To examine whether the components of the FGF/FGFR signaling pathway become up-regulated at the transcriptional level in IM-resistant GISTs, we compared the mRNA expression of FGF-2 and FGFR1–3 in GIST T-1 vs. T-1R cells. The gene discussed is FGFR1; the disease is gastrointestinal stromal tumor.