title: Ectopic microRNA-150-5p transcription sensitizes glucocorticoid therapy response in MM1S multiple myeloma cells but fails to overcome hormone therapy resistance in MM1R cells.
abstract: Glucocorticoids (GCs) selectively trigger cell death in the multiple myeloma cell line MM1S which express NR3C1/Glucocorticoid Receptor (GR) protein, but fail to kill MM1R cells which lack GR protein. Given recent demonstrations of altered microRNA profiles in a diverse range of haematological malignancies and drug resistance, we characterized GC inducible mRNA and microRNA transcription profiles in GC sensitive MM1S as compared to GC resistant MM1R cells. Transcriptome analysis revealed that GCs regulate expression of multiple genes involved in cell cycle control, cell organization, cell death and immunological disease in MM1S cells, which remain unaffected in MM1R cells. With respect to microRNAs, mir-150-5p was identified as the most time persistent GC regulated microRNA, out of 5 QPCR validated microRNAs (mir-26b, mir-125a-5p, mir-146-5p, mir-150-5p, and mir-184), which are GC inducible in MM1S but not in MM1R cells. Functional studies further revealed that ectopic transfection of a synthetic mir-150-5p mimics GR dependent gene expression changes involved in cell death and cell proliferation pathways. Remarkably, despite the gene expression changes observed, overexpression of mir-150-5p in absence of GCs did not trigger significant cytotoxicity in MM1S or MM1R cells. This suggests the requirement of additional steps in GC induced cell death, which can not be mimicked by mir-150-5p overexpression alone. Interestingly, a combination of mir-150-5p transfection with low doses GC in MM1S cells was found to sensitize therapy response, whereas opposite effects could be observed with a mir-150-5p specific antagomir. Although mir-150-5p overexpression did not substantially change GR expression levels, it was found that mir-150-5p evokes GR specific effects through indirect mRNA regulation of GR interacting transcription factors and hormone receptors, GR chaperones, as well as various effectors of unfolded protein stress and chemokine signalling. Altogether GC-inducible mir-150-5p adds another level of regulation to GC specific therapeutic responses in multiple myeloma.
authors.affiliation: Laboratory of Protein Chemistry, Proteomics and Epigenetic Signalling (PPES), Department of Biomedical Sciences, University of Antwerp (UA), Antwerp, Belgium; Laboratory of Eukaryotic Gene Expression and Signal Transduction (LEGEST), Department of Physiology, Ghent University, Ghent, Belgium.
authors.forename: Ajay
authors.initials: A
authors.lastname: Palagani
authors.affiliation: Center of Medical Genetics, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Laboratory of Cancer Research and Clinical Oncology, Department of Medical Oncology, University of Antwerp/Antwerp University Hospital, Antwerp, Belgium.
authors.forename: Ken
authors.initials: K
authors.lastname: Op de Beeck
authors.affiliation: Biomedical Informatics Research Center Antwerp (Biomina), University of Antwerp & University Hospital Antwerp, Antwerp, Belgium; Advanced Database Research and Modelling (ADReM), Department of Mathematics & Computer sciences, University of Antwerp (UA), Antwerp, Belgium.
authors.forename: Stefan
authors.initials: S
authors.lastname: Naulaerts
authors.affiliation: Laboratory of Protein Chemistry, Proteomics and Epigenetic Signalling (PPES), Department of Biomedical Sciences, University of Antwerp (UA), Antwerp, Belgium.
authors.forename: Jolien
authors.initials: J
authors.lastname: Diddens
authors.affiliation: Laboratory of Protein Chemistry, Proteomics and Epigenetic Signalling (PPES), Department of Biomedical Sciences, University of Antwerp (UA), Antwerp, Belgium.
authors.forename: Chandra
authors.initials: C
authors.lastname: Sekhar Chirumamilla
authors.affiliation: Center of Medical Genetics, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium.
authors.forename: Guy
authors.initials: G
authors.lastname: Van Camp
authors.affiliation: Biomedical Informatics Research Center Antwerp (Biomina), University of Antwerp & University Hospital Antwerp, Antwerp, Belgium; Advanced Database Research and Modelling (ADReM), Department of Mathematics & Computer sciences, University of Antwerp (UA), Antwerp, Belgium.
authors.forename: Kris
authors.initials: K
authors.lastname: Laukens
authors.affiliation: Laboratory of Eukaryotic Gene Expression and Signal Transduction (LEGEST), Department of Physiology, Ghent University, Ghent, Belgium.
authors.forename: Karen
authors.initials: K
authors.lastname: Heyninck
authors.affiliation: VIB-UGent Department of Medical Protein Research, Ghent, Belgium.
authors.forename: Sarah
authors.initials: S
authors.lastname: Gerlo
authors.affiliation: Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium.
authors.forename: Pieter
authors.initials: P
authors.lastname: Mestdagh
authors.affiliation: Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium.
authors.forename: Joke
authors.initials: J
authors.lastname: Vandesompele
authors.affiliation: Laboratory of Protein Chemistry, Proteomics and Epigenetic Signalling (PPES), Department of Biomedical Sciences, University of Antwerp (UA), Antwerp, Belgium; Laboratory of Eukaryotic Gene Expression and Signal Transduction (LEGEST), Department of Physiology, Ghent University, Ghent, Belgium.
authors.forename: Wim Vanden
authors.initials: WV
authors.lastname: Berghe
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000187:drug effects*; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D018925:Chemokines / Q000378:metabolism; D004249:DNA Damage / Q000187:drug effects; D003907:Dexamethasone / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects; D005260:Female; D006801:Humans; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D009101:Multiple Myeloma / Q000378:metabolism / Q000473:pathology; D016376:Oligonucleotides, Antisense / Q000378:metabolism; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism; D014162:Transfection; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D018925:Chemokines; D003907:Dexamethasone; D035683:MicroRNAs; D016376:Oligonucleotides, Antisense; D058570:TOR Serine-Threonine Kinases; C533097:MIR150, human