TGFB1 and neoplasm: Inducing factors of EMT include activated intracellular EMT-related pathways (TGF-β/Smad, ERK, NF-κB, Wnt/β-Catenin, and Notch) in interaction with growth factors in the extracellular matrix (ECM) and receptors on the cell membrane surface, interaction between tumor cells and interstitial cells in the tumor environment, and an expression of EMT molecules induced by hypoxia in the tumor.