Does aflatoxin B1 play a role in the etiology of hepatocellular carcinoma in the United States?
Previous research showed that risk factors associated with hepatocellular carcinoma (HCC) include infection with hepatitis B (HBV) and hepatitis C (HCV) viruses, exposure to aflatoxin B1 (AFB1), and liver cirrhosis, due primarily to alcohol consumption. To determine whether AFB1 may play a role in HCC in the United States, a search for AFB1 adducts and p53 alterations, potentially induced by AFB1, was conducted in the United States in 23 HCC patients with available tissue samples. The presence of AFB1 tumor-DNA and -serum lysine adducts and mutant p53 product was determined by immunoassays and codon 249 p53 mutation by restriction enzyme analysis. HBV and HCV serology and serum HBV-DNA were also determined. Thirteen patients were positive for HBV by HBs antigen or anti-HBc antigen or by polymerase chain reaction for HBV-DNA sequences. Nine patients were free of HBV and HCV markers; 5 of 22 sera tested were anti-HCV positive. p53 Protein expression, determined by immunohistochemical sta