Human liver microsomal cytochrome P-450 enzymes involved in the bioactivation of procarcinogens detected by umu gene response in Salmonella typhimurium TA 1535/pSK1002.

A total of 57 procarcinogens was examined for induction of umu gene response in the chimeric plasmid pSK1002, carried in Salmonella typhimurium TA 1535, after incubation with a series of human liver microsomal preparations which had been selected on the basis of characteristic levels of individual cytochrome P-450 (P-450) enzymes. The 18 most active compounds were selected and further analyzed using the umu gene response and correlative studies with a larger number of microsomal preparations, enzyme reconstitution studies involving purified enzymes, immunochemical inhibition, and patterns of stimulation and inhibition of catalytic activity by 7,8-benzoflavone. The results collectively indicate that 16 of these 18 most potent genotoxins examined are activated primarily either by P-450NF (the nifedipine oxidase) or P-450PA (the phenacetin O-deethylase). P-450NF appears to be the major enzyme involved in the bioactivation of aflatoxin B1, aflatoxin G1, sterigmatocystin, trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene, 6-aminochrysene, and tris-(2,3-dibromopropyl)phosphate in human liver. P-450PA appears to be the major enzyme involved in the bioactivation of 2-amino-3-methylimidazo[4,5-f]quinoline, 2-amino-3,5-dimethylimidazo[4, 5-f]quinoline, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, 2-aminoanthracene, 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole, 2-aminofluorene, 2-acetylaminofluorene, 4-aminobiphenyl, 3-amino-1-methyl-5H-pyrido[4,3-b] indole, and 2-aminodipyrido[1,2-a:3',2'-d]imidazole. More than one enzyme appears to contribute significantly to the bioactivation of the other two compounds examined, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b] indole and 6-nitrochrysene. The literature suggests that the two human liver P-450s involved in activation of these 16 procarcinogens are highly inducible by barbiturates, macrolide antibodies, and certain steroids (P-450NF) and by smoking and ingestion of charcoal-containing food (P-450PA); noninvasive assays are available to monitor the function of both P-450NF and P-450PA.

[1]  J. Omichinski,et al.  Metabolism in vitro of tris(2,3-dibromopropyl)-phosphate: oxidative debromination and bis(2,3-dibromopropyl)phosphate formation as correlates of mutagenicity and covalent protein binding. , 1984, Biochemical pharmacology.

[2]  O. Pelkonen,et al.  The effect of cigarette smoking on 7-ethoxyresorufin O-deethylase and other monooxygenase activities in human liver: analyses with monoclonal antibodies. , 1986, British journal of clinical pharmacology.

[3]  A. Conney,et al.  Induction of microsomal enzymes by foreign chemicals and carcinogenesis by polycyclic aromatic hydrocarbons: G. H. A. Clowes Memorial Lecture. , 1982, Cancer research.

[4]  P. Watkins,et al.  Complete cDNA sequence of a cytochrome P-450 inducible by glucocorticoids in human liver. , 1986, Proceedings of the National Academy of Sciences of the United States of America.

[5]  M. J. Coon,et al.  Specificity in the activation and inhibition by flavonoids of benzo[a]pyrene hydroxylation by cytochrome P-450 isozymes from rabbit liver microsomes. , 1981, The Journal of biological chemistry.

[6]  D. Breimer,et al.  Lack of bimodality in nifedipine plasma kinetics in a large population of healthy subjects. , 1988, Biochemical pharmacology.

[7]  P. Beaune,et al.  Purification and characterization of six cytochrome P-450 isozymes from human liver microsomes. , 1983, Biochemistry.

[8]  P. Srivastava,et al.  Expression of a human liver cytochrome P-450 protein with tolbutamide hydroxylase activity in Saccharomyces cerevisiae. , 1989, Biochemistry.

[9]  J. Halpert,et al.  Evidence for functional and structural multiplicity of pregnenolone-16 alpha-carbonitrile-inducible cytochrome P-450 isozymes in rat liver microsomes. , 1987, Biochemistry.

[10]  P. Watkins,et al.  Identification of an inducible form of cytochrome P-450 in human liver. , 1985, Proceedings of the National Academy of Sciences of the United States of America.

[11]  P. Thomas,et al.  Regulation of cytochrome P-450j, a high-affinity N-nitrosodimethylamine demethylase, in rat hepatic microsomes. , 1987, Biochemistry.

[12]  F. Guengerich,et al.  Purification and characterization of the human liver cytochromes P-450 involved in debrisoquine 4-hydroxylation and phenacetin O-deethylation, two prototypes for genetic polymorphism in oxidative drug metabolism. , 1985, The Journal of biological chemistry.

[13]  G. Wilkinson,et al.  Interaction of quinidine with anticonvulsant drugs. , 1976, The New England journal of medicine.

