Figure 4. Obligatory tumor-specific retention of 1 p120 allele.

(A) TAM was administered to Apc^Min/+;Villin^CreERT2;p120^fl/fl mice, and mice were sacrificed at varying times after TAM as indicated in Table 2 (n = 3 mice per group). Representative immunofluorescent image showing p120 KO within adenoma tissue (white dashed boxes), as confirmed by maintained staining for β-catenin (second panel) and Kaiso (third panel). Scale bar: 50 μm. (B) Apc^Min/+ p120–KO tumors were costained for p120 (green) and apoptotic marker CC3 (red, n = 23 high-powered fields) or p-H3 (red, n = 19 high-powered fields). Analysis of p120-KO cells as compared with adjacent p120-positive tumor tissue indicates no change in apoptosis, yet a 2-fold increase in cell proliferation. Representative images are shown on the left. Scale bars: 100 μm. Quantification is shown at right. Error bars represent SEM. **P < 0.01, unpaired t test with Welch’s correction.