Dual silencing of Hsp27 and c-FLIP enhances doxazosin-induced apoptosis in PC-3 prostate cancer cells.

Abstract

We evaluated effect of dual gene silencing of Hsp27 and c-FLIP in doxazosin-induced apoptosis of PC-3 cell. After transfection using Hsp27 and c-FLIP siRNA mixture (dual silencing), doxazosin treatment was done at the concentrations of 1, 10, and 25  μ M. We checked apoptosis of PC-3 cells with and TUNEL staining. We also checked interaction between Hsp27 and C-FLIP in the process of apoptosis inhibition. Spontaneous apoptotic index was 5% under single gene silencing of Hsp27 and c-FLIP and 7% under dual silencing of Hsp27 and c-FLIP. When doxazosin treatment was added, apoptotic indices increased in a dose-dependent manner (1, 10, and 25  μ M): nonsilencing 10, 27, and 52%; Hsp27-silencing: 14, 35, and 68%; c-FLIP silencing: 21, 46, and 78%; dual silencing: 38, 76, and 92%. While c-FLIP gene expression decreased in Hsp27- silenced cells, Hsp27 gene expression showed markedly decreased pattern in the cells of c-FLIP silencing. The knockout of c-FLIP and Hsp27 genes together enhances apoptosis even under 1  μ M, rather than low concentration, of doxazosin in PC-3 cells. This finding suggests a new strategy of multiple knockout of antiapoptotic and survival factors in the treatment of late-stage prostate cancer refractory to conventional therapy.

• Authors: Sang Soo Kim, Hee-Ju Cho, Jeong-Man Cho, Jung Yoon Kang, Hyun-Won Yang, Tag Keun Yoo
• Journal: TheScientificWorldJournal (ScientificWorldJournal) Vol. 2013 Pg. 174392 ( 2013) ISSN: 1537-744X [Electronic] United States
• PMID: 23853530 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents
• CASP8 and FADD-Like Apoptosis Regulating Protein
• CFLAR protein, human
• HSP27 Heat-Shock Proteins
• Doxazosin

Topics

• Antineoplastic Agents (administration & dosage)
• Apoptosis (drug effects)
• CASP8 and FADD-Like Apoptosis Regulating Protein (genetics)
• Cell Line, Tumor
• Doxazosin (administration & dosage)
• Drug Synergism
• Gene Silencing
• Genetic Therapy (methods)
• HSP27 Heat-Shock Proteins (genetics)
• Humans
• Male
• Prostatic Neoplasms (drug therapy, genetics, pathology)
• Treatment Outcome