title: Tumor-promoting phorbol esters stimulate the proliferation of interleukin-3 dependent cells.
abstract: To determine whether activation of protein kinase C is involved in the proliferation of interleukin-3 (IL-3) -dependent cells, we examined the effect of tumor-promoting phorbol esters on the in vitro proliferation of the IL-3-dependent cell lines FD and DA-1. The viability of FD and DA-1 cells cultured for 24 hours in 100 nM phorbol myristate acetate (PMA) and 10% FCS was similar to that of cells cultured in 25% WEHI-3 conditioned medium as a source of IL-3, and 10% FCS. FD cells failed to proliferate in concentrations of FCS of up to 50%, while DA-1 cell proliferation was not markedly influenced by FCS. By contrast, PMA promoted the proliferation of FD and DA-1 cells in the absence of FCS and enhanced their proliferation in the presence of 10% FCS, 60- and 20-fold, respectively. Stimulation of proliferation was achieved with as little as 10 nM PMA and was maximal at 100 nM PMA. Low concentrations (0.05-0.1%) of WEHI-3 CM promoted the proliferative response of FD and DA-1 cells to PMA, but at concentrations of WEHI-3 CM greater than 0.8%, no further increment in proliferation was obtained with PMA. As little as 1/2 hour of exposure to phorbol esters was sufficient to cause translocation of protein kinase C from the cytosol to the membranes of DA-1 cells, and 1 hour of exposure to phorbol esters was sufficient to stimulate DNA synthesis. A protein kinase C inhibitor, H-7, at a concentration of 10 microM inhibited phorbol ester-induced stimulation of DA-1 cell proliferation. When DA-1 cells were exposed to the calcium ionophore A23187 in addition to both a phorbol ester and IL-3, their proliferation was enhanced over that stimulated by only the phorbol ester and IL-3. The data indicate that stimulation of proliferation of IL-3-dependent cells involves the activation of protein kinase C.
mesh_terms: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival; D003115:Colony-Stimulating Factors / Q000494:pharmacology; D004789:Enzyme Activation; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D006133:Growth Substances / Q000494:pharmacology; D007377:Interleukin-3 / Q000494:pharmacology*; D007546:Isoquinolines / Q000494:pharmacology; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D010703:Phorbol Esters / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D003115:Colony-Stimulating Factors; D006133:Growth Substances; D007377:Interleukin-3; D007546:Isoquinolines; D010703:Phorbol Esters; D010879:Piperazines; D015240:Phorbol 12,13-Dibutyrate; D000001:Calcimycin; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate