MTOR and cancer: The PI3K/Akt/mTOR (PI3K: phosphoinositide 3-kinase, Akt: serine/threonine kinase 1, and mTOR: mammalian target of rapamycin) signaling pathway has attracted high attention for cancer treatment owing to its role in the differentiation, proliferation, invasion, and migration of cancer cells [115,116,117].