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Glutathione S-Transferase Pi 1 (GSTP1) Gene 313 A/G (rs1695) polymorphism is associated with the risk of urinary bladder cancer: Evidence from a systematic review and meta-analysis based on 34 case-control studies. Gene 2019; 719:144077. [DOI: 10.1016/j.gene.2019.144077] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 08/20/2019] [Accepted: 08/22/2019] [Indexed: 12/24/2022]
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Zhou T, Li HY, Xie WJ, Zhong Z, Zhong H, Lin ZJ. Association of Glutathione S-transferase gene polymorphism with bladder Cancer susceptibility. BMC Cancer 2018; 18:1088. [PMID: 30419877 PMCID: PMC6233535 DOI: 10.1186/s12885-018-5014-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 10/30/2018] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND We conducted a meta-analysis to evaluate the relationship between the glutathione S-transferase μ1 (GSTM1)- and glutathione S-transferase θ1 (GSTT1)- null genotypes and susceptibility to bladder cancer. METHODS We identified association reports from the databases of PubMed, Embase, the Cochrane Library and the China Biological Medicine Database (CBM disc) on July 1, 2017 and synthesized eligible investigations. Results were expressed using odds ratios (ORs) for dichotomous data, and we also calculated 95% confidence intervals (CIs). RESULTS In this meta-analysis, we found that the GSTM1-null genotype was associated with bladder cancer risk in the overall population, and individually in whites, Africans and Asians (overall population: OR = 1.40, 95% CI: 1.31-1.48, P<0.00001; whites: OR = 1.39, 95% CI: 1.26-1.54, P<0.00001; Africans: OR = 1.54, 95% CI: 1.16-2.05, P = 0.003; Asians: OR = 1.45, 95% CI: 1.33-1.59, P<0.00001). The GSTT1-null genotype was associated with bladder cancer risk in the overall population, but not in whites, in Africans or Asians (overall population: OR = 1.11, 95% CI: 1.01-1.22, P = 0.03; whites: OR = 1.16, 95% CI: 0.99-1.36, P = 0.07; Africans: OR = 1.07, 95% CI: 0.65-1.76, P = 0.79; Asians: OR = 1.05, 95% CI: 0.91-1.22, P = 0.51). Interestingly, a dual-null GSTM1-GSTT1 genotype was associated with bladder cancer risk in the overall population and in Asians (overall population: OR = 1.48, 95% CI: 1.15-1.92, P = 0.002; Asians: OR = 1.62, 95% CI: 1.15-2.28, P = 0.006). In conclusion, the GSTM1-null, GSTT1-null and dual-null GSTM1-GSTT1 genotypes might be associated with the onset of bladder cancer, but additional genetic-epidemiological studies should be conducted to explore this association further.
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Affiliation(s)
- Tianbiao Zhou
- Department of Nephrology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, 515041 China
| | - Hong-Yan Li
- Department of Nephrology, Huadu District People’s Hospital of Guangzhou, Southern Medical University, Guangzhou, China
| | - Wei-Ji Xie
- Department of Nephrology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, 515041 China
| | - Zhiqing Zhong
- Department of Nephrology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, 515041 China
| | - Hongzhen Zhong
- Department of Nephrology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, 515041 China
| | - Zhi-Jun Lin
- Department of Nephrology, The Second Affiliated Hospital of Shantou University Medical College, Shantou, 515041 China
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Craft S, Ekena J, Mayer B, Thamm DH, Saba C, Chun R, Trepanier LA. Characterization of a low expression haplotype in canine glutathione S-transferase (GSTT1) and its prevalence in golden retrievers. Vet Comp Oncol 2017; 16:E61-E67. [PMID: 28840668 DOI: 10.1111/vco.12333] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 06/05/2017] [Accepted: 06/11/2017] [Indexed: 12/12/2022]
Abstract
Glutathione S-transferase-theta (GSTT1) is a carcinogen detoxification enzyme, and low activity variants are associated with lymphoma in humans. We recently found a variant in the 3' untranslated region (UTR) of canine GSTT1, *101_102insT, which was predicted to change miRNA binding and was found in 5 of 17 golden retriever (GR) dogs with lymphoma but none of 14 healthy GRs. The aim of this study was to determine whether this variant led to decreased GSTT1 expression and was a discernible risk factor for lymphoma within the GR breed. On resequencing, *101_102insT appeared to be in complete linkage disequilibrium with 3 additional 3'UTR variants, leading to the inferred haplotype *3T>C; *101_102insT; *190C>A; *203T>C. In canine livers that were heterozygous for this variant haplotype, GSTT1 protein expression was significantly lower compared to the reference haplotype (densitometry .40 vs .64, P = .022), and GSTT1 transcript levels by qPCR were also significantly lower (fold difference .52, P = .012), without evidence of substantial allelic expression imbalance. The variant haplotype led to >50% decrease in expression in vitro (.31 ± .07 vs .64 ± .19; P = .019). We found no significant difference in minor allele frequencies between 71 GR dogs with lymphoma (MAF .162) and 33 healthy age-matched controls (MAF .136, P = .69). Our results indicate that the variant GSTT1 3'UTR haplotype containing *101_102insT reduces gene expression, which could lead to impaired carcinogen detoxification, but was not a detectable risk factor for lymphoma in GR dogs.
