title: Discovery of selective inhibitors against EBNA1 via high throughput in silico virtual screening.
abstract: BACKGROUND
  Epstein-Barr Virus (EBV) latent infection is associated with several human malignancies and is a causal agent of lymphoproliferative diseases during immunosuppression. While inhibitors of herpesvirus DNA polymerases, like gancyclovir, reduce EBV lytic cycle infection, these treatments have limited efficacy for treating latent infection. EBNA1 is an EBV-encoded DNA-binding protein required for viral genome maintenance during latent infection.
  
  
  METHODS
  Here, we report the identification of a new class of small molecules that inhibit EBNA1 DNA binding activity. These compounds were identified by virtual screening of 90,000 low molecular mass compounds using computational docking programs with the solved crystal structure of EBNA1. Four structurally related compounds were found to inhibit EBNA1-DNA binding in biochemical assays with purified EBNA1 protein. Compounds had a range of 20-100 microM inhibition of EBNA1 in fluorescence polarization assays and were further validated for inhibition using electrophoresis mobility shift assays. These compounds exhibited no significant inhibition of an unrelated DNA binding protein. Three of these compounds inhibited EBNA1 transcription activation function in cell-based assays and reduced EBV genome copy number when incubated with a Burkitt lymphoma cell line.
  
  
  CONCLUSIONS
  These experiments provide a proof-of-principle that virtual screening can be used to identify specific inhibitors of EBNA1 that may have potential for treatment of EBV latent infection.
authors.affiliation: Drug Discovery and Design Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Scott
authors.initials: S
authors.lastname: Thompson
authors.forename: David C
authors.initials: DC
authors.lastname: Schultz
authors.forename: Weiliang
authors.initials: W
authors.lastname: Zhu
authors.forename: Hualiang
authors.initials: H
authors.lastname: Jiang
authors.forename: Cheng
authors.initials: C
authors.lastname: Luo
authors.forename: Paul M
authors.initials: PM
authors.lastname: Lieberman
mesh_terms: D002051:Burkitt Lymphoma; D045744:Cell Line, Tumor; D003198:Computer Simulation; D004247:DNA / Q000378:metabolism; D055808:Drug Discovery / Q000379:methods*; D004353:Drug Evaluation, Preclinical / Q000379:methods; D020031:Epstein-Barr Virus Infections / Q000188:drug therapy*; D019309:Epstein-Barr Virus Nuclear Antigens / Q000187:drug effects*; D004854:Herpesvirus 4, Human; D006801:Humans; D011485:Protein Binding / Q000187:drug effects; D014158:Transcription, Genetic / Q000187:drug effects*; D014764:Viral Proteins / Q000037:antagonists & inhibitors*
chemical_list: D019309:Epstein-Barr Virus Nuclear Antigens; D014764:Viral Proteins; D004247:DNA; C417029:EBV-encoded nuclear antigen 1
references.citation: Cell. 1996 Mar 8;84(5):791-800
references.pmid: 8625416
references.citation: Rev Med Virol. 2000 Mar-Apr;10(2):83-100
references.pmid: 10713596
references.citation: Chem Biol. 2006 Jul;13(7):745-51
references.pmid: 16873022
references.citation: Cell. 1995 Oct 6;83(1):39-46
references.pmid: 7553871
references.citation: Proteins. 1998 Oct 1;33(1):74-87
references.pmid: 9741846
references.citation: Cell. 1985 Oct;42(3):859-68
references.pmid: 2996781
references.citation: J Chem Inf Model. 2005 Jan-Feb;45(1):177-82
references.pmid: 15667143
references.citation: J Mol Biol. 1998 Dec 18;284(5):1273-8
references.pmid: 9878348
references.citation: N Engl J Med. 2004 Mar 25;350(13):1328-37
references.pmid: 15044644
references.citation: J Biol Chem. 2008 May 9;283(19):12819-30
references.pmid: 18337247
references.citation: J Virol. 1990 May;64(5):2369-79
references.pmid: 2157891
references.citation: Virology. 2006 Mar 15;346(2):385-93
references.pmid: 16343579
references.citation: Nature. 1985 Feb 28-Mar 6;313(6005):812-5
references.pmid: 2983224
references.citation: J Biol Chem. 2002 Jul 26;277(30):27401-11
references.pmid: 12015325
references.citation: Proc Natl Acad Sci U S A. 2003 Nov 25;100(24):14269-74
references.pmid: 14603034
references.citation: J Med Chem. 2003 Jun 19;46(13):2656-62
references.pmid: 12801229
references.citation: EMBO J. 2005 Apr 6;24(7):1406-17
references.pmid: 15775975
references.citation: Mol Cell Biol. 2006 Feb;26(3):1124-34
references.pmid: 16428463
references.citation: J Comput Aided Mol Des. 2002 Dec;16(12):883-902
references.pmid: 12825621
references.citation: J Med Chem. 2003 Jun 5;46(12):2287-303
references.pmid: 12773034
references.citation: Proc Natl Acad Sci U S A. 2007 May 1;104(18):7391-6
references.pmid: 17463090
references.citation: Proc Natl Acad Sci U S A. 2003 Sep 16;100(19):10989-94
references.pmid: 12947043
references.citation: Nat Rev Cancer. 2004 Oct;4(10):757-68
references.pmid: 15510157
references.citation: Anal Biochem. 2005 May 15;340(2):259-71
references.pmid: 15840499
references.citation: Bioorg Med Chem Lett. 2007 Oct 15;17(20):5652-5
references.pmid: 17766109
references.citation: Proc Natl Acad Sci U S A. 2006 Sep 19;103(38):14188-93
references.pmid: 16966603