title: Systematic evaluation of cancer risk associated with DNMT3B polymorphisms.
abstract: OBJECTIVE
  The aim of our study is to provide a precise quantification for the association between DNA methyltransferase 3B (DNMT3B) variations (rs2424913 C/T, rs1569686 G/T, rs6087990 T/C and rs2424908 T/C) and the risk of cancer.
  
  
  METHODS
  We performed a systematic literature review and assessed the methodological quality of included case-control designed studies based on Newcastle-Ottawa Scale. Pooled odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs) were calculated to assess the strengths of the associations.
  
  
  RESULTS
  We identified 34 studies for pooled analyses. Overall, the results demonstrated that rs2424913 polymorphism was significantly associated with negative cancer risk in the African population (CT vs TT: OR 0.10, 95% CI 0.02-0.63, P = 0.01; CT+CC vs TT: OR 0.14, 95% CI 0.03-0.76, P = 0.02), and the rs1569686 polymorphism was significantly associated with a subtly decreased cancer risk (GT vs TT: OR 0.80, 95% CI 0.72-0.90, P < 0.01; GT+GG vs TT: OR 0.84, 95% CI 0.76-0.94, P < 0.01), particularly in the Asian population (GT vs TT: OR 0.79, 95% CI 0.66-0.96, P < 0.01) and in colorectal cancer subgroup (G vs T: OR 0.69, 95% CI 0.54-0.88, P < 0.01). In addition, the rs6087990 polymorphism was associated with decreased risk in Asian population (T vs C: OR 0.77, 95% CI 0.62-0.96, P = 0.02). Similarly, the rs2424908 polymorphism was observed as a protective factor for cancer in the Asian population (CT+CC vs TT: OR 0.79, 95% CI 0.66-0.95, P = 0.01).
  
  
  CONCLUSIONS
  DNMT3B polymorphisms might be associated with decreased cancer risk especially in the Asian population and for colorectal cancer. Further multicentric studies are still needed to confirm the results.
authors.affiliation: Department of Hospital Infection Management, Affiliated Tumor Hospital of Zhengzhou University, Zhengzhou, Henan, China, fjduan@yeah.net.
authors.forename: Fujiao
authors.initials: F
authors.lastname: Duan
authors.forename: Shuli
authors.initials: S
authors.lastname: Cui
authors.forename: Chunhua
authors.initials: C
authors.lastname: Song
authors.forename: Liping
authors.initials: L
authors.lastname: Dai
authors.forename: Xia
authors.initials: X
authors.lastname: Zhao
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Zhang
mesh_terms: D044466:Asian People / Q000235:genetics; D016022:Case-Control Studies; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics*; D005787:Gene Frequency; D056726:Genetic Association Studies; D018740:Genetic Heterogeneity; D020022:Genetic Predisposition to Disease; D006801:Humans; D009369:Neoplasms / Q000453:epidemiology / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D012306:Risk; D000097584:DNA Methyltransferase 3B
chemical_list: D004248:DNA (Cytosine-5-)-Methyltransferases; D000097584:DNA Methyltransferase 3B