Figure 2.

Overview of PI3K/Akt/mTOR activity regulation, downstream effectors and target inhibitors. This pathway is commonly upregulated in tumor cells by upstream stimulation, activating genetic alterations in PI3K, Akt, mTOR, loss of function of PTEN or activation via cross-talk pathways. Specific inhibitors of PI3K, Akt and mTOR may represent a potential and innovative strategy in tumors with overactivation of this pathway. PI3K, phosphatidylinositol-4,5-bisphosphate 3-kinase; mTOR, mammalian target of rapamycin; EGF, epidermal growth factor; VEGF, vascular endothelial growth factor; IGF-1, insulin-like growth factors-1.