Fig. 3. Proliferation and caspase-3-mediated apoptosis as a function of genotype at 10 weeks of age. Each marker is shown at the top of the column to which it applies. Genotype of the mouse from which the gland was derived is shown to the left of the row to which it applies. Arrows highlight stained cells or regions of epithelium expressing the marker. (A) BrdU and Ki67 (inset) staining in wild type. (B) Cleaved caspase-3 staining showing rare apoptotic cells. (C) BrdU and Ki67 (inset) staining in an MMTV-SmoM2 gland. (D) Cleaved caspase-3 staining showing a rare apoptotic cell. (E,F) BrdU and cleaved caspase-3 staining, respectively, in a Ptch1/+ gland displaying the characteristic ductal phenotype.