Role of Human N-Acetyltransferase 2 Genetic Polymorphism on Aromatic Amine Carcinogen-Induced DNA Damage and Mutagenicity in a Chinese Hamster Ovary Cell Mutation Assay
Autor: | Raúl A. Salazar-González, Mark A. Doll, David W. Hein, William M. Pierce, Kristin J. Baldauf, J. Christopher States |
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Rok vydání: | 2019 |
Předmět: |
Epidemiology
DNA damage Base pair Arylamine N-Acetyltransferase Health Toxicology and Mutagenesis Mutagen CHO Cells 010501 environmental sciences medicine.disease_cause 01 natural sciences Article 03 medical and health sciences chemistry.chemical_compound Cricetulus Cricetinae medicine Aminobiphenyl Compounds Animals Humans Genetics (clinical) Carcinogen 030304 developmental biology 0105 earth and related environmental sciences chemistry.chemical_classification 0303 health sciences Fluorenes Polymorphism Genetic Chemistry Mutagenicity Tests Chinese hamster ovary cell Aromatic amine Acetylation Molecular biology 4-Aminobiphenyl Mutagenesis Carcinogens DNA DNA Damage |
Zdroj: | Environ Mol Mutagen |
ISSN: | 1098-2280 |
Popis: | Carcinogenic aromatic amines such as 4-aminobiphenyl (ABP) and 2-aminofluorene (AF) require metabolic activation to form electrophilic intermediates that mutate DNA leading to carcinogenesis. Bioactivation of these carcinogens includes N-hydroxylation catalyzed by CYP1A2 followed by O-acetylation catalyzed by arylamine N-acetyltransferase 2 (NAT2). To better understand the role of NAT2 genetic polymorphism in ABP- and AF-induced mutagenesis and DNA damage, nucleotide excision repair-deficient (UV5) Chinese hamster ovary (CHO) cells were stably transfected with human CYP1A2 and either NAT2*4 (rapid acetylator) or NAT2*5B (slow acetylator) alleles. ABP and AF both caused significantly (P < 0.001) greater mutagenesis measured at the hypoxanthine phosphoribosyl transferase (hprt) locus in the UV5/CYP1A2/NAT2*4 acetylator cell line compared to the UV5, UV5/CYP1A2, and UV5/CYP1A2/NAT2*5B cell lines. ABP- and AF-induced hprt mutant cDNAs were sequenced and over 80% of the single-base substitutions were at G:C base pairs. DNA damage also was quantified by γH2AX in-cell western assays and by identification and quantification of the two predominant DNA adducts, N-(deoxyguanosin-8-yl)-4-aminobiphenyl (dG-C8-ABP) and N-(deoxyguanosin-8-yl)-2-aminofluorene (dG-C8-AF) by liquid chromatography-mass spectrometry. DNA damage and adduct levels were dose-dependent, correlated highly with levels of hprt mutants, and were significantly (P < 0.0001) greater in the UV5/CYP1A2/NAT2*4 rapid acetylator cell line following treatment with ABP or AF as compared to all other cell lines. Our findings provide further clarity on the importance of O-acetylation in CHO mutagenesis assays for aromatic amines. They provide evidence that NAT2 genetic polymorphism modifies aromatic amine-induced DNA damage and mutagenesis that should be considered in human risk assessments following aromatic amine exposures. Environ. Mol. Mutagen. 61:235-245, 2020. © 2019 Wiley Periodicals, Inc. |
Databáze: | OpenAIRE |
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