title: Functional interplay between type I collagen and cell surface matrix metalloproteinase activity.
abstract: Type I collagen stimulation of pro-matrix metalloproteinase (pro-MMP)-2 activation by ovarian cancer cells involves beta(1) integrin receptor clustering; however, the specific cellular and biochemical events that accompany MMP processing are not well characterized. Collagenolysis is not required for stimulation of pro-MMP-2 activation, and denatured collagen does not elicit an MMP-2 activation response. Similarly, DOV13 cells bind to intact collagen utilizing both alpha(2)beta(1) and alpha(3)beta(1) integrins but interact poorly with collagenase-treated or thermally denatured collagen. Antibody-induced clustering of alpha(3)beta(1) strongly promotes activation of pro-MMP-2, whereas alpha(2)beta(1) integrin clustering has only marginal effects. Membrane-type 1 (MT1)-MMP is present on the DOV13 cell surface as both an active 55-kDa TIMP-2-binding species and a stable catalytically inactive 43-kDa form. Integrin clustering stimulates cell surface expression of MT1-MMP and co-localization of the proteinase to aggregated integrin complexes. Furthermore, cell surface proteolysis of the 55-kDa MT1-MMP species occurs in the absence of active MMP-2, suggesting MT1-MMP autolysis. Cellular invasion of type I collagen matrices requires collagenase activity, is blocked by tissue inhibitor of metalloproteinases-2 (TIMP-2) and collagenase-resistant collagen, is unaffected by TIMP-1, and is accompanied by pro-MMP-2 activation. Together, these data indicate that integrin stimulation of MT1-MMP activity is a rate-limiting step for type I collagen invasion and provide a mechanism by which this activity can be down-regulated following collagen clearance.
authors.affiliation: Department of Cell and Molecular Biology, Northwestern University Medical School, 303 E. Chicago Ave., Chicago, IL 60611, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Ellerbroek
authors.forename: Y I
authors.initials: YI
authors.lastname: Wu
authors.forename: C M
authors.initials: CM
authors.lastname: Overall
authors.forename: M S
authors.initials: MS
authors.lastname: Stack
mesh_terms: D002448:Cell Adhesion; D002460:Cell Line; D003094:Collagen / Q000378:metabolism*; D004789:Enzyme Activation; D004792:Enzyme Precursors / Q000378:metabolism; D005260:Female; D018093:Gelatinases / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D016023:Integrins / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020782:Matrix Metalloproteinases / Q000378:metabolism*; D008666:Metalloendopeptidases / Q000378:metabolism; D008970:Molecular Weight; D010051:Ovarian Neoplasms / Q000201:enzymology; D013329:Structure-Activity Relationship; D013499:Surface Properties; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D004792:Enzyme Precursors; D016023:Integrins; D019716:Tissue Inhibitor of Metalloproteinase-2; D003094:Collagen; D018093:Gelatinases; D020782:Matrix Metalloproteinases; D008666:Metalloendopeptidases; C069860:progelatinase; D020778:Matrix Metalloproteinase 2