title: Association of the glutathione s-transferase m1, t1 polymorphisms with cancer: evidence from a meta-analysis.
abstract: BACKGROUND
  Glutathione S-transferases (GSTs) are a family of multifunctional enzymes that are involved in the metabolism of many xenobiotics, including a wide range of environmental carcinogens. While the null genotypes in GSTM1 and GSTT1 have been implicated in tumorigenesis, it remains inconsistent and inconclusive. Herein, we aimed to assess the possible associations of the GSTM1 and GSTT1 null genotype in cancer risks.
  
  
  METHODS
  A meta-analysis based on 506 case-control studies was performed. Odds ratios (OR) with corresponding 95% confidence intervals (CIs) were used to assess the association.
  
  
  RESULTS
  The null genotypes of GSTM1 and GSTT1 polymorphisms were associated with a significantly increased risk in cancer (for GSTM1: OR = 1.17; 95%CI = 1.14-1.21; for GSTT1: OR = 1.16; 95%CI = 1.11-1.21, respectively). When the analysis was performed based on their smoking history, the risk associated of GSTM1 null and GSTT1 null genotypes with cancer is further increased (for GSTM1: OR = 2.66; 95%CI = 2.19-3.24; for GSTT1: OR = 2.46; 95%CI = 1.83-3.32, respectively).
  
  
  CONCLUSIONS
  These findings indicate that GSTM1 and GSTT1 polymorphisms may play critical roles in the development of cancer, especially in smokers.
authors.affiliation: State Key Laboratory of Reproductive Medicine, Department of Urology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Jianzheng
authors.initials: J
authors.lastname: Fang
authors.forename: Shangqian
authors.initials: S
authors.lastname: Wang
authors.forename: Shengli
authors.initials: S
authors.lastname: Zhang
authors.forename: Shifeng
authors.initials: S
authors.lastname: Su
authors.forename: Zhen
authors.initials: Z
authors.lastname: Song
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Deng
authors.forename: Hongqing
authors.initials: H
authors.lastname: Cui
authors.forename: Hainan
authors.initials: H
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jian
authors.initials: J
authors.lastname: Qian
authors.forename: Jinbao
authors.initials: J
authors.lastname: Gu
authors.forename: Bianjiang
authors.initials: B
authors.lastname: Liu
authors.forename: Pengchao
authors.initials: P
authors.lastname: Li
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.forename: Xinnong
authors.initials: X
authors.lastname: Liu
authors.forename: Zengjun
authors.initials: Z
authors.lastname: Wang
mesh_terms: D016022:Case-Control Studies; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D009369:Neoplasms / Q000235:genetics* / Q000473:pathology; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects
chemical_list: D005982:Glutathione Transferase; C413545:glutathione S-transferase T1