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Affiliation(s)
- S Craft
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - J Ekena
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - B Mayer
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - D H Thamm
- Flint Animal Cancer Center, Colorado State University, Fort Collins, Colorado
| | - C Saba
- Department of Small Animal Medicine and Surgery, University of Georgia, Athens, Georgia
| | - R Chun
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - L A Trepanier
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
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Yu Y, Li X, Liang C, Tang J, Qin Z, Wang C, Xu W, Hua Y, Shao P, Xu T. The relationship between GSTA1, GSTM1, GSTP1, and GSTT1 genetic polymorphisms and bladder cancer susceptibility: A meta-analysis. Medicine (Baltimore) 2016; 95:e4900. [PMID: 27631264 PMCID: PMC5402607 DOI: 10.1097/md.0000000000004900] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Previous studies have investigated the relationship between GSTA1, GSTM1, GSTP1, and GSTT1 polymorphisms and bladder cancer (BCa) susceptibility, respectively, but the results remain inconsistent. So, we conducted this meta-analysis including 79 case-control studies to explore such relationships. METHODS We searched PubMed, EMBASE, Cochrane library, Web of Science, and CNKI for relevant available studies. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were implemented to evaluate the intensity of associations. Publication bias was estimated using Begg funnel plots and Egger regression test. To assess the stability of the results, we used sensitivity analysis with the method of calculating the results again by omitting 1 single study each time. Between-study heterogeneity was tested using the I statistic. RESULTS No significant association between GSTA1 polymorphism and BCa susceptibility (OR = 1.05, 95% CI 0.83-1.33) was noted. Besides, meaningful association between individuals who carried the GSTM1 null genotype and increased BCa risk was detected (OR = 1.39, 95%CI 1.28-1.51). When stratified by ethnicity, significant difference was found in both Caucasian (OR = 1.39, 95% CI 1.23-1.58) and Asian populations (OR = 1.45, 95% CI 1.31-1.61). Moreover, in the subgroup analysis by source of controls (SOC), the results were significant in both hospital-based control groups (OR = 1.49, 95% CI 1.35-1.64) and population-based control groups (OR = 1.21, 95% CI = 1.07-1.37). Additionally, the analysis revealed no significant association between GSTP1 polymorphism and BCa risk (OR = 1.07, 95% CI 0.96-1.20). What is more, significant associations between GSTT1 polymorphism and BCa susceptibility were discovered (OR = 1.11, 95% CI 1.00-1.22). In the subgroup analysis by ethnicity, significant associations between GSTT1 null genotype and BCa risk were observed only in Caucasians (OR = 1.25, 95% CI 1.09-1.44). Furthermore, when stratified by SOC, no obvious relationship was found between the GSTT1 null genotype polymorphism with hospital-based population (OR = 1.11, 95% CI 0.97-1.28) or population-based population (OR = 1.10, 95% CI 0.96-1.27). CONCLUSION This study suggested that GSTM1 null genotype and GSTT1 null genotype might be related to higher BCa risk, respectively. However, no associations were observed between GSTA1 or GSTP1 polymorphisms and BCa susceptibility.
