Fig. 6

Loss of p53 enhances hyperplasia in MMTV-Spy1 mice. a Immunohistochemical analysis for p53 expression in inguinal mammary glands and tumours of DMBA-treated MMTV-Spy1 mice and littermate controls. Representative images are shown in the left panel. Levels of p53 were quantified using ImageJ analysis (right panel). Scale bar = 100 μm. b Fat pads of wild-type mice were reconstituted with mammary epithelial cells from MMTV-Spy1 mice crossed with p53 null mice and were monitored for HANs and formation of tumours. Only tumour-negative mice were screened for the formation of HANs (wild-type n = 5; MMTV-Spy1 n = 7, p53+/− n = 13; p53−/− n = 6; MMTV-Spy1 p53+/− n = 12; MMTV-Spy1 p53−/− n = 5). c Representative images of whole mounts. Scale bar = 0.1 mm. Error bars represent SE; Student’s T test (a) and Mann-Whitney (b). *p < 0.05, **p < 0.01, ***p < 0.001