title: Interleukin-12B+1188A/C polymorphism contributes to increased hepatocellular carcinoma susceptibility: evidence from a meta-analysis.
abstract: BACKGROUND
  Interleukin-12 (IL-12) is a multifunctional cytokine that induces interferon (IFN)-γ secretion and plays an important role in antitumor immunity. The IL-12B +1188A/C polymorphism was found to correlate with a decreased cytokine production and/or activity, which may lead to increased susceptibility to cancers including hepatocellular carcinoma (HCC). Previous epidemiological studies investigating the association between IL-12B +1188A/C polymorphism and HCC risk reported inconsistent results. We performed a meta-analysis to derive a precise estimation of the association.
  
  
  METHODS
  All studies published up to July 2014 on the association between IL-12B +1188A/C polymorphism and HCC risk were identified by searching electronic databases including PubMed, Embase, Cochrane library, and Chinese Biomedical Literature database (CBM). Data were extracted by two independent authors and the odds ratios (ORs) together with corresponding 95% confidence intervals (CIs) were used to assess the association between IL-12B +1188A/C polymorphism and HCC risk.
  
  
  RESULTS
  Five studies with 1864 cases and 2077 controls were included in the meta-analysis. We observed that the IL-12B +1188A/C polymorphism was signiﬁcantly correlated with increased HCC risk when all studies were pooled into the meta-analysis (CC vs. AA: OR=1.306, 95% CI 1.063-1.606, P=0.011; AC vs. AA: OR=1.193, 95% CI 1.014-1.405, P=0.034; CC+AC vs. AA: OR=1.260, 95% CI 1.098-1.445, P=0.001). In subgroup analyses by ethnicity, source of control, and study quality, signiﬁcant increased HCC risk was found in Asians, hospital-based studies, and high quality studies.
  
  
  CONCLUSIONS
  The present meta-analysis suggests that the IL-12B+1188A/C polymorphism is a low-penetrant risk factor for HCC development, especially among Asians. Further large and well-designed studies are needed to confirm this association.
authors.affiliation: Department of Clinical Laboratory, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
authors.forename: Qiliu
authors.initials: Q
authors.lastname: Peng
authors.affiliation: Department of Clinical Laboratory, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
authors.forename: Xianjun
authors.initials: X
authors.lastname: Lao
authors.affiliation: Department of Occupational Health and Environmental Health, School of Public Health at Guangxi Medical University, Nanning, Guangxi, China.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Medicine Research, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
authors.forename: Ruolin
authors.initials: R
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China. Electronic address: qinxue919@126.com.
authors.forename: Xue
authors.initials: X
authors.lastname: Qin
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006801:Humans; D053762:Interleukin-12 Subunit p40 / Q000235:genetics*; D008113:Liver Neoplasms / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide
chemical_list: C500879:IL12B protein, human; D053762:Interleukin-12 Subunit p40