The association between interleukin-1β gene polymorphisms and the risk of breast cancer: a systematic review and meta-analysis

IntroductionIt is reported that there is a close association between interleukin-1β (IL-1β) gene polymorphisms and breast cancer risk. However, the results remain controversial.Material and methodsEligible published articles were searched in PubMed, Embase, and Web of Science databases up to June 2018. Odds ratios with 95% confidence intervals were used to identify potential links between IL-1β genetic polymorphisms and the risk of breast cancer.ResultsFrom our results, we found that three common polymorphisms in IL-1β (rs16944, rs1143634, rs1143627) had no significant associations with breast cancer risk in all genetic models. Based on the analysis from ethnic subgroups, there was a higher risk of breast cancer for rs16944 polymorphism in the recessive model and heterozygous model among Asians (TT vs. CC+CT: 1.229, 95% CI: 1.063–1.422, p = 0.005; TT vs. CT: 1.211, 95% CI: 1.057–1.388, p = 0.006). For the rs1143627 polymorphism, a significantly decreased breast cancer risk was observed in the dominant model only in Asians (CT+TT vs. CC: OR = 0.944, 95% CI: 0.897–0.994, p = 0.027). After stratifying patients according to the menopausal state, we found that polymorphism of rs1143627 correlated with reduced breast cancer risk among post-menopausal women in three genotype models: allele, recessive model and homozygous model (T vs C: 0.859, 95% CI: 0.753–0.98, p = 0.024; TT vs. CC+CT: 0.727, 95% CI: 0.576–0.918, p = 0.007; TT vs. CC: 0.743, 95% CI: 0.626–0.882, p = 0.001). As for other analyses with reference to source of controls and genotyping methods, no significant association between IL-1β polymorphism and breast cancer risk was demonstrated.ConclusionsThe rs16944 and rs1143627 polymorphisms are significantly associated with the risk of breast cancer only in Asian people and in post-menopausal women respectively.