FGFR1 and neoplasm: With regards to ligand-dependent signaling, it has been shown that FGFR1-amplified tumor cells require FGF ligands for signaling and growth, and that overexpression of FGFs or coexpression of both FGFs and FGFRs occur in non small cell lung cancer (NSCLC), head and neck squamous cell carcinomas (HNSCC), and in basal-like breast cancer cells [4–7].