title: Glutathione S-transferase polymorphism interactions with smoking status and HPV infection in cervical cancer risk: an evidence-based meta-analysis.
abstract: BACKGROUND
  Human papillomavirus (HPV) infection is considered the major cause of cervical cancer (CC), but a number of infected women do not develop invasive lesions, suggesting the role of genetic susceptibility and environmental co-factors for cancer outbreak. Glutathione S- transferases (GSTs) are multifunctional enzymes that play a key role in the detoxification of varieties of both endogenous products of oxidative stress and exogenous carcinogens.
  
  
  METHODS
  MEDLINE, EMBASE, and Cochrane databases were searched. All studies evaluating the association between GSTM1 polymorphisms and cervical cancer were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed-or random-effects model.
  
  
  RESULTS
  A total of 23 case-control studies were included in the meta-analysis. The overall result showed that the association between GSTM1 null genotype and risk for cervical cancer was statistically significant (OR = 1.56; 95%CI, 1.39-1.75). Subgroup analyses were performed based on ethnicity, smoking and HPV infection. Our results showed that smokers with null GSTM1 genotype had higher risk of cervical cancer (OR = 2.27, 95%CI, 1.46-3.54). For the ethnicity stratification, significant increased risk of null GSTM1 genotype was found in Chinese and Indian population, but no increased risk in other population was found.
  
  
  CONCLUSIONS
  this meta-analysis provided strong evidence that the GSTM1 genotype is associated with CC development, especially in Chinese and Indian populations. Smoking and HPV infection modified the association between the null GSTM1 genotype and CC.
authors.affiliation: Xijing Hospital, Fourth Military Medical University, Xi'an, China ; Department of Gynecology, The 307 Hospital of the Academy of Military Medical Sciences, Beijing, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Zhen
authors.affiliation: Department of Gynecology, The 307 Hospital of the Academy of Military Medical Sciences, Beijing, China.
authors.forename: Chen-Ming
authors.initials: CM
authors.lastname: Hu
authors.affiliation: Department of Gynecology, The 307 Hospital of the Academy of Military Medical Sciences, Beijing, China.
authors.forename: Li-Hong
authors.initials: LH
authors.lastname: Bian
mesh_terms: D016022:Case-Control Studies; D005006:Ethnicity / Q000235:genetics; D019317:Evidence-Based Medicine; D005260:Female; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D030361:Papillomavirus Infections / Q000150:complications*; D011110:Polymorphism, Genetic; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D002583:Uterine Cervical Neoplasms / Q000201:enzymology / Q000209:etiology* / Q000235:genetics
chemical_list: D005982:Glutathione Transferase