MTOR and cancer: PI3K/Akt/mTOR signaling was shown to regulate HIF-1α activation by hypoxia, as well as HIF1α-mediated resistance to hypoxia-induced apoptosis, in various human adult and pediatric cancers, including rhabdomyosarcoma and Ewing’s sarcomas [37], nasopharyngeal, colorectal, and glioma tumors [38].