Oxidative Stress and Redox-Dependent Signaling in Prostate Cancer.

Tumor emergence and progression is complicated by the dual role of reactive oxygen species (ROS). Low concentrations of ROS are essential for many intracellular metabolic processes and cell proliferation, while excessive ROS generation disrupts the mechanisms of cancer suppression, leading to the cell damage and death. A long-term imbalance in the ROS/antioxidant ratio and upregulation of the ROS generation due to the reduced efficacy of the antioxidant defense system cause chronic oxidative stress resulting in the damage of proteins, lipid, and DNA molecules and cancer development.

Glutathione Synthesis in Cancer Cells.

Tripeptide GSH is associated not only with the control and maintenance of redox cell homeostasis, but also with the processes of detoxification, proliferation, cell differentiation, and regulation of cell death. Disruptions in GSH synthesis and changes in the GSH/GSSG ratio are common for many pathological conditions, including malignant neoplasms. Numerous data indicate the importance of GSH and the GSH/GSSG ratio in the regulation of tumor cell viability, in the initiation of tumor development, progression, and drug resistance.

[Glutathione-dependent enzymes and glucose-6-phosphate dehydrogenase of blood in patients with lymphosarcoma (non-Hodgkin's disease)].

Activities of glutathione-dependent enzymes and glucose-6-phosphate dehydrogenase (GPDH) were studied in blood of the patients with lymphosarcoma (LS). The activity of glutathione reductase (GR), glutathione dehydroascorbate reductase (GDAR), gamma-glutamyltranspeptidase (GGT) and G6PDH in plasma, leucocytes, lymphocytes and erythrocytes of peripheral blood in 30 patients (42-56 years) with LS and in 20 healthy have been determined with spectrophotometric methods (Humalyzer 2000 DE). Leucocytes and lymphocytes were separated from blood using Boyum method.

[Glutathione-dependent enzymes and glucose-6-phosphate dehydrogenase in breast tumors].

The authors made a comparative analysis of the activity of antioxidative enzymes and a search for a possible relationship between the activity of glutathione reductase and that of glucose-6-phosphate dehydrogenase in the blood and saliva of patients with breast tumors with varying activity of the pathological process.

[Impact of antioxidative therapy on state of enzymic redox-system of glutathione in patients with phlegmons of maxillofacial area].

Traditional and antioxidative therapy (retinol and alpha-tocopherol) was done by therapeutic course to 18 patients with phlegmons of maxillofacial region. In the peripheral blood leucocytes and tissues (skin, muscle) of the patients with phlegmons there were determined glutathione reductase activity, glutathione peroxidase activity and content of glutathione. Disbalance of glutathione enzyme redox system in leucocytes of patients with phlegmons was corrected by comprehensive therapy after 1 week.