Possible mechanisms of cancer prevention by nicotinamide.

Nicotinamide (NAM) is a precursor of vitamin B3 commonly sold over the counter as a nutritional supplement with anti-aging properties. Accumulating preclinical evidence indicates that NAM also mediates oncopreventive effects against a variety of neoplasms. Supporting the translational relevance of dietary NAM supplementation, results from a Phase 3 randomized clinical trial have demonstrated that oral NAM was safe and efficiently reduced the incidence of new non-melanoma skin cancers and actinic keratosis amongst high-risk individuals. However, the molecular and cellular mechanisms that underlie this ability of NAM to delay carcinogenesis remain to be clarified, as discussed in this short review.