Phosphatidylinositol 3-kinase contributes to Erk1/Erk2 MAP kinase activation associated with hepatocyte growth factor-induced cell scattering.
MAP kinase cascade-dependent responses were investigated during scattering of HepG2 human hepatoma cells stimulated by HGF or phorbol ester. Inhibition of phosphatidylinositol 3-kinase with LY294002 prevented completely the dissociation of cells. Inhibition of MAP kinase kinase (MEK) with PD98059 prevented the development of characteristic morphological changes associated with cell migration. EGF, which failed to induce cell scattering, caused a short-term increase in the phosphorylation of Erk1/Erk2 MAP kinases. On the contrary, HGF or phorbol ester stimulated the phosphorylation of MAP kinases for a long time. Experiments performed with LY294002 indicated that phosphatidylinositol 3-kinase contributed to the HGF-stimulated phosphorylation of Erk1/Erk2. This finding was confirmed by the demonstration that the MAP kinase cascade-dependent expression of a high-Mr (>300 kDa) protein pair appearing in the course of cell scattering was inhibited by LY294002 in HGF-induced cells but was not inhibited in phorbol ester-treated cells.
Sipeki
S
S
Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University of Medicine, Budapest, Hungary.
Bander
E
E
Buday
L
L
Farkas
G
G
Bácsy
E
E
Ways
D K
DK
Faragó
A
A
D006528:Carcinoma, Hepatocellular / Q000473:pathology; D002465:Cell Movement / Q000187:drug effects; D002867:Chromones / Q000494:pharmacology; D003513:Cycloheximide / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D017228:Hepatocyte Growth Factor / Q000494:pharmacology*; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology; D020935:MAP Kinase Signaling System / Q000187:drug effects* / Q000502:physiology; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000502:physiology; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009025:Morpholines / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000502:physiology; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation / Q000187:drug effects; D011499:Protein Processing, Post-Translational / Q000187:drug effects; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000502:physiology; D050721:Proto-Oncogene Proteins c-cbl; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014407:Tumor Cells, Cultured / Q000187:drug effects; D044767:Ubiquitin-Protein Ligases
D002867:Chromones; D003513:Cycloheximide; D004791:Enzyme Inhibitors; D005419:Flavonoids; D017228:Hepatocyte Growth Factor; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases; D020928:Mitogen-Activated Protein Kinases; D009025:Morpholines; D009363:Neoplasm Proteins; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D011500:Protein Synthesis Inhibitors; D011518:Proto-Oncogene Proteins; D050721:Proto-Oncogene Proteins c-cbl; D013755:Tetradecanoylphorbol Acetate; D044767:Ubiquitin-Protein Ligases; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; C067419:CBL protein, human; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one