PIK3CA and head and neck squamous cell carcinoma: As targeted inhibition of mTORC2 has been explored infrequently to date, we have generated a novel gene knockout model of RICTOR using CRISPR/Cas9 to determine how loss of RICTOR/mTORC2 activity affects the therapeutic response of HNSCC tumor cells to PI3K inhibition, as well as to EGFR inhibition and cisplatin treatment.