Chemoprevention of hepatic cancer in aflatoxin endemic areas

Hepatocellular carcinoma is one of the most common cancers worldwide. Infection with hepatitis B virus and exposure to aflatoxins in the diet act synergistically to amplify risk. Although primary prevention, based on vaccination and avoiding exposure to these agents, is an appealing option, such strategies will require considerable investment of time and resources to be successful. In the economically developing world-where the burden of liver cancer is highest-immediate, practical approaches are essential. So, targeted chemoprevention might be most appropriate for the present generation of individuals at risk. Experimentally, aflatoxin-induced hepatocarcinogenesis can be inhibited by over a score of different chemopreventive agents with multiple mechanisms of action. This chapter highlights the findings of randomized clinical trials conducted in individuals exposed to dietary aflatoxins and at high risk of development of liver cancer. Several preventive interventions, both primary and secondary in approach, have succeeded in modulating levels of aflatoxin biomarkers in the study participants in manners consonant with protection. Although pharmacological approaches establish proof-of-principle and help identify key molecular targets for interventions, food-based approaches that also use these molecular targets may be the most practical for widespread application in high-risk populations.