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Zhu Z, Zhang J, Jiang W, Zhang X, Li Y, Xu X. Risks on N-acetyltransferase 2 and bladder cancer: a meta-analysis. Onco Targets Ther 2015; 8:3715-20. [PMID: 26715854 PMCID: PMC4685932 DOI: 10.2147/ott.s82927] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background It is known that bladder cancer disease is closely related to aromatic amine compounds, which could cause cancer by regulating of N-acetylation and N-acetyltransferase 1 and 2 (NAT1 and NAT2). The NAT2 slowed acetylation and would increase the risk of bladder cancer, with tobacco smoke being regarded as a risk factor for this increased risk. However, the relationship between NAT2 slow acetylation and bladder cancer is still debatable at present. This study aims to explore preliminarily correlation of NAT2 slow acetylation and the risk of bladder cancer. Methods The articles were searched from PubMed, Cochran, McGrane English databases, CBM, CNKI, and other databases. The extraction of bladder cancer patients and a control group related with the NAT2 gene were detected by the state, and the referenced articles and publications were also used for data retrieval. Using a random effects model, the model assumes that the studies included in the analysis cases belong to the overall population in the study of random sampling, and considering the variables within and between studies. Data were analyzed using STATA Version 6.0 software, using the META module. According to the inclusion and exclusion criteria of the literature study, 20 independent studies are included in this meta-analysis. Results The results showed that the individual differences of bladder cancer susceptibility might be part of the metabolism of carcinogens. Slow acetylation status of bladder cancer associated with the pooled odds ratio was 1.31 (95% confidence interval: 1.11–1.55). Conclusion The status of NAT2 slow N-acetylation is associated with bladder cancer risks, and may increase the risk of bladder cancer.
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Affiliation(s)
- Zongheng Zhu
- Department of General Surgery, Huangshi Love & Health Hospital, Huangshi, People's Republic of China
| | - Jinshan Zhang
- Department of Tumor surgery, Huangshi Central Hospital, Huangshi, People's Republic of China
| | - Wei Jiang
- Department of Urinary Surgery, Huangshi No 5 Hospital, Huangshi, People's Republic of China
| | - Xianjue Zhang
- Department of Urinary Surgery Jingzhou Central Hospital, Jingzhou, People's Republic of China
| | - Youkong Li
- Department of Urinary Surgery Jingzhou Central Hospital, Jingzhou, People's Republic of China
| | - Xiaoming Xu
- Department of Bone Surgery, Jingzhou Central Hospital, Jingzhou, People's Republic of China
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D'errico A, Taioli E, Chen X, Vineis P. Genetic metabolic polymorphisms and the risk of cancer: a review of the literature. Biomarkers 2008; 1:149-73. [DOI: 10.3109/13547509609079352] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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3
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Hein DW. N-acetyltransferase 2 genetic polymorphism: effects of carcinogen and haplotype on urinary bladder cancer risk. Oncogene 2006; 25:1649-58. [PMID: 16550165 PMCID: PMC1434721 DOI: 10.1038/sj.onc.1209374] [Citation(s) in RCA: 145] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A role for the N-acetyltransferase 2 (NAT2) genetic polymorphism in cancer risk has been the subject of numerous studies. Although comprehensive reviews of the NAT2 acetylation polymorphism have been published elsewhere, the objective of this paper is to briefly highlight some important features of the NAT2 acetylation polymorphism that are not universally accepted to better understand the role of NAT2 polymorphism in carcinogenic risk assessment. NAT2 slow acetylator phenotype(s) infer a consistent and robust increase in urinary bladder cancer risk following exposures to aromatic amine carcinogens. However, identification of specific carcinogens is important as the effect of NAT2 polymorphism on urinary bladder cancer differs dramatically between monoarylamines and diarylamines. Misclassifications of carcinogen exposure and NAT2 genotype/phenotype confound evidence for a real biological effect. Functional understanding of the effects of NAT2 genetic polymorphisms on metabolism and genotoxicity, tissue-specific expression and the elucidation of the molecular mechanisms responsible are critical for the interpretation of previous and future human molecular epidemiology investigations into the role of NAT2 polymorphism on cancer risk. Although associations have been reported for various cancers, this paper focuses on urinary bladder cancer, a cancer in which a role for NAT2 polymorphism was first proposed and for which evidence is accumulating that the effect is biologically significant with important public health implications.
