e17508 Background: Cervical cancer (CC) is one of the main causes of death among patients with gynecological tumors. As a rule, patients die from relapses and metastases which rates reach 30-45%. According to research data, treatment of patients with distant metastases is ineffective, and half of them die within 9.7 months, while the average survival is 15.9±0.26 months. The development of many pathological processes is considered to be associated with an increase in free-radical reactions leading to oxidative damage to various biomolecules. The purpose of the study was to analyze some characteristics of the free-radical oxidation and antioxidant defence in metastasizing CC. Methods: The study included 56 patients aged 29-73 years with stage IIB-IV CC after antitumor treatment. The main group – 27 patients who developed metastases within 4 months to 8 years after the CC diagnosis; controls – 29 patients with non-metastatic CC; donors – 19 healthy women aged 27-61 years. The accumulation of carbonyl derivatives in blood plasma proteins was detected in the reaction with 2, 4-dinitrophenylhydrazine. The induced oxidative modification of proteins was stimulated with Fenton's reagent. Free-radical processes was evaluated by the intensity of peroxide-induced luminol-dependent plasma chemiluminescence and the content of nitric oxide metabolites; the intensity of lipid peroxidation - by the content of malondialdehyde (MDA); the activity of catalase and ceruloplasmin was also studied. Results: CC progression was accompanied by increasing lipid peroxidation and spontaneous oxidation of blood plasma proteins. MDA levels in patients with metastases increased by 57.8% compared to donors and by 34.3% compared to patients without metastases (p < 0.05). The concentration of 2, 4-dinitrophenylhydrozones increased on average by 4 times compared to donors and by almost 2 times compared to patients without metastases. Patients with metastasizing CC demonstrated elevated levels of products of the interaction of nitric oxide and its derivatives with proteins and peptides - 3-nitrotyrosine and nitrosoglutathione, compared to both donors (by 31.4% and 55.3%) and patients in remission (by 38.1% and 34.5%). Chemiluminescence activity increased by 54.5% compared to donors (p < 0.05) and by 93% (p < 0.01) compared to controls. Catalase activity in the blood plasma of patients with metastases increased by 54.1% compared to donors, but was lower than the values in the control group (by 22.1%). Ceruloplasmin activity was increased only in patients without metastases (by 33%). Conclusions: The process of CC metastasis is accompanied by a greater intensity of oxidative processes of both proteins and lipids, as well as depletion of the adaptive capabilities of the body's antioxidant system.
Control of Electron Transfer in Nitric-oxide Synthases