title: Prognostic role of common microRNA polymorphisms in cancers: evidence from a meta-analysis.
abstract: BACKGROUND
  The morbidity and mortality of cancer increase remarkably every year. It's a heavy burden for family and society. The detection of prognostic biomarkers can help to improve the theraputic effect and prolong the lifetime of patients. microRNAs have an influential role in cancer prognosis. The results of articles discussing the relationship between microRNA polymorphisms and cancer prognosis are inconsistent.
  
  
  METHODS
  We conduct a meta-analysis of 19 publications concerning the association of four common polymorphisms, mir-146a rs2910164, mir-149 rs2292832, mir-196a2 rs11614913 and mir-499 rs3746444, with cancer prognosis. Pooled Hazard Ratios with 95% Confidence Intervals for the relationship between four genetic polymorphisms and Overall Survival, Recurrence-free Survival, Disease-free survival, recurrence are calculated. Subgroup analysis by population and type of tumor are conducted.
  
  
  RESULTS
  GG genotype of mir-146a may be the protective factor for overall survival, especially in Caucasian population. C-containing genotypes of mir-196a2 act as a risk role for overall survival. The same result exists in Asian population, in Non-Small Cell Lung Cancer and digestive cancer. The patients with C allele of mir-149 have a better overall survival, especially in Non-Small Cell Lung Cancer. No significant results are obtained for mir-499 polymorphisms.
  
  
  CONCLUSIONS
  Genetic polymorphisms in mir-146a, mir-196a2 and mir-149 may be associated with overall survival. This effect varies with different types of cancer. Genetic polymorphism in mir-499 may have nothing to do with cancer prognosis.
authors.affiliation: Department of Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province, China; Key Laboratory of Cancer Etiology and Intervention, University of Liaoning Province, Shenyang, China.
authors.forename: Lingzi
authors.initials: L
authors.lastname: Xia
authors.affiliation: Department of Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province, China; Key Laboratory of Cancer Etiology and Intervention, University of Liaoning Province, Shenyang, China.
authors.forename: Yangwu
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Department of Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province, China; Key Laboratory of Cancer Etiology and Intervention, University of Liaoning Province, Shenyang, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Fang
authors.affiliation: Department of Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province, China; Key Laboratory of Cancer Etiology and Intervention, University of Liaoning Province, Shenyang, China.
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Yin
authors.affiliation: Department of Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province, China; Key Laboratory of Cancer Etiology and Intervention, University of Liaoning Province, Shenyang, China.
authors.forename: Xuelian
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province, China; Key Laboratory of Cancer Etiology and Intervention, University of Liaoning Province, Shenyang, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.affiliation: Department of Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province, China; Key Laboratory of Cancer Etiology and Intervention, University of Liaoning Province, Shenyang, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Guan
authors.affiliation: Department of Epidemiology, School of Public Health, China Medical University, Shenyang, Liaoning Province, China; Key Laboratory of Cancer Etiology and Intervention, University of Liaoning Province, Shenyang, China.
authors.forename: Baosen
authors.initials: B
authors.lastname: Zhou
mesh_terms: D000483:Alleles; D018572:Disease-Free Survival; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D009364:Neoplasm Recurrence, Local / Q000235:genetics* / Q000473:pathology; D009369:Neoplasms / Q000235:genetics* / Q000473:pathology; D020641:Polymorphism, Single Nucleotide; D011379:Prognosis; D012307:Risk Factors
chemical_list: D035683:MicroRNAs