ABSTRACT
Hsp90 inhibitor geldanamycin and parthenolide have been shown to induce apoptosis in cancer cells. However, the combined effect of geldanamycin and parthenolide on epithelial ovarian cancer cells has not been studied. In respect of cell death process, we investigated the promoting effect of parthenolide on geldanamycin-induced apoptosis in the human epithelial ovarian carcinoma cell lines OVCAR-3 and SK-OV-3. Geldanamycin induced a decrease in Bid, Bcl-2, Bcl-xL and survivin protein levels; an increase in Bax and tumour suppressor p53 levels; loss of the mitochondrial transmembrane potential; cytochrome c release; activation of caspases (-8, -9 and -3); cleavage of PARP-1; and increase in the reactive oxygen species formation. Parthenolide enhanced geldanamycin-induced changes in the apoptosis-related protein levels, reactive oxygen species formation, nuclear damage and cell death. The combined effect was inhibited by the addition of oxidant scavengers. The results suggest that parthenolide may potentiate the apoptotic effect of geldanamycin on ovarian carcinoma cell lines by the activation of the caspase-8- and Bid-dependent pathway and the mitochondria-mediated apoptotic pathway. The apoptosis-promoting effect seems to be mediated by the stimulatory effect on the formation of reactive oxygen species.
Subject(s)
Apoptosis/drug effects , Benzoquinones/pharmacology , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Lactams, Macrocyclic/pharmacology , Reactive Oxygen Species/metabolism , Sesquiterpenes/pharmacology , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Blotting, Western , Carcinoma, Ovarian Epithelial , Caspase 3/genetics , Caspase 3/metabolism , Caspase 8/genetics , Caspase 8/metabolism , Caspase 9/genetics , Caspase 9/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Cytochromes c/genetics , Cytochromes c/metabolism , Female , HSP90 Heat-Shock Proteins/metabolism , Humans , Mitochondria/drug effects , Mitochondria/metabolism , Neoplasms, Glandular and Epithelial/pathology , Ovarian Neoplasms/pathology , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , bcl-2-Associated X Protein/genetics , bcl-2-Associated X Protein/metabolismABSTRACT
To assess the ability of 3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole (YC-1) to promote apoptosis, we investigated the effect of YC-1 on tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-induced apoptosis in the human epithelial ovarian carcinoma cell lines. In OVCAR-3 and SK-OV-3 cell lines, we examined the stimulatory effect of YC-1 on TRAIL-induced apoptosis by monitoring cell death, nuclear damage, changes in apoptosis-related protein levels, activation of caspases and changes in the mitochondrial transmembrane potential. TRAIL induced a decrease in Bid, Bcl-2 and Bcl-xL protein levels, increase in cleaved Bid and Bax levels, loss of the mitochondrial transmembrane potential, cytochrome c release, activation of caspases (-8, -9 and -3) and an increase in the tumour suppressor p53 levels. YC-1 enhanced TRAIL-induced apoptosis-related protein activation, nuclear damage and cell death. Results from this study suggest that YC-1 may enhance the apoptotic effect of TRAIL on ovarian carcinoma cell lines by increasing the activation of the caspase-8- and Bid-dependent pathways and the mitochondria-mediated apoptotic pathway, leading to caspase activation. YC-1 may confer a benefit in TRAIL treatment of epithelial ovarian adenocarcinoma.
