Supplementary Material for: Meta-Analysis of the Association between the IL-12B +1188 A/C Polymorphism and Cancer Risk

Background: Because of inconsistent results from previous studies on the association of IL-12B +1188 A/C polymorphism with cancer risk, a meta-analysis was performed to assess the association. Materials and Methods: A literature search was performed to identify all relevant studies to May 31, 2012, with a restriction to English and Chinese publications. Pooled data were estimated using a random-effects model. Results: 17 publications were included in the meta-analysis. The results indicated that the polymorphism was significantly associated with a decreased risk for overall cancer (odds ratio (OR), 95% confidence interval (CI): 0.86, 0.76-0.97, p = 0.007; 0.80, 0.68-0.95, p = 0.012; and 0.88, 0.78-0.99, p = 0.032, respectively for dominant model, recessive model, and allele analysis) or nasopharyngeal cancer and hepatocellular carcinoma. This association was also found in Asians (OR, 95% CI: 0.89, 0.80-0.99, p = 0.031; 0.82, 0.68-0.98, p = 0.027; and 0.89, 0.80-1.00, p = 0.047, respectively for dominant model, recessive model, and allele analysis), but not in Europeans and Americans. Conclusion: The present study indicates that the IL-12B +1188 A/C polymorphism could play a protective role in the development of cancer. More investigations involving various cancer types among various populations are needed.