SMAD3 and neoplasm: Interestingly, although SD-208 does not affect the growth of the primary tumor, it blocks the ability of both YAPS94A- and YAPS127A-mutated proteins to increase the number of lung metastases in mice models (Figures 4B, C), demonstrating the crucial role of TGF-β/Smad3 signaling pathway in YAP-driven lung metastasis development.