This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Fang, J.-L. Articles by Lazarus, P. Search for Related Content PubMed PubMed Citation Articles by Fang, J.-L. Articles by Lazarus, P.

Characterization of Benzo(a)pyrene-trans-7,8-dihydrodiol Glucuronidation by Human Tissue Microsomes and Overexpressed UDP-glucuronosyltransferase Enzymes¹

Divisions of Cancer Control and Molecular Oncology, H. Lee Moffitt Cancer Center, Interdisciplinary Oncology Program and Departments of Biochemistry and Pharmacology and Therapeutics, University of South Florida, Tampa, Florida 33612 [J-L. F., D. W., P. L.]; Division of Biochemical Toxicology, National Center for Toxicological Research, Jefferson, Arkansas 72079 [F. A. B., D. R. D.]; Oncology and Molecular Endocrinology Research Center, CHUL Research Center (CHUQ), School of Pharmacy, Laval University, Quebec, Canada G1V-4G2 [C. G.]; and Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, 1049-001 Lisboa, Portugal [M. M. M.]

UDP-glucuronosyltransferase (UGT)-mediated glucuronidation of benzo(a)pyrene-trans-7,8-dihydrodiol (BPD), precursor to the potent mutagen benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide, may be an important pathway in the detoxification of benzo(a)pyrene. To better characterize this pathway in humans, high-pressure liquid chromatography (HPLC) was used to detect glucuronide conjugates of BPD formed in vitro. Three peaks were detected by HPLC after incubation of racemic BPD with human liver microsomes; these were identified as monoglucuronides by liquid chromatography-mass spectrometry analysis. Proton nuclear magnetic resonance spectroscopy of isolated fractions, combined with HPLC analysis of the glucuronide products from human liver microsomal incubations with purified benzo(a)pyrene-trans-7S,8S-dihydrodiol [(+)-BPD] and benzo(a)pyrene-trans-7R,8R-dihydrodiol [(-)-BPD] forms of BPD, indicated that peak 1 contained the 7-glucuronide of 7S,8S-BPD (BPD-7S-Gluc), peak 2 was a mixture of the 7-glucuronide of 7R,8R-BPD (BPD-7R-Gluc) and the 8-glucuronide of 7S,8S-BPD (BPD-8S-Gluc), and peak 3 contained the 8-glucuronide of 7R, 8R-BPD (BPD-8R-Gluc). In liver microsomes, peak 1 (BPD-7S-Gluc) was the largest peak observed, whereas in microsomes from aerodigestive tract tissues, peak 2 (both BPD-7R-Gluc and BPD-8S-Gluc) was the largest HPLC peak observed. The liver enzymes UGT1A1 and UGT2B7 formed BPD-7S-Gluc as the major diastereomer, whereas UGT1A8 and UGT1A10, extrahepatic enzymes present in the aerodigestive tract, preferentially formed both BPD-7R-Gluc and BPD-8S-Gluc. In addition, both UGT1A9 and UGT1A7 preferentially formed BPD-7R-Gluc. No detectable glucuronidating activity against BPD was observed by UGT1A3, UGT1A4, UGT1A6, UGT2B4, UGT2B15, or UGT2B17. The affinity of individual UGT enzymes as determined by K_m analysis was UGT1A10 > UGT1A9 > UGT1A1 > UGT1A7 for (-)-BPD and UGT1A10 > UGT1A9 > UGT2B7 UGT1A1 > UGT1A7 for (+)-BPD. These results suggest that several UGTs may play an important role in the overall glucuronidation of BPD in humans, with UGT1A1, UGT1A7, UGT1A9, UGT1A10 and potentially UGT1A8 playing an important role in the glucuronidation of the procarcinogenic (-)-BPD enantiomer, and that the stereospecific activity exhibited by different UGTs against BPD is consistent with tissue-specific patterns of BPD glucuronide diastereomer formation and UGT expression.

This article has been cited by other articles:

				K. C. Olson, R. W. Dellinger, Q. Zhong, D. Sun, S. Amin, T. E. Spratt, and P. Lazarus Functional Characterization of Low-Prevalence Missense Polymorphisms in the UDP-Glucuronosyltransferase 1A9 Gene Drug Metab. Dispos., October 1, 2009; 37(10): 1999 - 2007. [Abstract] [Full Text] [PDF]

				R. M. Balliet, G. Chen, C. J. Gallagher, R. W. Dellinger, D. Sun, and P. Lazarus Characterization of UGTs Active against SAHA and Association between SAHA Glucuronidation Activity Phenotype with UGT Genotype Cancer Res., April 1, 2009; 69(7): 2981 - 2989. [Abstract] [Full Text] [PDF]

				D. Sun, A. K. Sharma, R. W. Dellinger, A. S. Blevins-Primeau, R. M. Balliet, G. Chen, T. Boyiri, S. Amin, and P. Lazarus Glucuronidation of Active Tamoxifen Metabolites by the Human UDP Glucuronosyltransferases Drug Metab. Dispos., November 1, 2007; 35(11): 2006 - 2014. [Abstract] [Full Text] [PDF]

