About The Interconnection Between Erythropoietin, Mononuclears And Colon Carcinoma Cells

Background: Erythropoietin regulates erythropoiesis, express immune modulatory effects and it is suggested to be linked to tumorigenesis. We evaluated the effect of erythropoietin on the proliferation capacity of human peripheral blood mononuclear cells (PBMC) and colon carcinoma cells, detected its ability to induce production of inflammatory cytokines and assessed a possible impact on the cross-talk between immune and cancer cells. Methods: Non-stimulated human PBMC or cells stimulated with either mitogen or with HT-29 and RKO colon cancer cells were incubated for 24 hrs without or with various doses of erythropoietin and the concentration of TNFα, IL-1β, IL-6, IFNγ, IL-2, IL-10 and IL-1ra in the supernatants was detected. Results: EPO caused increased secretion of TNFα, IL-1β, IL- 6, IFNγ and IL-2 by RKO-stimulated PBMC, as well as IFNγ and IL-2 induced by PMA/ionomycin and TNFα production by non-stimulated or HT-29 stimulated PBMC. The production of anti-inflammatory cytokines was not affected by EPO. Conclusions: The enhancement of inflammatory cytokine secretion by PBMC incubated with colon cancer cells in the presence of erythropoietin indicates that the hormone is able to activate the immune cross-talk between these two types of cells. These findings enlighten the relationship between immune and colon cancer cells of certain lines. Keywords: Erythropoietin; Mononuclear Cells; Cytokines; Colon Cancer Cell