Study On The Relationship Among Polymorphisms In COX-2, PARP-1 And Gastric Cancer In High And Low Incidence Areas

Objective 1.To investigate Distribution Features of single nucleotide polymorphisms(SNPs) in the promoter region of the -765G＞C COX-2 and PARP-1 Va1762Ala genes including gastric groups,gastric precancerous lesions and controls in Han Chinese population in high and low incidence areas of Gansu province.2.To analyze the polymorphism of the -765G＞C COX-2 and PARP-1 Va1762Ala genes and the relations their genotypes with the risk of gastric cancer in high and low incidence areas of Gansu province.3.By compare with distribution of frequency of every genotypes in gastric groups and gastric precancerous lesions to define genotypes which increase the risk of gastric cancer..Methods 1.Subjects were divided into three groups.142 patients with gastric cancer(including High-incidence area 98,Low 44),128 gastric precancerous lesion patients(including High-incidence area 88,Low 40) and 110 controls (including High-incidence area 90,Low 60) were enrolled.all come from Gansu province.The first two groups were recruited by pathological diagnosis.2.To detect the polymorphisms using a polymerase chain reaction-restriction fragment length poltmorphism(PCR-RFLP).method.3.ELISA kits detect Infection rates of Helicobacter pylori.4.The results were analyzed by SPSS 13.0.Results 1.General characteristics of the study:Distribution of frequency in gastric groups which HP Ig G and family history positions were Higher than Controls in high- incidence areas.2.COX-2-765G＞C GC genotype were all singnificantly in the gastric cancer cases(18.4%,13.6%) compared with Gastric precancerous lesions(6.8%,7.5%)and controls(7.7%,6.7%) in High and low incidence areas. Compared with gastric low-incidence areas GC genotype carriers have Significant difference with the risk of gastric cancer in High-incidence areas(OR₁,2.705;95%Cl, 1.070-6.836;P=0.031).Combined GC genotype with CC genotype and compared to GG genotype,had singnificant risk in gastrc cancer groups(OR,2.455;95%Cl, 1.059-5.691;P=0.033).It illustrated C carriers have Significant risk in gastric cancer cases by contrast with low-incidence areas.3.PARP-1Va1762Ala CC genotype in the gastric cancer groups(12.2%) was higher than Gastric precancerous lesions(6.8%) and controls(3.4%),Different from low-incidence areas,CC carriers have statistics difference with the risk of gastric cancer in High-incidence areas(OR₁,24.407;95%Cl,1.185-16.387;P= 0.018).Combined TC genotype with CC genotype and compared to TT genotype had no Significant difference(P₂＞0.05).4.Among H.pylori IgG positive subjects,COX-2 -765 GC genotype carrier's risk for gastric cancer is 3.685-fold(OR,3.685:95%Cl 1.004-13.529; P=0.039) han GG carrier's in High-incidence areas,PARP-1 762 C genotype carriers and T genotype carriers had no statistics difference.Conclusion 1.COX-2 promoter region -765G＞C GC genotype is associated to elevated risk of gastric cancer in Han Chinese population in High- incidence areas of Gansu province and C carriers have significant elevated risk of gastric cancer.This illustrate c allele gene play a important role in Susceptibility to gastric cancer in in high-incidence areas in Gansu province.2.PARP-1 Va1762Ala CC genotype is associated to elevated risk of gastric cancer in Han Chinese population in Highincidence areas of Gansu province.3.Among H.pylori IgG positive subjects,COX-2 -765G＞C GC genotype Carriers have the significantly increased risk of gastric cancer. 4.Whether in high-incidence areas or low-incidence areas,COX-2-765G＞C4å’ŒPARP-2 Va1762Ala every genotypes have no possible to actuate gastric precancerous lesion develop into gastric cancer.