Synergism in actions of HBV with aflatoxin in cancer development.

Aflatoxin B1 (AFB1) is a fungal metabolite found in animal feeds and human foods. It is one of the most toxic and carcinogenic of aflatoxins and is classified as a Group 1 carcinogen. Dietary exposure to AFB1 and infection with chronic Hepatitis B Virus (HBV) make up two of the major risk factors for hepatocellular carcinoma (HCC). These two major risk factors raise the probability of synergism between the two agents. This review proposes some collaborative molecular mechanisms underlying the interaction between AFB1 and HBV in accelerating or magnifying the effects of HCC. The HBx viral protein is one of the main viral proteins of HBV and has many carcinogenic qualities that are involved with HCC. AFB1, when metabolized by CYP450, becomes AFB1-exo-8,9-epoxide (AFBO), an extremely toxic compound that can form adducts in DNA sequences and induce mutations. With possible synergisms that exist between HBV and AFB1 in mind, it is best to treat both agents simultaneously to reduce the risk by HCC.