title: Association between the HSPA1B ±1267A/G polymorphism and cancer risk: a meta-analysis of 14 case-control studies.
abstract: BACKGROUND
  Previous epidemiological studies have suggested a potential role of the HSPA1B±1267A/G polymorphism in risk of developing cancer. However, the results were inconsistent. Therefore, we performed this meta-analysis to summarize the possible association with cancer risk.
  
  
  METHODS
  We retrieved relevant articles from PubMed, EMBASE, ISI Web of Science, Chinese Biomedical Literature and Chinese National Knowledge Infrastructure. Studies were selected using specific criteria. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess those associations. All analyses were performed using STATA software.
  
  
  RESULTS
  Fourteen case-control studies, including 1, 834 cancer cases and 2, 028 controls were included in this meta-analysis. Overall, the results indicated that the G allele of HSPA1B gene ±1267A/G was significantly associated with an increased cancer risk in all genetic models (G vs A: OR=1.51, 95%CI 1.17-1.95, p=0.001; GG vs AA: OR=2.93, 95%CI 1.50-5.74, p=0.002; AG vs AA: OR=1.48, 95%CI 1.10-1.98, p=0.009; GG/AG vs AA: OR=1.69, 95%CI 1.22-2.33, p=0.001; GG vs
  OR=2.31, 95%CI 1.24-4.32, p=0.009). In the subgroup analysis stratified by ethnicity, a significant association was identified in Caucasians (G vs A: OR=1.35, 95%CI 1.08-1.69, p=0.008; GG/AG vs AA: OR=1.36, 95%CI 1.09-1.70, p=0.007), but not in Asians. In the stratified analysis by cancer types, individuals with the G allele showed an increased risk of hepatocellular carcinoma compared with carriers of the A allele (OR=2.40, 95%CI 1.47-3.91, p< 0.001). Inversely, individuals with the GG genotype showed a decreased risk of gastric cancer compared with carriers of the AG/GG genotypes (GG vs
  OR=0.39, 95%CI 0.20-0.70, p=0.007).
  
  
  CONCLUSIONS
  This meta-analysis suggests associations between the HSPA1B ±1267A/G polymorphism and risk of cancer. However, this association might be Caucasian-specific and the G allele of this polymorphism probably increases risk of hepatocellular carcinoma while decreasing risk of gastric cancer. Further well-designed studies based on larger sample sizes are needed to validate these findings.
authors.affiliation: Chengdu Municipal Center for Disease Control and Prevention, Chengdu, China E-mail : kuangdan007@sina.com.
authors.forename: Dan
authors.initials: D
authors.lastname: Kuang
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Yue-Zhang
authors.initials: YZ
authors.lastname: Song
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Yu
authors.forename: Dong-Ying
authors.initials: DY
authors.lastname: Zhang
authors.forename: Lang
authors.initials: L
authors.lastname: Wu
authors.forename: Jie
authors.initials: J
authors.lastname: Tang
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000453:epidemiology / Q000235:genetics*; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D006801:Humans; D008113:Liver Neoplasms / Q000453:epidemiology / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D012306:Risk; D013274:Stomach Neoplasms / Q000453:epidemiology / Q000235:genetics*; D044465:White People
chemical_list: D018840:HSP70 Heat-Shock Proteins; C525621:HSPA1B protein, human