MTOR and posterior cortical atrophy: Notably, AR signalling axis converges with RAS/MAPK and PI3K-Akt-mTOR to promote PCa development (Figure 2); in fact, AR signalling regulates cell growth, differentiation, and survival, thus playing a critical role as a transcriptional regulator in prostate tissue homeostasis and in PCa [69], while PI3K/Akt/mTOR and Ras/MAPK signalling favours epithelial–mesenchymal transition and cell migration/invasion [90].