AKT1 and head and neck squamous cell carcinoma: The phosphoinositide 3 kinase (PI3K), protein kinase B (Akt), and the mammalian target of rapamycin (mTOR) complex 1 (mTORC1) signaling pathways, which have been implicated in HNSCC progression14–16 and have been shown to be inhibited by metformin17.