title: Depsipeptide (FR901228) enhances the cytotoxic activity of TRAIL by redistributing TRAIL receptor to membrane lipid rafts.
abstract: TRAIL (TNF-related apoptosis-inducing ligand) induces apoptosis in various tumor cell types and is under investigation as a cancer therapeutic. The development of a recombinant adenovirus encoding the full-length human TRAIL gene (Ad5-TRAIL) replaces the need for large quantities of soluble TRAIL protein in tumor suppressive therapies. However, the full potential of Ad5-TRAIL has not yet been maximized. Recent investigation of a histone deacetylase inhibitor, depsipeptide (FR901228), has demonstrated that it increases cellular susceptibility to adenovirus infection and augments adenoviral transgene expression. Thus, studies were initiated to evaluate the ability of depsipeptide to enhance the cytotoxic activity of Ad5-TRAIL against human prostate tumor cells. In vitro, depsipeptide increased expression of coxsackie-adenovirus receptor, leading to increased adenoviral infection and transgene expression. Additionally, tumor cell killing by Ad5-TRAIL was higher following depsipeptide pretreatment. More surprisingly, depsipeptide also increased prostate tumor cell sensitivity to TRAIL-induced apoptosis. Investigation into the mechanism responsible for increased TRAIL responsiveness revealed increased levels of TRAIL-R1 and -R2 in membrane lipid rafts following depsipeptide treatment. These results indicate that depsipeptide is a potent agent for enhancing the activity of Ad5-TRAIL by multiple mechanisms, allowing for a more efficient use of Ad5-TRAIL as an antitumor therapy.
authors.affiliation: Department of Urology, University of Iowa, 200 Hawkins Drive, Iowa City, IA 52242-1089, USA.
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Vanoosten
authors.forename: Jill M
authors.initials: JM
authors.lastname: Moore
authors.forename: Aaron T
authors.initials: AT
authors.lastname: Ludwig
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Griffith
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000903:Antibiotics, Antineoplastic / Q000627:therapeutic use*; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D003131:Combined Modality Therapy; D047630:Depsipeptides / Q000627:therapeutic use*; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D015870:Gene Expression / Q000187:drug effects; D015316:Genetic Therapy; D005822:Genetic Vectors; D056572:Histone Deacetylase Inhibitors; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D021962:Membrane Microdomains / Q000737:chemistry / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000628:therapy*; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor / Q000032:analysis / Q000378:metabolism*; D053221:TNF-Related Apoptosis-Inducing Ligand; D019076:Transgenes; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics* / Q000378:metabolism
chemical_list: D000903:Antibiotics, Antineoplastic; D051017:Apoptosis Regulatory Proteins; D047630:Depsipeptides; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D008562:Membrane Glycoproteins; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D053221:TNF-Related Apoptosis-Inducing Ligand; C105190:TNFRSF10A protein, human; C505639:TNFRSF10B protein, human; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; C087123:romidepsin