Evaluation of Toll-like receptors expression in terms of colon cancer

Purpose of the study. To evaluate the number of cells with the CD45+/- phenotype expressing Toll-like receptors (TLRs) in tissues of the tumor, peritumoral area and resection line tissues in colon cancer (CC) with various tumor locations.Materials and methods. The study included 50 patients with CC. All patients underwent surgery as the primary treatment, and tissue material was collected from the patients. Expression of TLRs (2, 3, 4, 8, 9) on CD45+, CD45- cell populations was determined by flow cytometry in cell suspensions obtained from tissues of the tumor, peritumoral area (1–3 cm from the tumor) and resection line tissues (~10 cm from the tumor) with further calculation of the percentage of cells with the corresponding phenotype from the total number of cells.Results. An analysis of left-sided colon tumors showed lower percentage of CD45- cells expressing TLR4, 8, compared to rightsided tumors, by 38 % and 25 %. A comparative analysis of the number of CD45+ cells expressing TLR 2, 4 showed their decrease by 81 % and 87 %, respectively, compared with right-sided tumors. An assessment of the data in the perifocal zone of left-sided colon tumors, compared with right-sided ones, demonstrated a decrease in the percentage of cells with the CD45- phenotype that express TLR4, by 61 %. Resection line tissues in left-sided tumors, compared with right-sided ones, showed a statistically significant increase in the percentage of CD45- cells that express TLR 2, 4 by 205 % and 55 %, respectively. The number of CD45+ cells expressing TLR 4 decreased by 87 %. An assessment of the number of cells expressing TLRs 3 and 9 in the tumor, peritumoral area and resection line tissues did not reveal significant differences.Conclusions. Lower number of cells with CD45+ and CD45- phenotypes express TLRs 2, 4, 8 in left-sided colon tumors and their peritumoral tissues, compared to right-sided cancer.