Figure 1.

Effect of conditional knockout of Egfr on duodenal tumor burden in Lrig1 null mice. (A) Comparison of tumor burden of duodenal tumors from Lrig1^Cre/Cre;Egfr^flox/flox;R26R^YFP mice treated with TAM or corn oil (CTL). Red line over the box-plot of TAM group indicates median value when mice without tumors were excluded. (B) Histology of duodenal tumors that develop in the TAM and CTL groups. (C) Greyscale Egfr^Em fluorescence (anti-GFP staining) and Lrig1^Ap fluorescence in spontaneous duodenal tumors from Lrig1^Ap/Ap;Egfr^Em/+ mice. Arrows and arrowheads indicate Egfr^Em/Lrig1^Ap-positive tumor cells and Egfr^Em-positive and Lrig1^Ap-negative stroma, respectively. (D) Greyscale immunofluorescence for β-catenin. Left: duodenal tumor from Lrig1^Cre/+;Apc^flox/+ mouse. Center and right: duodenal tumor from Lrig1^Cre/Cre;Egfr^flox/flox;R26^YFP treated with corn oil (center) and TAM (right), respectively. Scale bar = 100 μm. CTL, control.