Genetic polymorphism of epidermal growth factor 61A>G and cancer risk: A meta-analysis

Background: Numerous studies have investigated the risk of cancer associated with the polymorphism of epidermal growth factor (EGF) 61A>G, but the results have been inconsistent. We performed this meta-analysis to drive a more precise estimation of association between this polymorphism and risk of cancer. Methods: Electronic searches of PubMed and EMBASE were conducted to select studies. Case-control studies containing available genotype frequencies of EGF 61A>G were chose, and Odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of this association. Results: 23 case-control studies including 5578 cases and 7306 controls were identified. This meta-analysis showed significant effect of EGF 61A>G on cancer risk (GG vs. AA: OR=1.34, 95%CI=1.05–1.72; GG vs. GA+AA: OR=1.23, 95%CI=1.03–1.47; GG+GA vs. AA: OR=1.18, 95%CI=1.02–1.38). In subgroup analysis, significant increased risk was found in gastric cancer and glioma in additive model (OR=1.54, 95%CI=1.13–2.12; OR=1.69, 95%CI=1.21–2.37) and in recessive model (OR=1.29, 95%CI=1.10–1.52; OR=1.54, 95%CI=1.16–2.04). Conclusion: This meta-analysis suggested that the EGF 61G allele is a risk factor of cancer, especially for gastric cancer and glioma.