AXL and small cell lung carcinoma: Within the respiratory system, the functions of Gas6/TAM in lung cancer have been extensively investigated.6, 34, 36, 81, 82 The two main types are SCLC and NSCLC.83 Wimmel et al.6 have shown that Axl is expressed in approximately 60% of NSCLC cell lines and in normal bronchial epithelial cells (NHBE) but not in SCLC cell lines.