The effects of phorbol myristate acetate (PMA) on in vitro hematologic cell differentiation were investigated to evaluate the values in the diagnosis of subtypes of hematologic malignancies. The cells of 18 different type of leukemia/lymphoma cell lines and other 18 fresh samples from patients with leukemia or lymphoma were used in this study. Dosage of PMA was 5 ng/ml and cultures were continued for 72 hours. The induction of differentiation to macrophage-like cells of various degree was observed in 2 of 5 patients with unclassified leukemia. Weak changes were observed in 2 of 2 common type cultured cell lines and cells from 3 of 5 patients with common ALL. No change was observed in 11 T- and B-cell type cultured cells and cells from 3 patients with T- and B-cell type malignancies. Marked changes were noted in 4 of 5 myelomonocytoid type cultured cell lines and cells of all 5 patients with meylo-monocytoid leukemia.
Most of cells with morphological changes were α-NBE positive with incomplete NaF inhibition, but none of them became positive for POX staining.
Thus, in vitro treatment with PMA appeared to induce differentiations of leukemia and lymphoma cells corresponding to their lineages and maturation stage; diagnostic values of this measure was suggested.
