title: Activation of matrix metalloproteinase-2 (MMP-2) by membrane type 1 matrix metalloproteinase through an artificial receptor for proMMP-2 generates active MMP-2.
abstract: The suggested model for pro-matrix metalloproteinase-2 (proMMP-2) activation by membrane type 1 MMP (MT1-MMP) implicates the complex between MT1-MMP and tissue inhibitor of MMP-2 (TIMP-2) as a receptor for proMMP-2. To dissect this model and assess the pathologic significance of MMP-2 activation, an artificial receptor for proMMP-2 was created by replacing the signal sequence of TIMP-2 with cytoplasmic/transmembrane domain of type II transmembrane mosaic serine protease (MSP-T2). Unlike TIMP-2, MSP-T2 served as a receptor for proMMP-2 without inhibiting MT1-MMP, and generated TIMP-2-free active MMP-2 even at a low level of MT1-MMP. Thus, MSP-T2 did not affect direct cleavage of the substrate testican-1 by MT1-MMP, whereas TIMP-2 inhibited it even at the level that stimulates proMMP-2 processing. Expression of MSP-T2 in HT1080 cells enhanced MMP-2 activation by endogenous MT1-MMP and caused intensive hydrolysis of collagen gel. Expression of MSP-T2 in U87 glioma cells, which express a trace level of endogenous MT1-MMP, induced MMP-2 activation and enhanced cell-associated protease activity, activation of extracellular signal-regulated kinase, and metastatic ability into chick embryonic liver and lung. MT1-MMP can exert both maximum MMP-2 activation and direct cleavage of substrates with MSP-T2, which cannot be achieved with TIMP-2. These results suggest that MMP-2 activation by MT1-MMP potentially amplifies protease activity, and combination with direct cleavage of substrate causes effective tissue degradation and enhances tumor invasion and metastasis, which highlights the complex role of TIMP-2. MSP-T2 is a unique tool to analyze physiologic and pathologic roles of MMP-2 and MT1-MMP in comparison with TIMP-2.
authors.affiliation: Department of Molecular Virology and Oncology, Cancer Research Institute, Kanazawa University, Takara-machi, Kanazawa, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Nishida
authors.forename: Hisashi
authors.initials: H
authors.lastname: Miyamori
authors.forename: Erik W
authors.initials: EW
authors.lastname: Thompson
authors.forename: Takahisa
authors.initials: T
authors.lastname: Takino
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Endo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sato
mesh_terms: D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D045744:Cell Line, Tumor; D002642:Chick Embryo; D017931:DNA Primers; D004789:Enzyme Activation; D006801:Humans; D053511:Matrix Metalloproteinase 14 / Q000378:metabolism*; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D009362:Neoplasm Metastasis; D010766:Phosphorylation; D016133:Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D020778:Matrix Metalloproteinase 2; D053511:Matrix Metalloproteinase 14