Roles of human liver cytochrome P4502C and 3A enzymes in the 3-hydroxylation of benzo(a)pyrene.

The major oxidation product of the classic polycyclic hydrocarbon carcinogen benzo(a)pyrene [B(a)P] is 3-hydroxy B(a)P. Numerous studies have been concerned with the measurement of B(a)P 3-hydroxylation activity in experimental animals and human tissues. Although human liver is the main site of this reaction, systematic studies had not been carried out to define the roles of individual cytochrome P-450 (P-450) enzymes involved. Purified human P4502C8 and P4503A4 showed appreciable catalytic activity; purified human P4501A2 and yeast recombinant (human) P4502C9 and P4502C10 had less activity. No B(a)P 3-hydroxylation activity was observed with purified human P4502A6, P4502D6, P45602E1, or P4502CMP. When microsomes prepared from different human liver samples were compared, B(a)P 3-hydroxylation activity was well correlated with nifedipine oxidation (a P4503A4 marker) but not markers of other P-450s, including tolbutamide hydroxylation (P4502C9 and 2C10), chlorzoxazone 6-hydroxylation (P4502E1), (S)-mephenytoin 4'-hydroxylation (P4502CMP), and coumarin 7-hydroxylation (P4502A6). In three of the liver microsomal samples with relatively high B(a)P 3-hydroxylation activity, immunoinhibition was observed with anti-P4503A greater than anti-P4502C (and no inhibition with several other antibodies). The selective chemical inhibitors gestodene and troleandomycin (P4503A enzymes) and sulfaphenazole (P4502C enzymes) reduced the B(a)P 3-hydroxylation activity of the more active microsomal preparations to rates seen in the preparations with low activity. This residual activity (and most of the activity in the low activity samples) was refractory to all of the chemical inhibitors and antibodies. The addition of 7,8-benzoflavone dramatically stimulated B(a)P 3-hydroxylation in all of the microsomal samples (and also stimulated purified P4503A4), arguing against an important role for P4501A1 or P4501A2. We conclude that roles of human P-450 enzymes for B(a)P 3-hydroxylation follow the order P4503A4 greater than or equal to P4502C8 greater than P4502C9/10 in human liver and that the other P-450s examined here do not have major roles. P4502C8 and P4502CMP (but not P4503A4) were found to activate B(a)P to products genotoxic in Salmonella typhimurium; this pathway would appear to involve products other than 3-hydroxy B(a)P and B(a)P 7,8-dihydrodiols.

[1]  T. Shimada,et al.  Purification and characterization of human liver microsomal cytochrome P-450 2A6. , 1991, Molecular pharmacology.

[2]  U. Meyer,et al.  Polymerase chain reaction-directed identification, cloning, and quantification of human CYP2C18 mRNA. , 1991, Molecular pharmacology.

[3]  P. Srivastava,et al.  Separation of human liver microsomal tolbutamide hydroxylase and (S)-mephenytoin 4'-hydroxylase cytochrome P-450 enzymes. , 1991, Molecular pharmacology.

[4]  T. Shimada,et al.  Oxidation of toxic and carcinogenic chemicals by human cytochrome P-450 enzymes. , 1991, Chemical research in toxicology.

[5]  M. J. Coon,et al.  The P450 superfamily: update on new sequences, gene mapping, and recommended nomenclature. , 1991, DNA and cell biology.

[6]  R. Thurman,et al.  The liver plays a central role in the mechanism of chemical carcinogenesis due to polycyclic aromatic hydrocarbons. , 1991, Carcinogenesis.

[7]  F. Guengerich,et al.  Comparison of levels of several human microsomal cytochrome P-450 enzymes and epoxide hydrolase in normal and disease states using immunochemical analysis of surgical liver samples. , 1991, The Journal of pharmacology and experimental therapeutics.

[8]  F. Guengerich,et al.  Role of human cytochrome P-450 IIE1 in the oxidation of many low molecular weight cancer suspects. , 1991, Chemical research in toxicology.

[9]  M. Romkes,et al.  Cloning and expression of complementary DNAs for multiple members of the human cytochrome P450IIC subfamily. , 1991, Biochemistry.

