MMP9 and neoplasm: Notably, this reduction correlates with the decrease in the pro-invasive matrix metalloproteinase MMP9 expression levels (Figure 2b, right panel), known to be involved in the extracellular matrix degradation, thus promoting tumor progression.29, 30 Furthermore, as shown in Figure 2c, when Pin1 silencing was combined with Notch3 blocking, we observed a significantly higher decrease in the activated-N3IC protein levels with respect to control cells, or Pin1 or Notch3 singly inhibited (Figure 2c).