Differences in cell cycle kinetics during induced granulocytic versus monocytic maturation of HL-60 leukemia cells.

Leukemia cells (HL-60) were induced to mature towards granulocytic and monocytic phenotypes using 1.1% dimethyl sulfoxide and 5 X 10(-7) M 1-beta-D-arabinofuranosylcytosine, respectively. Granulocytic maturation was accompanied by a slight decrease in cell volume and in total cell protein, but with an increase in acid phosphatase. DNA histograms showed that after 7 days there was a decrease in the number of cells with S or G2 DNA content. Autoradiography revealed that most of the cells had stopped in cycle with only 3% of the cells synthesizing DNA. The rate of synthesis for these few cells, morphologically identified as immature blast forms, was not diminished. Monocytic maturation was accompanied by an increase in cell volume and of alpha-naphthyl acetate esterase. DNA histograms showed no change over 7 days. Autoradiography revealed a large fraction of the cells to be in cycle and synthesizing DNA, but at a markedly reduced rate. Induced granulocytic and monocytic maturation are characterized by a very different perturbation of the cell DNA-division cycle.