SMAD2 and colonic neoplasm: TCM herbs such as ursolic acid (UA) treatment reduces the expression levels of TGF-β1 and the phosphorylation of Smad2/3 to block Zinc Finger E-Box Binding Homeobox 1 (ZEB1), further inducing the increased levels of miR-200c to reduce the invasive potential of colon cancer cells, suggesting that UA prevented colon cancer cell invasion through the TGF-β1/ZEB1/miR-200c signaling pathway (Zhang L. et al., 2019) (Table 2).