title: YB-1 dependent oncolytic adenovirus efficiently inhibits tumor growth of glioma cancer stem like cells.
abstract: BACKGROUND
  The brain cancer stem cell (CSC) model describes a small subset of glioma cells as being responsible for tumor initiation, conferring therapy resistance and tumor recurrence. In brain CSC, the PI3-K/AKT and the RAS/mitogen activated protein kinase (MAPK) pathways are found to be activated. In consequence, the human transcription factor YB-1, knowing to be responsible for the emergence of drug resistance and driving adenoviral replication, is phosphorylated and activated. With this knowledge, YB-1 was established in the past as a biomarker for disease progression and prognosis. This study determines the expression of YB-1 in glioblastoma (GBM) specimen in vivo and in brain CSC lines. In addition, the capacity of Ad-Delo3-RGD, an YB-1 dependent oncolytic adenovirus, to eradicate CSC was evaluated both in vitro and in vivo.
  
  
  METHODS
  YB-1 expression was investigated by immunoblot and immuno-histochemistry. In vitro, viral replication as well as the capacity of Ad-Delo3-RGD to replicate in and, in consequence, to kill CSC was determined by real-time PCR and clonogenic dilution assays. In vivo, Ad-Delo3-RGD-mediated tumor growth inhibition was evaluated in an orthotopic mouse GBM model. Safety and specificity of Ad-Delo3-RGD were investigated in immortalized human astrocytes and by siRNA-mediated downregulation of YB-1.
  
  
  RESULTS
  YB-1 is highly expressed in brain CSC lines and in GBM specimen. Efficient viral replication in and virus-mediated lysis of CSC was observed in vitro. Experiments addressing safety aspects of Ad-Delo3-RGD showed that (i) virus production in human astrocytes was significantly reduced compared to wild type adenovirus (Ad-WT) and (ii) knockdown of YB-1 significantly reduced virus replication. Mice harboring othotopic GBM developed from a temozolomide (TMZ)-resistant GBM derived CSC line which was intratumorally injected with Ad-Delo3-RGD survived significantly longer than mice receiving PBS-injections or TMZ treatment.
  
