Hemin does not cause commitment of murine erythroleukemia (MEL) cells to terminal differentiation

The effect of hemin on the differentiation program of murine erythroleukemia (MEL) cells has been investigated. While hemin treatment does induce increased levels of globin mRNA and hemoglobin, it fails to lead to other biochemical changes associated with MEL cell differentiation induced by DMSO and thioguanine. These include increased levels of the nuclear protein IP25 and of the enzyme cytidine deaminase. Clonal analysis of hemin-treated cells revealed that unlike other inducers, hemin does not cause a reprogramming of MEL cells to a specific limitation of proliferative capacity. These observations suggest that hemin differs from DMSO and thioguanine in that it exerts specific effects on globin expression in MEL cells without triggering commitment to the terminal differentiation program.