Effects of interleukin-10 polymorphisms (rs1800896, rs1800871, and rs1800872) on breast cancer risk: Evidence from an updated meta-analysis

Background: The associations between Interleukin-10 (IL-10) polymorphisms and breast cancer (BC) risk are inconsistent. This study was aimed to evaluate the relationship between IL-10 polymorphisms (rs1800896, rs1800871, and rs1800872) and BC risk. Methods: Databases, including PubMed, Web of Knowledge, Embase, and Chinese National Knowledge Infrastructure, were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the strength of associations. Results: A total of 12 studies (4743 cancer cases and 5120 case-free controls) were eligible for meta-analysis. There were nine studies with 1851 cases and 1910 controls for rs1800896, six studies with 1034 cases and 1173 controls for rs1800871, and seven studies with 3637 cases and 3391 controls for rs1800872. Meta-analysis showed that rs1800896 and rs1800871 polymorphisms had no association with BC risk (for rs1800896: OR=1.060, 95% CI=0.785-1.432 in the dominant model, and OR=1.152, 95% CI=0.958-1.386 in the recessive model; for rs1800871: OR=0.952, 95% CI=0.859-1.056 in the dominant model, and OR=0.892, 95% CI=0.741-1.072 in the recessive model). However, rs1800872 polymorphism has association with BC risk based on the recessive model (OR=0.80, 95% CI=0.73-0.88). In the stratified analysis, when analyzed by the recessive model (CC vs. AA+AC), the ORs were 0.75 (95% CI=0.68-0.83) (p<0.00001) among Caucasians and 1.17 (95% CI=0.88-1.55) (p=0.27) among Asians. These results suggested that the CC homozygote has a 25% decreased risk of BC compared with those individuals with AA and AC genotypes in Caucasians. Conclusions: This meta-analysis showed that IL-10 rs1800896 and rs1800871 polymorphisms had no association with BC risk, while rs1800872 polymorphism had a decreased risk of BC in Caucasians.