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Affiliation(s)
- D W Hein
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, USA.
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4
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Salanti G, Higgins JPT, White IR. Bayesian synthesis of epidemiological evidence with different combinations of exposure groups: application to a gene–gene–environment interaction. Stat Med 2006; 25:4147-63. [PMID: 16955540 DOI: 10.1002/sim.2689] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Meta-analysis to investigate the joint effect of multiple factors in the aetiology of a disease is of increasing importance in epidemiology. This task is often challenging in practice, because studies typically concentrate on studying the effect of only one exposure, sometimes may report the interaction between two exposures, but rarely address more complex interactions that involve more than two exposures. In this paper, we develop a meta-analysis framework that combines estimates from studies of multiple exposures. A key development is an approach to combining results from studies that report information on any subset or combination of the full set of exposures. The model requires assumptions to be made about the prevalence of the specific exposures. We discuss several possible model specifications and prior distributions, including information internal and external to the meta-analysis data set, and using fixed-effect and random-effects meta-analysis assumptions. The methodology is implemented in an original meta-analysis of studies relating the risk of bladder cancer to two N-acetyltransferase genes, NAT1 and NAT2, and smoking status.
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5
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Green J, Banks E, Berrington A, Darby S, Deo H, Newton R. N-acetyltransferase 2 and bladder cancer: an overview and consideration of the evidence for gene-environment interaction. Br J Cancer 2000; 83:412-7. [PMID: 10917561 PMCID: PMC2374558 DOI: 10.1054/bjoc.2000.1265] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Genetic polymorphism of the carcinogen metabolizing enzyme N-acetyl transferase 2 (NAT2) may influence susceptibility to bladder cancers related to smoking or to occupational exposure to arylamine carcinogens. This article reviews the results of 21 published case-control studies of NAT2 polymorphism and bladder-cancer risk, with a total of 2700 cases and 3426 controls. The published evidence suggests that NAT2 slow acetylator phenotype or genotype may be associated with a small increase in bladder cancer risk. However, given the possibility of selective publication of results from studies that found an excess risk, the current evidence is not sufficient to conclude that there is a real increase in risk. Only five of the 21 studies reported results separately for the effect of NAT2 on bladder cancer risk in smokers and non-smokers. Although the results suggest that the effect may be greater in smokers than in non-smokers, the possibility of publication bias makes these results difficult to interpret. There was insufficient evidence to assess the joint effect of NAT2 and occupational exposure to arylamines on bladder cancer risk. Even if estimates of the effect of NAT2 from published data are correct, studies with around 3000-5000 cases will be needed to confirm them.
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Affiliation(s)
- J Green
- Imperial Cancer Research Fund Cancer Epidemiology Unit, University of Oxford, Radcliffe Infirmary, UK
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6
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Schnakenberg E, Lustig M, Breuer R, Werdin R, Hübotter R, Dreikorn K, Schloot W. Gender-specific effects of NAT2 and GSTM1 in bladder cancer. Clin Genet 2000; 57:270-7. [PMID: 10845567 DOI: 10.1034/j.1399-0004.2000.570405.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
One approach for risk assessment of cancer is the evaluation of polymorphic enzymes involved in cancer using molecular tools. Phase II enzymes are involved in the detoxification of several drugs, environmental substances and carcinogenic compounds. Here, we analyzed enzymes for their putative relevance in urinary bladder cancer. The hereditable enzyme polymorphism of arylamine N-acetyltransferase 2 (NAT2) and glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) was studied in 157 hospital-based patients and in 223 control subjects. Slow acetylation was not observed to be a significant risk factor of developing bladder cancer (OR: 1.33; 95% CI 0.85-2.09). One genotype responsible for slow acetylation (NAT2*5B/*6A) was observed significantly more frequently in bladder cancer patients compared with control subjects (OR: 1.63; 95% CI 1.03-2.58). Gender-specific effects were observed when patients were divided into subgroups. In male patients, slow acetylators were identified as carrying a significant increased risk of developing bladder cancer, in particular when the genotype NAT2*5B/*6A was combined with the GSTM1 null genotype (OR: 4.39; 95% CI 1.98-9.74). By contrast, the same genotype combination significantly protected female patients from bladder cancer (OR: 0.21; 95% CI 0.06-0.80).
