TY - JOUR
T1 - Plasminogen activator inhibitor-1 represses integrin- and vitronectin-mediated cell migration independently of its function as an inhibitor of plasminogen activation
AU - Kjøller, L
AU - Kanse, S M
AU - Kirkegaard, T
AU - Rodenburg, K W
AU - Rønne, E
AU - Goodman, S L
AU - Preissner, K T
AU - Ossowski, L
AU - Andreasen, P A
PY - 1997/5/1
Y1 - 1997/5/1
N2 - Cell migration involves the integrins, their extracellular matrix ligands, and pericellular proteolytic enzyme systems. We have studied the role of plasminogen activator inhibitor-1 (PAI-1) in cell migration, using human amnion WISH cells and human epidermoid carcinoma HEp-2 cells in an assay measuring migration from microcarrier beads and a modified Boyden-chamber assay. Active, but not latent or reactive center-cleaved, PAI-1 inhibited migration. A PAI-1 mutant without ability to inhibit plasminogen activation was as active as wild-type PAI-1 as a migration inhibitor, showing that inhibition of plasminogen activation was not involved. PAI-1 specifically interfered with intergrin- and vitronectin-mediated migration: Migration onto vitronectin-coated but not onto fibronectin-coated surfaces was inhibited by PAI-1, a cyclic RGD peptide inhibited migration, and both cell lines expressed vitronectin-binding alpha v-integrins. In addition, active PAI-1, but not latent or reactive center-cleaved PAI-1, inhibited vitronectin binding to integrins in an in vitro binding assay, without affecting binding of fibronectin. Monoclonal antibodies against the urokinase receptor, another vitronectin binding protein, did not affect cell migration in the beads assay, while some inhibitory effect was observed in the Boyden-chamber assay. We conclude that PAI-1, independently of its role as a proteinase inhibitor, inhibits cell migration by competing for vitronectin binding to integrins, while the interference of PAI-1 with binding of vitronectin to the urokinase receptor may play a secondary role. These data define a novel function for the serpin PAI-1, enabling it to regulate cell migration over vitronectin-rich extracellular matrix in the body.
AB - Cell migration involves the integrins, their extracellular matrix ligands, and pericellular proteolytic enzyme systems. We have studied the role of plasminogen activator inhibitor-1 (PAI-1) in cell migration, using human amnion WISH cells and human epidermoid carcinoma HEp-2 cells in an assay measuring migration from microcarrier beads and a modified Boyden-chamber assay. Active, but not latent or reactive center-cleaved, PAI-1 inhibited migration. A PAI-1 mutant without ability to inhibit plasminogen activation was as active as wild-type PAI-1 as a migration inhibitor, showing that inhibition of plasminogen activation was not involved. PAI-1 specifically interfered with intergrin- and vitronectin-mediated migration: Migration onto vitronectin-coated but not onto fibronectin-coated surfaces was inhibited by PAI-1, a cyclic RGD peptide inhibited migration, and both cell lines expressed vitronectin-binding alpha v-integrins. In addition, active PAI-1, but not latent or reactive center-cleaved PAI-1, inhibited vitronectin binding to integrins in an in vitro binding assay, without affecting binding of fibronectin. Monoclonal antibodies against the urokinase receptor, another vitronectin binding protein, did not affect cell migration in the beads assay, while some inhibitory effect was observed in the Boyden-chamber assay. We conclude that PAI-1, independently of its role as a proteinase inhibitor, inhibits cell migration by competing for vitronectin binding to integrins, while the interference of PAI-1 with binding of vitronectin to the urokinase receptor may play a secondary role. These data define a novel function for the serpin PAI-1, enabling it to regulate cell migration over vitronectin-rich extracellular matrix in the body.
KW - Amnion/cytology
KW - Carcinoma, Squamous Cell/pathology
KW - Cell Line
KW - Cell Movement/drug effects
KW - Culture Media, Serum-Free
KW - Enzyme Activation/drug effects
KW - Extracellular Matrix/metabolism
KW - Humans
KW - Integrins/physiology
KW - Neoplasm Proteins/physiology
KW - Oligopeptides/pharmacology
KW - Peptides, Cyclic/pharmacology
KW - Plasminogen/metabolism
KW - Plasminogen Activator Inhibitor 1/chemistry
KW - Protein Conformation
KW - Receptors, Cell Surface/physiology
KW - Receptors, Urokinase Plasminogen Activator
KW - Tumor Cells, Cultured
KW - Urokinase-Type Plasminogen Activator/physiology
KW - Vitronectin/physiology
U2 - 10.1006/excr.1997.3540
DO - 10.1006/excr.1997.3540
M3 - Article
C2 - 9168821
SN - 0014-4827
VL - 232
SP - 420
EP - 429
JO - Experimental Cell Research
JF - Experimental Cell Research
IS - 2
ER -