Inflammation-Modulating Effect of Butyrate in the Prevention of Colon Cancer by Dietary Fiber

The intestinal microbiota plays key roles in human health, and adverse dysbiosis shifts of the microbiota have been associated with chronic diseases, including large bowel cancer. High-fiber diets may reduce the risk for large bowel cancer in association with gut microbiota modulation and butyrate production. Butyrate can inhibit histone deacetylases and associated signaling pathways in cultured cancer cells, promoting cancer cell apoptosis. However, butyrate has prevented colon cancer through the regulation of immune homeostasis rather than histone deacetylases inhibition. It could be important to further examine the pathways of how butyrate encourages immune system changes. We posited that butyrate-activated T-regulatory cells block proinflammatory T cells and thus reduce proinflammatory cytokine production; these cytokines increase cell proliferation and cell survival, the 2 most important cancer cell characteristics. Butyrate can exert anticancer effects through inhibition of multiple signaling pathways. It is possible that a low concentration of butyrate could modulate the immune system before other pathways to exert an anticancer effect. Increasing the concentration of butyrate in the intestines may produce a synergistic inhibitory signaling pathway response and an anti-inflammatory effect.