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Affiliation(s)
- E Schnakenberg
- Center for Human Genetics and Genetic Counselling, University of Bremen, Germany
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7
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Marcus PM, Vineis P, Rothman N. NAT2 slow acetylation and bladder cancer risk: a meta-analysis of 22 case-control studies conducted in the general population. PHARMACOGENETICS 2000; 10:115-22. [PMID: 10761999 DOI: 10.1097/00008571-200003000-00003] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The NAT2 gene is involved in phase II detoxification of aromatic monoamines, a class of known bladder carcinogens. Certain allelic combinations result in the slow acetylation phenotype, which is thought to increase bladder cancer risk. We conducted a meta-analysis of all identifiable published case-control studies conducted in the general population that had examined the relationship of acetylation status and bladder cancer risk (22 studies, 2496 cases, 3340 controls). Using meta-analysis techniques that employed weighting based on individual-study variation, slow acetylators had an approximately 40% increase in risk compared with rapid acetylators [odds ratio (OR) 1.4, 95% confidence interval (CI) 1.2-1.6]. Statistical tests indicated, however, that pooling of all studies, or of studies conducted in Caucasian populations, hid potentially important heterogeneity in the individual study results, and suggested that the relationship of NAT2 slow acetylation and bladder cancer risk might differ by geographical region. Studies conducted in Asia generated a summary OR of 2.1 (CI 1.2-3.8), in Europe, a summary OR of 1.4 (CI 1.2-1.6), and in the USA, a summary OR of 0.9 (CI 0.7-1.3). Among European studies, the relationship between NAT2 slow acetylation and bladder cancer risk did not differ by method used to assess acetylation status (older drug-based phenotyping methods: 10 studies, OR 1.5, CI 1.2-1.8; more recent NAT2 genotyping methods: four studies, OR 1.4, CI 1.1-1.7). Our results suggest that in most populations studied to date, NAT2 slow acetylation status is associated with a modest increase in bladder cancer risk.
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Affiliation(s)
- P M Marcus
- Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland 20892-7354, USA.
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8
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Johns LE, Houlston RS. N-acetyl transferase-2 and bladder cancer risk: a meta-analysis. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2000; 36:221-227. [PMID: 11044903 DOI: 10.1002/1098-2280(2000)36:3<221::aid-em5>3.0.co;2-q] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Interindividual differences in bladder cancer susceptibility may be partly mediated through polymorphic variability in the metabolism of carcinogens. N-acetyl transferase-2 (NAT2) has been extensively studied as a risk factor in this context, but the results are inconsistent. In some studies the failure to demonstrate a relationship may be a consequence of a lack of statistical power. To overcome lack of power, data from 21 published case-control studies were pooled in a meta-analysis using a random-effects model. The pooled odds ratio of bladder cancer associated with slow acetylator status was 1.31 (95% CI: 1.11-1.55). The results suggest that NAT2 slow acetylator status is associated with a modest increase in risk of bladder cancer. There was, however, heterogeneity between studies. It is clear from this overview that greater attention should be paid to the design of these types of study.
