INDUCTION OF DIFFERENTIATION OF HL-60 CELLS BY DIMETHYLSULFOXIDE - EVIDENCE FOR A STOCHASTIC-MODEL NOT LINKED TO THE CELL-DIVISION CYCLE

  • 1 January 1982
    • journal article
    • research article
    • Vol. 42  (2) , 445-449
Abstract
Induction of differentiation of the human promyelocytic leukemia cell line HL-60 by dimethyl sulfoxide [DMSO] was analyzed to determine the relationship between exposure time of the inducer and cell cycle. A minimum incubation time of 12 h with DMSO was required in order to induce differentiation in a small but significant proportion of cells. These expressed differentiation markers (morphology, phagocytosis, and nitroblue tetrazolium reduction) up to 12 h after DMSO was removed from the medium. For periods beyond 12 h and as long as 120 h of contact of HL-60 cells with the inducing agent, a linear rise in the percentage of differentiated cells was observed. The sensitivity to DMSO of HL-60 cells synchronized by double thymidine block was examined and was similar to that of nonsynchronized cells. The effect of DMSO was not altered when incubated with cells at different phases of the cell cycle. Even nonproliferating cells were sensitive to the inducing effect of DMSO. The data are consistent with a stochastic model of induction to differentiation without having any linkage to the cell cycle.