Evaluation of oxidative stress and antioxidant levels in cats with mammary tumors of different histopathological grades

In this study, the relationship of tumor microenvironment with oxidative stress and antioxidant response were investigated in the tumor tissue of 17 cats with malignant mammary tumors. For this purpose, CD3, nuclear factor kappa beta (NF-Kß), CD31, vascular endothelial growth factor (VEGF), inducible nitric oxide synthase (iNOS), hypoxia-inducible factor 1 alpha (HIF-1α), tumor necrotic factor alpha (TNF-α) and 8 hydroxyguanosine (8OHdG) antibodies was evaluated by immunohistochemical method, and total antioxidant status (TAS), total oxidative stress index (OSI), oxidative stress index (TOS), reduced glutathione (GSH), melondialdehyde (MDA), nitric oxide (NO) and catalase (CAT) analyses were performed biochemically from blood serum. In immunohistochemical analyses, all antibodies were stained more intensively in grade 3 tumors. The relationships of these antibodies to each other were clearly revealed in grade 3 tumors. There was no difference in the staining intensity of antibodies between grade 1 and 2 tumors. In terms of antibodies other than CD31, the staining intensity different between grade 3 and 1 tumors. CD31, on the other hand, was painted almost equally in all sections. In biochemical analyzes, there was no difference between the control group and tumor groups in oxidative stress markers only in NO value, but there was a difference between the groups in TOS, OSI and MDA values. In MDA analysis, there was a significant difference between the control group and grade 3 tumors. Among antioxidants, a difference was found between the control group and grade 3 tumors in total antioxidant capacity, and between the control group and grade 1 tumors in CAT analysis. There was no difference between the groups in GSH analysis. In chemical analysis, it was found that the parameters did not show significant variability between grades. The study is important in terms of the effect of oxidative stress on the tumor and tumor microenvironment, and the evaluation of interrelated parameters in the tumor and tumor microenvironment. It was determined that the evaluated parameters were more intensely stained in more malignant tumors. This study is one of the most comprehensive studies on feline mammary tumor and tumor microenvironment. Although increased parameters evaluated are associated with poor prognosis, these parameters have not yet been fully integrated into the disease in feline mammary tumors. Larger sample sizes should be studied in terms of affecting the prognosis and treatment options of the disease, and all of these patients should be followed up after the operation.