Polymorphisms A1026G and G369C of CDKN1A/p21 and p53 genes in lung cancer

In this study, we analyzed the polymorphisms of genes regulating the cell cycle and p53 CDKN1A/p21 as factors of genetic predisposition to lung cancer in patients with lung cancer. We examined 65 patients with lung cancer (average age 54±8 years) and 100 healthy blood donors (average age 52±6 years). Diagnosis of lung cancer was confirmed morphologically, endoscopically and radiologically. The study of these genes was performed by PCR/RFLP analysis. 72-G/C- polymorphism analysis of p53 gene has revealed a slight increase in the frequency of the variant G72C-genotype of the p53 gene in lung cancer patients compared with those in healthy (38 and 32% respectively, P = 0,695). We have analyzed two polymorphisms CDKN1A/p21: 1026 A/G and 369 G/C-polymorphism in the 5$'$-gene promoter. In analyzing the 1026-AG-p21 gene polymorphism was found halving the frequency of AG-genotype in lung cancer patients compared with those in healthy individuals (38 and 77%, respectively; OR = 0,72, CI 95% 0,081–3,95). The frequency of AA-genotype of p21 gene in patients and healthy was respectively 50 and 19% for the GG-genotype of p21 gene was respectively 10 and 4% (OR=5,39, CI 95% 1,27–24,29). This enabled us to assume that the AG-genotype performs protective and AA-genotype - the role of predisposing to cancer of the lung. The frequency of A-allele in lung cancer patients was higher than in healthy individuals (70 and 57,5%, respectively). OR of lung cancer for carriers of the A-allele was 1,72 (CI 95% 1,05-2,83). In the analysis of G369C-gene polymorphism in p21 is shown, the frequency of C-allele in lung cancer patients significantly exceeded that in healthy individuals (20,77 and 11%, respectively; OR=2,12 CI 95% 1,10-4,09).