Fig. 5. The stabilization of p53^R270H mutant protein during tumor progression from hyperplasia to carcinoma in AKP^270/+ mice.

Immunohistochemical staining of p53 in a representative hyperplastic polyp (HP, b left panel), an adenoma (b right panel) and three carcinomas (c) arising in the cecum of AKP^270/+ mice. A section from the cecum of a wild-type mouse was used as a control (a). The p53 staining ranges from non-detectable staining in the normal (a) and HP (b) sections, to weak staining (<10% positivity) in the adenoma (b) and carcinoma 1(c left panel), and to strong staining in carcinomas 2 and 3 (>10% positivity). The dashed lines indicate the muscularis mucosae. Black arrows indicate the invasive glands with weak p53 staining; red arrows indicate the invasive gland with strong p53 staining. Scale bars: 50 μm.