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Affiliation(s)
- Yajie Yu
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
| | - Xiao Li
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
- Department of Urologic Surgery, The Affiliated Cancer Hospital of Jiangsu Province of Nanjing Medical University, Nanjing, China
| | - Chao Liang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
| | - Jingyuan Tang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
| | - Zhiqiang Qin
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
| | - Chengming Wang
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
| | - Weizhang Xu
- Department of Thoracic Surgery, Nanjing Medical University Affiliated Cancer Hospital; Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Cancer Institute of Jiangsu Province
| | - Yibo Hua
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
| | - Pengfei Shao
- Department of Urology, The First Affiliated Hospital of Nanjing Medical University
- Correspondence: Pengfei Shao, Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China (e-mail: ); Ting Xu, Department of Urologic Surgery, The Affiliated Cancer Hospital of Jiangsu Province of Nanjing Medical University, Nanjing 210009, China (e-mail: )
| | - Ting Xu
- Department of Urologic Surgery, The Affiliated Cancer Hospital of Jiangsu Province of Nanjing Medical University, Nanjing, China
- Correspondence: Pengfei Shao, Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China (e-mail: ); Ting Xu, Department of Urologic Surgery, The Affiliated Cancer Hospital of Jiangsu Province of Nanjing Medical University, Nanjing 210009, China (e-mail: )
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Gong M, Dong W, An R. Glutathione S-transferase T1 Polymorphism Contributes to Bladder Cancer Risk: A Meta-Analysis Involving 50 Studies. DNA Cell Biol 2012; 31:1187-97. [PMID: 22339266 DOI: 10.1089/dna.2011.1567] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Mancheng Gong
- Department of Urological Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Wenjing Dong
- Department of Oncology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Ruihua An
- Department of Urological Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
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Genetic polymorphisms of glutathione S-transferase M1 and bladder cancer risk: a meta-analysis of 26 studies. Mol Biol Rep 2010; 38:2491-7. [DOI: 10.1007/s11033-010-0386-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2010] [Accepted: 11/08/2010] [Indexed: 01/13/2023]
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Zeng FF, Liu SY, Wei W, Yao SP, Zhu S, Li KS, Wan G, Zhang HT, Zhong M, Wang BY. Genetic polymorphisms of glutathione S-transferase T1 and bladder cancer risk: a meta-analysis. Clin Exp Med 2009; 10:59-68. [DOI: 10.1007/s10238-009-0070-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Accepted: 09/09/2009] [Indexed: 01/28/2023]
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Abd El Hameed AH, Negm OE, El-Gamal OM, Hamouda HE, El Nouby KA, Ismail GM. Genetic polymorphism of glutathione S-transferases M1 and T1 in Egyptian patients with bilharzial bladder cancer. Urol Oncol 2008; 28:296-301. [PMID: 19117770 DOI: 10.1016/j.urolonc.2008.09.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 09/03/2008] [Accepted: 09/05/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To assess the influence of glutathione S-transferases M1 and T1 (GSTM1 and T1) genotype on the risk of bladder cancer in patients with urinary bilharziasis. MATERIALS AND METHODS This study was designed as a case-control study that involved 60 individuals who were enrolled into 3 equal groups. The first one included patients with bilharzial bladder cancer, the second one had those with nonmalignant urinary bilharziasis, and the last one was the control group. All of the participants were adult males, nonsmokers, and with matched ages. All of them underwent an assessment of the serum level of the total GST concentration and the polymerase chain reaction (PCR) was used for determination of the GSTM1 and T1 genotypes. RESULTS The lower most GST enzyme concentration was reported in patients with bilharzial bladder cancer (26 +/- 4.4 ng/ml) with significant difference between it and that of the second group (36.8 +/- 4.1 ng/ml, P < 0.05) and that of the controls (40.4 +/- 4 ng/ml, P < 0.005). The PCR results have demonstrated that the frequency of combined GSTM1 and T1 genes deletion (M1-ve T1-ve) was significantly higher in cases of bladder cancer (40%) than those of the controls (5%, P < 0.005) and those of the second group (10%, P < 0.05). The unconditional logistic regression test revealed that patients with urinary bilharziasis and combined GSTM1 and T1 genes deletion are at a significant risk for malignant transformation (OR = 6.3, P < 0.05). CONCLUSIONS Patients with urinary bilharziasis and GSTM1-ve and T1-ve genes might be at increased risk of bladder cancer. However, larger studies are needed for confirmation of these results.
