The Study Of The Relationship Of HOGGl Gene Polymorphisms And Susceptibility To Gastrointestinal Cancer

Objective:To examine the assiociations between human8-oxoguanine DNA glycosylase1(hOGG1) genepolymorphisms and genetic susceptibility of gastric cancer, liver cancer, colorectal cancer. And investagedthe interaction of smoking, drinking and gene polymorphisms, which whether could be increased the risk ofgastric cancer, liver cancer and colorectal cancer risk.Methods: This study was carried out in Zhengzhou and Kaifeng city of Henan, China. included a total of98gastric cancers,76liver cancer patients,95colorectal cancer patients and80controls. One milliliterperipheral venous blood was drawn from the study subjects. hOGG1Ser326Cys polymorphism wasgenotyped by a real time polymeras chain reaction-TaqMan. then investigate its relationship betweengastric cancer，liver cancer, colorectal cancer and the exon7of the1245bp C/G of hOGG1genepolymorphisms. Students，s t-test was used to compare mean value of the samples. While categorical datawere analyzed by the chi square test and unconditional logistic regression models.The odds ratio (OR) and95%confidence interval (CI) were used to indicate relative risk of gastric cancer, liver cancer, colorectalcancer. The statistical tests were two-sided probability test, P<0.05indicates statistically significantdifference.Results: All case patients and control subjects were adequately matehed by age (P=0.145, P=0.140,P=0.126), sex (P=0.861, P=0.103, P=0.052). The gene balance test of control group showed no statisticallysignificant (χ2=4.789, P=0.091), the selected control group of this study was representative.The genotype frequencies of Cys326Cys respectively in the group of gastric cancers were26.53%,liver cancers were28.95%and colorectal cancers were27.37%, Which were singnificantly higherthan11.25%of contronls(P=0.023, P=0.021, P=0.010). Compared to Ser326Ser genotype who carried incontrols, Cys326Cys genotype tooked in cases respectively increased the risk of gastric cancer1.7times(P=0.002), liver cancer1.8times (P=0.000) and colorectal cancer1.9times (P=0.016).When326Cys allele and smoking were exited at the same time, there were not interactions in thesethree cancers (S≈1). When326Cys allele and drinking were exited at the same time, increased the risk ofgastric cancer1.70times, and38%of the gastric cancer population s was caused due to the interaction ofthe two factors(RERI=1.70, S=1.97, API=0.38, P=0.008). and increased the risk of liver cancer1.45times, 30%of the liver cancer populations was caused due to the interaction of the two factors(RERI=1.45,S=1.60, API=0.30, P=0.036).but had not correlation with the incidence of colorectal cancer (S≈1).Conclusion: The Cys326Cys genotype of hOGG1Ser326Cys gene may be related to the susceptibility ofthe three cancers.326Cys allele with smoking who tooked, there was no interaction in these three cancers.When326Cys allele and drinking were exited at the same time, increased the risk of gastric cancer andliver cancer, but there was no interaction in colorectal cancer.