Bexlosteride (LY300502), a benzoquinolinone derivative, functions as a human type I 5α-reductase inhibitor. It demonstrates metabolic inhibition, antiproliferative, and antisecretory activities specifically in LNCaP human prostatic adenocarcinoma cell cultures, positioning it as a potent agent for prostate cancer research [1] [2].

Bexlosteride inhibits reductive metabolism of [ 3 H-T] in a concentration-dependent manner in the LNCaP cells, with an IC 50 of 5.77 nM [1]. Bexlosteride significantly antagonizes Testosterone-induced stimulation of LNCaP cellular proliferation at concentrations greater than 10 nM, and completely blocks the mitogenic effects of Testosterone on LNCaP cells at 1000 nM[1]. Bexlosteride significantly antagonizes Testosterone -induced PSA secretion at a concentration equal to or greater than 30 nM [1].