Abstract | PURPOSE: EXPERIMENTAL DESIGN AND RESULTS: The viability of TRAMP-C1 and TRAMP-C2 cells was reduced significantly in the presence of PEITC in a concentration-dependent manner as determined by sulforhodamine B and trypan blue dye exclusion assays. Treatment of TRAMP-derived cells with PEITC revealed features characteristic of apoptosis induction, including appearance of subdiploid cells (determined by flow cytometry), cytoplasmic histone-associated DNA fragmentation (determined by an ELISA assay), and cleavage of caspase-3 (determined by immunoblotting). The PEITC-induced apoptosis in TRAMP-derived cells was associated with a marked increase in the level of proapoptotic protein Bak and/or a decrease in the levels of antiapoptotic protein Mcl-1 or Bcl-xL and disruption of mitochondrial membrane potential. The SV40 immortalized mouse embryonic fibroblasts derived from Bak and Bax double knockout mice were significantly more resistant to PEITC-induced DNA fragmentation compared with wild-type or Bak-/- mouse embryonic fibroblasts. The PEITC-induced apoptosis in both cell lines was significantly attenuated in the presence of caspase inhibitors zVAD-fmk, zLEHD-fmk, and zIETD-fmk. Oral administration of PEITC (9 or 12 micromol PEITC/d, Monday-Friday) significantly retarded growth of TRAMP-C1 xenografts in nude mice without causing weight loss or any other side effects. CONCLUSION: The results of the present study indicate that caspase-dependent apoptosis by PEITC is mediated by Bak and Bax proteins.
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Authors | Dong Xiao, Yan Zeng, Sunga Choi, Karen L Lew, Joel B Nelson, Shivendra V Singh |
Journal | Clinical cancer research : an official journal of the American Association for Cancer Research
(Clin Cancer Res)
Vol. 11
Issue 7
Pg. 2670-9
(Apr 01 2005)
ISSN: 1078-0432 [Print] United States |
PMID | 15814648
(Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Amino Acid Chloromethyl Ketones
- Bak1 protein, mouse
- Bax protein, mouse
- Caspase Inhibitors
- Cysteine Proteinase Inhibitors
- Isothiocyanates
- Membrane Proteins
- Plant Preparations
- Proto-Oncogene Proteins c-bcl-2
- bcl-2 Homologous Antagonist-Killer Protein
- bcl-2-Associated X Protein
- benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone
- phenethyl isothiocyanate
- Caspases
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Topics |
- Adenocarcinoma
(metabolism, pathology, prevention & control)
- Amino Acid Chloromethyl Ketones
(pharmacology)
- Animals
- Apoptosis
(drug effects)
- Caspase Inhibitors
- Caspases
(metabolism)
- Cell Line, Tumor
- Cell Survival
(drug effects)
- Cysteine Proteinase Inhibitors
(pharmacology)
- Dose-Response Relationship, Drug
- Immunoblotting
- Intracellular Membranes
(drug effects, physiology)
- Isothiocyanates
(pharmacology)
- Male
- Membrane Potentials
(drug effects)
- Membrane Proteins
(genetics, metabolism)
- Mice
- Mice, Knockout
- Mice, Transgenic
- Mitochondria
(drug effects, physiology)
- Neoplasms
(metabolism, pathology, prevention & control)
- Plant Preparations
(chemistry, pharmacology)
- Prostatic Neoplasms
(metabolism, pathology, prevention & control)
- Proto-Oncogene Proteins c-bcl-2
(genetics, metabolism)
- Vegetables
(chemistry)
- bcl-2 Homologous Antagonist-Killer Protein
- bcl-2-Associated X Protein
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