Manganese superoxide dismutase expression correlates with a poor prognosis in gastric cancer.

Objective: The biologic significance of superoxide dismutase (SOD) in transformed gastric carcinoma cells is unclear. The aim of this study was to examine the role of SOD as a prognostic indicator of gastric carcinomas and its association with other clinicopathological factors.

Methods: Expression of MnSOD and Cu/ZnSOD was evaluated immunohistochemically in gastric carcinomas and adenomas using tissue-array methods. The correlation between SOD immunoreactivity and clinical outcome or clinicopathological factors was investigated.

Results: MnSOD expression was associated with a poor patient prognosis and was strong in advanced gastric cancer, in the well-differentiated type and in the presence of lymphoid stroma (p < 0.05). On the other hand, there was no association between Cu/ZnSOD expression and patient survival. Cu/ZnSOD immunoreactivity was strong in advanced gastric cancer and in the presence of lymphoid stroma (p < 0.05) and was weak in signet ring cell type.

Conclusion: MnSOD immunoreactivity is significantly associated with poor outcome in gastric carcinoma patients although both MnSOD and Cu/ZnSOD have a connection with several clinicopathological parameters with some overlap.