Lying FGFR2c-mediated EMT within the context of human keratinocytes [8,21]. The involvement of PKC was investigated taking advantage of your use of particular shRNA approaches, which showed that PKC depletion strongly impairs the improve of EMT signature, at the same time as the morphological alterations triggered by FGF2 in PANC-1 cells. Interestingly, only in these cells PKC phosphorylation/activation is appreciable, suggesting that PKC activation could possibly be dependent on FGFR2c expression price. Since PKCs are regarded “RAS-independent” signaling substrates activated by quite a few membrane receptors, which includes FGFRs [6], the identification of one of PKC family members as a pivotal signaling effector within the establishment of EMT phenotype (and possibly a larger aggressive behavior) could represent a fundamental advance towards new therapeutic methods aimed to bypass the “undruggable” targetCancers 2021, 13,17 ofRAS. Interestingly, we also found that PKC silencing abolished the capability of FGF2 to repress autophagy, a different vital procedure contributing to PDAC development and progression [2,14,15]. Bestatin MedChemExpress autophagy and EMT in cancer are linked in a complicated crosstalk [13], which we’ve got recently proposed to be regulated by FGFR2c and, to some extent, by its downstream PKC-mediated signaling, no less than during the early actions of human epidermal carcinogenesis [8,21,30]. In line with our earlier data, right here we highlighted a negative impact of PKC downstream FGFR2c on autophagy at least in the PANC-1 cell model, which very expresses the receptor. On the other hand, Trovafloxacin Epigenetic Reader Domain though autophagy is possibly repressed throughout the early phases of tumorigenesis, in sophisticated and aggressive cancers, for instance those from which PANC-1 and Mia PaCa-2 cell lines are derived, this process is enhanced, and it’s widely described as an oncogenic occasion sustaining cell survival and metabolism [15]. Similarly to what has been currently proposed in PDAC for MEK/ERK signaling in PDAC [14], our findings might be explained contemplating that a adverse regulation of autophagy (such as that exerted by FGR2c and by its PKC downstream signaling) truly leads to an oncogenic effect, because it can counteract tumor cell dependence on autophagy for survival. In this point of view, the particular repression of PKC not merely induces a reversion of EMT, but in addition increases autophagy, enhancing tumor cell dependence on this survival technique and consequently their susceptibility to autophagic inhibitors. Additionally, investigating in detail the molecular mechanisms underlying the inhibitory impact exerted by PKC on autophagy, we found that the depletion of PKC repressed the phosphorylation/activation on the autophagic inhibitor MTOR, visible only in PANC-1 cells in response to FGF2. The se results indicated that, as lately proposed in breast cancer [18], PKC could repress autophagy activating the canonical MTOR autophagy-related pathway also in PDAC. Additionally, PKC depletion strongly repressed ERK1/2 phosphorylation in both PDAC cell lines, even though MiaPaCa-2 cells appear to maintain a residual ERK1/2 phosphorylation, suggesting that the dependence of ERK1/2 signaling on PKC activation is consequent on FGFR2c expression levels. Furthermore, PKC depletion appeared ineffective on the phosphorylation of AKT, that is the canonical activator of MTOR, suggesting that, as previously proposed for cardiomyocytes [25], PKC could bypass AKT and directly activate MTOR by way of ERK1/2. Thinking about that ERK1/2 is also a well-known pathway regulating EMT.