				R. W. Dellinger, G. Chen, A. S. Blevins-Primeau, J. Krzeminski, S. Amin, and P. Lazarus Glucuronidation of PhIP and N-OH-PhIP by UDP-glucuronosyltransferase 1A10 Carcinogenesis, November 1, 2007; 28(11): 2412 - 2418. [Abstract] [Full Text] [PDF]

				C. J. Gallagher, J. E. Muscat, A. N. Hicks, Y. Zheng, A.-M. Dyer, G. A. Chase, J. Richie, and P. Lazarus The UDP-Glucuronosyltransferase 2B17 Gene Deletion Polymorphism: Sex-Specific Association with Urinary 4-(Methylnitrosamino)-1-(3-Pyridyl)-1-Butanol Glucuronidation Phenotype and Risk for Lung Cancer Cancer Epidemiol. Biomarkers Prev., April 1, 2007; 16(4): 823 - 828. [Abstract] [Full Text] [PDF]

				R. W. Dellinger, J.-L. Fang, G. Chen, R. Weinberg, and P. Lazarus IMPORTANCE OF UDP-GLUCURONOSYLTRANSFERASE 1A10 (UGT1A10) IN THE DETOXIFICATION OF POLYCYCLIC AROMATIC HYDROCARBONS: DECREASED GLUCURONIDATIVE ACTIVITY OF THE UGT1A10139LYS ISOFORM Drug Metab. Dispos., June 1, 2006; 34(6): 943 - 949. [Abstract] [Full Text] [PDF]

				L. M. Butler, Y. Duguay, R. C. Millikan, R. Sinha, J.-F. Gagne, R. S. Sandler, and C. Guillemette Joint Effects between UDP-Glucuronosyltransferase 1A7 Genotype and Dietary Carcinogen Exposure on Risk of Colon Cancer Cancer Epidemiol. Biomarkers Prev., July 1, 2005; 14(7): 1626 - 1632. [Abstract] [Full Text] [PDF]

				S. S. De Buck, F. B. Bouche, A. Brandenburger, and C. P. Muller Modulation of the metabolism and adverse effects of benzo[a]pyrene by a specific antibody: a novel host factor in environmental carcinogenesis? Carcinogenesis, April 1, 2005; 26(4): 835 - 844. [Abstract] [Full Text] [PDF]

				T. Almahmeed, J. O. Boyle, E. G. Cohen, J. F. Carew, B. Du, N. K. Altorki, L. Kopelovich, J.-L. Fang, P. Lazarus, K. Subbaramaiah, et al. Benzo[a]pyrene phenols are more potent inducers of CYP1A1, CYP1B1 and COX-2 than benzo[a]pyrene glucuronides in cell lines derived from the human aerodigestive tract Carcinogenesis, May 1, 2004; 25(5): 793 - 799. [Full Text] [PDF]

				Y. Wang, N. Kato, Y. Hoshida, M. Otsuka, H. Taniguchi, M. Moriyama, S. Shiina, T. Kawabe, Y. M. Ito, and M. Omata UDP-Glucuronosyltransferase 1A7 Genetic Polymorphisms Are Associated with Hepatocellular Carcinoma in Japanese Patients with Hepatitis C Virus Infection Clin. Cancer Res., April 1, 2004; 10(7): 2441 - 2446. [Abstract] [Full Text] [PDF]

				P. G. Wells, P. I. Mackenzie, J. Roy Chowdhury, C. Guillemette, P. A. Gregory, Y. Ishii, A. J. Hansen, F. K. Kessler, P. M. Kim, N. Roy Chowdhury, et al. GLUCURONIDATION AND THE UDP-GLUCURONOSYLTRANSFERASES IN HEALTH AND DISEASE Drug Metab. Dispos., March 1, 2004; 32(3): 281 - 290. [Abstract] [Full Text] [PDF]

				D. Wiener, D. R. Doerge, J.-L. Fang, P. Upadhyaya, and P. Lazarus CHARACTERIZATION OF N-GLUCURONIDATION OF THE LUNG CARCINOGEN 4-(METHYLNITROSAMINO)-1-(3-PYRIDYL)-1-BUTANOL (NNAL) IN HUMAN LIVER: IMPORTANCE OF UDP-GLUCURONOSYLTRANSFERASE 1A4 Drug Metab. Dispos., January 1, 2004; 32(1): 72 - 79. [Abstract] [Full Text] [PDF]

				J.-L. Fang and P. Lazarus Correlation between the UDP-Glucuronosyltransferase (UGT1A1) TATAA Box Polymorphism and Carcinogen Detoxification Phenotype: Significantly Decreased Glucuronidating Activity against Benzo(a)pyrene-7,8-dihydrodiol(-) in Liver Microsomes from Subjects with the UGT1A1*28 Variant Cancer Epidemiol. Biomarkers Prev., January 1, 2004; 13(1): 102 - 109. [Abstract] [Full Text] [PDF]