Anti-FGFR1 arrests ESCC tumor growth in vivo and attenuates the MAPK/ERK signaling pathway. (a) Antitumor effect of anti-FGFR1 treatment. Nude mice model established with TE-1 or EC9706 cells were treated orally with PD173074 at a dose of 50 or 100 mg/kg or with vehicle alone twice daily for 20 days. Data are presented as the mean ± SD; *P < 0.05, **P < 0.01, ***P < 0.001 significantly different compared to vehicle group. (b) The effect of anti-FGFR1 therapy on FGFR1, ERK, AKT, S6 and STAT1 phosphorylation detecting by western blotting.