Marked apoptosis of human myelomonocytic leukemia cell line P39 : significance of cellular differentiation

Myelodysplastic syndrome (MDS)-derived leukemia cell line P39/Tsugane could be induced to apoptosis by a variety of agents including metabolic inhibitors, a calcium ionophore and differentiation-inducing agents. As evaluated by characteristic morphological changes and oligonucleosomal lengths DNA ladder, the levels of apoptosis in P39 cells induced by actinomycin D, or A23187, were far greater than in other myeloid lines examined in this study. When 22-oxa-1α,25(OH) 2 D 3 (D 3 ), dimethyl sulfoxide (DMSO) and all-trans retinoic acid (RA) were used as differentiation-inducers, varying degrees of apoptosis were seen. D 3 induced monocytoid differentiation, but not apoptosis above the control level