[Genetic polymorphisms in the promoter region of cyclooxygenase-2 and their association with risk of gastric cancer].

Objective To examine the genetic polymorphisms in the promoter region of cyclooxyge- nase-2 (COX-2) and evaluate their association with the risk of gastric cancer. Methods Single-strand conformational polymorphism and DNA sequencing were used to screen the genetic variants of the COX-2 promoter region. Total 323 patients with gastric cancer and 646 frequency-matched controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism method. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by logistic regression. Haplotype frequency was estimated using Haplo.stat software. Results Three single nucleotide polymorphisms,including -1290AG,-1195GA,and -765G C were identified in the promoter of COX-2. Case-control analysis showed an increased risk of developing gastric cancer for the -1290AG (OR 1.64; 95% CI 1.03-2.61),-1195AA (OR 2.68; 95% CI 1.65-4.33),and -765CG (OR 2.66; 95% CI 1.53-4.64) genotype carriers,respectively,compared with noncarriers. A greater risk of developing gastric cancer was observed for the A_ -1290 -A_ -1195 -C_ -765 haplotype compared with the A_ -1290 -G_ -1195 -G_ -765 haplotypes (OR 11.80; 95% CI 2.43-57.25). Conclusion Genetic polymorphisms in COX-2 promoter region may play a role in gastric carcinogenesis.