[The activity of redox-regulatory systems in the tumor and its surrounding tissues in various histological types of tumor].

According to modern concepts cancer is a complex dynamic system having multiple relationships with both the immediate environment and with remote nonmalignant tissues and organs. Changes in the redox balance in them can result in disruption of the normal tissue control. Understanding of the biology of redox processes in a particular tumor and its surroundings, and of their functioning mechanisms is necessary for the development of new anti-cancer strategies based on the effects on the redox state of the tumor and surrounding tissue. Thus the aim of this work was to investigate activity of enzymatic systems influencing the redox state in the tumor tissue, peritumoral area and nonmalignant tissue (taken along the line of resection) for different histological types of tumors. The data obtained showed a similar level of reduced glutathione (GSH) in tumor tissues of gastric adenocarcinoma and vulvar squamous cell carcinoma, but its dynamics in the tissues surrounding the tumor was different. In contrast to the gastric adenocarcinoma the carcinoma of the vulva had a significant level of GSH and higher activity of glutathione dependent enzymes in the tumor tissue and its peritumoral area compared with the surrounding nonmalignant tissue. The results indicate that there are differences in the functioning of the redox regulatory systems in the tumor tissue and its surrounding tissues of various histological origin and localization, possibly due to different mechanisms involved in maintenance of the redox balance in the originally nonmalignant tissue.