PIN1 and breast cancer: Next, we focused on TALL-1 invasive properties, since it has been demonstrated that high levels of Pin1 correlate with high tumor grade and aggressiveness in breast cancer.27 By using matrigel-coated invasion chambers to simulate extracellular matrix, known to be degraded during tumor dissemination,28 we observed a significant decrease in the invasion of Pin1-silenced TALL-1 cells when compared with the control cells (Figure 2b, left panel).