Fig. 3

Histopathology results of H&E staining and β-catenin-immunostaining of dysplasias in the colon induced by DSS. A and B show dysplasia stained with H & E (Mouse ID; 02M11) induced in a male Polk^−/− mouse after DSS treatment. C to K show colorectal epithelium or dysplasias stained with β-catenin. The β-catenin is exclusively located on the cell membrane in normal colorectal epithelium (Fig. 3C). Some dysplasias induced in female Polk^−/− mice, where β-catenin is accumulated in the nucleus or cytoplasm, are shown in Figs. 3D (Mouse ID; 08F06), 3E (Mouse ID; 08F07), 3F (Mouse ID; 08F10), and 3G (Mouse ID; 08F10). All dysplasias examined in male Polk^+/+ and Polk^−/− mice show localization of β-catenin limited to the cell membrane, and representative images of are shown in Figs. 3H (Mouse ID; 02M08) and 3I (Mouse ID; 02M09) for Polk^+/+mice, and in Figs. 3J (Mouse ID; 06M11) and 3 K (Mouse ID; 06M12) for Polk^−/−mice. Figure 3B is enlarged magnification of the area surrounding the yellow frame in Fig. 3A. bar: 100 µm