In addition to creating tumor-derived ECM, CAFs have an impact on cancer cell proliferation, invasion, and metastasis through secretion of different growth factors [epidermal growth factor (EGF), FGF, hepatocyte growth factor (HGF), and insulin-like growth factor-1 (IGF-1) (2, 3, 31, 34, 41–, , 44)]. The gene discussed is HGF; the disease is cancer.