Fig. 2: Pin1 inhibitors block the transcriptional activity of AR.

a, b Inhibitory dose–response curves for juglone, ATRA, and 13cisRA on the activity of PSA(6.1 kb)- and PB-luciferase in LNCaP cells stimulated with R1881 (1 nM) for 24 h. Data shown are normalized to the induction by R1881, which was 149-fold for PSA (6.1 kb)- and 1420-fold for PB-luciferase, n = 4 independent experiments. (c, d) Activities of CMV and AP-1 reporters after incubating with juglone (20 µM), 13cisRA (10 µM), ATRA (10 µM), or vehicle (DMSO) for 24 h. Data shown represent the means ± s.e.m. from four independent experiments. e Western blot analysis of PSA, AR, and Pin1 protein levels from LNCaP cells treated with juglone (20 µM) or ATRA (10 µM), and 1 nM of R1881 or vehicle for 24 h. f Graph showing the quantified PSA levels after normalizing to β-actin. g Representative fluorescence micrographs showing the localization of YFP-AR in LNCaP cells pre-treated with the indicated compounds and stimulated with R1881 (1 nM) or vehicle (EtOH) for 2 h. The scale bar represents 20 μm. h YFP-AR localization was quantified by calculating the ratio of average YFP intensity in the nucleus compared to the cytosol. Scores greater than 1 indicate nuclear localization. At least 50 cells were scored for each treatment. Data shown are the normalized means ± s.e.m. from three independent experiments. Statistical significance was determined by one-way ANOVA using Holm-Sidak’s multiple comparisons test. ***P < 0.001; ns not significant.