[14]  D. Nebert.  Genetic control of carcinogen metabolism leading to individual differences in cancer risk , 1978 .

[15]  P. Srivastava,et al.  Characterization of cDNAs, mRNAs, and proteins related to human liver microsomal cytochrome P-450 (S)-mephenytoin 4'-hydroxylase. , 1988, Biochemistry.

[16]  F. Guengerich,et al.  Cytochrome P-450- and flavin-containing monooxygenase-catalyzed formation of the carcinogen N-hydroxy-2-aminofluorene and its covalent binding to nuclear DNA. , 1982, Cancer research.

[17]  D. Nebert,et al.  Human P1-450 gene sequence and correlation of mRNA with genetic differences in benzo[a]pyrene metabolism. , 1985, Nucleic acids research.

[18]  N. Abraham,et al.  Purification and characterization of cytochrome P-450-dependent arachidonic acid epoxygenase from human liver. , 1988, The Journal of biological chemistry.

[19]  Makino Kozo,et al.  Cloning and characterization of the umu operon responsible for inducible mutagenesis in Escherichia coli , 1983 .

[20]  F. Guengerich.  Cytochrome P-450 enzymes and drug metabolism , 1987 .

[21]  M. Butler,et al.  Metabolic oxidation of the carcinogens 4-aminobiphenyl and 4,4'-methylene-bis(2-chloroaniline) by human hepatic microsomes and by purified rat hepatic cytochrome P-450 monooxygenases. , 1989, Cancer research.

[22]  N P Wray,et al.  Positive correlation between high aryl hydrocarbon hydroxylase activity and primary lung cancer as analyzed in cryopreserved lymphocytes. , 1982, Cancer research.

[23]  T. Shimada,et al.  Genotoxic and mutagenic activation of aflatoxin B1 by constitutive forms of cytochrome P-450 in rat liver microsomes. , 1987, Toxicology and applied pharmacology.

[24]  D. Waxman,et al.  17 beta-estradiol 2- and 4-hydroxylation catalyzed by rat hepatic cytochrome P-450: roles of individual forms, inductive effects, developmental patterns, and alterations by gonadectomy and hormone replacement. , 1986, Endocrinology.

[25]  P. Watkins,et al.  Identification of glucocorticoid-inducible cytochromes P-450 in the intestinal mucosa of rats and man. , 1987, The Journal of clinical investigation.

[26]  D W Nebert,et al.  P450 genes: structure, evolution, and regulation. , 1987, Annual review of biochemistry.

[27]  T. Shimada,et al.  Metabolic activation of environmental carcinogens and mutagens by human liver microsomes. Role of cytochrome P-450 homologous to a 3-methylcholanthrene-inducible isozyme in rat liver. , 1988, Biochemical pharmacology.

[28]  Jeffrey H. Miller.  Experiments in molecular genetics , 1972 .

[29]  F. Guengerich,et al.  Oxidation of quinidine by human liver cytochrome P-450. , 1986, Molecular pharmacology.

[30]  T. Shimada,et al.  Cytochrome P-450-mediated activation of procarcinogens and promutagens to DNA-damaging products by measuring expression of umu gene in Salmonella typhimurium TA1535/pSK1002. , 1987, Biochemical pharmacology.

[31]  F. Guengerich,et al.  Substrate specificity of human liver cytochrome P-450 debrisoquine 4-hydroxylase probed using immunochemical inhibition and chemical modeling. , 1985, Cancer research.

[32]  F. Guengerich,et al.  Purification of human liver cytochrome P-450 and comparison to the enzyme isolated from rat liver. , 1980, Archives of biochemistry and biophysics.

[33]  D. Grant,et al.  Biotransformation of caffeine, paraxanthine, theophylline, and theobromine by polycyclic aromatic hydrocarbon-inducible cytochrome(s) P-450 in human liver microsomes. , 1987, Drug metabolism and disposition: the biological fate of chemicals.

[34]  M. Hetzel,et al.  Metabolic oxidation phenotypes as markers for susceptibility to lung cancer , 1984, Nature.

[35]  P. Beaune,et al.  Isolation and sequence determination of a cDNA clone related to human cytochrome P-450 nifedipine oxidase. , 1986, Proceedings of the National Academy of Sciences of the United States of America.

[36]  D. Waxman,et al.  Regulation of rat hepatic cytochrome P-450: age-dependent expression, hormonal imprinting, and xenobiotic inducibility of sex-specific isoenzymes. , 1985, Biochemistry.

[37]  B. Ames,et al.  Detection of carcinogens as mutagens in the Salmonella/microsome test: assay of 300 chemicals. , 1975, Proceedings of the National Academy of Sciences of the United States of America.

