Abstract |
The AKT2 kinase (protein kinas Bβ) is frequently overexpressed in malignant gliomas. In this study, the human glioblastoma cell line U87 was stably transfected with a lentivirus vector expressing a short hairpin RNA ( shRNA) targeting AKT2. Knockdown of AKT2 by the shRNA inhibited U87 cell proliferation and increased the rate of apoptosis. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and Western blot analysis revealed that cells stably underexpressing AKT2 showed lower expression of the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2) and enhanced expression of the apoptosis effector caspase-3 compared to U87 cells stably transfected with a control vector. Furthermore, expression levels of AKT2 were correlated with the IC50 of the antitumor drug VM-26 ( teniposide); the VM-26 IC50 was reduced from 6.46±0.42μg/ml in control glioma cells to 1.15±0.22μg/ml in U87 cells underexpressing AKT2. Combined AKT2 knockdown and VM-26 treatment inhibited cell proliferation in vitro more effectively than either treatment alone. Knockdown of AKT2 expression was associated with decreased expression of the multidrug resistance-associated protein 1 ( MRP1) without affecting MRP1 mRNA expression. However, the mRNA and protein levels of MDR1 ( p-glycoprotein) were unaffected by AKT2 knockdown. These results indicate that inhibition of AKT2 expression may be an effective means for overcoming AKT2-associated chemoresistance in human malignant glioma cells and may represent a potential gene-targeting approach to treat glioma.
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Authors | Yong Cui, Qi Wang, Junyu Wang, Yan Dong, Chun Luo, Guohan Hu, Yicheng Lu |
Journal | Brain research
(Brain Res)
Vol. 1469
Pg. 1-9
(Aug 21 2012)
ISSN: 1872-6240 [Electronic] Netherlands |
PMID | 22771706
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Copyright | Copyright © 2012 Elsevier B.V. All rights reserved. |
Chemical References |
- Antineoplastic Agents
- Teniposide
- Proto-Oncogene Proteins c-akt
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Topics |
- Antineoplastic Agents
(pharmacology)
- Apoptosis
(drug effects, genetics)
- Cell Line, Tumor
- Cell Proliferation
(drug effects)
- Glioma
(genetics, metabolism)
- HEK293 Cells
- Humans
- Proto-Oncogene Proteins c-akt
(genetics, metabolism)
- RNA Interference
- Teniposide
(pharmacology)
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