Figure 6. PUMA mediates the anti-tumor effect of UCN-01 in a xenograft model.

A. Nude mice were injected s.c. with 4×10⁶ p21-KO or p21-KO/PUMA-KO HCT116 cells. After one week, mice were treated with 9 mg/kg of UCN-01 or the control sodium citrate buffer by i.p. injection for 5 consecutive days. Left: Tumor volume was calculated and plotted. Right: Representative tumors at the end of experiment. B. Paraffin-embedded tumor sections were stained for p-AKT and p-FoxO3a according to Materials and Methods. C. PUMA expression in representative tumors with or without UCN-01 treatment was analyzed by Western blotting. D. Left: Following staining tumor sections for TUNEL according to Materials and Methods, TUNEL-positive cells were counted and plotted. Right: Tumor sections were stained for active caspase 3 according to Materials and Methods. Active caspase 3-positive cells were counted and plotted.