Erythropoietin-dependent autocrine secretion of tumor necrosis factor-alpha in hematopoietic cells modulates proliferation via MAP kinase--ERK-1/2 and does not require tyrosine docking sites in the EPO receptor.
Chen J, Jacobs-Helber SM, Barber DL, Sawyer ST, Exp Cell Res, 2004 Aug 1 - link