title: Epidermal growth factor gene polymorphism and risk of hepatocellular carcinoma: a meta-analysis.
abstract: BACKGROUND
  Hepatocarcinogenesis is a complex process that may be influenced by many factors, including polymorphism in the epidermal growth factor (EGF) gene. Previous work suggests an association between the EGF 61*A/G polymorphism (rs4444903) and susceptibility to hepatocellular carcinoma (HCC), but the results have been inconsistent. Therefore, we performed a meta-analysis of several studies covering a large population to address this controversy.
  
  
  METHODS
  PubMed, EMBASE, Google Scholar and the Chinese National Knowledge Infrastructure databases were systematically searched to identify relevant studies. Data were abstracted independently by two reviewers. A meta-analysis was performed to examine the association between EGF 61*A/G polymorphism and susceptibility to HCC. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated.
  
  
  RESULTS
  Eight studies were chosen in this meta-analysis, involving 1,304 HCC cases (1135 Chinese, 44 Caucasian and 125 mixed) and 2,613 controls (1638 Chinese, 77 Caucasian and 898 mixed). The EGF 61*G allele was significantly associated with increased risk of HCC based on allelic contrast (OR = 1.29, 95% CI = 1.16-1.44, p<0.001), homozygote comparison (OR = 1.79, 95% CI = 1.39-2.29, p<0.001) and a recessive genetic model (OR = 1.34, 95% CI = 1.16-1.54, p<0.001), while patients carrying the EGF 61*A/A genotype had significantly lower risk of HCC than those with the G/A or G/G genotype (A/A vs. G/A+G/G, OR = 0.66, 95% CI = 0.53-0.83, p<0.001).
  
  
  CONCLUSIONS
  The 61*G polymorphism in EGF is a risk factor for hepatocarcinogenesis while the EGF 61*A allele is a protective factor. Further large and well-designed studies are needed to confirm this conclusion.
authors.affiliation: Hepatobiliary Surgery Department, Guangxi Medical University, Tumor Hospital, Nanning, People's Republic of China.
authors.forename: Jian-Hong
authors.initials: JH
authors.lastname: Zhong
authors.forename: Xue-Mei
authors.initials: XM
authors.lastname: You
authors.forename: Wen-Feng
authors.initials: WF
authors.lastname: Gong
authors.forename: Liang
authors.initials: L
authors.lastname: Ma
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Qin-Guo
authors.initials: QG
authors.lastname: Mo
authors.forename: Liu-Cheng
authors.initials: LC
authors.lastname: Wu
authors.forename: Jun
authors.initials: J
authors.lastname: Xiao
authors.forename: Le-Qun
authors.initials: LQ
authors.lastname: Li
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000208:ethnology / Q000235:genetics*; D016022:Case-Control Studies; D004815:Epidermal Growth Factor / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006761:Hospitals; D006801:Humans; D008113:Liver Neoplasms / Q000208:ethnology / Q000235:genetics*; D011110:Polymorphism, Genetic; D017594:Publication Bias
chemical_list: D004815:Epidermal Growth Factor