Analysis of TP53 polymorphisms in North Indian sporadic esophageal cancer patients.

BACKGROUND To investigate the relationship of five TP53 polymorphisms (p.P47S, p.R72P, PIN3 ins16bp, p.R213R and r.13494g>a) with the esophageal cancer (EC) risk in North Indians. MATERIALS AND METHODS Genotyping of p.P47S, p.R72P, PIN3 ins16bp, p.R213R and r.13494g>a polymorphisms of TP53 in 136 sporadic EC patients and 136 controls using polymerase chain reaction and PCR-RFLP. RESULTS The frequencies of genotype RR, RP and PP of p.R72P polymorphism were 16.91 vs 26.47%, 58.82 vs 49.27% and 24.27 vs 24.27% among patients and controls respectively. We observed significantly increased frequency of RP genotype in cases as compared to controls (OR=1.87, 95% CI, 1.01-3.46, p=0.05). The frequencies of genotype A1A1, A1A2 and A2A2 of PIN3 ins16bp polymorphism were 69.12 vs 70.59%, 27.20 vs 25% and 3.68 vs 4.41% among patients and controls. There was no significant difference among genotype and allele distribution between patients and controls. The frequencies of genotype GG, GA and AA of r.13494g>a polymorphism were 62.50 vs 64.70%, 34.56 vs 30.15% and 2.94 vs 5.15% among patients and controls respectively. No significant difference between genotype and allele frequency was observed in the patients and controls. For p.P47S and p.R213R polymorphisms, all the cases and controls had homozygous wild type genotype. The RP-A1A1-GG genotype combination shows significant risk for EC (OR=2.01, 95%CI: 1.01-3.99, p=0.05). CONCLUSIONS Among the five TP53 polymorphisms investigated, only p.R72P polymorphism may contributes to EC susceptibility.