Figure 1. Prostate-specific deletions of Tsc1, Foxp3, and c-Myc and tumor progression in mouse prostate.

A. Efficient deletions of the Foxp3 and Tsc1 loci in the PB-Cre⁴⁺Foxp3^flox/yTsc1^flox/flox (Foxp3/Tsc1 double cKO), but not the PB-Cre⁴⁺ transgenic control mice, at 12 weeks of age (p value by a two-tailed t test). Data shown are means and standard deviation (SD) of the ratio of product A/product B for Foxp3 or product C/product D for Tsc1 of DNA isolated from the micro-dissected prostate epithelium. B. Targeted deletions of the Foxp3 and Tsc1 loci caused by the reduction of Foxp3 and Tsc1 transcripts in prostate tissue (p value by a Mann-Whitney U test). The RNAs isolated from micro-dissected prostate epithelia were quantitated by real-time PCR. C. Tumor development and cell proliferation in the dorsal and lateral lobes of the prostates in Foxp3/Tsc1 double-cKO mice compared with that in Tsc1 single-cKO, Foxp3 single-cKO, and PB-Cre4⁺ control mice at 22 weeks of age under a C57BL/6 genetic background, identified by H&E and Ki67 staining. D. The percentage of Ki67+ cells as an indicator of proliferating cells among the mouse prostate or tumor tissues. For each mouse, at least five 40x fields were counted. Data are presented as means ± SD. * p < 0.05 by one-way ANOVA followed by protected least-significant difference test vs. PB-Cre⁴ control mice. E. H&E, CK5, and p63 staining in the dorsal and lateral lobes of the prostates in Foxp3/Tsc1 double-cKO mice compared with that in Tsc1 single-cKO, Foxp3 single-cKO, and PB-Cre4⁺ control mice at 43 weeks of age. F. Immunostaining for androgen receptor (AR), pS6^S235/236, p4EBP1^T37/46, c-MYC, and CK5/CK8 in the prostates of PB-Cre⁴ control, Foxp3 cKO, Tesc1 cKO, Foxp3/Tsc1 double cKO, and Foxp3/Tsc1/c-Myc triple cKO mice at 12 weeks of age. G. Weights of prostates in the mice at 12 weeks of age. Data are presented as the means and SD of the prostate weights. * p < 0.05, two-tailed t test vs. PB-Cre⁴ control mice. H and I. Kaplan–Meier curves of mPIN and cancer incidences in cKO and PB-Cre⁴ control mice (n = 40/group). At 7, 12, 17, 22, 27, 32, 37, and 43 weeks of age, 5 mice/per time point were sacrificed for pathologic analysis. Arrows indicate time points of animal sacrifice. * p < 0.05, log-rank test vs. PB-Cre⁴ control mice. cKO, prostate conditional knockout. All experiments were repeated two times.