title: Functional polymorphisms in the interleukin-12 gene contribute to cancer risk: evidence from a meta-analysis of 18 case-control studies.
abstract: BACKGROUND
  Emerging evidence from preclinical and clinical studies has shown that interleukin-12 (IL-12) has some effectiveness against endogenously arising carcinogenesis. Several potentially functional polymorphisms of IL-12 gene have been implicated in cancer risk, but individually published studies showed inconclusive results. The aim of this study was to investigate the association between IL-12 polymorphisms and cancer risk.
  
  
  METHODS
  The MEDLINE, EMBASE, Web of science and CBM databases were searched for all articles published up to June 10, 2012 that addressed IL-12 polymorphisms and cancer risk. Statistical analyses were performed using RevMan 5.1.6 and STATA 12.0 softwares.
  
  
  RESULTS
  Eighteen studies were included with a total of 6463 cancer cases and 7412 healthy controls. We found that the 3'UTR A>C (rs3212227) polymorphism of IL-12B gene was associated with significantly increased overall risk of cancers using random effects model (C vs A: odds ratio [OR]=1.14, 95% confidence interval [CI]: 1.02-1.27; AC+CC vs AA: OR=1.20, 95%CI: 1.01-1.43). However, the 3'UTR G>A (rs568408), IVS2 T>A (rs582054) and 5'UTR T>G (rs2243115) polymorphisms of IL-12A gene did not appear to have an influence on cancer susceptibility. Further subgroup analyses showed that the 3'UTR A>C (rs3212227) polymorphism was associated with increased cancer risks in the subgroups of Asians, cervical and nasopharyngeal cancers.
  
  
  CONCLUSIONS
  Results from the current meta-analysis indicates that the 3'UTR A>C (rs3212227) polymorphism of IL-12B gene might be a potential biomarker for cancer risk among Asians, especially for cervical and nasopharyngeal cancers.
authors.affiliation: The Department of Laboratory Medicine, The First Affiliated Hospital of China Medical University, Shenyang 110001, PR China. zhouliping750825@hotmail.com
authors.forename: Liping
authors.initials: L
authors.lastname: Zhou
authors.forename: Fan
authors.initials: F
authors.lastname: Yao
authors.forename: Hong
authors.initials: H
authors.lastname: Luan
authors.forename: Yinling
authors.initials: Y
authors.lastname: Wang
authors.forename: Xihua
authors.initials: X
authors.lastname: Dong
authors.forename: Wenwen
authors.initials: W
authors.lastname: Zhou
authors.forename: Qihui
authors.initials: Q
authors.lastname: Wang
mesh_terms: D000483:Alleles; D044466:Asian People / Q000235:genetics; D044383:Black People / Q000235:genetics; D016022:Case-Control Studies; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000208:ethnology / Q000235:genetics*; D005838:Genotype; D006801:Humans; D018664:Interleukin-12 / Q000235:genetics*; D053765:Interleukin-12 Subunit p35 / Q000235:genetics; D053762:Interleukin-12 Subunit p40 / Q000235:genetics; D009369:Neoplasms / Q000208:ethnology / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D018570:Risk Assessment / Q000379:methods / Q000706:statistics & numerical data; D012307:Risk Factors; D044465:White People / Q000235:genetics
chemical_list: D053765:Interleukin-12 Subunit p35; D053762:Interleukin-12 Subunit p40; D018664:Interleukin-12