Guggulsterone-induced apoptosis in human prostate cancer cells is caused by reactive oxygen intermediate dependent activation of c-Jun NH2-terminal kinase.
Guggulsterone, a constituent of Indian Ayurvedic medicinal plant Commiphora mukul, causes apoptosis in cancer cells but the sequence of events leading to cell death is poorly understood. We now show that guggulsterone-induced cell death in human prostate cancer cells is caused by reactive oxygen intermediate (ROI)-dependent activation of c-Jun NH(2)-terminal kinase (JNK). Exposure of PC-3 and LNCaP cells to apoptosis inducing concentrations of guggulsterone resulted in activation of JNK and p38 mitogen-activated protein kinase (p38 MAPK) in both cell lines and activation of extracellular signal-regulated kinase 1/2 (ERK1/2) in LNCaP cells. The guggulsterone-induced apoptosis in PC-3/LNCaP cells was partially but statistically significantly attenuated by pharmacologic inhibition (SP600125) as well as genetic suppression of JNK activation. On the other hand, pharmacologic inhibition of p38 MAPK activation in PC-3 or LNCaP cells (SB202190) and ERK1/2 activation in LNCaP cells (PD98059) did not protect against guggulsterone-induced cell death. The guggulsterone treatment caused generation of ROI in prostate cancer cells but not in a normal prostate epithelial cell line (PrEC), which was also resistant to guggulsterone-mediated JNK activation. The guggulsterone-induced JNK activation as well as cell death in prostate cancer cells was significantly attenuated by overexpression of catalase and superoxide dismutase. In addition, guggulsterone treatment resulted in a decrease in protein level and promoter activity of androgen receptor in LNCaP cells. In conclusion, the present study reveals that the guggulsterone-induced cell death in human prostate cancer cells is regulated by ROI-dependent activation of JNK and guggulsterone inhibits promoter activity of androgen receptor.
Singh
Shivendra V
SV
Department of Pharmacology and Urology and University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA. singhs@upmc.edu
Choi
Sunga
S
Zeng
Yan
Y
Hahm
Eun-Ryeong
ER
Xiao
Dong
D
D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D002453:Cell Cycle; D045744:Cell Line, Tumor; D029744:Commiphora / Q000737:chemistry; D004789:Enzyme Activation / Q000187:drug effects*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D008156:Luciferases / Q000378:metabolism; D048369:MAP Kinase Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D008297:Male; D011282:Pregnenediones / Q000494:pharmacology*; D011401:Promoter Regions, Genetic; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D017382:Reactive Oxygen Species / Q000378:metabolism*; D011944:Receptors, Androgen / Q000235:genetics / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
D011282:Pregnenediones; D017382:Reactive Oxygen Species; D011944:Receptors, Androgen; C023617:pregna-4,17-diene-3,16-dione; D008156:Luciferases; D013482:Superoxide Dismutase; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D048369:MAP Kinase Kinase 1; D020169:Caspases