Association between PIN1 promoter polymorphisms and risk of nasopharyngeal carcinoma

Peptidylprolyl cis/trans isomerase, NIMA-interacting 1 (PIN1) plays an important role in cell transformation and oncogenesis. Association between PIN1 promoter polymorphisms and cancer risk was reported in several cancers. This study aimed to evaluate the association between two single nucleotide polymorphisms (SNPs, -667T>C, rs2233679 and -842G>C, rs2233678) on PIN1 promoter and risk of nasopharyngeal carcinoma (NPC). The two SNPs were genotyped using polymerase chain reaction-restriction fragment length polymorphism in a total of 334 native Chinese subjects consisting of 178 cases and 156 controls. The results indicated that the -667CT heterozygote and -667CC homozygote exhibited a significantly decreased risk of nasopharyngeal carcinoma when compared with -667TT homozygote (OR = 0.639, 95% CI = 0.452-0.903, p = 0.011 for -667CT; and OR = 0.441, 95% CI = 0.213-0.915, p = 0.038 for -667CC, respectively). In the -842G>C polymorphism, compared with -842GG homozygote, only -842CG heterozygote but not -842CC homozygote had a significantly decreased risk of nasopharyngeal carcinoma (OR = 0.465, 95% CI = 0.249-0.871, p = 0.010). Genotype in the two SNPs in patients showed no significant associations with the clinicopathologic features examined. Our study showed that the minor genotypes of PIN1 promoter (-667CT, -667CC and -842CG) were associated with decreased risk of NPC in a Chinese population, suggested that PIN1 promoter polymorphisms might play an important role in NPC carcinogenesis.