Determinants of formation of aflatoxin-albumin adducts: A seven-township study in Taiwan

Columbia University, New York, New York, United States
British Journal of Cancer (Impact Factor: 4.84). 11/2002; 87(9):966-70. DOI: 10.1038/sj.bjc.6600584
Source: PubMed


Dietary exposure to aflatoxins is one of the major risk factors for hepatocellular carcinoma. Individual susceptibility to aflatoxin-induced hepatocarcinogenesis may be modulated by both genetic and environmental factors affecting metabolism. A cross-sectional study was performed to evaluate determinants of the formation of aflatoxin covalently bound to albumin (AFB1-albumin adducts). A total of 474 subjects who were free of liver cancer and cirrhosis and were initially selected as controls for previous case–control studies of aflatoxin-induced hepatocarcinogenesis in Taiwan, were employed in this study. Aflatoxin-albumin adducts were determined by competitive enzyme-linked immunosorbent assay, hepatitis B surface antigen and antibodies to hepatitis C virus by enzyme immunoassay, as well as genotypes of glutathione S-transferase M1-1 and T1-1 by polymerase chain reaction. The detection rate of AFB1-albumin adducts was significantly higher in males (42.5%) than in females (21.6%) (multivariate-adjusted odds ratio=2.6, 95% confidence interval=1.4–5.0). The formation of detectable albumin adducts was moderately higher in hepatitis B surface antigen carriers (42.8%) than in non-carriers (36.6%) (multivariate-adjusted odds ratio=1.4, 95% confidence interval=1.0–2.1). In addition, the detection rate of AFB1-albumin adducts tended to increase with the increasing number of null genotypes of glutathione S-transferase M1-1 and glutathione S-transferase T1-1. In conclusion, this cross-sectional study has assessed the relative contributions of environmental exposure and host susceptibility factors in the formation of AFB1-albumin adducts in a well characterised Chinese adult population. This study further emphasises the necessity to reduce aflatoxin exposure in people living in an area endemic for chronic hepatitis B virus infection.
British Journal of Cancer (2002) 87, 966–970. doi:10.1038/sj.bjc.6600584
© 2002 Cancer Research UK

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    • "AFs are responsible for a wide range of pathological abnormalities in humans and animals. Aflatoxin-albumin adduct (AFB1/Alb); a biomarker for aflatoxin exposure, was found to be higher in the serum of individuals at risk for hepatocellular carcinoma, thus, indicating its importance in human health and diseases (Sun et al., 2002). "
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