Genotype | 9cRA | Animals-No | PIN | P | Tumors* No |
---|
 |  | at start | at end | Incidence | Frequency |  |  |
---|
p27+/+ | 0 | 20 | 15 | 13 | 0.13 ± 0.3 |  | 2 |
p27+/+ | + | 20 | 15 | 13 | 0.13 ± 0.3 | ns | 1 |
p27+/- | 0 | 20 | 10 | 40 | 0.7 ± 0.3 |  | 4 |
p27+/- | + | 20 | 10 | 60 | 1.3 ± 1.1 | ns | 3 |
p27-/- | 0 | 20 | 10 | 80 | 2.3 ± 1.2 |  | 5 |
p27-/- | + | 20 | 8 | 87 | 1.7 ± 1.0 | ns | 5 |
- Animals were implanted with a testosterone pellet at the age of 2 months and 6 days later MNU was injected ip to initiate the neoplastic process. Four days after carcinogen administration an estradiol pellet was sc implanted. %, incidence of tumors among control and treated animals; No: multiplicity of PIN per treated animal; ns, not significant (p > 0.05). To determine the incidence (%) and frequency of PIN in DLP, 4 μm thick longitudinally paraffin sections through the urethral part of the prostate were cut stepwise at three separate levels 30 μm apart.