Figure 5. Apc deletion does not induce OIS within the intestine.

A–D. Small intestinal adenomas arising in Apc^Min/+ mice at 85 days. IHC showing high levels of β-catenin (A), p21 (B) and Ki67 (C) within adenomas. (D) Intestinal adenomas from Apc^Min/+ mice lack expression of senescence marker SA β-gal.

E. Apc deficient intestinal lesions that grow out from a non-stem cell ‘hit’ (1.0 mg/kg oral gavage), display high levels of β-catenin (E), with some expression of p21 (F) and high levels of proliferative markers Ki67 (G) and MCM2 (H).

I–L. Lgr5-EGFP⁺-Cre-ER Apc^fl/fl mice were treated with a single intraperitoneal injection of tamoxifen to induce recombination in the intestinal stem cell, resulting in intestinal adenoma formation at 24 days. Scale bars (A–H) represent 20 µm. (I) β-catenin IHC showing high levels of expression within intestinal adenomas.

J. p21 IHC showing upregulation in intestinal adenomas.

K and L IHC showing high levels of proliferation as illustrated by Ki67 (K) and MCM2 (L). Scale bars (I–L) represent 200 µm.