Celastrol targets AR-ERG-p536 in T/E fusion expressing PCa cells at protein level.

(A) Western blot shows that Celastrol 2 h treament can significantly target the p536 expression in VCaP cells. Celastrol concentrations are shown on the top of each lane. Short time treatment of Celastrol does not affect AR, AR3, ERG expression, and total p65, IKBα as well as other well known Celastrol targets such as total AKT, phosphorylated AKT-473 and Hsp90. (B) When Celastrol treatments last for 24 h, p536 signaling was almost abolished in all groups. In groups in which Celastrol concentration is equal or higher than 0.5 µM, significant decreased AR and ERG as well as AR3 expression were seen. When concentration reaches 2 µM, 24 h treatment can affect multiple signaling such as phospho-AKT. β-actin was used as the control.