During the course of studying the functional consequences of PDGF ligand-specific β-PDGFR signaling in PCa, we discovered a novel function of PDGF-D for activation/shedding of the serine protease matriptase leading to cell invasion, migration, and tumorigenesis.
Down-regulation of platelet-derived growth factor-D expression blockades NF-κB pathway to inhibit cell proliferation and invasion as well as induce apoptosis in esophageal squamous cell carcinoma.
In this study, we found that PDGF-D-overexpressing PC3 cells (PC3 cells stably transfected with PDGF-D cDNA and referred to as PC3 PDGF-D) exhibited a rapid growth rate and enhanced cell invasion that was associated with the activation of mammalian target of rapamycin (mTOR) and reduced Akt activity.
Taken together, we conclude that the down-regulation of PDGF-D by novel approaches could lead to the down-regulation of Notch-1 and, in turn, inactivate NF-kappaB and its target genes (i.e., MMP-9 and VEGF), resulting in the inhibition of invasion and angiogenesis.