To data, epidemiological studies have assessed the association between peptidyl-propyl-
cis/trans isomerase 1 (PIN1) gene polymorphisms and
cancer risk, including
breast cancer,
hepatocellular carcinoma,
lung cancer,
esophageal cancer,
head and neck squamous cell carcinoma, and laryngeal
squamous cell cancer. However, the results of these studies remain controversial. We aimed to examine the associations between two SNPs (rs2233678 and rs2233679) of PIN1 gene and
cancer risk by conducting a meta-analysis of case-control studies. A total of seven publications were included in this meta-analysis for both rs2233678 and rs2233679. Overall, rs2233678 polymorphism was found to be associated with decreased
cancer risk in four genetic models (C-allele vs. G-allele: odd ratio (OR) = 0.73, 95% confidence interval (CI): 0.60-0.88; CC vs. GG: OR = 0.55, 95% CI: 0.36-0.84; CC+CG vs. GG: OR = 0.72, 95% CI 0.58-0.90; CC vs. CG+GG: OR = 0.58, 95% CI 0.38-0.89). However, the rs2233679 polymorphism of PIN1 gene did not appear to have an influence on caner susceptibility. In the subgroup analysis by
cancer type, we observed that the PIN1 rs2233678 polymorphism was significantly associated with decreased
breast cancer risk (C-allele vs. G-allele: OR = 0.73, 95% CI: 0.60-0.89; CC+CG vs. GG: OR = 0.71, 95% CI 0.57-0.89). Further subgroup analyses showed that the PIN1 rs2233678 polymorphism was associated with decreased
cancer risk among Asian people (C-allele vs. G-allele: OR = 0.63, 95% CI: 0.51-0.79; CC vs. GG: OR = 0.44, 95% CI: 0.25-0.80; CC+CG vs. GG: OR = 0.63, 95% CI 0.50-0.79; CC vs. CG+GG: OR = 0.47, 95% CI 0.26-0.86). In conclusion, PIN1 rs2233678 polymorphism might be a potential
biomarker for
cancer risk among Asians, especially for
breast cancer. Further large and well-designed studies are needed to confirm this conclusion.