Abstract | PURPOSE: METHODS: RESULTS: Of the three glioblastoma cell lines, the U87 cells were least sensitive to adaphostin. These cells were also least sensitive to tert-butyl hydroperoxide, indicating that sensitivity to a direct oxidant stress mirrors the cells' adaphostin sensitivities. In addition, the antioxidant N-acetylcysteine, (NAC) was protective against adaphostin-induced apoptosis. Direct measurement of intracellular peroxides showed a transient increase in the two less sensitive cell lines (U87 and LN18) which diminishes by 24 h. In contrast, U251 cells, which are most sensitive to adaphostin, display a sustained increase in the ROS levels. After the initial increase in intracellular peroxides, the heat shock protein and antioxidant heme oxygenase-1 (HO-1) was upregulated. Levels of other antioxidant proteins, such as catalase and thioredoxin, however, were not altered by adaphostin in glioblastoma cell lines. NAC attenuated HO-1 upregulation, confirming the time course analysis. CONCLUSIONS: These results suggest a primary role for ROS in adaphostin-induced apoptosis in glioblastoma. Our data indicate that the duration of intracellular ROS levels is a key factor in mediating sensitivity to adaphostin. Furthermore, upregulation of HO-1 is a novel molecular marker of adaphostin's action. The kinetics with which adaphostin upregulates HO-1 correlates with sensitivity to the drug. Taken together, our data indicate that a cell's ability to cope with ROS dictates sensitivity to adaphostin and conceivably other chemotherapies that cause redox perturbations.
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Authors | Jason Long, Tejas Manchandia, Kechen Ban, Shan Gao, Claudia Miller, Joya Chandra |
Journal | Cancer chemotherapy and pharmacology
(Cancer Chemother Pharmacol)
Vol. 59
Issue 4
Pg. 527-35
(Mar 2007)
ISSN: 0344-5704 [Print] Germany |
PMID | 16924499
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Antineoplastic Agents
- Hydroquinones
- NSC 680410
- RNA, Messenger
- Reactive Oxygen Species
- Heme Oxygenase-1
- Fusion Proteins, bcr-abl
- Glutathione
- Adamantane
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Topics |
- Adamantane
(analogs & derivatives, pharmacology)
- Antineoplastic Agents
(pharmacology)
- Apoptosis
(drug effects)
- Cell Line, Tumor
- DNA Fragmentation
(drug effects)
- Fusion Proteins, bcr-abl
(antagonists & inhibitors)
- Glioblastoma
(drug therapy, metabolism)
- Glutathione
(analysis)
- Heme Oxygenase-1
(genetics)
- Humans
- Hydroquinones
(pharmacology)
- RNA, Messenger
(analysis)
- Reactive Oxygen Species
(metabolism)
- Up-Regulation
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