SMAD3 and breast cancer: Similarly, the focal adhesion adaptor p130Cas (Crk-associated substrate, 130 kDa), which is overexpressed in breast cancer cells, promotes TGF-β1-induced EMT by binding to Smad3/TβRI, promoting the degradation of Smad3 and thereby suppressing the cytostatic activities of Smad3 [295,296].