title: Preclinical evaluation of cyclin dependent kinase 11 and casein kinase 2 survival kinases as RNA interference targets for triple negative breast cancer therapy.
abstract: BACKGROUND
  Targeted therapies for aggressive breast cancers like triple negative breast cancer (TNBC) are needed. The use of small interfering RNAs (siRNAs) to disable expression of survival genes provides a tool for killing these cancer cells. Cyclin dependent kinase 11 (CDK11) is a survival protein kinase that regulates RNA transcription, splicing and mitosis. Casein kinase 2 (CK2) is a survival protein kinase that suppresses cancer cell death. Eliminating the expression of these genes has potential therapeutic utility for breast cancer.
  
  
  METHODS
  Expression levels of CDK11 and CK2 mRNAs and associated proteins were examined in breast cancer cell lines and tissue arrays. RNA expression levels of CDC2L1, CDC2L2, CCNL1, CCNL2, CSNK2A1, CSNK2A2, and CSNK2B genes in breast cancer subtypes were analyzed. Effects following transfection of siRNAs against CDK11 and CK2 in cultured cells were examined by viability and clonal survival assays and by RNA and protein measures. Uptake of tenfibgen (TBG) nanocapsules by TNBC cells was analyzed by fluorescence-activated cell sorting. TBG nanocapsules delivered siRNAs targeting CDK11 or CK2 in mice carrying TNBC xenograft tumors. Transcript cleavage and response parameters were evaluated.
  
  
  RESULTS
  We found strong CDK11 and CK2 mRNA and protein expression in most human breast cancer cells. Immunohistochemical analysis of TNBC patient tissues showed 100% of tumors stained positive for CDK11 with high nuclear intensity compared to normal tissue. The Cancer Genome Atlas analysis comparing basal to other breast cancer subtypes and to normal breast revealed statistically significant differences. Down-regulation of CDK11 and/or CK2 in breast cancer cells caused significant loss of cell viability and clonal survival, reduced relevant mRNA and protein expression, and induced cell death changes. TBG nanocapsules were taken up by TNBC cells both in culture and in xenograft tumors. Treatment with TBG- siRNA to CDK11 or TBG- siRNA to CK2αα' nanocapsules induced appropriate cleavage of CDK11 and CK2α transcripts in TNBC tumors, and caused MDA-MB-231 tumor reduction, loss of proliferation, and decreased expression of targeted genes.
  
  
  CONCLUSIONS
  CDK11 and CK2 expression are individually essential for breast cancer cell survival, including TNBC. These genes serve as promising new targets for therapeutic development in breast cancer.
authors.affiliation: Research Service (151), Minneapolis VA Health Care System, One Veterans Drive, Minneapolis, MN 55417 USA ; Department of Laboratory Medicine and Pathology, University of Minnesota, 420 Delaware Street, SE, Minneapolis, MN USA ; Masonic Cancer Center, University of Minnesota, 717 Delaware Street SE Room 130, Minneapolis, MN 55414 USA.
authors.forename: Betsy T
authors.initials: BT
authors.lastname: Kren
authors.affiliation: GeneSegues Inc, 3180 High Point, Chaska, MN 55318 USA.
authors.forename: Gretchen M
authors.initials: GM
authors.lastname: Unger
authors.affiliation: Research Service (151), Minneapolis VA Health Care System, One Veterans Drive, Minneapolis, MN 55417 USA ; Department of Laboratory Medicine and Pathology, University of Minnesota, 420 Delaware Street, SE, Minneapolis, MN USA.
authors.forename: Md J
authors.initials: MJ
authors.lastname: Abedin
authors.affiliation: Masonic Cancer Center, University of Minnesota, 717 Delaware Street SE Room 130, Minneapolis, MN 55414 USA.
authors.forename: Rachel I
authors.initials: RI
authors.lastname: Vogel
authors.affiliation: Department of Laboratory Medicine and Pathology, University of Minnesota, 420 Delaware Street, SE, Minneapolis, MN USA ; Minnesota Supercomputing Institute, University of Minnesota, 117 Pleasant Street SE, Minneapolis, MN 55455 USA.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Henzler
authors.affiliation: Research Service (151), Minneapolis VA Health Care System, One Veterans Drive, Minneapolis, MN 55417 USA ; Department of Laboratory Medicine and Pathology, University of Minnesota, 420 Delaware Street, SE, Minneapolis, MN USA ; Masonic Cancer Center, University of Minnesota, 717 Delaware Street SE Room 130, Minneapolis, MN 55414 USA ; Department of Urology, University of Minnesota, 420 Delaware St. SE, Minneapolis, MN 55455 USA.
