Fig. 4.

CD147-induced, invadopodia-mediated, matrix degradation is dependent on membrane-type MMPs. (A,B) MCF-10A cells infected with CD147 adenovirus were pre-treated with the protease inhibitors, TIMP-1 (0.5 μg/ml) and TIMP-2 (0.5 μg/ml) for 30 minutes and then plated on fluorescent matrices for 12 hours in the presence of these inhibitors. (A) Representative micrographs of matrix degradation in control and CD147-upregulated cells in the presence of protease inhibitors. Scale bars: 10 μm. (B) Quantification of normalized degradation area, expressed as means ± s.e.m. **P≤0.01. The experiment was repeated three times. (C) Western blot of CD147 and MT1-MMP in aliquots of lysates obtained from MCF-10A cells that were cultured on gelatin and treated with control (β-gal) or CD147 adenovirus. Actin was used as a loading control; n=3. (D,E) MCF-10A cells infected with CD147 adenovirus were pre-treated with function-blocking antibody against MT1-MMP (LEM-2/15.8; 12 μg/ml) or control IgG and then plated on fluorescent matrices for 12 hours in the presence of the blocking antibody or IgG. (D) Representative micrographs of matrix degradation in CD147-upregulated cells in the presence of blocking antibody or IgG. Scale bars: 10 μm. (E) Left panel: quantification of normalized degradation area. Right panel: quantification of invasion through the Matrigel. Values are means ± s.e.m. **P≤0.01; ***P≤0.001; experiments were repeated three times.