Figure 2.

Ranpirnase impairs MMP9 release and cell invasiveness induced by TNF-α in mesothelioma (MM) cells. (A) Gelatin zymography was performed, as described in Materials and Methods, on conditioned media from PPM-Mill and REN cells. Cells were preincubated for 72 hours with the indicated concentrations of ranpirnase (ONC) or with vehicle (-), followed by a treatment with TNF-α (10 ng/mL) for 30 minutes (+). A sharp reduction of MMP9 activity is evident at both ranpirnase concentrations. (B) Cell invasion was assessed by Matrigel-coated Transwell, as described in Materials and Methods. In both MM cell lines, TNF-α strongly induced cell invasiveness, which was inhibited by ranpirnase (ONC) in a dose-dependent manner. (C) The numbers of cells invading the coated membrane of the Transwell top chamber were quantified by Image-J software and are shown by the bar graph. Asterisks (*) indicate P < 0.05 significance.