Figure 2. Cell Death and Proliferation in Urethane-Induced Tumors.

(A): Immunohistochemistry for Ki-67 and pH 3 at 20 wk after urethane injection. (B): Mitotic index in the tumors of control and Cebpα^Δ/Δ mice (n = 7/group). Cebpα^Δ/Δ mice showed significantly higher numbers of Ki-67 positive cells in tumors (*p<0.01). The tumors in Cebpα^Δ/Δ mice were more proliferative than those in control mice. (C): Arrows indicate TUNEL stain and cleaved-caspase 3 positive cells in tumors. Apoptotic cells were not obvious in this model.