Fig. 1

Afatinib demonstrates greater anti-tumor activity than other generation EGFR-TKIs or mAbs in ESCC. a Six ESCC cell lines were treated with afatinib at the indicated concentrations (from 0 to 10 μM) for 72 h. Cell viability relative to vehicle-treated controls is shown (means ± SDs; three independent assays). b Tumor growth curves show the in vivo assessment of afatinib-sensitive KYSE450 and afatinib-insensitive KYSE510 cells treated with vehicle control or afatinib (15 mg/kg/day, oral gavage, n = 5) for 21 days. c The efficacy of afatinib was further explored in another five PDXs for 21 days treatment (15 mg/kg/day, oral gavage, n = 5). Tumor growth curves and corresponding TGI are shown here. Data are presented as means ± SDs. P values were calculated using one-way ANOVA or unpaired two-tailed t tests. **P < 0.01; ***P < 0.001; ****P < 0.0001; ns = not significant