Study On The Relationship Among Genetic Polymorphisms Of COX-2 And P53, H.pylori Infection And Susceptibility To Gastric Cancer In High Incidence Area

Study on the relationship among genetic polymorphisms of COX-2 and P53, H.pylori infection and susceptibility to gastric cancer in high incidence areaObjective 1.To study the distribution of COX-2 -899G＞C,587G＞A and 53CD72 G＞C gene polymorphisms among patients with gastric cancer and patients with precancerous lesion and health control in hight evidenve area,Hexi,of Gansu Province in China.2.To investigate the relationship among COX-2 -899G＞C,587G＞A and P53 CD72 G＞C gene polymorphisms,H.pylori infection and susceptibility to gastric cancer in hight evidenve area,Hexi,of Gansu Province in China.Methods Subects(in Hexi area)were divided into three groups.140 gastric cancer patiens,110 precancerous lesion patients and 125 control subjects were enrolled.Patients with gastric cancer were recruited by pathological diagnosis.Patients with precancerous lesion were screened by gastroscope biopsy and pathological diagnosis.The control subjects were excluded gastric disease by gastroscope.COX-2 -899G＞C,COX-2 codon 587G＞A and P53 codon Arg72Pro polymorphism was analyzed by PCR-TaqMan probes. H.pylori in gastric mucosa was detected by Warhin-Starry silver staining.The results were analyzed by SPSS13.0.Result The frequency of COX-2 -899C carrier genotype in gastric cancer patients was not only significantly higher than that in control health subjects(P=0.029,OR=1.956,95% CI:1.067～3.586),but also significantly higher than that in gastric precancerous lesion patients(P=0.027,OR=2.038,95%CI:1.078～3.854).The distribution of COX-2 -899C carrier genotype was not significantly different between gastric precancerous lesion patients and healthy subjects(P＞0.05).Stratification analysis showed that COX-2 -899C carrier genotype with Hp positive infection could increase the susceptibility to gastric cancer(OR:2.471,95%CI:1.076～5.675,P=0.030)and increased risk for the progression of gastric precancerous lesion into gastric carcinoma(OR:2.246,95%CI: 1.031～4.895,P=0.039),and also showed that COX-2 -899C carrier genotype with Hp positive infection was no statistically significant differences(P＞0.05)between gastric precancerous lesion patients and health subjects.The distribution of COX-2 codon587G＞A was not statistically significantly different (P＞0.05)among the gastric patients,gastric precancerous lesion patients and health subjects.When stratified by smoking status,H.pylory infection and family history of gastric cancer,the distribution of COX-2 codon587G＞A was also not significantly different(P＞0.05)among the gastric patients,gastric precancerous lesion patients and health subjects.Compared with Arg/Arg genotype,the frequency of P53codon Pro genotype(Arg /Pro and Pro/Pro genotypes)in gastric cancer patients was statistically significantly higher than that in control health subjects(OR:1.846,95%CI:1.006-3.387,P=0.046).However,no statistically significant differences were observed(P＞0.05)when we evaluated the distribution of Pro genotype between gastric precancerous lesion patients and health subjects or between gastric precancerous lesion patients and gastric cancer.Stratification analysis indicated that Pro genotype with H.pylory infection or with smoking increased the risk for gastric cancer when compared gastic cancer with health subjects,and their OR value was 2.663(1.193～5.946),2.415(1.027～5.676),respectively.Conclusion 1.The COX-2-899 C carrier genotype maybe increase the susceptibility to gastric cancer in the high incidence area,Hexi,of Gansu Province in China.In addition, COX-2-899C carrier genotype and H.pylori positive infection are correlation to gastric cancer.2.The COX-2 -899C carrier genotype may increase risk for the progression of gastric precancerous lesion into gastric carcinoma in the high incidence Hexi area of Gansu Province in China.3.The polymorphisms of COX-2 codon 587 G＞A had no relationship with gastric cancer in the high incidence Hexi area of Gansu Province in China.4.P53codon Pro genotype may be related with the risk of gastric cancer in the high incidence Hexi area of Gansu in China and may also interact with cigarette smoking and H.pylori infection to increase the risk of gastric cancer.