Autor: |
Hong Zhu, Wei Yang, Ling-juan He, Wan-jing Ding, Lin Zheng, Si-da Liao, Ping Huang, Wei Lu, Qiao-jun He, Bo Yang |
Jazyk: |
angličtina |
Rok vydání: |
2012 |
Předmět: |
|
Zdroj: |
PLoS ONE, Vol 7, Iss 12, p e52333 (2012) |
Druh dokumentu: |
article |
ISSN: |
1932-6203 |
DOI: |
10.1371/journal.pone.0052333 |
Popis: |
The human hepatocellular carcinoma (HCC) represents biologically aggressive and chemo-resistant cancers. Owing to the low affinity with the apoptotic factor Mcl-1, the BH3 mimetic drug ABT-737 failed to exert potent cancer-killing activities in variety of cancer models including HCC. The current study demonstrated that combining ABT-737 and Celastrol synergistically suppressed HCC cell proliferation, and induced apoptosis which was accompanied with the activation of caspase cascade and release of cytochrome c from mitochondria. Further study revealed that the enhanced Noxa caused by Celastrol was the key factor for the synergy, since small interfering RNA-mediated knockdown of Noxa expression in HCC cells resulted in decreased apoptosis and attenuated anti-proliferative effects of the combination. In addition, our study unraveled that, upon Celastrol exposure, the activation of endoplasmic reticulum (ER) stress, specifically, the eIF2α-ATF4 pathway played indispensable roles in the activation of Noxa, which was validated by the observation that depletion of ATF4 significantly abrogated the Noxa elevation by Celastrol. Our findings highlight a novel signaling pathway through which Celastrol increase Noxa expression, and suggest the potential use of ATF4-mediated regulation of Noxa as a promising strategy to improve the anti-cancer activities of ABT-737. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
|