Identification of 7,12-dimethylbenz[a]anthracene Metabolites That Lead to Mutagenesis in Mammalian Cells

Overview

Journal Proc Natl Acad Sci U S A

Specialty Science

Date 1979 Feb 1

PMID 106395

Citations 6

Authors

E Huberman

M W Chou

S K Yang

Affiliations

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Abstract

The mutagenicity of 7,12-dimethylbenz[a]-anthracene (DMBA) and 11 of its enzymatically derived metabolites was tested with Chinese hamster V79 cells for identification of mutagenic metabolites. The metabolites consisted of 7-hydroxymethyl-12-methylbenz[a]anthracene, 7-methyl-12-hydroxymethylbenz[a]anthracene, 7,12-dihydroxymethylbenz[a]anthracene, three trans-3,4-diols, two trans-5,6-diols, and three trans-8,9-diols, all of which derived from DMBA or from the hydroxymethyl derivatives. Mutations were characterized by resistance to ouabain and 6-thioguanine. None of the tested metabolites were mutagenic in V79 cells, which do not metabolize polycyclic aromatic hydrocarbons. Therefore, mutagenesis in the V79 cells was tested in the presence of golden hamster cells capable of metabolizing polycyclic aromatic hydrocarbons (cell-mediated assay). In this assay, DMBA, 7-hydroxymethyl-12-methylbenz[a]anthracene, 7-methyl-12-hydroxymethylbenz[a]anthracene, and their trans3,4-diols were mutagenic for both genetic markers, and the mutagenic response increased as a function of the hydrocarbon dose. All other metabolites were either inactive or showed up to a 4-fold higher mutation frequency than the untreated V79 cells for ouabain and 6-thioguanine resistance. The DMBA-trans-3,4-diol was the only metabolite that was more active than DMBA itself; at 0.05 muM it was 6-8 times more active than DMBA itself; at 0.05 muM it was 6-8 times more active than DMBA in inducing both ouabain and 6-thioguanine resistance. This diol was mutagenic at a dose as low as 0.01 muM. Mutagenesis by DMBA and the trans-3,4-diols was inhibited by 7,8-benzoflavone, an inhibitor of mixed-function oxidases. Analysis of DMBA metabolism in intact golden hamster cells indicated that DMBA-trans-3,4-diol is one of the major metabolites produced. Our results therefore suggest that DMBA-trans-3,4-diol may be metabolized to a diol-epoxide, presumably the trans-3,4-diol-1,2-epoxide, which may be a major reactive metabolite responsible for DMBA mutagenicity in mammalian cells.

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References

Chou M, Yang S . Identification of four trans-3,4-dihydrodiol metabolites of 7,12-dimethylbenz[a]anthracene and their in vitro DNA-binding activities upon further metabolism. Proc Natl Acad Sci U S A. 1978; 75(11):5466-70. PMC: 392985. DOI: 10.1073/pnas.75.11.5466. View

Huberman E, Mager R, Sachs L . Mutagenesis and transformation of normal cells by chemical carcinogens. Nature. 1976; 264(5584):360-1. DOI: 10.1038/264360a0. View

McCann J, Choi E, Yamasaki E, Ames B . Detection of carcinogens as mutagens in the Salmonella/microsome test: assay of 300 chemicals. Proc Natl Acad Sci U S A. 1975; 72(12):5135-9. PMC: 388891. DOI: 10.1073/pnas.72.12.5135. View

Huberman E, Sachs L . Mutability of different genetic loci in mammalian cells by metabolically activated carcinogenic polycyclic hydrocarbons. Proc Natl Acad Sci U S A. 1976; 73(1):188-92. PMC: 335866. DOI: 10.1073/pnas.73.1.188. View

Huberman E, Sachs L, Yang S, Gelboin V . Identification of mutagenic metabolites of benzo(a)pyrene in mammalian cells. Proc Natl Acad Sci U S A. 1976; 73(2):607-11. PMC: 335960. DOI: 10.1073/pnas.73.2.607. View

