Investigation of the level of TERT gene expression in the colon mucosa in various pathologies

Introduction. According to the statistics of malignant neoplasms in Russia, colorectal cancer is the second leading cause of death from cancer in both sexes. The disease progresses as a multi-stage process and is associated with genetic changes. One of the characteristic features of cancer is a change in the activity of telomerase reverse transcriptase (TERT), more often its activation. This study compared the expression of the TERT gene in adenocarcinoma, adenoma, and morphologically unchanged tissues (MUT) in different parts of the colon and rectum.Objective: to conduct a comparative analysis of changes in the expression of the proliferation marker TERT in benign and malignant neoplasms of the colon, using TERT expression in the unchanged colon mucosa of healthy donors as reference values.Materials and methods. The RT-PCR method was used to analyze changes in the TERT expression in the colon. The analysis included tissue samples of colon adenocarcinoma (n=193), MUT of the resection edge (about 15 - 20 cm from the tumor node) (n=230), adenoma (n=21), unchanged colon mucosa in adenoma (10 - 15 cm from the adenoma) (n=58), and visually unchanged mucosa of healthy donors (n=174). Adenocarcinoma and MUT tissues of the resection edge were obtained during surgical treatment. Adenoma tissues, MUT for adenoma and unchanged tissues from healthy donors were obtained during preventive colonoscopy.Results. The level of TERT expression in the colon tissues of healthy donors was significantly higher than in unchanged colon tissues in benign and malignant proliferative diseases. According to literature data, in studies using unchanged tissue of the affected organ as the “norm”, the level of TERT expression was lower than in the tumor tissue. This highlights the importance of using morphologically unchanged tissues from healthy donors as controls.