Single Nucleotide Polymorphisms of PIN1 Promoter Region and Cancer Risk: Evidence from a Meta-Analysis

Background: Peptidylprolyl cis/trans isomerase NIMA-interacting 1 (PIN1) is involved in the process of tumorigenesis. The two single nucleotide polymorphisms (-677T>C, -842G>C) in the PIN1 promoter region have been suspected of being associated with cancer risk for years, but the conclusion is still inconclusive. Methods: Eligible case-control studies were retrieved by searching databases and references of related reviews and studies. Genotype distribution data, adjusted odds ratios (ORs) and 95% confidence (CIs) intervals were extracted to calculate pooled ORs. Results: A total of 4619 cancer cases and 4661 controls were included in this meta-analysis. Overall, the PIN1 -667T>C polymorphism was not associated with cancer risk, while the -842C allele was significantly associated with reduced cancer risk (CC+GC vs. GG, OR = 0.725, 95% CI: 0.607-0.865; P-heterogeneity = 0.012 and GC vs. GG: OR = 0.721, 95% CI: 0.591-0.880; P-heterogeneity = 0.003). Results from genotype distribution data were in agreement with those calculated with adjusted ORs and 95% CIs. No publication bias was detected. Conclusions: Results of this meta-analysis suggest that the PIN1 -842G>C polymorphism is associated with decreased cancer risk, but that the -667T>C polymorphism is not.