EMF induces differentiation in HL-60 cells

This investigation provides evidence that a 60-Hz electromagnetic field (EM F) at 1 gauss (G) can drive differentiation of cultured hematopoietic proge nitor cells. HL-60 cells are known to differentiate from a nonphagocytic su spension culture to an attached fibroblast-like culture with high phagocyti c activity in the presence of the tumor-promoting phorbol eater 12-0-retrad ecanoylphorbal-13-acetate (TPA). The effect of 60-Hz EMF all G on different iation is approximately equivalent to treatment of the cells with 250-500 p g/ml TPA. Furthermore, the effect, of both EMF and TPA treatment on differe ntiation is additive at low TPA concentrations. The results strongly sugges t similarities between the effects of TPA treatment and EMF exposure and th us provide an approach for tracing the origins of the molecular effects of EMF exposure, as many transduction pathways in the differentiative process are defined, (C) 1999 Wiley-Liss, Inc.