MEC proliferation and survival rates are not altered in Cdc42-overexpressing mammary glands. (A) Representative images of pHH3 immunostaining on tissue sections from line 4 and control mammary glands treated for 1 week with dox. Scale bar = 50 μm. Graph shows average percentage of pHH3-positive cells ± SEM in TEBs after 1 week and 3 weeks of dox treatment (n = 3,3;3,4, P = 0.43;0.77). (B) Representative images of CC3 immunostaining on tissue sections from line 4 and control mammary glands treated for 1 week with dox. Scale bar = 50 μm. Graph depicts average percentage of CC3-positive cells ± SEM in TEBs after 1 week and 3 weeks of dox treatment in vivo (n = 5,5;3,4 P = 0.53;0.59). (C) Histograms represent flow cytometry analysis of isolated primary control and Cdc42-OE MECs stained with propidium iodide (PI) after 1 week of dox treatment in vivo. Table shows the percentage of cells in each phase of the cell cycle out of total live cells (≥67,000 events) demonstrating that control and Cdc42 OE MECs have similar cell cycle profiles. Data are representative of two independent experiments (n = 5 mice per genotype). CC3, cleaved caspase-3; Cdc42, cell division cycle 42; MEC, mammary epithelial cell; OE, overexpressing; pHH3, phosphorylated histone-H3; TEB, terminal end bud.