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Affiliation(s)
- L E Johns
- Section of Cancer Genetics, Institute of Cancer Research, Sutton, Surrey, United Kingdom
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9
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Hengstler JG, Arand M, Herrero ME, Oesch F. Polymorphisms of N-acetyltransferases, glutathione S-transferases, microsomal epoxide hydrolase and sulfotransferases: influence on cancer susceptibility. Recent Results Cancer Res 1999; 154:47-85. [PMID: 10026993 DOI: 10.1007/978-3-642-46870-4_4] [Citation(s) in RCA: 163] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
It has become clear that several polymorphisms of human drug-metabolizing enzymes influence an individual's susceptibility for chemical carcinogenesis. This review gives an overview on relevant polymorphisms of four families of drug-metabolizing enzymes. Rapid acetylators (with respect to N-acetyltransferase NAT2) were shown to have an increased risk of colon cancer, but a decreased risk of bladder cancer. In addition an association between a NAT1 variant allele (NAT*10, due to mutations in the polyadenylation site causing approximately two fold higher activity) and colorectal cancer among NAT2 rapid acetylators was observed, suggesting a possible interaction between NAT1 and NAT2. Glutathione S-transferases M1 and T1 (GSTM1 and GSTT1) are polymorphic due to large deletions in the structural gene. Meta-analysis of 12 case-control studies demonstrated a significant association between the homozygous deletion of GSTM1 (GSTM1-0) and lung cancer (odds ratio: 1.41; 95% CI: 1.23-1.61). Combination of GSTM1-0 with two allelic variants of cytochrome P4501A1 (CYP1A1), CYP1A1 m2/m2 and CYP1A1 Val/Val further increases the risk for lung cancer. Indirect mechanisms by which deletion of GSTM1 increases risk for lung cancer may include GSTM1-0 associated decreased expression of GST M3 and increased activity of CYP1A1 and 1A2. Combination of GST M1-0 and NAT2 slow acetylation was associated with markedly increased risk for lung cancer (odds ratio: 7.8; 95% CI: 1.4-78.7). In addition GSTM1-0 is clearly associated with bladder cancer and possibly also with colorectal, hepatocellular, gastric, esophageal (interaction with CYP1A1), head and neck as well as cutaneous cancer. In individuals with the GSTT1-0 genotype more chromosomal aberrations and sister chromatid exchanges (SCEs) were observed after exposure to 1,3-butadiene or various haloalkanes or haloalkenes. Evidence for an association between GSTT1-0 and myelodysplastic syndrome and acute lymphoblastic leukemia has been presented. A polymorphic site of GSTP1 (valine to isoleucine at codon 104) decreases activity to several carcinogenic diol epoxides and was associated with testicular, bladder and lung cancer. Microsomal expoxide hydrolase (mEH) is polymorphic due to amino acid variation at residues 113 and 139. Polymorphic variants of mEH were associated with hepatocellular cancer (His-113 allele), ovarian cancer (Tyr-113 allele) and chronic obstructive pulmonary disease (His-113 allele). Three human sulfotransferases (STs) are regulated by genetic polymorphisms (hDHEAST, hM-PST, TS PST). Since a large number of environmental mutagens are activated by STs an association with human cancer risk might be expected.
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10
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Brockmöller J, Cascorbi I, Kerb R, Sachse C, Roots I. Polymorphisms in xenobiotic conjugation and disease predisposition. Toxicol Lett 1998; 102-103:173-83. [PMID: 10022251 DOI: 10.1016/s0378-4274(98)00304-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Low activity of arylamine N-acetyltransferase 2 (slow NAT2) was consistently associated with urinary bladder cancer risk. The increased cancer risk attributable to slow NAT2 was more significant when taking gene-environment interactions and gene-gene interactions into account. In urinary bladder, slow NAT2 was no risk factor in subjects who never smoked but became increasingly relevant with increasing lifetime dose of tobacco smoke expressed by an odds ratio of 2.7 for slow NAT2 in extensive smokers. The functional impact of some arylamine N-acetyltransferase 1 variants is controversial. It was published that the NAT1 allele 10 was associated with high enzyme activity and that there was an overrepresentation of carriers of NAT1*10 in bladder and colon cancer, but we could only detect a moderately elevated activity of NAT1*10 and an underrepresentation of fast NAT1 alleles in bladder cancer. Recently, a C/A-polymorphism in intron 1 of cytochrome P450 1A2 was associated with high inducibility and persons with this high inducibility variant were overrepresented in bladder cancer, but only if they were smokers or if they had slow NAT2 genotypes. Numerous studies have shown that glutathione S-transferase M1 deficiency (GSTM1*0/0) increases the risk for lung and bladder cancer but the overall risk attributable to GSTM1*0/0 was only around 1.3 according to meta-analyses. The GSTM1*0/0 genotype appears to be the best established metabolic susceptibility factor. Several independent experimental approaches showed that GSTM1 decreases mutagenicity of reactive epoxides and it was shown that carriers of GSTM1*0/0 were at increased risk for several types of cancer and other diseases. There are also studies which showed no effects of GSTM1, a result which is compatible with the assumption that GSTM1*0/0 is a susceptibility factor of moderate strength. GSTM1*0/0 may, however, become a dominant risk factor in certain gene-gene combinations such as the combination with highly active CYP1A1 gene variants or in combination with specific types of exposure. Specific precautions have to be taken in the design of molecular epidemiological studies on risk factors with moderate strength; some requirements for high quality molecular epidemiological studies will be discussed in this article. Molecular epidemiology is an increasingly powerful approach to understand carcinogenesis and may be used in the future to individualize cancer prevention strategies.