[38]  G. Fisher,et al.  Isolation, purification, and properties of a unique form of cytochrome P-450 in microsomes of isosafrole-treated rats. , 1981, The Journal of biological chemistry.

[39]  A. Conney,et al.  Effect of charcoal-broiled beef on phenacetin metabolism in man. , 1976, Science.

[40]  A. Conney,et al.  Effect of cigarette smoking on phenacetin metabolism , 1974, Clinical pharmacology and therapeutics.

[41]  H. Gelboin,et al.  Phenotyping of cytochromes P-450 in human tissues with monoclonal antibodies. , 1982, Proceedings of the National Academy of Sciences of the United States of America.

[42]  T. Shimada,et al.  Human liver microsomal cytochrome P-450 mephenytoin 4-hydroxylase, a prototype of genetic polymorphism in oxidative drug metabolism. Purification and characterization of two similar forms involved in the reaction. , 1986, The Journal of biological chemistry.

[43]  L. Marnett,et al.  Inhibitors of cytochrome P-450-dependent arachidonic acid metabolism. , 1988, Archives of biochemistry and biophysics.

[44]  F. Guengerich,et al.  Estimation of isozymes of microsomal cytochrome P-450 in rats, rabbits, and humans using immunochemical staining coupled with sodium dodecyl sulfate-polyacrylamide gel electrophoresis. , 1982, Biochemistry.

[45]  J. Miners,et al.  Tolbutamide hydroxylation by human liver microsomes. Kinetic characterisation and relationship to other cytochrome P-450 dependent xenobiotic oxidations. , 1988, Biochemical pharmacology.

[46]  Y. Yasukochi,et al.  Some properties of a detergent-solubilized NADPH-cytochrome c(cytochrome P-450) reductase purified by biospecific affinity chromatography. , 1976, The Journal of biological chemistry.

[47]  P. Srivastava,et al.  Characterization of mRNA species related to human liver cytochrome P-450 nifedipine oxidase and the regulation of catalytic activity. , 1989, The Journal of biological chemistry.

[48]  M. J. Coon,et al.  The P450 superfamily: updated listing of all genes and recommended nomenclature for the chromosomal loci. , 1989, DNA.

[49]  F. Guengerich,et al.  Composition of cytochrome P-450 isozymes from hepatic microsomes of C57BL/6 and DBA/2 mice assessed by warfarin metabolism, immunoinhibition, and immunoelectrophoresis with anti-(rat cytochrome P-450). , 1984, European journal of biochemistry.

[50]  D. Ziegler,et al.  Flavin-containing monooxygenases: catalytic mechanism and substrate specificities. , 1988, Drug metabolism reviews.

[51]  R. Branch,et al.  Genetic predisposition to bladder cancer: ability to hydroxylate debrisoquine and mephenytoin as risk factors. , 1987, Cancer research.

[52]  F. Guengerich.  Roles of cytochrome P-450 enzymes in chemical carcinogenesis and cancer chemotherapy. , 1988, Cancer research.

[53]  P. Beaune,et al.  Comparison of monooxygenase activities and cytochrome P-450 isozyme concentrations in human liver microsomes. , 1986, Drug metabolism and disposition: the biological fate of chemicals.

[54]  F. Guengerich,et al.  Oxidation of 4-aryl- and 4-alkyl-substituted 2,6-dimethyl-3,5-bis(alkoxycarbonyl)-1,4-dihydropyridines by human liver microsomes and immunochemical evidence for the involvement of a form of cytochrome P-450. , 1987, Journal of medicinal chemistry.

[55]  F. Guengerich.  Characterization of human microsomal cytochrome P-450 enzymes. , 1989, Annual review of pharmacology and toxicology.

[56]  A. Y. Lu,et al.  Chapter 7 – Reactions Catalyzed by the Cytochrome P-450 System , 1980 .

[57]  B K Tang,et al.  Biotransformation of caffeine by microsomes from human liver. Kinetics and inhibition studies. , 1987, Biochemical pharmacology.

[58]  E C Miller,et al.  Searches for ultimate chemical carcinogens and their reactions with cellular macromolecules , 1981, Cancer.

[59]  B. Ames,et al.  Carcinogens are mutagens: a simple test system combining liver homogenates for activation and bacteria for detection. , 1973, Proceedings of the National Academy of Sciences of the United States of America.

[60]  F. Guengerich,et al.  Regulation of cytochrome P-450. Immunochemical quantitation of eight isozymes in liver microsomes of rats treated with polybrominated biphenyl congeners. , 1983, The Journal of biological chemistry.

[61]  F. Guengerich,et al.  Hepatic drug-metabolizing enzymes in primary and secondary tumors of human liver. , 1987, Cancer research.