Figure 4.

(A) Western blotting to demonstrate the immediate molecular signalling changes induced in Apc^min/+ colon adenomas 4 h post single dosing with vehicle (1% Tween 80), gefitinib 75 mg kg⁻¹ o.d., AZ12253801 12.5 mg kg⁻¹ o.d. and combined gefitinib and AZ12253801. A volume of 30 μg pooled colon adenoma protein samples were loaded into wells in duplicate with a single positive control. Each loaded sample comprised equivalent amounts of protein (30 μg) from individual colon adenomas harvested from three male Apc^min/+ mice exposed to either vehicle, gefitinib, AZ12253801 or combined geftitinb and AZ12253801 for 4 h. A total of 19 colon adenomas were pooled from vehicle-treated mice, 26 colon adenomas from gefitinib-treated mice, 9 colon adenomas from AZ12253801-treated mice and 17 colon adenomas from combined-treated mice. Loading controls were either β actin or tubulin. (B–E) Densitometry readings for each phosphorylated protein were normalised relative to loading controls. Error bars indicate value ranges. Abbreviations: AZ12253801=IGF1R inhibitor; combo=combined EGFR/IGF1R inhibition; Gef=gefitinib; Veh=vehicle.