Tissue Inhibitor of Matrix Metalloproteinase-2 Regulates Matrix Metalloproteinase-2 Activation by Modulation of Membrane-type 1 Matrix Metalloproteinase Activity in High and Low Invasive Melanoma Cell Lines

Abstract

Activation of pro-matrix metalloproteinase (MMP)-2 on the surface of malignant cells by membrane-bound MT1-MMP is believed to play a critical role during tumor progression and metastasis. In this study we present evidence that MT1-MMP plays a key role for the in vitro invasiveness of malignant melanoma. Melanoma cell lines secreted latent MMP-2 when cultured on plastic. However, when cells were grown in floating type I collagen lattices, only high invasive melanoma cells activated proMMP-2. Activation could be inhibited by antibodies against MT1-MMP, by addition of recombinant tissue inhibitor of metalloproteinases (TIMP)-2 and by inhibition of MT1-MMP cleavage. MT1-MMP protein was detected as an inactive protein in all cell lines cultured as monolayers, whereas in collagen gels, active MT1-MMP protein was detected in the membranes of both high and low invasive melanoma cells. Production of TIMP-2 was about 10-fold higher in low invasive cells as compared with high invasive melanoma cells and was further increased in the low invasive cells upon contact to collagen. Thus, in melanoma cells TIMP-2 expression levels might regulate MT1-MMP-mediated activation of proMMP-2. High invasive melanoma cells displayed increased in vitro invasiveness, which was inhibited by TIMP-2. These data indicate the importance of these enzymes for the invasion processes and support a role for MT1-MMP as an activator of proMMP-2 in malignant melanoma.Local degradation of connective tissue in the vicinity of the cell surface is thought to be essential for tumor cell invasion and metastasis. Neoplastic cells that invade surrounding tissues and metastasize through the blood stream or lymphatic system must penetrate several barriers, including basement membranes and the interstitial connective tissue (1, 2). Degradation of extracellular matrix components is accomplished through the combined action of different proteases, primarily of the matrix metalloproteinase (MMP) 1 (3) and serine protease families (4).Because of the importance of MMP activity for initiating efficient matrix degradation, MMP expression and activity is tightly regulated and is subject to several levels of control, including gene transcription, post-translational extracellular activation, and inhibition by soluble inhibitors (3, 5). Basal production of metalloproteinases is typically low or absent and requires an inducing factor, such as a cytokine, phorbol ester, or contact with components of the extracellular matrix to increase their expression (3). Enzyme activation is achieved by removal of the N-terminal propeptide domain through exogenous or autocatalytic cleavage. In vitro, serine proteases, such as plasmin or trypsin, have been shown to activate most MMPs (3). However, MMP-2 is unique among the MMPs in that its expression is constitutive and its activation can be achieved in a membrane-associated manner as has been shown for fibroblasts (6), for endothelial cells (7,8), and for tumor cells (9 -11). A novel membrane-type matrix metalloproteinase (MT1-MMP) was origi...

Inhibition of furin‐like enzymes blocks interleukin‐1α/oncostatin M–stimulated cartilage degradation

“…Indeed, we showed that Dec-RVKR-CH 2 Cl reduced proMMP-2 activation in stimulated cartilage. This is consistent with the results of several previous studies, which have shown that the addition of Dec-RVKR-CH 2 Cl to cell cultures prevents proMMP-2 activation by blocking furin-dependent activation of proMT-MMPs (39,(57)(58)(59)(60).…”

Basigin (cd147) is expressed on melanoma cells and induces tumor cell invasion by stimulating production of matrix metalloproteinases by fibroblasts

“…40 Induction of the activated form of MMP-2 was associated with enhanced expression of MT1-MMP, which activates MMP-2. 25,27,28 These results suggest that basigin stimulates activation as …”

“…20 MT1-MMP triggers tumor invasion by activating MMP-2. 25,27,28 Cutaneous MM is characterized by a high potential for invasion and metastasis. Previous studies reported the involvement of MMPs in migration, invasion, metastasis and progression of MM.…”

Regulation of Membrane Type-1 Matrix Metalloproteinase Activation by Proprotein Convertases

“…Based on our findings that COS-1 cells can process wild-type MT1-MMP as well as its 108 RRKR mutant, coupled with the recent demonstration that ␣ 1 PI PITT is unable to efficiently inhibit proprotein convertase-dependent pathways (Vollenweider et al, 1996;Cui et al, 1998), we propose that the removal of the MT1-MMP prodomain is a prerequisite for the efficient display of proteolytic activity. Interestingly, although partial blockade of proMT1-MMP processing was reported recently with a chloromethylketone inhibitor (Maquoi et al, 1998;Kurschat et al, 1999), this agent is not specific for proprotein convertases and also exerts cytotoxic effects (Hallenberger et al, 1992;Okumura et al, 1997;Jean et al, 1998).…”