Introduction/Background Animportant role of neutrophils in antitumor immunity does not cause doubt. Assessment of the functional status determined by the state of cell metabolism is considered one of methods to control immune homeostasis. Our purpose was to study the antioxidant defense in tumor-infiltrating neutrophils and blood neutrophils of patients with ovarian cancer (OC).

Methodology Levels of A and E vitamins and activity of catalase, SOD and glutathione peroxidase (GP) were determined by ELISA in neutrophils isolated from malignant ovarian tissues and blood of 45 patients with OC T_3-4N_xMx. Intact ovaries and blood of healthy donors were used as a control.

Results The amount of neutrophils in tumors was 2.9 times higher than in intact ovaries, while protein amount in them was 2.9 times lower. E and A vitamins in tumor neutrophils were decreased by 2.5 and 1.9 times compared to control values, and their ratio did not change. SOD and GP activity did not differ significantly from the values in intact tissues, but their ratio was 12.5 times lower. Catalase activity in neutrophils of tumor and intact tissues was similar.

The amount of neutrophils in the blood of patients was 1.5 times higher than in healthy donors, while protein content in the cells did not differ significantly. Levels of E and A vitamins and their ratio in blood neutrophils of OC patients were 8.3, 4.7 and 1.8 times lower, respectively, than in healthy people. Activity of SOD and GP was similar to the control values, but their ratio was 2 times lower than in donors. Catalase activity in patients was 2.5 times lower.

Conclusion Tumor-infiltrating neutrophils had abnormalities in both units of the antioxidant defense which may cause a decrease in their functional activity impeding an adequate antitumor response, but their normal ability to chemotaxis was maintained.

Disclosure Nothing to disclose.