VEGF-and EGF-mediated cooperation of eosinophilic granulocytes and tumor cells in gastric and colon cancer

Aim of the research – to analyze secretion of vascular endothelial growth factor (VEGF) and epidermal growth factor (EGF) by blood eosinophilic granulocytes in vitro, together with an expression of VEGFR and EGFR in tumor tissue in gastric and colon cancer in association with tissue eosinophilia.Materials and methods. A total of 52 patients with gastric cancer and 50 patients with colon cancer were examined. The material of the research included supernatants of eosinophil cultures and samples of malignant tumors tissues of the stomach and colon. Enzyme-linked immunosorbent assay was used to determine the contents of VEGF and EGF in the eosinophil culture supernatants in vitro. The expression of VEGFR and EGFR in tumor tissue was evaluated by immunohistochemistry. The results were analyzed by statistical methods.Results. An increase in basal and r-IL-5-induced secretion of VEGF by eosinophilic granulocytes of blood in vitro was found in patients with gastric cancer accompanied by tissue eosinophilia. The concentration of EGF in the culture of blood eosinophils in vitro with the addition of r-IL-5 increased in patients with eosinophilic infiltration of tumor tissue, regardless of the localization of the pathological process,both in patients with gastric cancer and colon cancer. Eosinophilic infiltration of the tumor tissue in gastric cancer and colon cancer was combined with hypo-expression of EGFR by tumor cells; VEGFR receptor expression was not dependent on the presence of eosinophilic granulocytes in the tissue of tumors.Conclusion. Hypersecretion of vascular endothelial growth factor VEGF and epidermal growth factor EGF (upon stimulation with r-IL-5) by blood eosinophils in vitro in patients with gastric and colon cancer with tissue eosinophilia indicates an increase in the activity of these cells. Deficiency of expression of VEGF and EGFR receptors in tumor tissue causes violation of cooperative interaction of eosinophilic granulocytes and tumor cells in malignant tumors of the stomach and large intestine