RU 10. IL-6 2174G > C polymorphism and cancer risk: A meta - analysis involving 29,377 cases and 37,739 controls

Interleukin-6 (IL-6) is a multifunctional cyto- kine involved in different physiologic and pathophysiologic processes and plays important roles in the etiology of cancer. The -174G[C polymorphism of the IL-6 gene influences IL-6 transcription and has been implicated in cancer risk . However, published data have been conflicting. To derive a more precise estimation of the relationship, a meta-analysis of 29,377 cancer cases and 37,739 controls from 50 published case-control studies was performed. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association between -174G[C polymorphism and cancer risk. Overall meta-analysis indicated that no association was found between -174G[C genotypes and cancer risk. However, the positive association was found in bladder cancer (OR=4.33, 95% CI:1.93-9.71 for CC vs. GC, OR=2.81, 95% CI:1.39-5.68 for CC vs. GG, and OR=2.19, 95% CI:1.32-3.64 for CC vs. GG/GC), and among Asians (OR=2.08, 95% CI:1.07-4.06 for CC vs. GG, and OR=2.20, 95% CI:1.02-4.74 for CC vs. GG/GC) and Af r icans (OR=1.61, 95% CI:1.07-2.42 for GC vs. GG). This metaanalysis showed the evidence that the -174G[C of the IL-6 gene was a low-penetrance suscepti-bility gene for bladder cancer. Further larger, preferably prospective studies are needed to confirm this relationship.