Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
2009-10-2
pubmed:abstractText
Smac mimetic compounds (SMC) are novel small molecules being developed for cancer therapy. The mechanism of SMC-induced sensitivity in cancer cells depends on autocrine release of tumor necrosis factor alpha (TNFalpha); however, potential mechanisms of resistance remain unknown. Here, we investigated the molecular profile and cytotoxic responsiveness of a diverse panel of 51 cancer cell lines to combinations of a dimeric SMC (AEG40730), death ligand TNFalpha, and tumor necrosis factor-related apoptosis-inducing ligand. Synergy was seen in combination with death receptor agonists in some cells, although single-agent activity was limited to a fewsensitive lines. Unexpectedly, the majority of cell lines resistant to combinations of SMC-AEG40730 and death ligands expressed caspase-8, FADD, RIP1, and ligand receptors necessary for apoptosis execution. Furthermore, TNFalpha-mediated ubiquitination of RIP1 was repressed by SMC-AEG40730 treatment, leading to the formation of the proapoptosis complex II. However, in resistant cancer cells, SMC-AEG40730 repressed TNFalpha-mediated c-jun-NH(2)-kinase activation and the levels of caspase-8 inhibitor c-FLIP were persistently elevated, in contrast to SMC-responsive cancer cells. Importantly, the silencing of c-FLIP restored SMC sensitivity in previously resistant cancer cells by allowing ligand-mediated activation of caspase-8 and caspase-3 to proceed. Together, these results provide mechanistic insight into the action of SMCs, demonstrating that the deciphering of the relevant molecular signature in cancer cells leads to the prediction of cancer cell responsiveness to SMC treatment. Furthermore, a majority of resistant cancer cells were sensitized to SMC-AEG40730 and TNFalpha by down-regulating c-FLIP, suggesting novel approaches in the use of SMCs and c-FLIP antagonists in treating cancer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/AEG 40730, http://linkedlifedata.com/resource/pubmed/chemical/AGFG1 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Alkynes, http://linkedlifedata.com/resource/pubmed/chemical/CASP8 and FADD-Like Apoptosis..., http://linkedlifedata.com/resource/pubmed/chemical/Dipeptides, http://linkedlifedata.com/resource/pubmed/chemical/NF-kappa B, http://linkedlifedata.com/resource/pubmed/chemical/Nuclear Pore Complex Proteins, http://linkedlifedata.com/resource/pubmed/chemical/RNA-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/TNF-Related Apoptosis-Inducing..., http://linkedlifedata.com/resource/pubmed/chemical/TNFSF10 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Tumor Necrosis Factor-alpha
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1538-7445
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
69
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7729-38
pubmed:dateRevised
2010-9-20
pubmed:meshHeading
pubmed-meshheading:19773432-Alkynes, pubmed-meshheading:19773432-Apoptosis, pubmed-meshheading:19773432-Breast Neoplasms, pubmed-meshheading:19773432-CASP8 and FADD-Like Apoptosis Regulating Protein, pubmed-meshheading:19773432-Cell Line, Tumor, pubmed-meshheading:19773432-Dipeptides, pubmed-meshheading:19773432-Down-Regulation, pubmed-meshheading:19773432-Drug Resistance, Neoplasm, pubmed-meshheading:19773432-Drug Screening Assays, Antitumor, pubmed-meshheading:19773432-Drug Synergism, pubmed-meshheading:19773432-Humans, pubmed-meshheading:19773432-NF-kappa B, pubmed-meshheading:19773432-Neoplasms, pubmed-meshheading:19773432-Neuroblastoma, pubmed-meshheading:19773432-Nuclear Pore Complex Proteins, pubmed-meshheading:19773432-RNA-Binding Proteins, pubmed-meshheading:19773432-Signal Transduction, pubmed-meshheading:19773432-TNF-Related Apoptosis-Inducing Ligand, pubmed-meshheading:19773432-Tumor Necrosis Factor-alpha, pubmed-meshheading:19773432-Ubiquitination
pubmed:year
2009
pubmed:articleTitle
Down-regulation of c-FLIP Enhances death of cancer cells by smac mimetic compound.
pubmed:affiliation
Apoptosis Research Centre, Children's Hospital of Eastern Ontario Research Institute and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't