title: Prazosin displays anticancer activity against human prostate cancers: targeting DNA and cell cycle.
abstract: Quinazoline-based alpha1-adrenoceptor antagonists, in particular doxazosin and terazosin, are suggested to display antineoplastic activity against prostate cancers. However, there are few studies elucidating the effect of prazosin. In this study, prazosin displayed antiproliferative activity superior to that of other alpha1-blockers, including doxazosin, terazosin, tamsulosin, and phentolamine. Prazosin induced G2 checkpoint arrest and subsequent apoptosis in prostate cancer PC-3, DU-145, and LNCaP cells. In p53-null PC-3 cells, prazosin induced an increase in DNA strand breaks and ATM/ATR checkpoint pathways, leading to the activation of downstream signaling cascades, including Cdc25c phosphorylation at Ser216, nuclear export of Cdc25c, and cyclin-dependent kinase (Cdk) 1 phosphorylation at Tyr15. The data, together with sustained elevated cyclin A levels (other than cyclin B1 levels), suggested that Cdk1 activity was inactivated by prazosin. Moreover, prazosin triggered mitochondria-mediated and caspase-executed apoptotic pathways in PC-3 cells. The oral administration of prazosin significantly reduced tumor mass in PC-3-derived cancer xenografts in nude mice. In summary, we suggest that prazosin is a potential antitumor agent that induces cell apoptosis through the induction of DNA damage stress, leading to Cdk1 inactivation and G2 checkpoint arrest. Subsequently, mitochondria-mediated caspase cascades are triggered to induce apoptosis in PC-3 cells.
authors.affiliation: School of Pharmacy, National Taiwan University, Taipei, Taiwan.
authors.forename: Ssu-Chia
authors.initials: SC
authors.lastname: Lin
authors.forename: Shih-Chieh
authors.initials: SC
authors.lastname: Chueh
authors.forename: Che-Jen
authors.initials: CJ
authors.lastname: Hsiao
authors.forename: Tsia-Kun
authors.initials: TK
authors.lastname: Li
authors.forename: Tzu-Hsuan
authors.initials: TH
authors.lastname: Chen
authors.forename: Cho-Hwa
authors.initials: CH
authors.lastname: Liao
authors.forename: Ping-Chiang
authors.initials: PC
authors.lastname: Lyu
authors.forename: Jih-Hwa
authors.initials: JH
authors.lastname: Guh
mesh_terms: D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D020169:Caspases / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D020552:Comet Assay; D004273:DNA, Neoplasm / Q000187:drug effects*; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008928:Mitochondria / Q000378:metabolism; D009374:Neoplasms, Experimental / Q000188:drug therapy; D011224:Prazosin / Q000494:pharmacology*; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays
chemical_list: D000317:Adrenergic alpha-Antagonists; D000970:Antineoplastic Agents; D004273:DNA, Neoplasm; D020169:Caspases; D011224:Prazosin