PIK3CA and squamous cell lung carcinoma: In a study of lung squamous cell carcinoma resistant to FGFR1 inhibitors, it was found that the FGFR1 inhibitor BGJ398 was combined with MEK inhibitor (trametinib) or PI3K inhibitor (BKM120) to overcome the BGJ398 single-drug resistance, and the results were consistent in the human-derived cell line, PDO, and PDX models (Huo et al., 2020).