Measuring CRC Cell Gelatinolytic Activity

CRC cells were incubated with PMPs as described above, and 50 × 10³ cells per ml were added to FITC-labelled gelatine-coated wells (0.1 mg/ml) and incubated for 24 h. The gelatinolytic activity of MMP-2 and MMP-9 was measured as green fluorescence derived from degraded gelatine (Additional file 2: Supplementary Methods). In another set of experiments, MMP-2 and MMP-9 activity was measured as CRC cell migration through 0.2% gelatin-coated filters in the Boyden chambers as described above (Additional file 2: Supplementary Methods). The gelatinolytic properties of CRC cell were blocked by the appropriate inhibitors of MMP-2 (ARP101) or MMP-9 (CTK8G1150) at a final concentration of 20 µM or by the specific inhibitor of p38MAPK (SB202190, Cell Signaling Technology) at a final concentration of 5 µM.