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Affiliation(s)
- J Brockmöller
- Institute of Clinical Pharmacology, University Clinic Charité, Humboldt University of Berlin, Germany.
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11
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Proceedings of the British Toxicology Society Annual Congress University of Surrey, Guildford 19 - 22 April 1998. Hum Exp Toxicol 1998. [DOI: 10.1177/096032719801700901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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12
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Puga A, Nebert DW, McKinnon RA, Menon AG. Genetic polymorphisms in human drug-metabolizing enzymes: potential uses of reverse genetics to identify genes of toxicological relevance. Crit Rev Toxicol 1997; 27:199-222. [PMID: 9099519 DOI: 10.3109/10408449709021619] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The human mind was engaged with fundamental questions on the nature of heredity long before the study of genetics became a scientific discipline. Many traits, such as height, eye color, blood pressure, or cancer susceptibility, have been known to run in families, although the genes or combination of genes that underlie these observable characteristics remain unknown in most cases. Differences in susceptibility to environmental agents in humans are likewise determined by variations in genetic background--genetic polymorphisms. In this article, we review the current status of studies on human polymorphisms in drug-metabolizing enzymes and discuss various approaches to the analysis of genetic polymorphisms. We expect that in the near future, novel methods in genetic analysis of human populations will be likely to play a key role in the identification of genes of toxicological relevance.
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Affiliation(s)
- A Puga
- Center for Environmental Genetics, University of Cincinnati Medical Center, Ohio 45267-0056, USA
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13
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Nebert DW, McKinnon RA, Puga A. Human drug-metabolizing enzyme polymorphisms: effects on risk of toxicity and cancer. DNA Cell Biol 1996; 15:273-80. [PMID: 8639263 DOI: 10.1089/dna.1996.15.273] [Citation(s) in RCA: 189] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A growing number of human genetic polymorphisms in drug-metabolizing enzymes (DMEs) are being characterized. Some of these have been shown, quite convincingly, to be correlated with risk of toxicity or cancer, whereas others presently remain equivocal. There is good evidence that the correlation is stronger in populations exposed to a variety of environmental procarcinogens; perhaps 30% of DME substrates are able to be metabolically potentiated. Phase I DMEs, most of which represent cytochromes P450, metabolically activate procarcinogens to genotoxic electrophilic intermediates, and Phase II DMEs conjugate the intermediates to water-soluble derivatives, completing the detoxification cycle. It follows that genetic differences in the regulation, expression and activity of genes coding for Phase I and Phase II DMEs would be crucial factors in defining cancer susceptibility and the toxic or carcinogenic power of environmental chemicals. Not all Phase I and Phase II DMEs are implicated in detoxification; previous work from this and from other laboratories has identified candidate Phase I and Phase II genes in which certain alleles are more likely to be associated with cancer susceptibility. In some cases, the allelic frequencies vary dramatically between ethnic groups. In this review, our current knowledge about polymorphisms in the following genes are updated: the aromatic hydrocarbon receptor (AHR), the CYP1A1 structural gene (which encodes aryl hydrocarbon hydroxylase activity), the CYP1A2 structural gene (arylamine oxidations), the CYP2C19 gene (S-mephenytoin 4'-hydroxylase), the CYP2D6 gene (debrisoquine hydroxylase), the CYP2E1 gene (N,N-dimethylnitrosamine N-demethylase), the null mutant for the GSTM1 gene (glutathione transferase mu), and the NAT2 gene (arylamine N-acetyltransferase). If unequivocal biomarkers of genetic susceptibility to cancer and toxicity can be developed successfully, then identification of individuals at increased risk would be very helpful in the fields of public health and preventive medicine.
