title: Mitogen- and stress-activated kinase 1-mediated histone H3 phosphorylation is crucial for cell transformation.
abstract: Mitogen- and stress-activated kinase 1 (MSK1) belongs to a family of dual protein kinases that are activated by either extracellular signal-regulated kinase or p38 mitogen-activated protein kinases in response to stress or mitogenic extracellular stimuli. The physiologic role of MSK1 in malignant transformation and cancer development is not well understood. Here, we report that MSK1 is involved in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced or epidermal growth factor (EGF)-induced neoplastic transformation of JB6 Cl41 cells. H89, a potent inhibitor of MSK1, strongly suppressed TPA-induced or EGF-induced cell transformation. When cells overexpressing wild-type MSK1 were treated with TPA or EGF, colony formation increased substantially compared with untreated cells or cells that did not overexpress MSK1. In contrast, MSK1 COOH terminal or NH(2) terminal dead dominant negative mutants dramatically suppressed cell transformation. Introduction of small interfering RNA-MSK1 into JB6 Cl41 cells resulted in suppressed TPA-induced or EGF-induced cell transformation. In addition, cell proliferation was inhibited in MSK1 knockdown cells compared with MSK1 wild-type cells. In wild-type MSK1-overexpressing cells, activator protein (AP-1) activation increased after TPA or EGF stimulation, whereas AP-1 activation decreased in both MSK1 dominant-negative mutants and in MSK1 knockdown cells. Moreover, TPA-induced or EGF-induced phosphorylation of histone H3 at Ser(10) was increased in wild-type cells but the induced phosphorylation was abolished in MSK1 dominant-negative mutant or MSK1 knockdown cells. Thus, MSK1 is required for tumor promoter-induced cell transformation through its phosphorylation of histone H3 at Ser(10) and AP-1 activation.
authors.affiliation: The Hormel Institute, University of Minnesota, Austin, MN 55912, USA.
authors.forename: Hong-Gyum
authors.initials: HG
authors.lastname: Kim
authors.forename: Ki Won
authors.initials: KW
authors.lastname: Lee
authors.forename: Yong-Yeon
authors.initials: YY
authors.lastname: Cho
authors.forename: Nam Joo
authors.initials: NJ
authors.lastname: Kang
authors.forename: Sang-Muk
authors.initials: SM
authors.lastname: Oh
authors.forename: Ann M
authors.initials: AM
authors.lastname: Bode
authors.forename: Zigang
authors.initials: Z
authors.lastname: Dong
mesh_terms: D000818:Animals; D048708:Cell Growth Processes / Q000187:drug effects / Q000502:physiology; D002471:Cell Transformation, Neoplastic / Q000187:drug effects / Q000378:metabolism*; D004789:Enzyme Activation; D004815:Epidermal Growth Factor / Q000494:pharmacology; D016193:G1 Phase / Q000187:drug effects / Q000502:physiology; D006657:Histones / Q000378:metabolism*; D007546:Isoquinolines / Q000494:pharmacology; D051379:Mice; D010766:Phosphorylation / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D034741:RNA, Small Interfering / Q000235:genetics; D038744:Ribosomal Protein S6 Kinases, 90-kDa / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D012867:Skin / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D013449:Sulfonamides / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D018808:Transcription Factor AP-1 / Q000378:metabolism
chemical_list: D006657:Histones; D007546:Isoquinolines; D047428:Protein Kinase Inhibitors; D034741:RNA, Small Interfering; D013449:Sulfonamides; D018808:Transcription Factor AP-1; D004815:Epidermal Growth Factor; D038744:Ribosomal Protein S6 Kinases, 90-kDa; C116919:mitogen and stress-activated protein kinase 1; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide; D013755:Tetradecanoylphorbol Acetate