Associations between interleukin-6 gene-174 C/G and -572 C/G polymorphisms and the risk of gastric cancer: A meta-analysis

Background and Objectives Epidemiological studies have evaluated the associations between interleukin-6 (IL-6) gene -174?C/G (rs1800795) and -572?C/G (rs1800796) polymorphisms and gastric cancer (GC) risk, but results and conclusions remain controversial. In order to derive a more precise estimation of the associations, we performed this meta-analysis. Methods A meta-analysis was conducted to estimate the associations between IL-6 gene -174?C/G and -572?C/G polymorphisms and GC risk. Results Nine articles involving 13 studies were included in the final meta-analysis, covering a total of 1,581 GC cases and 2,563 controls. For IL-6 gene -174?C/G polymorphism, nine studies were combined showing no evidence for associations between IL-6 gene -174?C/G polymorphism and GC risk. For IL-6 gene -572?C/G polymorphism, four studies were combined. There was also lack of evidence for significant association between IL-6 gene -572?C/G polymorphism and GC risk. In addition, the similar results were obtained in the subgroup analyses and cumulative meta-analysis. Conclusions The present meta-analysis suggests that IL-6 gene -174?C/G and -572?C/G polymorphisms are not associated with GC risk. However, due to the small subjects included in analysis and the selection bias in some studies, the results should be interpreted with caution. J. Surg. Oncol. 2012; 106: 987993. (c) 2012 Wiley Periodicals, Inc.