title: Protein kinase C modulates negatively the hepatocyte growth factor-induced migration, integrin expression and phosphatidylinositol 3-kinase activation.
abstract: Previously, we reported that, in hepatocyte growth factor (HGF)-induced HepG2 cells, protein kinase C (PKC) decreased the duration of intensive Erk1/Erk2 MAP kinase activation. This study shows that the inhibition of PKC enhanced significantly the HGF-induced integrin expression. Beside the prolonged activation of Erk1/Erk2, the activity of phosphatidylinositol 3-kinase (PI 3K) was required for growth factor-induced integrin expression. PI 3-kinase was activated to a higher extent in response to HGF than to epidermal growth factor (EGF), though the activation was transient in both cases. In EGF-induced cells, PI 3K activation was terminated by the loss of phosphotyrosine docking sites for PI 3K. To the contrary, the decrease of PI 3K activation, which followed the HGF-induced increase was not accompanied by the loss of phosphotyrosine docking sites and was prevented by the inhibition of PKC. The negative modulator effects of PKC on integrin expression and PI 3-kinase activation correlated with its ability to limit the HGF-induced motogen response.
authors.affiliation: Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, P.O. Box 260, 1444, Budapest, Hungary.
authors.forename: Annamária
authors.initials: A
authors.lastname: Gujdár
authors.forename: Szabolcs
authors.initials: S
authors.lastname: Sipeki
authors.forename: Erzsébet
authors.initials: E
authors.lastname: Bander
authors.forename: László
authors.initials: L
authors.lastname: Buday
authors.forename: Anna
authors.initials: A
authors.lastname: Faragó
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000378:metabolism*; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004815:Epidermal Growth Factor / Q000378:metabolism; D017228:Hepatocyte Growth Factor / Q000494:pharmacology*; D006801:Humans; D016023:Integrins / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000502:physiology; D010703:Phorbol Esters / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D004791:Enzyme Inhibitors; D016023:Integrins; D010703:Phorbol Esters; D004815:Epidermal Growth Factor; D017228:Hepatocyte Growth Factor; D019869:Phosphatidylinositol 3-Kinases; D011493:Protein Kinase C