Figure 8.
Decreased incidence and growth rate of urethane-induced lung tumors in p27S10A mice. (A) Total number of lung tumors in wild-type, p27+/–, p27–/–, and p27S10A mice 20 wk following a single dose of urethane. Lungs were dissected and macroscopic tumors were counted by visual inspection. The results were analyzed using a one-way analysis of variance with the Tukey-Kramer multiple comparison test. (***) p < 0.001; (**) p < 0.01; (*) p < 0.05. (B) p27S10A protein levels in the lung are similar to p27 levels in p27+/– mice. Lung extracts from wild-type (WT), p27+/–, p27–/–, p27S10A/S10A (S10A), and p27CK–/CK– (CK–) mice were resolved on SDS-PAGE, and the membrane was probed with a polyclonal p27 (C19) antibody, stripped, and reprobed with a monoclonal Grb2 antibody to evaluate protein loading. (C,D) Lung tumors were counted according to their size: small tumors (between 0 and 2 mm in diameter) (C), and large tumors (between 2 and 4 mm in diameter) (D). Statistical analyses were performed as in A. (E) Representative lungs for each mouse genotype following dissection. Tumors are indicated by arrows.