PIK3CA and nasopharyngeal carcinoma: We modeled the development of acquired resistance in patients by treating PIK3CA mutant nasopharyngeal carcinoma cells (CNE2, HONE1) with increasing doses of BEZ235 for 6 to 9 months to select BEZ235-resistant sublines (CNE2/235, HONE1/235) (Supplementary Table S1).