Association between IL13 gene polymorphisms and susceptibility to cancer: A meta-analysis

Background/aims: Interleukin-13 (IL13) is an immunoregulatory cytokine which plays an important role in carcinogenesis through affecting tumor immunosurveillance. Many studies had reported the influence of IL13 rs1800925 and rs20541 polymorphisms on cancer risk, however, with inconclusive results. The aim of the present study was to conduct a meta-analysis to clarify the relationship. Methods: Twenty studies including a total of 6713 cancer cases and 8693 controls for IL13 rs20541 polymorphism and 4081 cancer cases and 6202 controls for IL13 rs1800925 polymorphism were included in the meta-analysis. Data were extracted from these studies and odds ratios with corresponding 95% confidence intervals were computed to estimate the strength of the association. Results: Overall, the IL13 rs20541 polymorphism were associated with significantly decreased cancer risk in all genetic models (AA vs. GG: OR = 0.82, 95%CI = 0.71-0.95; GA vs. GG: OR = 0.92, 95%CI = 0.85-0.99; GA/AA vs. GG: OR= 0.90, 95%CI = 0.85-0.97; AA vs. GG/GA: OR= 0.85, 95CI% = 0.74-0.98). In the stratified analyses, significant effects were found among European populations, studies with population-based controls and studies of glioma. No influence of the IL13 rs1800925 polymorphism on the overall cancer risk was observed. However, in the stratified analyses, we found the IL13 rs1800925 polymorphism was significantly associated with decreased risk for glioma (CT vs. TT: OR= 0.72, 95%CI = 0.55-0.93; CT/TT vs. TT: OR = 0.76, 95%CI = 0.62-0.89). Conclusion: Our meta-analysis suggests that the IL13 rs20541 polymorphism contributes to susceptibility to cancer, especially for glioma; and the IL13 rs1800925 polymorphism may be associated with glioma risk. (C) 2012 Elsevier B.V. All rights reserved.