title: The role of STAT3 in granulocyte colony-stimulating factor-induced enhancement of neutrophilic differentiation of Me2SO-treated HL-60 cells. GM-CSF inhibits the nuclear translocation of tyrosine-phosphorylated STAT3.
abstract: The role of granulocyte colony-stimulating factor (G-CSF) on neutrophilic differentiation of Me2SO-treated HL-60 cells was studied. G-CSF augmented the functional maturation of Me2SO-treated HL-60 cells in terms of both O-2-generating ability and expression of the formyl-methionyl-leucyl-phenylalanine receptor. G-CSF induced enhancement of cell growth in Me2SO-treated HL-60 cells. These results indicate that G-CSF is a potent enhancer for the differentiation and proliferation of Me2SO-treated HL-60 cells. G-CSF caused the activation of p70 S6 kinase but not mitogen-activated protein (MAP) kinase. On the other hand, G-CSF rapidly induced tyrosine phosphorylation of signal transducers and activators of transcription-3 (STAT3), but did not induce serine727 phosphorylation. From the analysis of confocal laser scanning fluorescence microscopy and differential centrifugation, it was clearly demonstrated that G-CSF induced nuclear translocation of tyrosine-phosphorylated STAT3. The G-CSF-dependent enhancement of neutrophilic differentiation in Me2SO-HL-60 cells was reversely inhibited by granulocyte-macrophage colony-stimulating factor (GM-CSF). Notably, in the presence of GM-CSF, G-CSF induced the tyrosine phosphorylation of STAT3 but failed to induce the nuclear translocation of tyrosine-phosphorylated STAT3. GM-CSF induced activation of not only p70 S6 kinase, but also of MAP kinase. Furthermore, GM-CSF caused the rapid serine727 phosphorylation of STAT3, both in the presence and absence of G-CSF. PD98059, an MEK1 inhibitor, inhibited the G-CSF-dependent serine727 phosphorylation of STAT3 and blocked the inhibitory effect of GM-CSF on G-CSF-dependent nuclear translocation of STAT3. These results suggest that G-CSF-dependent nuclear translocation of STAT3 coordinates with the promotion of neutrophilic differentiation in Me2SO-treated HL-60 cells.
authors.affiliation: Department of Biological Chemistry and Biologicals, National Institute of Health Sciences, Kamiyoga 1-18-1, Setagaya-ku, Tokyo 158-8501, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: T
authors.initials: T
authors.lastname: Mukasa
authors.forename: E
authors.initials: E
authors.lastname: Uchida
authors.forename: T
authors.initials: T
authors.lastname: Kanayasu-Toyoda
authors.forename: T
authors.initials: T
authors.lastname: Hayakawa
mesh_terms: D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004121:Dimethyl Sulfoxide; D004789:Enzyme Activation / Q000187:drug effects; D005419:Flavonoids / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D018922:HL-60 Cells / Q000187:drug effects*; D006801:Humans; D019000:Phosphotyrosine / Q000032:analysis; D019893:Ribosomal Protein S6 Kinases / Q000378:metabolism; D050796:STAT3 Transcription Factor; D015398:Signal Transduction / Q000187:drug effects; D015534:Trans-Activators / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; D005419:Flavonoids; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D015534:Trans-Activators; D016179:Granulocyte Colony-Stimulating Factor; D019000:Phosphotyrosine; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D019893:Ribosomal Protein S6 Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one; D004121:Dimethyl Sulfoxide