Role of intestinal microbiota in colon cancer prevention.

Environmental and hereditary factors, together with lifestyle, are important factors in colon cancer development. Considering the increasing incidence of this disease, especially in the developed western world, the last decade has seen much attention directed towards understanding possible prevention strategies. Efforts to study the intestinal microbiota and its interaction with the host have underlined that disbiosis in colonic bacterial composition is a risk factor for colon cancer. Modulation of the composition of intestinal microbiota through the use of probiotic, prebiotic and synbiotic products could therefore represent a strategy for prevention of cancer development. The mechanisms underlying the probiotic-prebiotic anticarcinogenic effect involve a combination of events: e.g. binding of mutagens, suppression of bacteria that convert procarcinogens into carcinogens, immune system stimulation, and a reduction in the level of certain intestinal bacterial enzymes that promote carcinogen formation.