Fig. 4

Elevated Spy1 increases mammary tumour formation. (a) Primary mammary epithelial cells from MMTV-Spy1 and p53 null intercrossed mice were injected into the cleared fat pads of wildtype mice and monitored weekly for HANs and tumour development. HANs were only quantified in tumour negative mice (Cntl n = 15, MMTV-Spy1 n = 17, p53+/- n = 21, p53-/- n = 14, MMTV-Spy1 p53+/- n = 21, MMTV-Spy1 p53-/- n = 13). Immunohistochemical analysis of (b) phospho histone H3 and (c) cleaved caspase 3 in Spy1 p53 null and p53 null tumours (p53 null n = 3; Spy1 p53 null n = 4). Quantification of percent positive (b) phospho histone H3 or (c) cleaved caspase 3 depicted graphically. Scale bar = 100 μm; Mann-Whitney (a) and Student’s T-test (b&c). *p < 0.05, **p < 0.01, ***p < 0.001