[10]  M. Sari,et al.  Catalytic activities of human liver cytochrome P-450 IIIA4 expressed in Saccharomyces cerevisiae. , 1990, Biochemistry.

[11]  M. Boyd,et al.  Expression of CYP1A1 gene in patients with lung cancer: evidence for cigarette smoke-induced gene expression in normal lung tissue and for altered gene regulation in primary pulmonary carcinomas. , 1990, Journal of the National Cancer Institute.

[12]  F. Guengerich.  Mechanism-based inactivation of human liver microsomal cytochrome P-450 IIIA4 by gestodene. , 1990, Chemical research in toxicology.

[13]  P. Beaune,et al.  Expression of cytochrome P-450 enzymes in cultured human hepatocytes. , 1990, European journal of biochemistry.

[14]  R. Tukey,et al.  Metabolism of 2-acetylaminofluorene and benzo(a)pyrene and activation of food-derived heterocyclic amine mutagens by human cytochromes P-450. , 1990, Cancer research.

[15]  M. Soma,et al.  Fetus-specific expression of a form of cytochrome P-450 in human livers. , 1990, Biochemistry.

[16]  M. Relling,et al.  Tolbutamide and mephenytoin hydroxylation by human cytochrome P450s in the CYP2C subfamily. , 1990, The Journal of pharmacology and experimental therapeutics.

[17]  L. Marnett,et al.  Roles of individual human cytochrome P-450 enzymes in the bioactivation of benzo(a)pyrene, 7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene, and other dihydrodiol derivatives of polycyclic aromatic hydrocarbons. , 1989, Cancer research.

[18]  M. Butler,et al.  Human cytochrome P-450PA (P-450IA2), the phenacetin O-deethylase, is primarily responsible for the hepatic 3-demethylation of caffeine and N-oxidation of carcinogenic arylamines. , 1989, Proceedings of the National Academy of Sciences of the United States of America.

[19]  C. Wolf,et al.  Relative contribution of various forms of cytochrome P450 to the metabolism of benzo[a]pyrene by human liver microsomes. , 1989, Carcinogenesis.

[20]  T. Shimada,et al.  Human liver microsomal cytochrome P-450 enzymes involved in the bioactivation of procarcinogens detected by umu gene response in Salmonella typhimurium TA 1535/pSK1002. , 1989, Cancer research.

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

[22]  Y. Nogi,et al.  Expression of a human P-450IIC gene in yeast cells using galactose-inducible expression system. , 1989, Molecular pharmacology.

[23]  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.

[24]  T. Shimada,et al.  Evidence for cytochrome P-450NF, the nifedipine oxidase, being the principal enzyme involved in the bioactivation of aflatoxins in human liver. , 1989, Proceedings of the National Academy of Sciences of the United States of America.

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

[26]  L. Benson,et al.  Foreign compound metabolism studies with human liver obtained as surgical waste. Relation to donor characteristics and effects of tissue storage. , 1988, Drug metabolism and disposition: the biological fate of chemicals.

[27]  F. Guengerich.  Oxidation of 17 alpha-ethynylestradiol by human liver cytochrome P-450. , 1988, Molecular pharmacology.

[28]  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.

[29]  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.

[30]  T. Shimada,et al.  SOS-inducing activity of chemical carcinogens and mutagens in Salmonella typhimurium TA1535/pSK1002: examination with 151 chemicals. , 1987, Mutation research.

[31]  S. Wrighton,et al.  Purification and characterization of ethanol-inducible human hepatic cytochrome P-450HLj. , 1987, Archives of biochemistry and biophysics.

[32]  F. Guengerich,et al.  Cloning and sequence determination of a complementary DNA related to human liver microsomal cytochrome P-450 S-mephenytoin 4-hydroxylase. , 1987, Biochemistry.

[33]  T. Kamataki,et al.  Significance of cytochrome P-450 (P-450 HFLa) of human fetal livers in the steroid and drug oxidations. , 1987, Biochemical pharmacology.

