Triptolide Inhibits PCa Cells Proliferation Figure 5. Triptolide down-regulated AR expression in LNCaP cells. (A) Triptolide decreased AR mRNA level in LNCaP cells in a dose- dependent manner. LNCaP cells were treated with indicated doses of Triptolide for 24 h before analysis. qRT-PCR was performed using the specific primers for AR and b-actin. (B) Triptolide decreased AR mRNA level in LNCaP cells in a time-dependent manner. LNCaP cells were treated with 0.1 mM Triptolide for indicated times before analysis. (C) Triptolide and Celastrol decreased AR protein level in LNCaP cells in a dose-dependent manner. LNCaP cells were treated with indicated doses of Triptolide or Celastrol for 24 h before Western blot analysis. a-tubulin was used as a loading control. (D) Triptolide decreased AR protein level in LNCaP cells in a time-dependent manner. LNCaP cells were treated with 0.1 mM Triptolide for indicated times before Western blot analysis. a-tubulin was used as a loading control. (E) Triptolide decreased AR target genes expression in LNCaP cells. LNCaP PLoS ONE | www.plosone.org 9 May 2012 | Volume 7 | Issue 5 | e37693