Yang S, McCourt D, Roller P, Gelboin H . Enzymatic conversion of benzo(a)pyrene leading predominantly to the diol-epoxide r-7,t-8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene through a single enantiomer of r-7, t-8-dihydroxy-7,8-dihydrobenzo(a)pyrene. Proc Natl Acad Sci U S A. 1976; 73(8):2594-8. PMC: 430694. DOI: 10.1073/pnas.73.8.2594. View

King H, Osborne M, Beland F, Harvey R, Brookes P . (+/-)-7alpha,8beta-dihydroxy-9beta,10beta-epoxy-7,8,9,10-tetrahydrobenzo(a)-pyrene is an intermediate in the metabolism and binding to DNA of benzo(a)pyrene. Proc Natl Acad Sci U S A. 1976; 73(8):2679-81. PMC: 430711. DOI: 10.1073/pnas.73.8.2679. View

Thakker D, Yagi H, Lu A, Levin W, Conney A . Metabolism of benzo[a]pyrene: conversion of (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene to highly mutagenic 7,8-diol-9,10-epoxides. Proc Natl Acad Sci U S A. 1976; 73(10):3381-5. PMC: 431118. DOI: 10.1073/pnas.73.10.3381. View

HEIDELBERGER C . Chemical carcinogenesis. Annu Rev Biochem. 1975; 44:79-121. DOI: 10.1146/annurev.bi.44.070175.000455. View

10.

Malaveille C, Bartsch H, Grover P, Sims P . Mutagenicity of non-K-region diols and diol-epoxides of benz(a)anthracene and benzo(a)pyrene in S. typhimurium TA 100. Biochem Biophys Res Commun. 1975; 66(2):693-700. DOI: 10.1016/0006-291x(75)90565-3. View

11.

van Zeeland A, Simons J . The effect of calf serum on the toxicity of 8-azaguanine. Mutat Res. 1975; 27(1):135-8. DOI: 10.1016/0027-5107(75)90283-3. View

12.

Cairns J . Mutation selection and the natural history of cancer. Nature. 1975; 255(5505):197-200. DOI: 10.1038/255197a0. View

13.

Newbold R, Brookes P . Exceptional mutagenicity of a benzo(a)pyrene diol epoxide in cultured mammalian cells. Nature. 1976; 261(5555):52-4. DOI: 10.1038/261052a0. View

14.

Huggins C, Grand L, Brillantes F . Mammary cancer induced by a single feeding of polymucular hydrocarbons, and its suppression. Nature. 1961; 189:204-7. DOI: 10.1038/189204a0. View

15.

Langenbach R, Freed H, Huberman E . Liver cell-mediated mutagenesis of mammalian cells by liver carcinogens. Proc Natl Acad Sci U S A. 1978; 75(6):2864-7. PMC: 392665. DOI: 10.1073/pnas.75.6.2864. View

16.

Barrett J, Tso P . Relationship between somatic mutation and neoplastic transformation. Proc Natl Acad Sci U S A. 1978; 75(7):3297-301. PMC: 392762. DOI: 10.1073/pnas.75.7.3297. View

17.

Chan G, Little J . Induction of ouabain-resistant mutations in C3H 10T1/2 mouse cells by ultraviolet light. Proc Natl Acad Sci U S A. 1978; 75(7):3363-6. PMC: 392776. DOI: 10.1073/pnas.75.7.3363. View

18.

Huberman E, Fogel M . Activation of carcinogenic polycyclic hydrocarbons in polyoma-virus-transformed cells as a prerequisite for polyoma virus induction. Int J Cancer. 1975; 15(1):91-8. DOI: 10.1002/ijc.2910150111. View

19.

Malaveille C, Tierney B, Grover P, Sims P, Bartsch H . High microsome-mediated mutagenicity of the 3,4-dihydrodiol of 7-methylbenz[a]anthracene in S. typhimurium TA 98. Biochem Biophys Res Commun. 1977; 75(2):427-33. DOI: 10.1016/0006-291x(77)91060-9. View

20.

Selkirk J . Benzo[a]pyrene carcinogenesis: a biochemical selection mechanism. J Toxicol Environ Health. 1977; 2(6):1245-58. DOI: 10.1080/15287397709529527. View