Met receptor tyrosine kinase transactivation is involved in proteinase-activated receptor-2-mediated hepatocellular carcinoma cell invasion.
The expression of proteinase-activated receptor (PAR)(2) in human hepatocellular carcinoma (HCC) was established by reverse transcription-polymerase chain reaction, confocal immunofluorescence and electron microscopy in permanent cell lines, primary HCC cell cultures and HCC tumor tissue. Stimulation of HCC cells with trypsin and the PAR(2)-selective activating peptide, 2-furoyl-LIGRLO-NH(2), increased cell invasion across Matrigel. Both effects were blocked by a PAR(2)-selective pepducin antagonist peptide (pal-PAR(2)) and by PAR(2) silencing with specific small interfering RNA (siRNA). PAR(2)-initiated HCC cell invasion was also blocked by inhibiting the hepatocyte growth factor receptor (Met receptor tyrosine kinase) with the receptor-targeted kinase inhibitors, SU 11274 and PHA 665752, or by downregulation of Met with specific siRNA. The involvement of Met in PAR(2)-mediated HCC invasive signaling was further supported by the finding that treatment of HCC cells with trypsin or the PAR(2)-selective agonist peptide, 2-furoyl-LIGRLO-NH(2), stimulated Met activation-phosphorylation. In addition, Met-dependent stimulation of p42/p44 mitogen-activated protein Kinases was found to be critical for the PAR(2)-Met receptor tyrosine kinase-invasive signaling axis in HCC cells. Our study establishes an important link between the PAR(2) and Met receptor tyrosine kinase signaling in promoting HCC cell invasion.
Kaufmann
Roland
R
Department of General, Visceral and Vascular Surgery, Research Center Lobeda Medical Faculty, Friedrich Schiller University Jena, D-07747 Jena, Germany. roland.kaufmann@med.uni-jena.de
Oettel
Claudia
C
Horn
Antje
A
Halbhuber
Karl-Jürgen
KJ
Eitner
Annett
A
Krieg
Reimar
R
Katenkamp
Kathrin
K
Henklein
Peter
P
Westermann
Martin
M
Böhmer
Frank D
FD
Ramachandran
Rithwik
R
Saifeddine
Mahmoud
M
Hollenberg
Morley D
MD
Settmacher
Utz
U
D000595:Amino Acid Sequence; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D045744:Cell Line, Tumor; D048049:Extracellular Signal-Regulated MAP Kinases / Q000502:physiology; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology*; D008969:Molecular Sequence Data; D009361:Neoplasm Invasiveness; D010766:Phosphorylation; D011518:Proto-Oncogene Proteins / Q000502:physiology*; D019859:Proto-Oncogene Proteins c-met; D017382:Reactive Oxygen Species / Q000378:metabolism; D044464:Receptor, PAR-2 / Q000032:analysis / Q000502:physiology*; D017978:Receptors, Growth Factor / Q000502:physiology*; D015533:Transcriptional Activation
D011518:Proto-Oncogene Proteins; D017382:Reactive Oxygen Species; D044464:Receptor, PAR-2; D017978:Receptors, Growth Factor; C491743:MET protein, human; D019859:Proto-Oncogene Proteins c-met; D048049:Extracellular Signal-Regulated MAP Kinases