AKT1 and head and neck squamous cell carcinoma: Genomic alterations in one of the major components of the PI3K/AKT/mTOR pathway (e.g., PI3KCA, AKT1/2/3, and PTEN) were instead found in approximately 66% of HNSCC tumors and are also responsible for the development of resistance to the anti-EGFR therapy.