authors.forename: Khalil
authors.initials: K
authors.lastname: Ahmed
authors.affiliation: Research Service (151), Minneapolis VA Health Care System, One Veterans Drive, Minneapolis, MN 55417 USA ; Department of Laboratory Medicine and Pathology, University of Minnesota, 420 Delaware Street, SE, Minneapolis, MN USA ; Masonic Cancer Center, University of Minnesota, 717 Delaware Street SE Room 130, Minneapolis, MN 55414 USA.
authors.forename: Janeen H
authors.initials: JH
authors.lastname: Trembley
mesh_terms: D000818:Animals; D047390:Casein Kinase II / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002470:Cell Survival / Q000235:genetics; D018844:Cyclin-Dependent Kinases / Q000235:genetics* / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D015870:Gene Expression; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D015316:Genetic Therapy; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D053769:Nanocapsules; D011485:Protein Binding; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics*; D034743:RNA-Induced Silencing Complex; D015398:Signal Transduction; D064726:Triple Negative Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology / Q000628:therapy; D047368:Tumor Burden / Q000235:genetics; D023041:Xenograft Model Antitumor Assays
chemical_list: D053769:Nanocapsules; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D034743:RNA-Induced Silencing Complex; D047390:Casein Kinase II; C584437:CDK19 protein, human; D018844:Cyclin-Dependent Kinases
references.citation: Clin Pharmacol Ther. 2010 May;87(5):543-52
references.pmid: 20237469
references.citation: Biofactors. 2010 May-Jun;36(3):187-95
references.pmid: 20533398
references.citation: Breast Cancer Res. 2010;12(4):R56
references.pmid: 20663194
references.citation: Mol Carcinog. 2010 Nov;49(11):935-43
references.pmid: 20721974
references.citation: Cancer Metastasis Rev. 2010 Dec;29(4):595-606
references.pmid: 20814719
references.citation: Nat Biotechnol. 2010 Dec;28(12):1248-50
references.pmid: 21139605
references.citation: Cancer Res. 2010 Dec 15;70(24):10288-98
references.pmid: 21159648
references.citation: J Biol Chem. 2011 Jan 7;286(1):147-59
references.pmid: 21044963
references.citation: PLoS One. 2011;6(1):e14600
references.pmid: 21297952
references.citation: Eur J Cancer. 2011 Mar;47(5):792-801
references.pmid: 21194925
references.citation: Nat Med. 2011 Mar;17(3):313-9
references.pmid: 21386835
references.citation: Nature. 2011 May 19;473(7347):337-42
references.pmid: 21593866
references.citation: Cancer Lett. 2014 Jan 1;342(1):104-12
references.pmid: 24007862
references.citation: Proc Natl Acad Sci U S A. 2013 Dec 17;110(51):20681-6
references.pmid: 24297901
references.citation: Oncogene. 2014 Jan 2;33(1):108-15
references.pmid: 23178491
references.citation: Nature. 2014 May 29;509(7502):582-7
references.pmid: 24870543
references.citation: Nat Med. 2011 Jul;17(7):867-74
references.pmid: 21706029
references.citation: Mol Cell Biochem. 2011 Oct;356(1-2):21-35
references.pmid: 21761204
references.citation: Cancer Lett. 2012 Feb 1;315(1):48-58
references.pmid: 22050909
references.citation: Cancer Res. 2012 Feb 1;72(3):757-68
references.pmid: 22147262
references.citation: Nat Chem Biol. 2012 Mar;8(3):262-9
references.pmid: 22267120
references.citation: Clin Cancer Res. 2012 Sep 1;18(17):4580-8
references.pmid: 22791884
references.citation: Mol Cell Biol. 2012 Nov;32(22):4691-704
references.pmid: 22988298
references.citation: Cell Rep. 2012 Nov 29;2(5):1068-76
references.pmid: 23122962
references.citation: Oncogene. 2013 Mar 14;32(11):1373-83
references.pmid: 22562247
references.citation: Biochem Pharmacol. 2013 May 1;85(9):1219-26
references.pmid: 23435357
references.citation: Development. 2013 Aug;140(15):3079-93
references.pmid: 23861057
references.citation: PLoS One. 2013;8(10):e76247
references.pmid: 24098452
references.citation: J Biol Chem. 2002 Jul 12;277(28):25465-73
references.pmid: 11980906
references.citation: Cancer Res. 2002 Nov 1;62(21):6211-7
