CASP3 and gastrointestinal stromal tumor: In contrast to GIST T-1R cells, GIST 430 cells were not sensitive for combination of the FGFR and VEGFR inhibitors, which was evidenced by proliferation activity and crystal violet staining (Supplementary Figure S3A–D) and absence of apoptotic markers (i.e., cleaved forms of PARP and caspase-3, as shown in Supplementary Figure S3E), no synergy or even additive effects between BGJ 398 and sunitinib or regorafenib were found for GIST 430 cells (Supplementary Figure S4 and Table 2).