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Association between polymorphisms in the biometabolism genes CYP1A1, GSTM1, GSTT1 and GSTP1 in bladder cancer. Clin Exp Med 2008; 9:21-8. [DOI: 10.1007/s10238-008-0015-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Accepted: 09/15/2008] [Indexed: 10/21/2022]
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Sirugo G, Hennig BJ, Adeyemo AA, Matimba A, Newport MJ, Ibrahim ME, Ryckman KK, Tacconelli A, Mariani-Costantini R, Novelli G, Soodyall H, Rotimi CN, Ramesar RS, Tishkoff SA, Williams SM. Genetic studies of African populations: an overview on disease susceptibility and response to vaccines and therapeutics. Hum Genet 2008; 123:557-98. [PMID: 18512079 DOI: 10.1007/s00439-008-0511-y] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Accepted: 05/07/2008] [Indexed: 01/13/2023]
Abstract
Africa is the ultimate source of modern humans and as such harbors more genetic variation than any other continent. For this reason, studies of the patterns of genetic variation in African populations are crucial to understanding how genes affect phenotypic variation, including disease predisposition. In addition, the patterns of extant genetic variation in Africa are important for understanding how genetic variation affects infectious diseases that are a major problem in Africa, such as malaria, tuberculosis, schistosomiasis, and HIV/AIDS. Therefore, elucidating the role that genetic susceptibility to infectious diseases plays is critical to improving the health of people in Africa. It is also of note that recent and ongoing social and cultural changes in sub-Saharan Africa have increased the prevalence of non-communicable diseases that will also require genetic analyses to improve disease prevention and treatment. In this review we give special attention to many of the past and ongoing studies, emphasizing those in Sub-Saharan Africans that address the role of genetic variation in human disease.
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Affiliation(s)
- Giorgio Sirugo
- Medical Research Council Laboratories, Fajara, The Gambia, West Africa.
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Sanyal S, Ryk C, De Verdier PJ, Steineck G, Larsson P, Onelöv E, Hemminki K, Kumar R. Polymorphisms in NQO1 and the clinical course of urinary bladder neoplasms. ACTA ACUST UNITED AC 2007; 41:182-90. [PMID: 17469025 DOI: 10.1080/00365590600991946] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
OBJECTIVE Urinary bladder neoplasms differ considerably in biological potential, and tumor morphology alone cannot predict their clinical behaviors. Polymorphisms in xenobiotic metabolic genes reportedly modulate susceptibility to bladder neoplasms and may affect the clinical course and outcomes of the disease. This study was conducted to determine the effect of polymorphisms in the xenobiotic metabolic genes on the disease course and clinical outcomes of urinary bladder neoplasms. MATERIAL AND METHODS Patients with urinary bladder neoplasms who had been followed up for a 5-year period were genotyped for NQO1 (R139W, P187S), NAT (rapid/slow), GSTP1 (I105V), GSTT1 and GSTM1 (non-null/null) and MTHFR (A222V, E429A) polymorphisms. RESULTS Variant allele carriers of the NQO1 (P187S) polymorphism showed a higher risk for high-stage disease than non-carriers at diagnosis [relative risk (RR)=1.4; 95% CI 1.0-1.8). A higher risk for highly malignant disease (T2+) was also observed in variant allele carriers than non-carriers of the GSTP1 (I105V) polymorphism (RR=1.6; 95% CI 1.1-2.5). NQO1 (R139W) variant allele carrier patients with intermediate malignant disease (TaG3+T1) had shorter disease-free survival than non-carriers (p=0.05). In contrast, carriers of the variant allele for the MTHFR (A222V) polymorphism had significantly longer disease-free survival than non-carriers (p=0.02). CONCLUSIONS Our data are consistent with the notion that NQO1 polymorphisms influence the course and clinical outcomes of urinary bladder neoplasms. However, our results need to be confirmed in a large study as most of the associations detected were only of marginal statistical significance, and would be lost on correction for multiple comparisons.
