A p53 genetic polymorphism of gastric cancer: Difference between early gastric cancer and advanced gastric cancer

Aim: To investigate the role of the polymorphism of p53 codon 72 in early gastric cancer (EGC) and advanced gastric cancer (AGC) in Korean patients. Methods: DNA was extracted from blood samples of gastric cancer patients (n = 291) and controls (n = 216). In the p53 codon 72 genotypes were determined by PCR RFLP. Results: Patients with gastric cancer had a significantly higher frequency of the homozygous proline (Pro) allele than the control (P = 0.032). Patients with AGC had a significantly higher frequency of the Arg/Arg (arginine) allele (P = 0.038) than EGC and a similar Pro/Pro allele. The signet ring cell type had a higher frequency of the Pro/Pro allele than other types (P = 0.031). The Pro/Pro genotype carries a 3.9-fold increased risk of developing gastric cancer (95% CI, 1.3-15.4, P = 0.039) when compared to Arg/Arg and Arg/Pro genotypes and to develop EGC is a 5.25 fold increased risk (95% CI, 1.8-19.6, P = 0.021). Conclusion: The Pro/Pro genotype of the p53 codon 72 polymorphism carries a higher risk for gastric cancer in general and is also associated with a much higher risk for EGC than AGC.