Influence of a single-nucleotide polymorphism of the DNA mismatch repair-related gene exonuclease-1 (rs9350) with prostate cancer risk among Chinese people

In this study, we aimed to identify the influence of exonuclease 1 (EXO1) single-nucleotide polymorphism rs9350, which is involved in DNA mismatch repair, on prostate cancer risk in Chinese people. In our hospital-based case-control study, 214 prostate cancer patients and 253 cancer-free control subjects were enrolled from three hospitals in China. Genotyping for rs9350 was performed by the SNaPshot (R) method using peripheral blood samples. Consequently, a significantly higher prostate cancer risk was observed in patients with the CC genotype [odds ratio (OR)=1.678, 95 % confidence interval (CI)=1.130-2.494, P=0.010] than in those with the CT genotype. Further, the CT/TT genotypes were significantly associated with increased prostate cancer risk (adjusted OR=1.714, 95 % CI=1.176-2.500, P=0.005), and the C allele had a statistically significant compared with T allele (P=0.009) of EXO1 (rs9350). Through stratified analysis, significant associations were revealed for the CT/TT genotype in the subgroup with diagnosis age >72 (adjusted OR=1.776, 95 % CI=1.051-3.002, P=0.032) and in patients with localized disease subgroup (adjusted OR=1.798, 95 % CI=1.070-3.022, P=0.027). In addition, we observed that patients with prostate-specific antigen (PSA) levels of <= 10 ng/mL were more likely to have the CT/TT genotypes than those with PSA levels of >10 ng/mL (P=0.006). For the first time, we present evidence that the inherited EXO1 polymorphism rs9350 may have a substantial influence on prostate cancer risk in Chinese people. We believe that the rs9350 could be a useful biomarker for assessing predisposition for and early diagnosis of prostate cancer.