marginally significantp = 0.045
As shown in Figure 5a , while the percentages of Ki67-positive cells were very similar between MMTV-ErbB2 mice and MMTV-ErbB2;E2f1 −/− mice, there was a marginally significant decrease in percentages of Ki67-positive cells in MMTV-ErbB2;Wap-Cre;E2f3 −/loxP mice than in ErbB2 mice (3.6% vs. 6.5%; p = 0.045).