Figure 3

p-AKT and p-FOXO1 signaling feature prominently in normal retina and ΔPTEN-driven retinoblastomas. A-C. Mouse eyes from control, Chx10-cre; Rb1 ^fl/fl ; p107 ^−/−, or Chx10-cre; Rb1 ^fl/fl ; p107 ^−/− ; Pten ^fl/fl were harvested at 3 (A), 7 (B), and 30 (C) days after birth, fixed, embedded in paraffin wax, and sectioned for H&E staining or IHC analysis using specific antibodies for Ki-67, caspase-3, p-AKT (Ser473), or p-FOXO1 (Ser256). Scale bar, 20 μm. D. TUNEL staining in the retina of the listed mouse genotypes. E. Mouse eyes of Chx10-cre; Rb1 ^fl/fl ; p107 ^−/− ; Pten ^fl/fl (TKO) were harvested at 3, 15, and 30 days after birth, fixed, embedded in paraffin wax, and sectioned for caspase-3 IHC analysis. Scale bar, 100 μm. F. Quantification of TUNEL-positive Cre:GFP (+) sorted cells from these mice (n = 3). G. Quantification of TUNEL positive Cre:GFP (−) sorted cells from these mice (n = 3). Data are mean from samples analyzed in triplicate, and error bars represent standard deviation.