Fig. 3. Second-generation EGFR-TKI is effective in cetuximab-resistant FaDuCR cells.

a FaDuCR cells were treated with 100 nM afatinib for up to 48 h and probed for the indicated proteins. b FaDuCR cells were treated with 10 ng mL⁻¹ cetuximab, 100 nM afatinib, 100 nM dacomitinib, or vehicle control for 5 d. Cell viability was evaluated using the CellTiter-Glo assay and is shown relative to untreated control cells (mean ± SD of six independent experiments). c, d In a mouse FaDuCR xenograft model, tumors were treated with cetuximab 40 mg kg⁻¹ twice weekly, dacomitinib 15 mg kg⁻¹, or vehicle. Each group consisted of 10 mice. Data are mean ± SEM. Tumor growth curves (c) and survival curves for tumor-bearing mice in each group (d) are shown. *P < 0.05