OBJECTIVE: This systematic review and meta-analysis was undertaken to integrate previous findings and summarize the effect size of the association of interleukin-6 (IL-6) genetic polymorphism -174G/C with susceptibility to prostate cancer (PCa). METHODS: All eligible studies of IL-6 -174G/C polymorphism and PCa risk were collected from the following electronic databases: PubMed and the Cochrane Library, with the last report up to June 1, 2011. Statistical analyses were performed by Review Manage version 5.0 and Stata 10.0. RESULTS: A total of 7 independent studies, including 9,959 cases and 12,361 controls, were identified. When all studies were pooled, we did not detect a significant association of -174G/C polymorphism with PCa risk. When stratifying for race, similar results were obtained; evidence of a significant relation was absent in both Caucasians and the mixed population. After stratifying the studies by study types, -174G/C polymorphism was significantly associated with PCa risk when examining the contrast of CC + GC versus GG (OR = 1.44, 95% CI = 1.05-1.98, p = 0.03) in cohort studies but not in case-control studies. CONCLUSIONS: Our review suggest that -174G/C polymorphism is associated with an increased PCa risk in two cohort studies from one article. Additional well-designed studies are warranted to validate these findings.
OBJECTIVE: This systematic review and meta-analysis was undertaken to integrate previous findings and summarize the effect size of the association of interleukin-6 (IL-6) genetic polymorphism -174G/C with susceptibility to prostate cancer (PCa). METHODS: All eligible studies of IL-6-174G/C polymorphism and PCa risk were collected from the following electronic databases: PubMed and the Cochrane Library, with the last report up to June 1, 2011. Statistical analyses were performed by Review Manage version 5.0 and Stata 10.0. RESULTS: A total of 7 independent studies, including 9,959 cases and 12,361 controls, were identified. When all studies were pooled, we did not detect a significant association of -174G/C polymorphism with PCa risk. When stratifying for race, similar results were obtained; evidence of a significant relation was absent in both Caucasians and the mixed population. After stratifying the studies by study types, -174G/C polymorphism was significantly associated with PCa risk when examining the contrast of CC + GC versus GG (OR = 1.44, 95% CI = 1.05-1.98, p = 0.03) in cohort studies but not in case-control studies. CONCLUSIONS: Our review suggest that -174G/C polymorphism is associated with an increased PCa risk in two cohort studies from one article. Additional well-designed studies are warranted to validate these findings.
Authors: Paul J Dluzniewski; Ming-Hsi Wang; Siqun Lilly Zheng; Angelo M De Marzo; Charles G Drake; Helen L Fedor; Alan W Partin; Misop Han; M Daniele Fallin; Jianfeng Xu; William B Isaacs; Elizabeth A Platz Journal: Cancer Epidemiol Biomarkers Prev Date: 2012-08-02 Impact factor: 4.254