c-jun amino-terminal kinase and mitogen activated protein kinase 1/2 mediate hepatocyte growth factor-induced migration of brain endothelial cells.
Hepatocyte growth factor (HGF) influences several components of the angiogenic response, including endothelial cell migration. While recent studies indicate a crucial role of HGF in brain angiogenesis, the signaling pathways that regulate brain endothelial cell migration by HGF remain uncharacterized. Herein, we report that HGF stimulated human brain microvascular endothelial cell (HBMEC) migration in a dose- and time-dependent manner. Challenge of HBMECs with HGF activated the c-jun amino-terminal kinase (JNK), increased phosphorylation of the proline-rich tyrosine kinase 2 (Pyk-2) at Tyr(402) and activated c-Src. Inhibition of JNK by SP600125 or expression of a dominant negative JNK1 construct abrogated the migratory response of HBMECs to HGF. Treatment of HBMECs with the Src inhibitor PP2 markedly decreased HGF-stimulated JNK activation and migration to HGF. Moreover, expression of a mutant Pyk-2 construct prevented HGF-induced Pyk-2 phosphorylation at Tyr(402) and stimulation of HBMEC migration. Next, we examined activation of the extracellular signal regulated kinase (ERK) pathway. Stimulation of HBMECs by HGF led to rapid activation of ERK1/2, phosphorylation of Raf-1 at Ser(338) and Tyr(340/341) and MEK1/2 at Ser(222). Moreover, inhibition of ERK activation by UO126 and PD98059 markedly decreased HGF-stimulated HBMEC migration. HGF also activated AKT, while inhibition of AKT by LY294002 induced a modest decrease of HGF-induced HBMEC migration. These results highlight a model whereby JNK and ERK play a critical role in regulation of brain endothelial cell migration by HGF.
Rush
Stephen
S
Signal Transduction Laboratory, Methodist Research Institute, Indiana University School of Medicine, Indianapolis, IN, USA.
Khan
Gausal
G
Bamisaiye
Ayoola
A
Bidwell
Philip
P
Leaver
H Anne
HA
Rizzo
Maria Teresa
MT
D001921:Brain / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D051418:Focal Adhesion Kinase 2 / Q000037:antagonists & inhibitors; D017228:Hepatocyte Growth Factor / Q000494:pharmacology*; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D048369:MAP Kinase Kinase 1 / Q000378:metabolism; D048370:MAP Kinase Kinase 2 / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects; D008954:Models, Biological; D010766:Phosphorylation; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019908:Proto-Oncogene Proteins c-raf / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D000076202:c-Mer Tyrosine Kinase; D019061:src-Family Kinases / Q000037:antagonists & inhibitors
D004791:Enzyme Inhibitors; D011518:Proto-Oncogene Proteins; D017228:Hepatocyte Growth Factor; C482128:MAP2K2 protein, human; C097072:MERTK protein, human; D020794:Receptor Protein-Tyrosine Kinases; D000076202:c-Mer Tyrosine Kinase; D051418:Focal Adhesion Kinase 2; D019061:src-Family Kinases; D019908:Proto-Oncogene Proteins c-raf; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D048369:MAP Kinase Kinase 1; D048370:MAP Kinase Kinase 2; C482125:MAP2K1 protein, human