The growth factors fibroblast growth factor (FGF), epidermal growth factor (EGF), hepatocyte growth factor (HGF), insulin-like growth factor (IGF), and neuregulin-1 (NRG) rescue oncogene addicted cancer cell lines from various TKIs, and growth factor rescue contributes to both intrinsic and acquired resistance2–4. The gene discussed is EGF; the disease is cancer.