Inhibition of tumour cell invasion by protease inhibitors: correlation with the protease profile

Abstract

The invasive potential of eight established human tumour cell lines of different origin has been studied in the Matrigel assay. Between 25% and 70% of the cells migrated through the Matrigel layer within 24 h, indicating that invasiveness varies with the cell type. Semiquantitative measurements of the proteases MMP-2 and MMP-9, and cathepsins B and L were performed in these cell lines and the cell culture media. High invasive potential was found in those cell lines expressing high levels of cathepsins B and L or matrix metal proteases (MMP), either alone or in combination. Overexpression of one of these enzymes is enough to explain a high invasive potential of a cell line. Selective protease inhibitors at 10 nM concentration in the culture medium were used to inhibit the migration of tumour cells in the Matrigel assay. The MMP inhibitor Batimastat reduced the invasive potential of all cell lines studied independently of the MMP expression. The effect of cysteine protease inhibitors was strongly correlated with the protease profile of the tumour cell line. Our findings support the hypothesis of a very complex activation cascade of matrix-degrading proteolytic enzymes and they underline the need to analyse the protease profile of any tumour before beginning an antiproteolytic tumour treatment.

Cystatin C Properties Crucial for Uptake and Inhibition of Intracellular Target Enzymes

“…The human breast adenocarcinoma cell line MCF-7 was chosen for further analysis as it was previously used in studies of the effect of protease inhibition on cancer cell metabolism (23,24). The focus of this work was to delineate the first part of the internalization pathway by analyzing the importance of charge and hydrophobicity for uptake, as these properties have been shown to contribute to cellular internalization (26 -28) to study the subcellular localization of the internalized inhibitor and the intracellular effects of the uptake.…”

“…Basic Uptake Kinetics for Cystatin C-The MCF-7 cell line was selected for detailed studies on molecular requirements for cystatin C uptake (see Introduction), partly because it has been shown that both cell permeable and non-cell-permeable lowmolecular-weight cysteine protease inhibitors have effects on its migration and invasion (23,24). To test whether cystatin C can affect such biologically relevant properties of these cells, we performed Matrigel experiments comparing cells incubated with and without cystatin C (1 M) added to the medium.…”

Down-regulation of cathepsin B expression impairs the invasive and tumorigenic potential of human glioblastoma cells

“…The ®ndings obtained in the in vitro invasion assays are in accordance with the results obtained by the selective cysteine protease inhibitors in murine squamous carcinoma cells (Coulibaly et al, 1999) and glioblastoma cells (Demchik et al, 1999), demonstrating that cathepsin B can mediate the degradation of ECM components. Kolkhorst et al (1998) found that invasiveness of tumor cell lines expressing high levels of cathepsin B are e ciently inhibited by CA074, a selective cathepsin B inhibitor. In a recent study, cathepsin B antisense-transfected human osteosarcoma cells showed a markedly lower invasiveness and motility in Matrigel invasion assays than did controls (Krueger et al, 1999).…”

New insights into the role of extracellular matrix during tumor onset and progression

“…Most of these enzymes are lysosomal proteases that are involved in physiological process such as turnover of cellular proteins. Immunohistochemical and enzymatic analyses of protease expression in different tumors have shown that increased expression or changes in cell localization are important prognostic factors and correlated with tumor progression (Heck et al, 1990;Kolkhorst et al, 1998;Yan et al, 1998;Tetu et al, 1999). However, in the remodeling process, most enzymes are produced by stromal cells of the host (Crawford and Matrisian, 1996;Saren et al, 1996).…”