Fig. 3.

Akt activation induces PIN. (A–D) Akt induced PIN in the VP. VP from both Wt (A) and MPAKT (Tg-Akt; B–D) mice were stained with hematoxylin/ eosin. Features of dysplasia indicative of PIN include loss of cell polarity (B–D), mitotic figures (blue arrows in B), nuclear atypia (black arrows in C), apoptotic bodies (light blue arrow in C), and intraepithelial lumen formation (white arrows in C and D). (E and F) Preservation of the basal cell layer in MPAKT VP. Tissue sections of VPs from Wt (E) and MPAKT (F) mice were stained with anti-p63. Arrows indicate representative p63-positive basal cells. (G and H) Concordance of Akt activation and PIN in the VP of PTEN heterozygous mice. Sequential tissue sections from the VP of PTEN heterozygous mice were stained with anti-PTEN (G) and anti-pS473 (H). Areas of positive anti-PTEN staining accompanied by negative anti-pS473 staining (filled arrows) whereas areas with loss of PTEN staining accompanied by positive anti-pS473 staining (open arrows) are indicated (compare G with H). (A–F, ×400; G and H, ×200; Insets, ×400.)