“…K562 cells can undergo further differentiation in both megakaryocytic and erythroid lineages depending on the stimulus. Phorbol esters such as PMA-stimulated megakaryocytic differentiation (Shelly et al, 1998;Kim et al, 2001;Dorsey et al, 2002;Pettiford and Herbst, 2003), whereas hemin, hydroxyurea, Ara-C or as reported more recently imatinib mesylate (gleevec) induced erythroid differentiation of this cell line (Belhacene et al, 1998;Park et al, 2001;Jacquel et al, 2003;Kawano et al, 2004a, b). Megakaryocytic differentiation of K562 cells induced by PMA mimics, in part, the physiologic process that takes place in the bone marrow in response to a variety of stimuli (Long et al, 1990).…”