RAF1 and squamous cell lung carcinoma: To investigate whether truncated RAF1 and BRAF could drive resistance to RTK inhibition also in other cell lines and tissues, Hs746T (gastric carcinoma, MET addicted), NCI-H1993 (non-small cell lung cancer, MET addicted), EBC1 (lung squamous cell carcinoma, MET addicted) and NCI-H508 (caecal adenocarcinoma, EGFR addicted), were transduced with truncated RAFs and GFP control vector.