Vascular endothelial growth factor gene polymorphisms and gastric cancer risk: a meta-analysis

Purpose: Vascular endothelial growth factor (VEGF) plays important roles in the process of tumor growth and metastasis. Although the association between VEGF polymorphisms and gastric cancer risk has been extensively studied, available results remain controversial. To derive a convincing estimation of the relationship, a meta-analysis containing 6 VEGF (+936C/T, -634G/C, -460T/C, +1612G/A, -2578C/A and -1154G/A) gene polymorphisms was performed. Methods: We conducted a systematic search of PubMed and Chinese National Knowledge Infrastructure (CNKI) to select relevant articles. Nine available case-control studies with 2,281 gastric cancer cases and 2,820 healthy controls met the inclusion criteria. The odds ratio (OR) and 95% confidence interval (95% CI) were used to evaluate the strength of the association. Results: This meta-analysis indicated that the VEGF-634 G allele carrier represented a risk factor for gastric cancer (GG+GC vs CC: OR=1.23, 95%CI=1.02-1.49, p=0.03). The VEGF +1612G/A polymorphism was associated with risk of gastric cancer (G allele vs A allele: OR=0.62, 95%C1=0.49-0.79, p<0.0001; GG+GA vs AA: OR=0.16, 95%CI=0.05-0.51, p=0.002 and GA+AA vs GG : OR=1.57, 95%CI=1.21-2.04, p=0.008). For polymorphisms of VEGF +936C/T, -460C/T, -2578C/A, -1154G/A, no association was found with gastric cancer risk. Conclusion: Our meta-analysis suggests that VEGF-634 G allele carrier may increase gastric cancer risk, whereas the VEGF +1612 G/A G allele and G allele carrier may decrease the risk. No association between+936C/T, -460C/T, -2578C/A, -1154G/A polymorphisms and susceptibility to gastric cancer was found.