references.pmid: 12414649
references.citation: J Biol Chem. 2003 Jan 24;278(4):2265-70
references.pmid: 12429741
references.citation: J Biol Chem. 2003 Mar 7;278(10):8623-9
references.pmid: 12501247
references.citation: Mol Cancer Ther. 2014 Aug;13(8):2018-29
references.pmid: 24867250
references.citation: Nat Rev Cancer. 2014 Sep;14(9):611-22
references.pmid: 25118602
references.citation: Oncotarget. 2014 Aug 15;5(15):6484-96
references.pmid: 25153725
references.citation: PLoS One. 2014;9(10):e109970
references.pmid: 25333839
references.citation: Int J Biochem Cell Biol. 1999 Sep;31(9):941-9
references.pmid: 10533285
references.citation: Mol Cell. 2000 Apr;5(4):597-605
references.pmid: 10882096
references.citation: Histol Histopathol. 2001 Apr;16(2):573-82
references.pmid: 11332713
references.citation: Oncogene. 2001 May 31;20(25):3247-57
references.pmid: 11423974
references.citation: Neuron. 2001 Oct 25;32(2):277-87
references.pmid: 11683997
references.citation: J Biol Chem. 2002 Jan 25;277(4):2589-96
references.pmid: 11709559
references.citation: Mol Cell Biochem. 2001 Nov;227(1-2):153-65
references.pmid: 11827167
references.citation: Trends Cell Biol. 2002 May;12(5):226-30
references.pmid: 12062170
references.citation: FASEB J. 2003 Mar;17(3):349-68
references.pmid: 12631575
references.citation: J Biol Chem. 2004 Feb 6;279(6):4612-24
references.pmid: 14623875
references.citation: Curr Cancer Drug Targets. 2004 Feb;4(1):77-84
references.pmid: 14965269
references.citation: J Biol Chem. 2004 Mar 19;279(12):11639-48
references.pmid: 14684736
references.citation: Mol Cell Biol. 2004 Apr;24(8):3188-97
references.pmid: 15060143
references.citation: Neoplasia. 2004 Jan-Feb;6(1):1-6
references.pmid: 15068665
references.citation: Prog Nucleic Acid Res Mol Biol. 2004;77:263-88
references.pmid: 15196895
references.citation: J Biol Chem. 1993 Feb 5;268(4):2542-53
references.pmid: 7679097
references.citation: J Biol Chem. 1994 Jun 3;269(22):15786-94
references.pmid: 8195233
references.citation: Mol Med. 1995 Sep;1(6):659-66
references.pmid: 8529132
references.citation: Cancer Lett. 1996 Mar 19;101(1):31-5
references.pmid: 8625279
references.citation: J Cell Sci. 1998 Jun;111 ( Pt 11):1495-506
references.pmid: 9580558
references.citation: Electrophoresis. 1999 Feb;20(2):391-408
references.pmid: 10197447
references.citation: Br J Cancer. 2005 Feb 28;92(4):770-4
references.pmid: 15700036
references.citation: Nat Cell Biol. 2005 Jun;7(6):591-600
references.pmid: 15864305
references.citation: EMBO Rep. 2006 Apr;7(4):418-24
references.pmid: 16462731
references.citation: Proc Natl Acad Sci U S A. 2006 Oct 10;103(41):15079-84
references.pmid: 17005722
references.citation: Eur J Cancer. 2007 Mar;43(5):928-34
references.pmid: 17267203
references.citation: Nature. 2007 Mar 15;446(7133):329-32
references.pmid: 17361185
references.citation: J Cell Sci. 2007 Jul 15;120(Pt 14):2424-34
references.pmid: 17606997
references.citation: Cancer Lett. 2007 Dec 8;258(1):1-8
references.pmid: 17923280
references.citation: Biotechnol Bioeng. 2008 Mar 1;99(4):975-85
references.pmid: 17929316
references.citation: J Cell Biol. 2008 Mar 10;180(5):867-75
references.pmid: 18316407
references.citation: J Biol Chem. 2008 Mar 21;283(12):7721-32
references.pmid: 18216018
references.citation: Mol Cell Biochem. 2008 Sep;316(1-2):91-7
references.pmid: 18574673
references.citation: Nature. 2008 Dec 18;456(7224):971-5
references.pmid: 19011615
references.citation: J Clin Invest. 2009 Jul;119(7):2086-99
references.pmid: 19509468
references.citation: Cell Mol Life Sci. 2009 Jun;66(11-12):1858-67
references.pmid: 19387548
references.citation: Nat Cell Biol. 2009 Nov;11(11):1275-6
references.pmid: 19884882
references.citation: Biochim Biophys Acta. 2010 Mar;1804(3):499-504
references.pmid: 19665589
references.citation: Biochim Biophys Acta. 2010 Mar;1804(3):484-92
references.pmid: 19796713
references.citation: Clin Cancer Res. 2010 Apr 15;16(8):2295-307
references.pmid: 20371694