Supplemental Figure 3 from SMAD4 Loss Is Associated with Cetuximab Resistance and Induction of MAPK/JNK Activation in Head and Neck Cancer Cells

(A) Western blot confirming the knockdown of SMAD4 levels by stable expression of short-hairpin RNA in SCC25 cell line. (SC: scrambled control shRNA, SMAD4KD: shRNA against SMAD4). (B) Matrigel colony formation assay was performed for SCC25 cell line (controls and SMAD4 knock-downs) treated with PBS, 100nM or 1000nM cetuximab. (C) Western blot showing MAPK and JNK activity in SMAD4-depleted or control SCC25 cells.