title: Constitutive activation of MAP kinase kinase (MEK1) is critical and sufficient for the activation of MMP-2.
abstract: We investigated the role of MEK1 signaling in MMP-2 activation by use of constitutive active/dominant negative forms of MEK1 and MEK1-specific inhibitor. We found that cell transformation with active forms of MEK1 dramatically increased secretion and proteolytic activation of MMP-2 and subsequently stimulated invasiveness of cells. Contrary, expression of dominant negative form of MEK1 in v-src-transformed cells or in Con A-activated cells resulted in the suppression of the augmented secretion and proteolytic activation of MMP-2. In addition, treatment of v-src-transformed cells with PD98059, a MEK1-specific inhibitor, strongly suppressed the secretion and activation of MMP-2, whereas treatment with wortmannin, a PI3 kinase inhibitor, showed no clear effect on MMP-2 secretion. Taken together, these results strongly suggest that MEK-MAP kinase signaling, but not PI3 kinase signaling, plays a critical role in the activation of MMP-2 secretion and, subsequently, in the invasiveness of v-src-transformed cells.
authors.affiliation: Department of Internal Medicine III, Department of Molecular Pathogenesis, Nagoya University School of Medicine, 65 Tsurumai-cho, Nagoya, 466-8550, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kurata
authors.forename: A A
authors.initials: AA
authors.lastname: Thant
authors.forename: S
authors.initials: S
authors.lastname: Matsuo
authors.forename: T
authors.initials: T
authors.lastname: Senga
authors.forename: K
authors.initials: K
authors.lastname: Okazaki
authors.forename: N
authors.initials: N
authors.lastname: Hotta
authors.forename: M
authors.initials: M
authors.lastname: Hamaguchi
mesh_terms: D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D002460:Cell Line; D003208:Concanavalin A / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D048369:MAP Kinase Kinase 1; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D020929:Mitogen-Activated Protein Kinase Kinases / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases; D051381:Rats; D014162:Transfection
chemical_list: D004791:Enzyme Inhibitors; D005419:Flavonoids; D003208:Concanavalin A; D017346:Protein Serine-Threonine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048369:MAP Kinase Kinase 1; D020929:Mitogen-Activated Protein Kinase Kinases; D020778:Matrix Metalloproteinase 2; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one