Association between an insertion/deletion polymorphism in IL-1A gene and cancer risk: a meta-analysis

PURPOSE: Previous studies have reported the association of an insertion/deletion (Ins/Del) polymorphism (rs3783553) in the 3′ untranslated region of interleukin-1A (IL-1A) with the risk of cancer, such as oral squamous cell carcinoma, nasopharyngeal carcinoma, and cervical carcinoma. However, the results are still inconsistent. The present meta-analysis aimed to clarify the association of IL-1A rs3783553 polymorphism with cancer risk. METHODS: All eligible studies were selected from PubMed, Web of Science, and Chinese National Knowledge Infrastructure up to September 2, 2015. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate cancer risk. RESULTS: A total of ten case–control studies with 4,514 cases and 6,689 controls were included this meta-analysis. We found that IL-1A rs3783553 polymorphism was significantly associated with cancer risk (Ins/Ins + Ins/Del vs Del/Del: OR =0.79, 95% CI =0.67–0.92; Ins/Ins vs Del/Del: OR =0.61, 95% CI =0.47–0.79; Ins/Ins vs Ins/Del + Del/Del: OR =0.67, 95% CI =0.55–0.83; Ins vs Del: OR =0.81, 95% CI =0.72–0.92). In the stratified analyses, significant effects were found among Asian populations (Ins/Ins + Ins/Del vs Del/Del: OR =0.81, 95% CI =0.69–0.95) and cervical carcinoma (Ins/Ins vs Del/Del: OR =0.51, 95% CI =0.34–0.76; Ins/Ins vs Ins/Del + Del/Del: OR =0.52, 95% CI =0.35–0.78). CONCLUSION: Our meta-analysis suggests that the IL-1A rs3783553 polymorphism contributes to susceptibility to cancer. However, well-designed studies with larger sample sizes are required to verify the results.