KDR and gastrointestinal stromal tumor: Besides the anti-angiogenic effect, we also demonstrated here that the dual inhibition of FGFR and VEGFR signaling potentiated proapoptotic and antiproliferative activities in GIST cells (Figure 5 and Figure 6, respectively) and resulted in the impressive synergy scores between BGJ 398 and sunitinib or regorafenib (Figure 7).