Soluble growth factors including transforming growth factor-beta (TGF-β), epidermal growth factor (EGF), fibroblast growth factor (FGF), hepatocyte growth factor (HGF) secreted by stromal cells such as cancer-associated fibroblast, tumor-associated macrophage and neutrophil play a critical role in activating EMT in cancer cells (18). The gene discussed is HGF; the disease is cancer.