Fig. 2.

HGF overexpression imparts cetuximab resistance in CC cells. A Full-length human HGF was tagged with GFP at its carboxy terminus to engineer overexpression of HGF in cetuximab (CTX)-sensitive CC cells to generate HGF-overexpressing CC-HGF cells. B CC versus CC-HGF cells grown on plastic were lysed, resolved on SDS/PAGE, and immunoblotted for the indicated proteins. C CTX IC₅₀ determination in 3D: Two thousand CC and CC-HGF cells were seeded in type I collagen and incubated with indicated CTX concentrations for 14 days. Colony counts normalized to untreated controls are plotted from three individual experiments performed in triplicate. D Brightfield and fluorescent confocal images of CC and CC-HGF cell colonies imaged through their equatorial plane stained for DNA (DAPI, blue), HGF-GFP (GFP, green), and F-actin (Phalloidin, red). (Scale bars main panels: 100 μm; insets: 10 μm)