title: Targeting the tumor necrosis factor-related apoptosis-inducing ligand path in neuroblastoma.
abstract: The identification of the tumor necrosis factor (TNF) superfamily member TNF-related apoptosis-inducing ligand (TRAIL) a few years ago generated considerable enthusiasm for it as a potential cancer therapeutic agent. This is because TRAIL shows potent apoptosis inducing activity in a wide spectrum of transformed cell lines but not in cell lines derived from normal tissue origin. As the details in the signal transduction pathway of TRAIL-induced apoptosis are clarified, various defects of TRAIL pathway have been identified in TRAIL resistant cancer cells. Neuroblastoma is the most common extracranial solid tumor in children and those with a poor prognosis require more sensitive therapies. Unlike other cancer cells, most neuroblastoma cell lines are resistant to TRAIL induced apoptosis and the resistance correlates with caspase 8 deficiency, which is attributed to the methylation of the gene. Interferon (IFN)-gamma induces caspase 8 expression in most neuroblastoma cell lines regardless of the methylation status but fails to sensitize most NB to TRAIL. Further analysis indicates a TRAIL receptor deficiency contributes to TRAIL resistance in NB. Multiple lesions suggest that this path may play an important role in tumorigenesis and/ or evasion from therapies. Furthermore it indicates that the clinical application of TRAIL in NB will require a multi-modality approach. Important questions remain unanswered: How does IFN-gamma induce caspase 8 and why is the induction heterogeneous? How to stimulate the caspase 8 induction in cells that fail to respond to IFN-gamma? How to target other TRAIL pathway lesions with the clinically feasible approaches?
authors.affiliation: Cell and Molecular Biology Section, Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, NIH, 10 Center Dr., Bethesda, MD 20892, USA.
authors.forename: Xuezhong
authors.initials: X
authors.lastname: Yang
authors.forename: Carol J
authors.initials: CJ
authors.lastname: Thiele
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases / Q000096:biosynthesis; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D008024:Ligands; D008562:Membrane Glycoproteins / Q000494:pharmacology*; D009447:Neuroblastoma / Q000201:enzymology / Q000473:pathology*; D018124:Receptors, Tumor Necrosis Factor / Q000378:metabolism; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D051017:Apoptosis Regulatory Proteins; D008024:Ligands; D008562:Membrane Glycoproteins; D018124:Receptors, Tumor Necrosis Factor; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; C505530:CASP8 protein, human; C506433:CASP9 protein, human; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases