AXL and chronic myelogenous leukemia, BCR-ABL1 positive: Axl, a proto-oncogene, was originally isolated from chronic myelogenous leukemia [8] and has been reported to be critical for survival, metastasis, angiogenesis, epithelial-to-mesenchymal transition, and drug resistance in many cancer cells, including NSCLC [5,10,16,18].