BRAF and small cell lung carcinoma: Additionally, different preclinical and clinical studies have shown that mutated tumors may cause resistance in several other ways, including small cell lung cancer (SCLC) transformation [39, 40], MET amplification [41, 42], HER2 amplification [42, 43], PIK3CA mutations [43], NRAS mutations and KRAS gain [44], BRAF mutations [45], and NF-κB activation [46].