Structure−Activity Relationships in 1,4-Benzodioxan-Related Compounds. 8. {2-[2-(4-Chlorobenzyloxy)phenoxy]ethyl}-[2-(2,6-dimethoxyphenoxy)ethyl]amine (Clopenphendioxan) as a Tool to Highlight the Involvement of α<sub>1D</sub>- and α<sub>1B</sub>-Adrenoreceptor Subtypes in the Regulation of Human PC-3 Prostate Cancer Cell Apoptosis and Proliferation
作者:Wilma Quaglia、Giorgio Santoni、Maria Pigini、Alessandro Piergentili、Francesco Gentili、Michela Buccioni、Michela Mosca、Roberta Lucciarini、Consuelo Amantini、Massimo Ivan Nabissi、Patrizia Ballarini、Elena Poggesi、Amedeo Leonardi、Mario Giannella
DOI:10.1021/jm0580398
日期:2005.12.1
A series of new alpha(1)-adrenoreceptor antagonists (5-18) was prepared by introducing various substituents (Topliss approach) into the ortho, meta, and para positions of the benzyloxy function of the phendioxan open analogue 4 ("openphendioxan"). All the compounds synthesized were potent antagonists and generally displayed, similarly to 4, the highest affinity values at alpha(1D)-with respect to alpha(1A)- and alpha(1B)-AR subtypes and 5-HT1A subtype. By sulforhodamine B (SRB) assay on human PC-3 prostate cancer cells, the new compounds showed antitumor activity (estimated on the basis of three parameters GI(50), TGI, LC50), at low micromolar concentration, with 7 ("clopenphendioxan") exhibiting the highest efficacy. Moreover, this study highlighted for the first time alpha(1D)- and alpha(1B)-AR expression in PC3 cells and also demonstrated the involvement of these subtypes in the modulation of apoptosis and cell proliferation. A significant reduction of alpha(1D)- and alpha(1B)-AR expression in PC3 cells was associated with the apoptosis induced by 7. This depletion was completely reversed by norepinephrine.