OBJECTIVE: Published results on association between eNOS polymorphisms and cancer risk are conflicting. We aimed to investigate the association and give an overall understanding of possible risk role of eNOS. METHOD: We searched PubMed and EMbase databases. The pooled ORs and 95% CIs for the association between eNOS polymorphisms and cancer risk was estimated using fixed- or random- effect model. Subgroup and sensitivity analyses were employed for further analysis. RESULTS: The Overall results showed no significant association of G894T polymorphism with cancer susceptibility (T vs. G: OR 1.02, 95% CI 0.97 to 1.07; TT+GT vs. GG: OR 1.02, 95% CI 0.96 to 1.09; TT vs. GT+GG: OR 1.05, 95% CI 0.93 to 1.17). For the T-786C polymorphism, pooled OR under recessive model suggested that CC genotype was significantly associated with increased cancer risk (CC vs. TC+TT: OR 1.31, 95% CI 1.09 to 1.57). For the 4b/a polymorphism, pooled OR for recessive model suggested positive result of 4a/4a genotype (aa vs. ba+bb: OR 1.64, 95% CI 1.11 to 2.43). In subgroup analysis by ethnicity, significant association was found in Caucasians in recessive model but not in Asians for T-786C and 4b/a, respectively. In subgroup analysis by cancer types, significant result was obtained for breast cancer in recessive model for the T-786C polymorphism. CONCLUSION: The eNOS G894T polymorphism may not be a major risk factor for most types of cancers. The CC of T-786C polymorphism and 4a/4a of 4b/a polymorphism are associated with cancer risk, especially in Caucasians. There is significant association between T786C polymorphism and breast cancer risk. More data are needed to verify these results.
OBJECTIVE: Published results on association between eNOS polymorphisms and cancer risk are conflicting. We aimed to investigate the association and give an overall understanding of possible risk role of eNOS. METHOD: We searched PubMed and EMbase databases. The pooled ORs and 95% CIs for the association between eNOS polymorphisms and cancer risk was estimated using fixed- or random- effect model. Subgroup and sensitivity analyses were employed for further analysis. RESULTS: The Overall results showed no significant association of G894T polymorphism with cancer susceptibility (T vs. G: OR 1.02, 95% CI 0.97 to 1.07; TT+GT vs. GG: OR 1.02, 95% CI 0.96 to 1.09; TT vs. GT+GG: OR 1.05, 95% CI 0.93 to 1.17). For the T-786C polymorphism, pooled OR under recessive model suggested that CC genotype was significantly associated with increased cancer risk (CC vs. TC+TT: OR 1.31, 95% CI 1.09 to 1.57). For the 4b/a polymorphism, pooled OR for recessive model suggested positive result of 4a/4a genotype (aa vs. ba+bb: OR 1.64, 95% CI 1.11 to 2.43). In subgroup analysis by ethnicity, significant association was found in Caucasians in recessive model but not in Asians for T-786C and 4b/a, respectively. In subgroup analysis by cancer types, significant result was obtained for breast cancer in recessive model for the T-786C polymorphism. CONCLUSION: The eNOSG894T polymorphism may not be a major risk factor for most types of cancers. The CC of T-786C polymorphism and 4a/4a of 4b/a polymorphism are associated with cancer risk, especially in Caucasians. There is significant association between T786C polymorphism and breast cancer risk. More data are needed to verify these results.