establish the precise mechanisms by which LAB and its various entities inhibit cancer, carefully designed epidemiological studies are required. It purports to be a field which can yield novel drug entities with few or no side effects.