title: Determinants of formation of aflatoxin-albumin adducts: a seven-township study in Taiwan.
abstract: 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.
authors.affiliation: School of Public Health, National Defense Medical Center, School of Public Health, No. 161, Section 6, Min-Chuan East Road, Taipei 114, Taiwan, Republic of China. sunca@ndmctsgh.edu.tw
authors.forename: C-A
authors.initials: CA
authors.lastname: Sun
authors.forename: D-M
authors.initials: DM
authors.lastname: Wu
authors.forename: L-Y
authors.initials: LY
authors.lastname: Wang
authors.forename: C-J
authors.initials: CJ
authors.lastname: Chen
authors.forename: S-L
authors.initials: SL
authors.lastname: You
authors.forename: R M
authors.initials: RM
authors.lastname: Santella
mesh_terms: D000328:Adult; D016604:Aflatoxin B1 / Q000009:adverse effects; D000348:Aflatoxins / Q000096:biosynthesis*; D000418:Albumins / Q000096:biosynthesis*; D006528:Carcinoma, Hepatocellular / Q000139:chemically induced / Q000378:metabolism* / Q000821:virology; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000009:adverse effects; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005982:Glutathione Transferase / Q000378:metabolism; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D018937:Hepatitis C Antibodies / Q000032:analysis; D006801:Humans; D008103:Liver Cirrhosis / Q000139:chemically induced / Q000378:metabolism* / Q000821:virology; D008113:Liver Neoplasms / Q000139:chemically induced / Q000378:metabolism* / Q000821:virology; D008297:Male; D008875:Middle Aged; D013624:Taiwan / Q000453:epidemiology
chemical_list: D016604:Aflatoxin B1; D000348:Aflatoxins; D000418:Albumins; D005982:Glutathione Transferase; D006514:Hepatitis B Surface Antigens; D018937:Hepatitis C Antibodies; C098408:aflatoxin-albumin adduct; C413545:glutathione S-transferase T1