Document Type: Systematic Review and Meta-analysis
Department of Clinical Laboratory, First Affiliated Hospital of Soochow University, Suzhou, China.
Central Laboratory of Pediatric Research Institute, Affiliated Children’s Hospital of Soochow University, Suzhou, China.
Background: Accumulating evidence shows that cytokines play an important role in the proliferation of prostate
cancer. This research is trying to determine that IL-18 -607 C/A polymorphism confers susceptibility to prostate cancer.
Methods: Meta-analysis was used to collect data. The relevant studies were identified through a comprehensive search
from PubMed, Excerpta Medica Database (EMBASE), Web of Science, and Chinese Biomedical Literature Database
(CBM) to obtain related studies published up to December 6, 2017. The association between interleukin (IL)-18 -607 C/A
polymorphism and prostate cancer risk was assessed by odds ratios (ORs) together with their 95% confidence intervals
(CIs). Results: Nine case-control studies from 6 articles were eventually identified. In the overall population, there is a
significant association between IL-18 -607 C/A polymorphism and prostate cancer risk in recessive (CC versus CA/AA:
OR = 0.20, 95% CI = 0.15-0.27, P = 0.000) or dominant (CC/CA versus AA:OR = 0.42, 95% CI = 0.30–0.57, P = 0.000)
models. In the sub-group analysis according to ethnicity, for Asians, IL-18 -607 C/A polymorphism was significantly
associated with prostate cancer in allele contrast (C versus. A: OR=0.82, 95%CI=0.70-0.97, P=0.019), homozygote
(CC versus. AA: OR=0.68, 95%CI=0.50-0.92, P=0.013), recessive (CC versus. CA/AA: OR=0.19, 95%CI=0.13-0.27,
P=0.000), and dominant (CC/CA versus. AA: OR=0.37, 95%CI=0.28-0.48, P=0.000) models, for Caucasians, IL-18
-607 C/A polymorphism was significantly associated with prostate cancer risk in allele contrast (C versus. A: OR=1.27,
95%CI=1.02-1.58, P=0.033), homozygote (CC versus. AA: OR=1.86, 95%CI=1.19-2.91, P=0.007) and recessive (CC
versus. CA/AA: OR=0.25, 95%CI=0.19-0.33, P=0.000) models. Conclusion: This meta-analysis has shown that IL-18
-607 C/A polymorphism contributes to a decreased risk of prostate cancer risk in the Asian population but an increased
risk in the Caucasian population.