[34]  D. Waxman,et al.  Characterization of rat and human liver microsomal cytochrome P-450 forms involved in nifedipine oxidation, a prototype for genetic polymorphism in oxidative drug metabolism. , 1986, The Journal of biological chemistry.

[35]  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.

[36]  H. Shinagawa,et al.  Evaluation of the new system (umu-test) for the detection of environmental mutagens and carcinogens. , 1985, Mutation research.

[37]  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.

[38]  W. Kalow,et al.  In vitro inhibition studies of two isozymes of human liver cytochrome P-450. Mephenytoin p-hydroxylase and sparteine monooxygenase. , 1985, Drug metabolism and disposition: the biological fate of chemicals.

[39]  F. Guengerich,et al.  Purification and characterization of the rat liver microsomal cytochrome P-450 involved in the 4-hydroxylation of debrisoquine, a prototype for genetic variation in oxidative drug metabolism. , 1984, Biochemistry.

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

[41]  D. Pessayre,et al.  Inactivation of cytochrome P-450 by a troleandomycin metabolite. Protective role of glutathione. , 1983, The Journal of pharmacology and experimental therapeutics.

[42]  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.

[43]  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.

[44]  F. Guengerich,et al.  [16] Production and application of antibodies to rat liver cytochrome P-450 , 1981 .

[45]  F. Guengerich,et al.  Production and application of antibodies to rat liver cytochrome P-450. , 1981, Methods in enzymology.

[46]  A. Conney,et al.  Activation and inhibition of benzo(a)pyrene and aflatoxin B1 metabolism in human liver microsomes by naturally occurring flavonoids. , 1981, Cancer research.

[47]  F. Guengerich,et al.  Aryl hydrocarbon hydroxylase is inhibited by antibody to rat liver cytochrome P-450. , 1980, Science.

[48]  M. Brodie,et al.  Monooxygenase activity of human liver in microsomal fractions of needle biopsy specimens. , 1980, British journal of clinical pharmacology.

[49]  L. Powell,et al.  Drug metabolism in liver disease: Activity of hepatic microsomal metabolizing enzymes , 1979, Clinical pharmacology and therapeutics.

[50]  B. Masters,et al.  Characteristics of benzo(a)pyrene metabolism by kidney, liver and lung microsomal fractions from rodents and humans. , 1979, Cancer research.

[51]  P. Thomas,et al.  Separation and characterization of highly purified forms of liver microsomal cytochrome P-450 from rats treated with polychlorinated biphenyls, phenobarbital, and 3-methylcholanthrene. , 1979, The Journal of biological chemistry.

[52]  D. Jerina,et al.  Tumorigenicity studies with diol-epoxides of benzo(a)pyrene which indicate that (+/-)-trans-7beta,8alpha-dihydroxy-9alpha,10alpha-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene is an ultimate carcinogen in newborn mice. , 1978, Cancer research.

[53]  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.

[54]  G. Kellermann,et al.  Genetic variation of aryl hydrocarbon hydroxylase in human lymphocytes. , 1973, American journal of human genetics.

[55]  D. Nebert,et al.  Substrate-inducible microsomal aryl hydroxylase in mammalian cell culture. I. Assay and properties of induced enzyme. , 1968, The Journal of biological chemistry.

[56]  T. Omura,et al.  THE CARBON MONOXIDE-BINDING PIGMENT OF LIVER MICROSOMES. I. EVIDENCE FOR ITS HEMOPROTEIN NATURE. , 1964, The Journal of biological chemistry.

[57]  P. D. Lawley,et al.  Evidence for the Binding of Polynuclear Aromatic Hydrocarbons to the Nucleic Acids of Mouse Skin : Relation between Carcinogenic Power of Hydrocarbons and their Binding to Deoxyribonucleic Acid , 1964, Nature.

[58]  E. Miller.  Studies on the formation of protein-bound derivatives of 3,4-benzpyrene in the epidermal fraction of mouse skin. , 1951, Cancer research.

[59]  J. W. Cook,et al.  106. The isolation of a cancer-producing hydrocarbon from coal tar. Parts I, II, and III , 1933 .