Because PKD2 activity regulates the secretion of MMPs in other tumor cell lines (Eiseler et al., 2016), it could be speculated that pharmacological inhibition of PKD2/PKD3 activity in MDA-MB-231 cells blocks MMP secretion, thereby attenuating their autocrine signaling that maintains the cells in a post-EMT state. Here, PKD2 is linked to neoplasm.