Association Between Genetic Polymorphism Of IL-6-174C/G And Susceptibility To Gastric Cancer:a Meta-analysis

Objective: To investigate association between-174C/G genetic polymorphism of interleukin-6(IL-6)and susceptibility to gastric cancer by conducting a meta-analysis.Methods: Such databases as PubMed,Embase,The Cochrane Library,Web of Science,CNKI,VIP,and Wanfang Data were searched from inception to January 2017 to collect case-control studies about the correlation between the-174C/G genetic polymorphism of IL-6 and gastric cancer.For the population genotype distributions of both the gastric cancer group and the control group,their odds ratios(OR)and 95% confidence intervals(CI)were taken as the effect indexes were applied to conducted meta-analysis in the homozygote comparison,heterozygous models,dominant models,recessive genetic models,and allelic genetic models.Two reviewers independently screened the literatures,extracted the data,and evaluated the quality of the included studies.The meta-analysis was performed using Stata 12.0 software.Results: Thirteen articles were included in the final meta-analysis,covering a total of 2062 gastric cancer cases and 3152 controls.The results of meta-analysis showed that there was no correlation between the IL-6-174C/G genetic polymorphism and the risk of gastric cancer [CC vs.GG:OR=1.33,95% CI(0.92,1.94),P=0.129;GC vs.GG:OR=1.32,95% CI(0.96,1.82),P=0.091;CC+CG vs.GG:OR=1.32,95% CI(0.97,1.80),P=0.082;CG+GG vs.CC:OR =0.89,95% CI(0.67,1.17),P=0.395;C vs.G:OR=1.22,95% CI(0.98,1.54),P=0.081].But the subgroup analysis showed there was a significant association between the IL-6-174 C/G genetic polymorphism and the gastric cancer in the Asians [CC vs.GG:OR =1.80,95% CI(1.29,2.50),P =0.001;GC vs.GG:OR =1.52,95% CI(1.04,2.24),P =0.032;CC+CG vs.GG:OR =1.63,95% CI(1.18,2.26),P =0.003;C vs.G:OR =1.59,95% CI(1.24,2.03),P =0.000],except for the implicit gene model[OR =0.60,95% CI(0.44,0.83),P =0.002].However,no association was found in the Europeans [CC vs.GG:OR =1.12,95% CI(0.66,1.91,P =0.663);GC vs.GG:OR =1.23,95% CI(0.76,1.98),P =0.407;CC+CG vs.GG:OR =1.16,95% CI(0.73,1.85),P =0.533;CG+GG vs.CC: OR =1.07,95% CI(0.78,1.47),P =0.684;C vs.G:OR=1.04,95% CI(0.78,1.41),P =0.773].Conclusions:IL-6-174C/G genetic polymorphism is associated with susceptibility to gastric cancer in the Asians,which is not associated with susceptibility to gastric cancer in the Europeans.