Article

# The extracellular matrix remodeled

01/2012; 5(1):71-3. DOI: 10.4161/cib.17342
Source: PubMed

ABSTRACT

Membrane Type-1 Matrix Metalloproteinase (MT1-MMP, MMP-14) is regarded as the prototype of a membrane- tethered protease. It drives fundamental biological processes ranging from embryogenesis to cancer metastasis. The proteolytic cleavage of proteins by MT1-MMP can rapidly alter the biophysical properties of a cell's microenvironment. Cell's must thus be able to sense and react to these alterations and transduce these effectively in biochemical signals and cell responses. Although many cells react as acutely to such physical stimuli as they do to chemical ones, the regulatory effects of these have been less extensively explored. In order to investigate a possible interdependency of proteolytic matrix cleavage by MT1-MMP and the generation and sensing of force by cells, a model system was established which exploits the properties of a matrix array of parallel collagen-I fibers. The resulting an-isotropy of the matrix with high tensile strength along the fibers and high mobility perpendicular to it allows the convenient detection of bundling and cleavage of the collagen fibers, as well as spreading and durotaxis of the cells. In summary, we have demonstrated that cell adhesion, force generation, and force sensing are vital for the regulation of MT1-MMP for efficient cleavage of collagen-I.

### Full-text

Available from: Robert Kirmse
• Source
• "It may be reasonable to expect greater MMP expression at that interface, where remodeling of the extracellular matrix occurs. Interestingly, MMP-14 is known to respond not only to chemical but also physical stimuli [19,20]. It may be that the increasing pressure in the growing follicle stimulates MMP-14 expression and activity. "
##### Article: Immunohistochemical expression of MMP-14 and MMP-2, and MMP-2 activity during human ovarian follicular development
[Hide abstract]
ABSTRACT: The aim of this study was to investigate the presence of MMP-14 and MMP-2 during human ovarian follicular development using immunohistochemistry, and the activity of MMP-2 in follicular fluid using zymography. Ovarian tissue collected from the archives of the Department of Pathology was examined and medical records and histopathology were reviewed. Follicular fluids were collected at the IVF-department and analyzed using zymography. MMP-14 and MMP-2 were increasingly found in the growing follicles and MMP-2 was highly expressed in the corpus luteum. Pro-MMP-2 was present in follicular fluid of IVF-patients. The presence of MMP-14 and MMP-2 during human ovarian follicular development from the primordial follicle to the tertiary follicle and corpus luteum is confirmed, as was indicated by earlier animal studies following stimulation with gonadotrophins.
Full-text · Article · Jan 2014 · Reproductive Biology and Endocrinology
• ##### Article: At the leading edge of three-dimensional cell migration
[Hide abstract]
ABSTRACT: Cells migrating on flat two-dimensional (2D) surfaces use actin polymerization to extend the leading edge of the plasma membrane during lamellipodia-based migration. This mode of migration is not universal; it represents only one of several mechanisms of cell motility in three-dimensional (3D) environments. The distinct modes of 3D migration are strongly dependent on the physical properties of the extracellular matrix, and they can be distinguished by the structure of the leading edge and the degree of matrix adhesion. How are these distinct modes of cell motility in 3D environments related to each other and regulated? Recent studies show that the same type of cell migrating in 3D extracellular matrix can switch between different leading edge structures. This mode-switching behavior, or plasticity, by a single cell suggests that the apparent diversity of motility mechanisms is integrated by a common intracellular signaling pathway that governs the mode of cell migration. In this Commentary, we propose that the mode of 3D cell migration is governed by a signaling axis involving cell-matrix adhesions, RhoA signaling and actomyosin contractility, and that this might represent a universal mechanism that controls 3D cell migration.
No preview · Article · Feb 2013 · Journal of Cell Science
• Source
##### Article: 1-integrin and MT1-MMP promote tumor cell migration in 2D but not in 3D fibronectin microenvironments
[Hide abstract]
ABSTRACT: Cell migration is a crucial event for physiological processes, such as embryonic development and wound healing, as well as for pathological processes, such as cancer dissemination and metastasis formation. Cancer cell migration is a result of the concerted action of matrix metalloproteinases (MMPs), expressed by cancer cells to degrade the surrounding matrix, and integrins, the transmembrane receptors responsible for cell binding to matrix proteins. While it is known that cell-microenvironment interactions are essential for migration, the role of the physical state of such interactions remains still unclear. In this study we investigated human fibrosarcoma cell migration in two-dimensional (2D) and three-dimensional (3D) fibronectin (FN) microenvironments. By using antibody blocking approach and cell-binding site mutation, we determined that $\upalpha _{5}\upbeta _{1}$ -integrin is the main mediator of fibrosarcoma cell migration in 2D FN, whereas in 3D fibrillar FN, the binding of $\upalpha _{5}\upbeta _{1}$ - and $\upalpha _\mathrm{v}\upbeta _{3}$ -integrins is not necessary for cell movement in the fibrillar network. Furthermore, while the general inhibition of MMPs with GM6001 has no effect on cell migration in both 2D and 3D FN matrices, we observed opposing effect after targeted silencing of a membrane-bound MMP, namely MT1-MMP. In 2D fibronectin, silencing of MT1-MMP results in decreased migration speed and loss of directionality, whereas in 3D FN matrices, cell migration speed is increased and integrin-mediated signaling for actin dynamics is promoted. Our results suggest that the fibrillar nature of the matrix governs the migratory behavior of fibrosarcoma cells. Therefore, to hinder migration and dissemination of diseased cells, matrix molecules should be directly targeted, rather than specific subtypes of receptors at the cell membrane.
Full-text · Article · Mar 2014 · Computational Mechanics