  
  CONCLUSIONS
  The results of this study supported YB-1 based virotherapy as an attractive therapeutic strategy for GBM treatment which will be exploited further in multimodal treatment concepts.
authors.affiliation: Institut für Experimentelle Onkologie & Therapieforschung, Klinikum rechts der Isar, Technische Universität München, Ismaninger Str, 22, 81675 München, Germany. per.s.holm@lrz.tum.de.
authors.forename: Klaus
authors.initials: K
authors.lastname: Mantwill
authors.forename: Ulrike
authors.initials: U
authors.lastname: Naumann
authors.forename: Janina
authors.initials: J
authors.lastname: Seznec
authors.forename: Vroni
authors.initials: V
authors.lastname: Girbinger
authors.forename: Hermann
authors.initials: H
authors.lastname: Lage
authors.forename: Pawel
authors.initials: P
authors.lastname: Surowiak
authors.forename: Dagmar
authors.initials: D
authors.lastname: Beier
authors.forename: Michel
authors.initials: M
authors.lastname: Mittelbronn
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schlegel
authors.forename: Per Sonne
authors.initials: PS
authors.lastname: Holm
mesh_terms: D000256:Adenoviridae / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D001932:Brain Neoplasms / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D015687:Cell Hypoxia / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D015254:DNA Modification Methylases / Q000378:metabolism; D045643:DNA Repair Enzymes / Q000378:metabolism; D003606:Dacarbazine / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000187:drug effects; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D004789:Enzyme Activation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005910:Glioma / Q000201:enzymology / Q000473:pathology*; D006801:Humans; D051379:Mice; D014411:Neoplastic Stem Cells / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D050504:Oncolytic Viruses / Q000187:drug effects / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D000077204:Temozolomide; D025521:Tumor Suppressor Proteins / Q000378:metabolism; D014779:Virus Replication / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays; D051840:Y-Box-Binding Protein 1 / Q000378:metabolism*
chemical_list: D034741:RNA, Small Interfering; D025521:Tumor Suppressor Proteins; D051840:Y-Box-Binding Protein 1; D003606:Dacarbazine; D015254:DNA Modification Methylases; C515491:MGMT protein, human; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases; D045643:DNA Repair Enzymes; D000077204:Temozolomide
references.citation: Cell. 2008 May 16;133(4):704-15
references.pmid: 18485877
references.citation: J Virol. 2006 Apr;80(8):3904-11
references.pmid: 16571807
references.citation: J Natl Cancer Inst. 2007 Sep 19;99(18):1410-4
references.pmid: 17848677
references.citation: Cancer Gene Ther. 2009 Oct;16(10):753-63
references.pmid: 19363467
references.citation: Proc Natl Acad Sci U S A. 1985 Feb;82(4):1257-61
references.pmid: 2983332
references.citation: Expert Opin Biol Ther. 2001 May;1(3):525-38
references.pmid: 11727523
references.citation: Oncotarget. 2011 May;2(5):401-6
references.pmid: 21576761
references.citation: Int J Cancer. 2007 May 15;120(10):2110-8
references.pmid: 17266041
references.citation: Nat Med. 1997 Apr;3(4):447-50
references.pmid: 9095180
references.citation: Nature. 2006 Dec 7;444(7120):756-60
references.pmid: 17051156
references.citation: Cell. 1981 Oct;26(2 Pt 2):213-20
references.pmid: 7332929
references.citation: Clin Cancer Res. 2004 Aug 15;10(16):5299-312
references.pmid: 15328165
references.citation: Cancer Res. 2008 Jan 1;68(1):98-105
references.pmid: 18172301
references.citation: J Biol Chem. 2002 Mar 22;277(12):10427-34
references.pmid: 11788582
references.citation: Exp Hematol. 2011 May;39(5):558-69
references.pmid: 21300134
references.citation: Mol Cell Biol. 2005 Jun;25(11):4625-37
references.pmid: 15899865
references.citation: N Engl J Med. 2000 Nov 9;343(19):1350-4
references.pmid: 11070098
references.citation: Neoplasia. 2010 Jun;12(6):453-63
references.pmid: 20563248
references.citation: Clin Cancer Res. 2008 Dec 15;14(24):8205-12
references.pmid: 19088037
references.citation: Int J Cancer. 2011 Sep 1;129(5):1265-76
references.pmid: 21710499
references.citation: Neuro Oncol. 2010 Jul;12(7):756-60
references.pmid: 20388697
references.citation: Cancer Res. 2009 Apr 1;69(7):3148-56
references.pmid: 19318582
references.citation: Cancer Res. 2008 Jul 15;68(14):5706-15
references.pmid: 18632623
references.citation: Stem Cells. 2009 Oct;27(10):2383-92
references.pmid: 19658181
references.citation: Cancer Res. 2006 Jul 15;66(14):7195-202
references.pmid: 16849566
references.citation: Int J Cancer. 2002 Jan 20;97(3):278-82
references.pmid: 11774277
references.citation: PLoS Genet. 2010 Dec 02;6(12):e1001231
references.pmid: 21170361
references.citation: Cancer Res. 2003 Sep 15;63(18):5821-8
references.pmid: 14522905
references.citation: N Engl J Med. 2005 Mar 10;352(10):997-1003
references.pmid: 15758010
references.citation: J Clin Oncol. 2008 Jun 20;26(18):3015-24
references.pmid: 18565887
references.citation: FEBS Lett. 2005 Oct 10;579(24):5372-8
references.pmid: 16198352
references.citation: Mol Ther. 2007 Dec;15(12):2088-93
references.pmid: 17848962
references.citation: Lancet Oncol. 2009 May;10(5):459-66
references.pmid: 19269895
references.citation: J Neurosurg. 2001 Aug;95(2):190-8
references.pmid: 11780887
references.citation: J Clin Oncol. 2007 Apr 1;25(10):1196-208
references.pmid: 17401009
references.citation: Mod Pathol. 2009 Feb;22(2):282-90
references.pmid: 18978732
references.citation: Adv Enzyme Regul. 2006;46:249-79
references.pmid: 16854453
references.citation: Transl Oncogenomics. 2007 May 11;2:49-65
references.pmid: 23641145
references.citation: Cancer Res. 2007 May 1;67(9):4010-5
references.pmid: 17483311
references.citation: Curr Opin Biotechnol. 2007 Oct;18(5):460-6
references.pmid: 18023337
references.citation: Neuro Oncol. 2012 Dec;14(12):1452-64
references.pmid: 23132408
references.citation: Cancer Cell. 2009 May 5;15(5):402-15
references.pmid: 19411069
references.citation: Nat Clin Pract Neurol. 2008 Aug;4(8):427-35
references.pmid: 18628751
references.citation: FASEB J. 2009 Aug;23(8):2467-77
references.pmid: 19289606
references.citation: Int J Cancer. 2007 Dec 15;121(12):2801-7
references.pmid: 17724714
references.citation: Cancer Res. 2011 Aug 15;71(16):5569-78
references.pmid: 21730024
references.citation: J Thorac Oncol. 2009 Sep;4(9):1066-74
references.pmid: 19648825
references.citation: Cancer Sci. 2007 Jul;98(7):1020-6
references.pmid: 17459055
references.citation: Stem Cells. 2010 Nov;28(11):1930-9
references.pmid: 20857497
references.citation: Cancer Res. 2010 Apr 1;70(7):2840-51
references.pmid: 20332234
references.citation: Breast Cancer Res. 2008;10(6):R99
references.pmid: 19036157
references.citation: Int J Cancer. 2011 Feb 15;128(4):826-38
references.pmid: 20473906
references.citation: Nature. 2001 Nov 1;414(6859):105-11
references.pmid: 11689955
references.citation: Cell. 1987 May 22;49(4):507-13
references.pmid: 2952280
references.citation: Oncogene. 2005 Jun 16;24(26):4281-92
references.pmid: 15806160
references.citation: Breast Cancer Res. 2011 Mar 10;13(2):R28
references.pmid: 21392397
references.citation: Eur Respir J. 2004 Jan;23(1):14-9
references.pmid: 14738225
references.citation: J Neurochem. 2006 Feb;96(3):766-76
references.pmid: 16405512
references.citation: Proc Natl Acad Sci U S A. 1994 Sep 13;91(19):8802-6
references.pmid: 8090727
references.citation: Neoplasia. 2005 Sep;7(9):824-37
references.pmid: 16229805
references.citation: Cell Cycle. 2010 May;9(9):1781-91
references.pmid: 20436278
references.citation: Cell Stem Cell. 2009 Mar 6;4(3):226-35
references.pmid: 19265662
references.citation: N Engl J Med. 2005 Mar 10;352(10):987-96
references.pmid: 15758009