Enhanced migration of tissue inhibitor of metalloproteinase overexpressing hepatoma cells is attributed to gelatinases: relevance to intracellular signaling pathways.
OBJECTIVE
To study the effect of gelatinases (especially MMP-9) on migration of tissue inhibitor of metalloproteinase (TIMP-1) overexpressing hepatoma cells.


METHODS
Wild type HepG2 cells, cells stably transfected with TIMP-1 and TIMP-1 antagonist (MMP-9-H401A, a catalytically inactive matrix metalloproteinase (MMP) which still binds and neutralizes TIMP-1) were incubated in Boyden chambers either with or without Galardin (a synthetic inhibitor of MMP-1, -2, -3, -8, -9) or a specific inhibitor of gelatinases.


RESULTS
Compared to wild type HepG2 cells, the cells overexpressing TIMP-1 showed 115% migration (P<0.05) and the cells overexpressing MMP-9-H401A showed 62% migration (P<0.01). Galardin reduced cell migration dose dependently in all cases. The gelatinase inhibitor reduced migration in TIMP-1 overexpressing cells predominantly. Furthermore, we examined intracellular signal transduction pathways of TIMP-1-dependent HepG2 cells. TIMP-1 deactivates cell signaling pathways of MMP-2 and MMP-9 involving p38 mitogen-activated protein kinase. Specific blockade of the ERK pathway suppresses gelatinase expression either in the presence or absence of TIMP-1.


CONCLUSIONS
Overexpressing functional TIMP-1- enhanced migration of HepG2-TIMP-1 cells depends on enhanced MMP-activity, especially MMP-9.
Roeb
Elke
E
Department of Internal Medicine III, University Hospital RWTH Aachen, Pauwelsstr. 30, 52057 Aachen, Germany. eroeb@ukaachen.de
Bosserhoff
Anja-Katrin
AK
Hamacher
Sabine
S
Jansen
Bettina
B
Dahmen
Judith
J
Wagner
Sandra
S
Matern
Siegfried
S
D006528:Carcinoma, Hepatocellular; D045744:Cell Line, Tumor / Q000166:cytology / Q000502:physiology; D002465:Cell Movement / Q000502:physiology*; D017364:Collagenases / Q000235:genetics; D004151:Dipeptides / Q000494:pharmacology; D006801:Humans; D008113:Liver Neoplasms; D020781:Matrix Metalloproteinase 1 / Q000235:genetics; D053509:Matrix Metalloproteinase 13; D020778:Matrix Metalloproteinase 2 / Q000235:genetics; D019278:Matrix Metalloproteinase 3 / Q000235:genetics; D020783:Matrix Metalloproteinase 7 / Q000235:genetics; D020780:Matrix Metalloproteinase 9 / Q000235:genetics*; D061965:Matrix Metalloproteinase Inhibitors; D011480:Protease Inhibitors / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics*; D014162:Transfection
D004151:Dipeptides; D061965:Matrix Metalloproteinase Inhibitors; C078131:N-(2(R)-2-(hydroxamidocarbonylmethyl)-4-methylpentanoyl)-L-tryptophan methylamide; D011480:Protease Inhibitors; D019715:Tissue Inhibitor of Metalloproteinase-1; D017364:Collagenases; C507079:MMP13 protein, human; D053509:Matrix Metalloproteinase 13; D019278:Matrix Metalloproteinase 3; D020783:Matrix Metalloproteinase 7; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D020781:Matrix Metalloproteinase 1