title: DNA adduct formation in human hepatoma cells treated with 3-nitrobenzanthrone: analysis by the (32)P-postlabeling method.
abstract: 3-Nitrobenzanthrone (3-nitro-7H-benz[d,e]anthracen-7-one, 3-NBA) is a powerful mutagen and a suspected human carcinogen existing in diesel exhaust and airborne particulates. Recently, one of the major presumed metabolites of 3-NBA, 3-aminobenzanthrone (3-ABA), was detected in human urine samples. Here we analyzed DNA adducts formed in 3-NBA-exposed human hepatoma HepG2 cells by a (32)P-postlabeling/thin layer chromatography (TLC) method and a (32)P-postlabeling/polyacrylamide gel electrophoresis (PAGE) method. With HepG2 cells exposed to 3-NBA (0.36-36.4 microM) for 3h, we obtained three spots or bands corresponding to adducted nucleotides. Two were assigned as 2-(2'-deoxyadenosin-N(6)-yl)-3-aminobenzanthrone-3'-phosphate (dA3'p-N(6)-C2-ABA) and 2-(2'-deoxyguanosin-N(2)-yl)-3-aminobenzanthrone-3'-phosphate (dG3'p-N(2)-C2-ABA), with identical mobilities to those of synthetic standards on PAGE analysis. The chemical structure of the substance corresponding to the other spot or band could not be identified. Quantitative analyses revealed that the major adduct was dA3'p-N(6)-C2-ABA and its relative adduct labeling (RAL) value at 36.4 microM of 3-NBA was 200.8+/-86.1/10(8)nucleotide.
authors: Frontier Science Innovation Center, Osaka Prefecture University, Osaka, Japan.
authors: Takaharu
authors: T
authors: Kanno
authors: Masanobu
authors: M
authors: Kawanishi
authors: Takeji
authors: T
authors: Takamura-Enya
authors: Volker M
authors: VM
authors: Arlt
authors: David H
authors: DH
authors: Phillips
authors: Takashi
authors: T
authors: Yagi
mesh_terms: D001551:Benz(a)Anthracenes / Q000494:pharmacology*; D006528:Carcinoma, Hepatocellular / Q000235:genetics*; D045744:Cell Line, Tumor; D002855:Chromatography, Thin Layer / Q000379:methods; D018736:DNA Adducts / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics*; D010761:Phosphorus Radioisotopes
chemical_list: D001551:Benz(a)Anthracenes; D018736:DNA Adducts; D010761:Phosphorus Radioisotopes; C117220:3-nitrobenzanthrone