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Affiliation(s)
- D W Nebert
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati Medical Center, Ohio 45267-0057, USA
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Affiliation(s)
- F P Perera
- Columbia University School of Public Health, New York, NY 10032
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Perera F. Biomarkers and molecular epidemiology of occupationally related cancer. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1993; 40:203-15. [PMID: 8230296 DOI: 10.1080/15287399309531788] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Effective prevention of cancer requires sensitive early warning systems to identify groups, and ultimately individuals, who are at high risk of developing cancer and to accurately estimate the magnitude of their risk. Incorporated with molecular epidemiologic studies, biologic markers have the potential to provide quantitative human data on the biologically effective dose of carcinogens, resultant molecular effects, and genetic/acquired factors that modulate these effects. Clearly, this information is directly relevant to risk identification and to risk quantification.
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Affiliation(s)
- F Perera
- Division of Environmental Sciences, Columbia University, School of Public Health, New York, NY 10032
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Abstract
Polymorphisms have been detected in a variety of xenobiotic-metabolizing enzymes at both the phenotypic and genotypic level. In the case of four enzymes, the cytochrome P450 CYP2D6, glutathione S-transferase mu, N-acetyltransferase 2 and serum cholinesterase, the majority of mutations which give rise to a defective phenotype have now been identified. Another group of enzymes show definite polymorphism at the phenotypic level but the exact genetic mechanisms responsible are not yet clear. These enzymes include the cytochromes P450 CYP1A1, CYP1A2 and a CYP2C form which metabolizes mephenytoin, a flavin-linked monooxygenase (fish-odour syndrome), paraoxonase, UDP-glucuronosyltransferase (Gilbert's syndrome) and thiopurine S-methyltransferase. In the case of a further group of enzymes, there is some evidence for polymorphism at either the phenotypic or genotypic level but this has not been unambiguously demonstrated. Examples of this class include the cytochrome P450 enzymes CYP2A6, CYP2E1, CYP2C9 and CYP3A4, xanthine oxidase, an S-oxidase which metabolizes carbocysteine, epoxide hydrolase, two forms of sulphotransferase and several methyltransferases. The nature of all these polymorphisms and possible polymorphisms is discussed in detail, with particular reference to the effects of this variation on drug metabolism and susceptibility to chemically-induced diseases.
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Affiliation(s)
- A K Daly
- Department of Pharmacological Sciences, University of Newcastle upon Tyne, Medical School, U.K
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Abstract
Numerous environmental and host factors, some of which are known and some unknown, contribute to cancer development. While data and studies abound, our current understanding of the relation between cancer and the environment is still very limited. Understanding environmental carcinogenesis is critical to its effective management. Biotechnology has revolutionalized the study of biological and biomedical sciences. This minireview provides an overview of environmental carcinogenesis with emphasis on the contributions and prospects of biotechnology in advancing an understanding of environmental carcinogenesis for its prevention and intervention.
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Affiliation(s)
- M M Chu
- Office of Research and Development, US EPA, Washington, DC 20460
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Affiliation(s)
- D A Evans
- Riyadh Armed Forces Hospital, Saudi Arabia
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Sardaş S, Karakaya AE, Idle JR. Are the traits for drug acetylation and oxidation co-inherited? Clin Genet 1988; 34:143-4. [PMID: 3191610 DOI: 10.1111/j.1399-0004.1988.tb02852.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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