In vitro activity: EPI-001 blocks transactivation of the AR NTD, interacts with the AF-1 region, inhibits protein-protein interactions with AR, and reduces AR interaction with androgen-response elements on target genes. In LNCaP cells, EPI-001 inhibits both androgen-dependent and androgen-independent (OCM-induced) cell proliferation. In LNCaP cells, EPI-001 also acts as a PPAR-gamma modulator to result in inhibition of androgen receptor expression and activity, which inhibits prostate cancer growth.

Cell Assay: LNCaP cells are treated with bicalutamide (BIC) or EPI-001 for 1 hr before the addition of R1881 (0.1 nM) for 4 days. LNCaP cells are treated with OCM (50%) with, or without, EPI-001 for 3 days (serum-free, androgen-free, phenol red-free conditions).