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Affiliation(s)
- Somali Sanyal
- Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm, Sweden
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Cengiz M, Ozaydin A, Ozkilic AC, Dedekarginoglu G. The investigation of GSTT1, GSTM1 and SOD polymorphism in bladder cancer patients. Int Urol Nephrol 2007; 39:1043-8. [PMID: 17340208 DOI: 10.1007/s11255-007-9179-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Accepted: 01/12/2007] [Indexed: 10/23/2022]
Abstract
Glutathione S transferases (GSTT1, GSTM1, GSTP1) are enzymes that activate the detoxification of endogenous and exogenous agents. The genetic polymorphism in these genes may change the response of individuals to environmental toxicants. The genetic polymorphisms of GSTT1, GSTM1, GSTP1 have been studied extensively in the determination of individual cancer risks. Some studies showed a strong relationship between polymorphism of GSTs and superoxidedismutase enzymes. Using the polymerase chain reaction (PCR) the prevalence of genetic polymorphisms of GSTT1, GSTM1 and MnSOD (Manganese Superoxide Dismurase) was investigated in 104 cases and controls to seek any association with the risk of bladder cancer. The frequency of GSTT1 +/+ polymorphism was 65% (33/51) in the cases and 79% (42/53) in the controls. The frequency of the GSTM1 +/+ polymorphism was 33% (17/51) in the cases and 58% (31/53) in the controls. The frequency of the GSTM1 null genotype was 42% (22/53) in the controls and 68% (34/51) in the patients. The frequency of the SOD AA genotype was 36% (17/51) in the cases and 33% (19/53) in the controls. There was no association between the GSTT1 and SOD polymorphism and bladder cancer incidence. The incidence of the GSTM1 null genotype was increased in bladder cancer patients compared to controls (OR = 1.755, 95% CI = 1.119-2.751).
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Affiliation(s)
- Müjgan Cengiz
- Department Of Medical Biology, Cerrahpaşa Medical Faculty, Istanbul University, Istanbul, Turkey
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Saad AA, O'Connor PJ, Mostafa MH, Metwalli NE, Cooper DP, Margison GP, Povey AC. Bladder Tumor Contains Higher N7-Methylguanine Levels in DNA than Adjacent Normal Bladder Epithelium. Cancer Epidemiol Biomarkers Prev 2006; 15:740-3. [PMID: 16614117 DOI: 10.1158/1055-9965.epi-05-0813] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Schistosoma haematobium-infected patients are more likely to develop bladder cancer and be more exposed to carcinogenic N-nitroso compounds than uninfected patients. As N7-methylguanine is a marker of exposure to methylating agents of this type, we have measured N7-methyldeoxyguanosine 3'-monophosphate (N7-MedGp) by (32)P postlabeling. DNA was isolated from 42 paired normal and tumor tissue of Egyptians with bladder cancer. N7-MedGp was detected in DNA from 93% of the tumors and 74% of the normal bladder tissue samples. Adduct levels were highly variable and ranged from 0.04 to 6.4 and from 0.02 to 0.72 micromol/mol deoxyguanosine 3'-monophosphate (dGp) in tumor and normal DNA, respectively. N7-MedGp levels in normal and tumor DNA were highly correlated with one another (P = 0.007). The mean difference (95% confidence interval) in adduct levels between tumor and normal DNA was 0.21 (0.13-0.32) micromol/mol dGp and this was statistically significant (P < 0.001). The adduct ratio (tumor DNA/normal DNA) varied between 0.2 and 136 (median, 4.6). N7-MedGp levels were not associated with gender, age, or the presence of schistosomiasis. However, lower N7-MedGp levels were found in normal DNA from individuals lacking the GSTM1 gene (P = 0.03) but not the GSTT1 gene or in subjects with the Ile105Val GSTP1 polymorphism. These results show that exposure to methylating agents is widespread and suggest that such exposure may play a role both in tumor initiation and progression.
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Affiliation(s)
- Abir A Saad
- Cancer Research UK Carcinogenesis Group, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Manchester
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