FGFR1 and gastrointestinal stromal tumor: Given that phospho-FGFR2α was the major phospho-RTK overexpressed in GIST T-1R cells, we examined whether BGJ398 (selective inhibitor for FGFR1/2/3) is able to reduce viability in IM-sensitive vs. resistant GIST T-1 cells and enhance the cytotoxic effect of IM.