title: Effects of common polymorphisms rs11614913 in miR-196a2 and rs2910164 in miR-146a on cancer susceptibility: a meta-analysis.
abstract: BACKGROUND
  MicroRNAs regulate gene expression at the post-transcriptional level and involved in diverse biological and pathological processes, including tumorigenesis. Rs11614913 in miR-196a2 and rs2910164 in miR-146a are shown to associate with increased/decreased cancer risk. We performed a meta-analysis to systematically summarize the possible association.
  
  
  RESULTS
  We assessed published studies of the association between these microRNA polymorphisms and cancer risk from eleven studies with 16,771 subjects for miR-196a2 and from ten studies with 15,126 subjects for miR-146a. As for rs11614913, the contrast of homozygote (TT vs CC: OR = 0.92, 95% CI = 0.85-0.99, P(heterogeneity) = 0.45), allele (T vs C: OR = 0.96, 95% CI = 0.92-0.99, P(heterogeneity) = 0.61) and recessive model (OR = 0.90, 95% CI = 0.84-0.97, P(heterogeneity) = 0.50) produced statistically association. Subgroup analysis by ethnicity, statistically significantly decreased cancer risks were found among Asians for allele contrast (OR = 0.95, 95% CI = 0.90-0.99, P(heterogeneity) = 0.74) and the recessive genetic model (OR = 0.90, 95% CI = 0.82-0.98, P(heterogeneity) = 0.85). According to subgroup analysis by tumor types, the protective effect of C/T polymorphism was only found in breast cancer under allele contrast (T vs C: OR = 0.94, 95% CI = 0.88-0.99, P(heterogeneity) = 0.26). For rs2910164, no significant associations were found among overall analysis model with relatively large heterogeneity. Through the stratified analysis, heterogeneity decreased significantly. In the subgroup analyses by cancer types, the C allele of rs2910164 was associated with protection from digestive cancer in allele contrast (C vs G: OR = 0.86, 95% CI = 0.77-0.96, P(heterogeneity) = 0.51).
  
  
  CONCLUSIONS
  Our meta-analysis suggests that the rs11614913 most likely contributes to decreased susceptibility to cancer, especially in Asians and breast cancer. Besides, the C allele of the rs2910164 might be associated with a protection from digestive cancer.
authors.affiliation: Department of Geriatrics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.forename: Jijun
authors.initials: J
authors.lastname: Xu
authors.forename: Shifeng
authors.initials: S
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Chen
authors.forename: Xueli
authors.initials: X
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Yun
authors.initials: Y
authors.lastname: Qian
authors.forename: Weihong
authors.initials: W
authors.lastname: Zhao
authors.forename: Jianqing
authors.initials: J
authors.lastname: Wu
mesh_terms: D000483:Alleles; D020022:Genetic Predisposition to Disease; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D009369:Neoplasms / Q000145:classification / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D017594:Publication Bias; D012307:Risk Factors
chemical_list: C542542:MIRN146 microRNA, human; C542543:MIRN196 microRNA, human; D035683:MicroRNAs