Since HGF/c-MET as well as PDGF/PDGFR systems have been recognised as important mediators of angiogenesis [10, 12, 52], it could not be excluded that the antiangiogenic mechanisms of TAS-115 in SS at least in partly encompassed targeting c-MET or PDGFRα. Here, PDGFRA is linked to synovial sarcoma.