Influence Of Glutathione S-Transferase M1, T1 Null Genotype And Smoking And Alcohol Consumption On Susceptibility To Gastric Cancer In Zhuang Nationality Of Guangxi Province

Objective:To study the association of glutathione s-transferase M1 (GSTM1),glutathione s-transferase T1(GSTT1)null genotype,smoking and alcohol consumption with the risk of gastric cancer in Zhuang Nationality.Methods:A case-control study and polymerase chain reaction(PCR) technique were used to analyze the distribution frequencies of GSTM1 and GSTT1 null genotype among 70 cases of gastric cancer patients and 100 cases of controls.Unconditional logistic regression model and x~2 test were performed to evaluate the interaction of GSTM1,GSTT1 null genotype and smoking and alcohol consumption in the risk of gastric cancer.Results:1.The frequency of the GSTM1 null genotype was significantly increased in the cancer patients(55.7%;39/70)compared with the controls(39%; 39/100)(P=0.031).The frequency of the GSTT1 null genotype was significantly increased in the cancer patients(68.6%;48/70)compared with the controls(50%; 50/100)(P=0.016).2.GSTM1 null genotype,GSTT1 null genotype and smoking were the risk factors of gastric cancer by unconditional logistic regression model(OR=2.452, OR=2.321 and OR=2.088).3.No statistically significant differences were observed in the risk of gastric cancer in those with GSTM1(+),GSTT1(-)genotype or GSTM1(-),GSTT1(+) genotype when compared with those with GSTM1(+),GSTT1(+)genotype(OR =1.263,95%CI=0.516～3.091,P=0.609 and OR=1,95%CI=0.367～2.726, P=1.000).The risk of gastric cancer in those with GSTM1(-),GSTT1(-) genotype was significantly higher than that in those with GSTM1(+),GSTT1(+) genotype(OR=4.545,95%CI=1.747～11.827,P=0.001).4.No statistically significant difference was observed in the risk of gastric cancer in those with GSTM1(+)genotype and smoking when compared with those with GSTM1(+)genotype and non-smoking(OR=1.892,95%CI= 0.732～4.890,P=0.185).The risk of gastric cancer in those with GSTM1(-) genotype and non-smoking was significantly higher than that in those with GSTM1(+)genotype and non-smoking(OR=2.838,95%CI=1.260～6.394,P= 0.011).The risk of gastric cancer in those with GSTM1(-)genotype and smoking was significantly higher than that in those with GSTM1(+)genotype and non-smoking(OR=6.308,95%CI=2.287～17.398,P=0.000).5.No statistically significant differences were observed in the risk of gastric cancer in those with GSTM1(+)genotype,Alcohol consumption or GSTM1(-) genotype,Non-alcohol consumption when compared with those with GSTM1(+) genotype,Non-alcohol consumption(OR=1.186,95%CI=0.496～2.837,P= 0.702 and OR=1.639,95%CI=0.748～3.595,P=0.216).The risk of gastric cancer in those with GSTM1(-)genotype and alcohol consumption was significantly higher than that in those with GSTM1(+)genotype and non-alcohol consumption(OR=3.971,95%CI=1.412～11.165,P=0.007).6.No statistically significant differences were observed in the risk of gastric cancer in those with GSTT1(+)genotype,Smoking or GSTT1(-)genotype, Non-smoking when compared with those with GSTT1(+)genotype, Non-smoking(OR=1.089,95%CI=0.369～3.213,P=0.877 and OR=1.620, 95%CI=0.734～3.575,P=0.230).The risk of gastric cancer in those with GSTT1(-)genotype and smoking was significantly higher than that in those with GSTT1(+)genotype and non-smoking(OR=3.833,95%CI=1.561～9.414,P= 0.003).7.No statistically significant differences were observed in the risk of gastric cancer in those with GSTT1(+)genotype,Alcohol consumption or GSTT1(-) genotype,Non-alcohol consumption when compared with those with GSTT1(+) genotype,Non-alcohol consumption(OR=1.089,95%CI=0.369～3.213,P= 0.877 and OR=1.896,95%CI=0.855～4.202,P=0.113).The risk of gastric cancer in those with GSTT1(-)genotype and alcohol consumption was significantly higher than that in those with GSTT1(+)genotype and non-alcohol consumption(OR=2.852,95%CI=1.197～6.795,P=0.017).Conclusions:GSTM1 null genotype,GSTT1 null genotype and smoking were related to susceptibility to gastric cancer in Zhuang people in Guangxi. Furthermore,the interaction of GSTM1,GSTT1 null genotype and smoking and alcohol consumption existed in the risk of gastric cancer.