Pharmacological Exploitation of the Peroxisome Proliferator-Activated Receptor γ Agonist Ciglitazone To Develop a Novel Class of Androgen Receptor-Ablative Agents
作者:Jian Yang、Shuo Wei、Da-Sheng Wang、Yu-Chieh Wang、Samuel K. Kulp、Ching-Shih Chen
DOI:10.1021/jm701212m
日期:2008.4.1
On the basis of our finding that the peroxisome proliferator-activated receptor gamma (PPAR gamma) agonist ciglitazone at high doses was able to mediate PPAR gamma-independent transcriptional repression of androgen receptor (AR) in a tumor cell-specific manner, we used Delta 2CG, a PPAR gamma-inactive analogue of ciglitazone, to conduct lead optimization to develop a novel class of AR-ablative agents. Structure-activity analysis indicates a high degree of flexibility in realigning Delta 2CG's structural moieties without compromising potency in AR repression, as evidenced by the higher AR-ablative activity of the permuted isomer 9 [(Z)-5-(4-hydroxybenzylidene)3-(1-methylcyclohexylmethyl)thiazolidine-2,4-dione]. Further modificiations of 9 gave rise to 12 [(Z)-5-(4-hydroxy-3-trifluoromethylbenzylidene)-3-(1-methylcyclohexylmethyl)thiazolidine-2,4-dione], which completely inhibited AR expression in LNCaP cells at low micromolar concentrations. This AR down-regulation led to growth inhibition in LNCaP cells through apoptosis induction. Moreover, the role of AR repression in the antiproliferative effect of compound 12 was validated by the differential inhibition of cell viability between androgen-responsive and androgen-nonresponsive cells.