title: Augmented pro-apoptotic effects of TRAIL and proteasome inhibitor in human promonocytic leukemic U937 cells.
abstract: TRAIL, Tumor necrosis factor-related apoptosis-inducing ligand), a member of the TNF family, is known to be cytotoxic for a high proportion of tumor cell lines. However, successful application of TRAIL in tumor therapy may depend on finding other agents that can potentiate its antitumor effects. The present study showed that the cytostatic/cytotoxic TRAIL activity against U937 cells could be significantly augmented by proteasome inhibitor PSI, as revealed by MTT assay. Increased cytostatic/cytotoxic effect on U937 cells by TRAIL/PSI combined treatment was caused by apoptosis, as shown by an increased PARP cleavage rate. TRAIL/PSI did not affect the level of mRNA expression for TRAIL receptors (DR4, DR5, DcR1) and other apoptosis signal transduction molecules (TRADD, caspase-8).
authors.affiliation: Department of Immunology, Medical University of Warsaw, 5 Chałubinskiego Str., PL 02 004 Warsaw, Poland.
authors.forename: I
authors.initials: I
authors.lastname: Młynarczuk
authors.forename: G
authors.initials: G
authors.lastname: Hoser
authors.forename: T
authors.initials: T
authors.lastname: Grzela
authors.forename: T
authors.initials: T
authors.lastname: Stokłosa
authors.forename: C
authors.initials: C
authors.lastname: Wójcik
authors.forename: J
authors.initials: J
authors.lastname: Malejczyk
authors.forename: M
authors.initials: M
authors.lastname: Jakóbisiak
mesh_terms: D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology*; D004357:Drug Synergism; D006801:Humans; D008562:Membrane Glycoproteins / Q000494:pharmacology*; D009097:Multienzyme Complexes / Q000378:metabolism*; D009842:Oligopeptides / Q000494:pharmacology*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D020298:U937 Cells
chemical_list: D051017:Apoptosis Regulatory Proteins; D015853:Cysteine Proteinase Inhibitors; D008562:Membrane Glycoproteins; D009097:Multienzyme Complexes; D009842:Oligopeptides; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; C090535:benzyloxycarbonyl-isoleucyl-glutamyl(O-tert-butyl)-alanyl-leucinal; D011065:Poly(ADP-ribose) Polymerases; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex