TY - JOUR
T1 - Multiple molecular pathways explain the anti-proliferative effect of valproic acid on prostate cancer cells in vitro and in vivo
AU - Shabbeer, Shabana
AU - Kortenhorst, Madeleine S.Q.
AU - Kachhap, Sushant
AU - Galloway, Nathan
AU - Rodriguez, Ron
AU - Carducci, Michael A.
PY - 2007/7/1
Y1 - 2007/7/1
N2 - BACKGROUND. Valproic acid (VPA), is a drug approved by the FDA for epilepsy and bipolar disorders. It is a known Histone Deacetylase Inhibitor (HDACI). We tested VPA, for its antiproliferative activity in prostate cancer (PCa) cell lines in vitro and in vivo. METHODS. DU-145 and PC-3 PCa cell lines were cultured with different doses of VPA. Cells were examined for their viability, cell cycle status and expression of cell cycle arrest, and proliferation markers. Nude mice bearing xenografts of human PCa cell lines, DU-145, and PC-3, were administered VPA in their drinking water. RESULTS. VPA displayed a dose- and time-dependent anti-proliferative effect on DU-145 and PC-3 PCa cell lines in vitro. A sustained effect of the drug was seen on cell cycle arrest even at 24 hr after removal of the drug, after which the effects returned to the basal state. Administration of 0.4% w/v VPA in drinking water (resulting in 0.4 mM VPA, in plasma) was effective in inducing growth arrest, cell death, and senescence in vivo and was also anti-angiogenic. The activation of all or some of these anti-proliferative pathways may be contingent on acetylation status of histones, confirmed by detection of increased acetyl-H3K9 in VPA-treated samples when compared with untreated controls. Pharmacodynamic studies showed an increase in expression of p21 and decrease in PCNA in xenografts of VPA-treated mice compared with protein expression in untreated controls. CONCLUSIONS. VPA may be functioning as an HDACI to inhibit growth of PCa cells in vitro and in vivo by modulating multiple pathways including cell cycle arrest, apoptosis, angiogenesis, and senescence.
AB - BACKGROUND. Valproic acid (VPA), is a drug approved by the FDA for epilepsy and bipolar disorders. It is a known Histone Deacetylase Inhibitor (HDACI). We tested VPA, for its antiproliferative activity in prostate cancer (PCa) cell lines in vitro and in vivo. METHODS. DU-145 and PC-3 PCa cell lines were cultured with different doses of VPA. Cells were examined for their viability, cell cycle status and expression of cell cycle arrest, and proliferation markers. Nude mice bearing xenografts of human PCa cell lines, DU-145, and PC-3, were administered VPA in their drinking water. RESULTS. VPA displayed a dose- and time-dependent anti-proliferative effect on DU-145 and PC-3 PCa cell lines in vitro. A sustained effect of the drug was seen on cell cycle arrest even at 24 hr after removal of the drug, after which the effects returned to the basal state. Administration of 0.4% w/v VPA in drinking water (resulting in 0.4 mM VPA, in plasma) was effective in inducing growth arrest, cell death, and senescence in vivo and was also anti-angiogenic. The activation of all or some of these anti-proliferative pathways may be contingent on acetylation status of histones, confirmed by detection of increased acetyl-H3K9 in VPA-treated samples when compared with untreated controls. Pharmacodynamic studies showed an increase in expression of p21 and decrease in PCNA in xenografts of VPA-treated mice compared with protein expression in untreated controls. CONCLUSIONS. VPA may be functioning as an HDACI to inhibit growth of PCa cells in vitro and in vivo by modulating multiple pathways including cell cycle arrest, apoptosis, angiogenesis, and senescence.
KW - Angiogenesis
KW - Histone deacetylase inhibitor
KW - Prostate cancer
KW - Senescence
KW - Valproic acid
UR - http://www.scopus.com/inward/record.url?scp=34250872780&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34250872780&partnerID=8YFLogxK
U2 - 10.1002/pros.20587
DO - 10.1002/pros.20587
M3 - Article
C2 - 17477369
AN - SCOPUS:34250872780
SN - 0270-4137
VL - 67
SP - 1099
EP - 1110
JO - Prostate
JF - Prostate
IS - 10
ER -