ІМУНОГІСТОХІМІЧНА ОЦІНКА ПОТЕНЦІАЛУ МОЛЕКУЛЯРНОГО ВОДНЮ ПРИ КОЛОРЕКТАЛЬНОМУ РАКУ

Colorectal cancer (CRC) is one of the leading causes of cancer-related mortality. Currently, new strategies to improve the quality of life for CRC patients are being actively explored. Molecular hydrogen has garnered attention as a biologically active molecule capable of reducing oxidative stress, modulating signaling pathways related to inflammation, proliferation, and immune cell activity, and influencing the tumor microenvironment. Aim. To investigate, using immunohistochemical studies on a rat CRC model, how water enriched with molecular hydrogen affects markers of immune cells, inflammation, proliferation, and the cell cycle. Material and Methods. Animals were divided into three groups: Group 1 – control; Group 2 – rats with CRC induced by 1,2-DMH administration for 30 weeks and given access to regular water; Group 3 – rats with induced CRC that consumed water enriched with molecular hydrogen at a concentration of 0.6 ppm. For immunohistochemical detection of target molecules in the intestinal wall, antibodies against CD4+, CD8+, CD20+, CD68+ cells, TNF-α, Ki-67, and p53 were used. Results. In the colon wall of rats with CRC, the percentage of T-helper cells (CD4+) exceeded the intact value by 11.02 times, T-killer cells (CD8+) by 3.33 times, B-lymphocytes (CD20+) by 11.41 times, and the macrophage population (CD68+) in aberrant foci increased by 11.28 times, while TNF-α expression rose by 16.72 times (p<0.001 in all cases). Under carcinogenesis conditions, the index of proliferative activity (Ki-67 exceeded the norm by 2.38 times (p<0.001)) and the intensity of the cell cycle (p53 levels were 6.85 times higher than the intact value (p<0.001)) also increased. In CRC rats consuming molecular hydrogen-enriched water, compared to uncorrected rats, a slight decrease in CD4+ and CD20+ cells and a minor increase in CD8+ cells were observed in the colon wall. The average expression levels of CD68 and TNF-α in Group 3 were significantly lower than in Group 2 by 1.33 and 1.22 times, respectively. However, no statistically significant differences in Ki-67 and p53 expression in the colon wall were found between Groups 2 and 3. Conclusion. Molecular hydrogen promotes adaptive antitumor immunity, enhances the activity of cytotoxic CD8+ cells capable of destroying tumor cells, effectively reduces inflammation (CD68+, TNF-α), but does not affect proliferation (Ki-67) or p53 accumulation. This suggests its auxiliary role in modulating the microenvironment rather than influencing core oncogenic processes in the rat CRC model.