title: Granulocyte colony-stimulating factor-induced activation of protein kinase-C in myeloid cells.
abstract: Granulocyte colony stimulating factor (G-CSF) regulates survival, proliferation, differentiation, and activation of myeloid cells. It binds to a high affinity receptor (G-CSF-R) expressed on myeloid cells, for which the signal transduction mechanisms other than protein tyrosine kinase (PTK) activation have not been completely identified. We explored the potential involvement of protein kinase-C (PKC) in G-CSF-R signal transduction. In this report, we provide direct evidence of PKC activation by G-CSF-R. G-CSF treatment of peripheral blood neutrophils, granulocytic cell lines (HL-60, NFS-60, KG-1), and monocytic cell lines (WEHI-3B,U-937) resulted in PKC activation. Chelerythrine chloride and HA-100, an isoquinolinesulfonamide derivative, the specific inhibitors of PKC, 1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid (BAPTA), a chelator of intracellular calcium, and 3,4,5-trimethoxybenzoic acid 8-(diethylamino)-octyl ester (TMB-8), an inhibitor of intracellular calcium release, blocked G-CSF-induced PKC activation in HL-60 cells, and reduced CD11b upregulation in neutrophils, but did not affect ligand-binding or down-modulation of G-CSF-R. Methyl 2,5-dihydroxycinnamate (MDHC), a potent inhibitor of protein tyrosine kinases (PTK), also inhibited PKC activation in response to G-CSF treatment, suggesting that PKC activation may occur downstream of PTK activation. Our results demonstrate the involvement of PKC in G-CSF-R signal transduction, and suggest a common signaling pathway in myeloid cells of granulocytic and monocytic lineages.
authors.affiliation: James Ewing Laboratory of Developmental Hematopoiesis, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
authors.forename: R V
authors.initials: RV
authors.lastname: Deshpande
authors.forename: R H
authors.initials: RH
authors.lastname: Peterson
authors.forename: M A
authors.initials: MA
authors.lastname: Moore
mesh_terms: D000470:Alkaloids; D000818:Animals; D053119:Benzophenanthridines; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005707:Gallic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D016179:Granulocyte Colony-Stimulating Factor / Q000187:drug effects / Q000378:metabolism / Q000494:pharmacology*; D018922:HL-60 Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007457:Iodine Radioisotopes; D007951:Leukemia, Myeloid / Q000188:drug therapy / Q000378:metabolism*; D016177:Macrophage-1 Antigen / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism; D010617:Phenanthridines / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000378:metabolism*; D015398:Signal Transduction; D013936:Thymidine / Q000378:metabolism / Q000493:pharmacokinetics; D014316:Tritium; D014407:Tumor Cells, Cultured
chemical_list: D000470:Alkaloids; D053119:Benzophenanthridines; D004791:Enzyme Inhibitors; D007457:Iodine Radioisotopes; D016177:Macrophage-1 Antigen; D010617:Phenanthridines; D014316:Tritium; D016179:Granulocyte Colony-Stimulating Factor; D004533:Egtazic Acid; C006014:8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate; D005707:Gallic Acid; C016299:chelerythrine; D011493:Protein Kinase C; C025603:1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid; D013936:Thymidine