Figure 4

Histological features of cLys-Cox-2 x Apc ^Min/+ mouse colonic tumours stained with H&E. (A) cLys-Cox-2 x Apc ^Min/+ mouse colonic tumour demonstrating disorganised clusters of severely dysplastic epithelial cells. Size bar = 50 μm. (B) Non-transgenic Apc ^Min/+ mouse colonic tumour demonstrating typical features of low-grade dysplasia. Size bar = 50 μm. (C and D) Separate cLys-Cox-2 x Apc ^Min/+ mouse colonic tumours demonstrating invasion of neighbouring submucosa by dysplastic epithelial cells (arrows). (E) Patchy dysplastic epithelial cells staining for Cox-2 (arrows) in a cLys-Cox-2 x Apc ^Min/+ mouse colonic tumour (stromal Cox-2 score 4). Size bar = 50 μm. (F) Epithelial cell Cox-2 protein localization in cells at the base of a cLys-Cox-2 x Apc ^Min/+ mouse colonic tumour (arrows). Size bar = 50 μm. (G) Adjacent sections of a cLys-Cox-2 x Apc ^Min/+ mouse colonic tumour stained with either the Cayman (Cay) or Santa Cruz (SC) anti-Cox-2 antibody. Note prominent patchy epithelial cell staining (arrowheads) in addition to stromal cell staining (asterisk) in the same distribution in both panels. In general, adenomatous epithelial cell staining with the Santa Cruz antibody was consistently more widespread than with the Cayman antibody. Size bars = 50 μm. Immunohistochemistry for Cox-2 (using the Cayman antibody [H]) and lysozyme (J) on adjacent sections of a cLys-Cox-2 x Apc ^Min/+ mouse colonic tumour. Size bars = 50 μm. There was no correlation between Cox-2 and lysozyme immunoreactivity in individual adenomatous epithelial cells.