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.