Polymorphisms Of SOD1 And SOD2 And Risks Of Gastric Cancer

Objective:Superoxide dismutase (SOD) scavenges mainly reactive oxygen species (ROS) in vivo and plays a vital role in carcinogenesis. In this study, we investigated the association between gastric cancer and polymorphisms of SOD1 G2809A and SOD2 Val16Ala, and evaluate gene-gene and gene-environment interactions for gastric cancer development.Method:SOD1 and SOD2 polymorphisms were genotyped by Multiplex SNaPshot PCR in 145 GPL patients (containing 87 cases of gastric ulcer,33 cases of gastric polyps and 25 cases of atrophic gastritis),140 GC patients and 147 healthy controls. Immunoblotting analysis of H.Pylori antibody was used to detect H.Pylori infection and typing. Data was analyzed by chi-square test, One-Way ANOVA analysis and logistic regression analysis.Results:The SOD12809A/-genotype was associated with a higher risk of gastric cancer (OR,3.009; 95%CI,1.830～4.947; p=0.000) compared with G/G genotype. SOD2 16Ala/Val genotype was a risk factor for malignant potential of GPL (OR, 2.039; 95%CI,1.193～3.486; p=0.009). SOD2 16Ala/-genotype increased the risk of developing gastric cancer (OR,2.850; 95%CI,1.660-4.891; p=0.000). Multivariate logistic analysis showed that five factors were significantly associated with risk of gastric cancer, including SOD1 2809A/-genotype, SOD2 16Ala/-genotype, drinking, family history and type I H.Pylori infection, and there were additive interactions between the two genotypes and the other three risk factors. SOD2 Ala/Val genotype and positive family history were associated with malignant potential of GPL, and the combination of them was associated with a higher risk for the malignant potential of GPL (OR,7.706; 95%CI,2.104-28.219). Meanwhile, SOD1 2809A/-genotype and SOD2 16Ala/-genotype jointly contributed to higher risk for gastric cancer (OR, 6.426; 95%CI,3.198～12.913).Conclusion:SOD1 2809A/-genotype, SOD2 16Ala/-genotype, alcohol, positive family history and type I H.Pylori infection were associated with risk of gastric cancer in Han Chinese population, and there were positive gene-gene and gene-environment interactions for gastric cancer development. SOD2 Ala/-genotype and positive family history were risk factors for malignant potential of GPL, and there was super multiplication interaction.