Natural products as inhibitors of carcinogenesis

Background: Although carcinogenesis and cancer have been studied intensively for > 50 years, the rates of cancer incidence and mortality remain high. The most successful approach for reducing these rates has been primary prevention. For individuals at a high risk of developing cancer owing to certain genetic, environmental and occupational factors, cancer chemoprevention is a logical approach. Objective: This review discusses natural products as inhibitors of carcinogenesis. Conclusion: Natural product chemopreventive agents are inherently biologically active and have been demonstrated to prevent and reverse the carcinogenic process in a pleiotropic manner. Derivatives of compounds discovered by screening natural products for chemopreventive agents have shown efficacy in clinical trials. Despite the obstacles that must be overcome before chemopreventive drugs become an integral component of standard medical practice for cancer prophylaxis, there is vast potential for significant improvement in cancer morbidity and mortality through the use of natural product chemopreventive drugs.