Fig. 5: EPZ-regulated E3 ligases target AR and MYC stability.

a Comparison of genes that are differentially expressed by EPZ (n = 510) and known E3 Ubiquitin ligases. b mRNA expression of HERC3, HECTD4, MYCBP2, and TRIM49 in LNCaP treated with vehicle or 1 μM EPZ for 8 days. c AR and MYC protein levels in LNCaP cells 2 days after being transfected by Control, HERC3, HECTD4, MYCBP2, and TRIM49 targeting siRNA. Representative images shown. d AR and MYC protein levels in LNCaP cells treated with Vehicle or EPZ for 6 days followed by transfection of Control or HECTD4 and MYCBP2 targeting siRNA for 2 days. Representative images shown. e Viability of LNCaP cells treated with Vehicle or EPZ for 6 days followed by transfection of Control or HECTD4 and MYCBP2 targeting siRNA measured by CCK8 assay at day 12. f Co-immunoprecipitation assays performed with Flag-AR pulldown followed by western blot analysis in 293T cells transfected with Flag-AR and Halotag-HECTD4 constructs after 2 days. g Flag-AR pulldown followed by Ubiquitin western analysis in 293T cells transfected with both Flag-AR and HECTD4 constructs. h Co-immunoprecipitation assays performed with Flag-AR pulldown followed by western blot analysis in 293T cells transfected with Flag-AR and MYC-tag-MYCBP2 constructs after 2 days. Statistical tests: p value determined by Student’s t test (b, e). Error bars represent S.E.M. n = 3 independent experiments (b–e), n = 2 independent experiments (g, h). **p < 0.01; ***p < 0.001; ****p < 0.0001.