The role of p21 3'UTR gene polymorphism in the risk of prostate cancer: a pilot study.

The cell cycle regulator p21 plays an important role in regulating critical cell activities including cell cycle control, DNA repair and apoptosis. Consequently, it may affect the efficacy of the response to DNA damage and tumor development. The aim of our study was to evaluate the frequencies of the p21 C70T polymorphism, the association between this genetic variant and smoking status, and the serum prostate-specific antigen (PSA) levels and Gleason score in 118 prostate cancer patients and 130 males routinely screened for prostate cancer in the Slovak population. Blood samples were collected from all individuals for DNA isolation, used for subsequent genotyping assays via PCR-RFLP methods. Overall, we did not observe any significant association between this polymorphism and prostate cancer risk. An analysis of the association between the p21 genotypes and smoking was then conducted. Among smokers, CC and CT genotypes were associated with a non­significant increased risk (OR=1.48; 95% CI, 0.80-2.76 and OR=1.15; 95% CI, 0.27­4.77, respectively; p>0.05) in comparison to non-smokers with the CC genotype. Patients with a CT genotype and serum PSA levels≥10 ng/ml had an 84% decrease in prostate cancer risk (OR=0.16; 95% CI, 0.03-0.75; p<0.05) compared to cases with serum PSA levels <10 ng/ml and the CC genotype. No significant association was detected between Gleason score and prostate cancer risk. Based on these results, we concluded that the p21 C70T polymorphism is associated with decreased risk of prostate cancer in Slovak men. To confirm these findings, a systematic approach is required to identify sequence variants in this and other related genes, and subsequently, to test for an association between such variants, smoking status and tumor-specific clinicopathological characteristics in large samples.