title: CD27-triggering on primary plasma cell leukaemia cells has anti-apoptotic effects involving mitogen activated protein kinases.
abstract: Primary plasma cell leukaemia (PCL) is a rare plasma cell malignancy, which is related to multiple myeloma (MM) and is characterized by a poor prognosis. In a previous study we demonstrated that PCL plasma cells display a high expression of CD27, in contrast to MM plasma cells. The present study was set out to assess the functional properties of CD27 expressed on PCL plasma cells by triggering with its ligand CD70. Using CD27-expressing purified plasma cells from a PCL patient we demonstrated that CD27-triggering modestly inhibited spontaneous and dexamethasone-induced apoptosis. In vitro stimulation and Western blotting showed that activation of p38 and extracellular-regulated kinase 1/2 (ERK1/2) mitogen-activated protein kinases (MAPK) was associated with CD27-mediated signal transduction. Specific inhibition of p38 and ERK1/2 MAPK abolished the anti-apoptotic effects of CD27-triggering. Interestingly, simultaneous inhibition of p38 and ERK1/2 strongly sensitized PCL cells for dexamethasone-induced apoptosis. Finally, in dexamethasone-treated PCL cells, CD27-triggering was associated with persistent DNA-binding activity of activator protein 1 (AP-1) but not of nuclear factor-kappaB. These findings suggest that, in primary PCL, specific anti-apoptotic pathways exist that might provide novel therapeutic targets.
authors.affiliation: Department of Cell Biology, Section Histology and Immunology, Faculty of Medical Sciences, University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
authors.forename: Jeroen E J
authors.initials: JE
authors.lastname: Guikema
authors.forename: Edo
authors.initials: E
authors.lastname: Vellenga
authors.forename: Wayel H
authors.initials: WH
authors.lastname: Abdulahad
authors.forename: Sjoerd
authors.initials: S
authors.lastname: Hovenga
authors.forename: Nicolaas A
authors.initials: NA
authors.lastname: Bos
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western / Q000379:methods; D002070:Butadienes / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D024202:Electrophoretic Mobility Shift Assay; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005938:Glucocorticoids / Q000494:pharmacology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D007952:Leukemia, Plasma Cell / Q000276:immunology*; D020935:MAP Kinase Signaling System; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D009570:Nitriles / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018709:Statistics, Nonparametric; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014407:Tumor Cells, Cultured; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000276:immunology*; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D002070:Butadienes; D004791:Enzyme Inhibitors; D005938:Glucocorticoids; D007093:Imidazoles; D009570:Nitriles; D011725:Pyridines; D018808:Transcription Factor AP-1; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7; C113580:U 0126; D003907:Dexamethasone; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C093642:SB 203580