Relationship of IL-18 genetic polymorphism to cervical cancer risk: A meta-analysis

Published studies about the association between Interleukin-18 (IL-18) gene polymorphisms and cervical cancer susceptibility were inconsistent. A meta-analysis for the association between IL-18-607C/A (rs1946518) and risk of cervical cancer was carried out to collectively analyse existing comparative studies. PubMed, Embase, Science Citation Index (SCI), CNKI and Wanfang were researched on the associations between Interleukin-18 and cervical cancer risk. Five studies with 775 cervical cancer patients and 1004 controls met the criteria and included into this study. By meta-analysis analyses, we found that IL-18 rs1946518 CA and AA genotypes were not significantly associated with an increased risk of cervical cancer. The heterogeneities existed in the association between the IL-18 rs1946518 AA genotype and risk of cervical cancer in comparison to the CC genotype (P for heterogeneity<0.001, I2=87.2%). We found that the AA genotype of IL-18-607C/A rs1946518 was associated with a decreased risk of cervical cancer in studies with population-based design, when compared with the CC genotype (OR=0.19, 95% CI=0.04-0.98). In summary, our meta-analysis suggests that IL-18 polymorphism may not contribute to the development of cervical cancer, but the IL-18-607 AA genotype is associated with cervical cancer risk in studies with population-based design. Further studies with well study design and large sample size are greatly needed to confirm the association between IL-18-607C/A rs1946518 and cervical cancer risk.