FGFR2 and gastric cancer: A growth inhibitory assay showed that the IC50 values of the FGFR inhibitor PD173074 in FGFR2-amplified cells were 0.01–0.07 μM, whereas those in non-amplified cells were 2.6–13.2 μM, indicating that FGFR2 amplification conferred an approximately 100-fold hypersensitivity to FGFR inhibitor in gastric cancer cell lines (Figure 1C).