Lying FGFR2c-mediated EMT inside the context of human keratinocytes [8,21]. The involvement of PKC was investigated taking advantage of your use of precise shRNA approaches, which showed that PKC depletion strongly impairs the boost of EMT signature, at the same time as the morphological changes triggered by FGF2 in PANC-1 cells. Interestingly, only in these cells PKC phosphorylation/activation is appreciable, suggesting that PKC activation might be dependent on FGFR2c expression rate. Due to the fact PKCs are regarded as “RAS-independent” signaling substrates activated by various membrane receptors, which includes FGFRs [6], the identification of certainly one of PKC loved ones members as a pivotal signaling effector inside the establishment of EMT phenotype (and possibly a higher aggressive behavior) could represent a basic advance towards new therapeutic techniques aimed to bypass the “undruggable” targetCancers 2021, 13,17 ofRAS. Interestingly, we also identified that PKC silencing abolished the ability of FGF2 to repress autophagy, a further critical method contributing to PDAC development and progression [2,14,15]. Autophagy and EMT in cancer are linked inside a complicated crosstalk [13], which we’ve got lately proposed to be regulated by FGFR2c and, to some extent, by its downstream PKC-mediated signaling, at the very least throughout the early actions of human epidermal carcinogenesis [8,21,30]. In line with our earlier information, here we highlighted a negative effect of PKC downstream FGFR2c on autophagy at least in the PANC-1 cell model, which extremely expresses the receptor. Nonetheless, although autophagy is possibly repressed during the early phases of tumorigenesis, in sophisticated and aggressive cancers, such as these from which PANC-1 and Mia PaCa-2 cell lines are derived, this approach is 1-Methyladenosine Endogenous Metabolite enhanced, and it’s extensively described as an oncogenic occasion Tetrahydrocortisol supplier sustaining cell survival and metabolism [15]. Similarly to what has been already proposed in PDAC for MEK/ERK signaling in PDAC [14], our findings could be explained taking into consideration that a damaging regulation of autophagy (like that exerted by FGR2c and by its PKC downstream signaling) in fact leads to an oncogenic impact, because it can counteract tumor cell dependence on autophagy for survival. Within this point of view, the certain repression of PKC not simply induces a reversion of EMT, but additionally increases autophagy, enhancing tumor cell dependence on this survival tactic and consequently their susceptibility to autophagic inhibitors. Additionally, investigating in detail the molecular mechanisms underlying the inhibitory impact exerted by PKC on autophagy, we discovered that the depletion of PKC repressed the phosphorylation/activation in the autophagic inhibitor MTOR, visible only in PANC-1 cells in response to FGF2. The se outcomes indicated that, as not too long ago proposed in breast cancer [18], PKC could repress autophagy activating the canonical MTOR autophagy-related pathway also in PDAC. Furthermore, PKC depletion strongly repressed ERK1/2 phosphorylation in each PDAC cell lines, even when MiaPaCa-2 cells seem to retain a residual ERK1/2 phosphorylation, suggesting that the dependence of ERK1/2 signaling on PKC activation is consequent on FGFR2c expression levels. Moreover, PKC depletion appeared ineffective around the phosphorylation of AKT, which is the canonical activator of MTOR, suggesting that, as previously proposed for cardiomyocytes [25], PKC could bypass AKT and straight activate MTOR through ERK1/2. Taking into consideration that ERK1/2 can also be a well-known pathway regulating EMT.