Abstract | PURPOSE: EXPERIMENTAL DESIGN:
HNSCC cell lines JHU-011, -012 and -019, and a leukemia control cell line HL-60 were assayed for DeltaPsim after valinomycin treatment by staining with mitochondrial-membrane-potential-specific probe JC-1 and stained with apoptosis-specific probe annexin-V to measure their rate of apoptosis by FACS. Western blotting was also applied to detect cytoplasmic cytochrome c release. RESULTS: DeltaPsim in head and neck cell lines started to show slight loss of DeltaPsim, while HL-60 showed significant loss of DeltaPsim after 30 min of treatment. All cell lines demonstrated complete mitochondrial depolarization within 24 h, however, only the control cell line HL-60 underwent apoptosis. In addition, HNSCC cell lines did not demonstrate cytoplasmic cytochrome c release despite significant mitochondrial membrane depolarization, while HL-60 cell initiated apoptosis and cytochcrome c release after 24 h of treatment. CONCLUSIONS:
Head and neck cancer cell lines exhibit defects in mitochondrial-membrane-depolarization-induced apoptosis as well as impaired release of cytochrome c despite significant mitochondrial membrane depolarization. Proximal defects in the mitochondrial apoptosis pathway are a feature of HNSCC.
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Authors | Ming Zhao, Wojciech K Mydlarz, Shaoyu Zhou, Joseph Califano |
Journal | ORL; journal for oto-rhino-laryngology and its related specialties
(ORL J Otorhinolaryngol Relat Spec)
Vol. 70
Issue 4
Pg. 257-63
( 2008)
ISSN: 1423-0275 [Electronic] Switzerland |
PMID | 18483464
(Publication Type: Comparative Study, Journal Article)
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Copyright | Copyright 2008 S. Karger AG, Basel. |
Chemical References |
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Topics |
- Apoptosis
(physiology)
- Blotting, Western
- Carcinoma, Squamous Cell
(metabolism, pathology)
- Cell Line, Tumor
- Cytochromes c
(biosynthesis)
- Flow Cytometry
- Head and Neck Neoplasms
(metabolism, pathology)
- Humans
- Membrane Potential, Mitochondrial
(physiology)
- Mitochondria
(metabolism, pathology)
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