Cancer Exosomes Perform Cell-Independent MicroRNA

CancerCellArticleCancerExosomesPerformCell-IndependentMicroRNABiogenesisandPromoteTumorigenesisSoniaA.Melo,1,2HikaruSugimoto,1,2JoyceT.O’Connell,2NoritoshiKato,2AlbertoVillanueva,3AugustVidal,4LeQiu,5EdwardVitkin,5LevT.Perelman,5CarlosA.Melo,6,7AnthonyLucci,8CristinaIvan,9GeorgeA.Calin,10andRaghuKalluri1,2,*1DepartmentofCancerBiology,MetastasisResearchCenter,UniversityofTexasMDAndersonCancerCenter,Houston,TX77054,USA2DivisionofMatrixBiology,DepartmentofMedicine,BethIsraelDeaconessMedicalCenterandHarvardMedicalSchool,Boston,MA02215,USA3TranslationalResearchLaboratory,CatalanInstituteofOncology,BellvitgeBiomedicalResearchInstitute(IDIBELL),L’HospitaletdeLlobregat,Barcelona08908,Spain4DepartmentofPathology,HospitalUniversitarideBellvitge,BellvitgeBiomedicalResearchInstitute(IDIBELL),L’HospitaletdeLlobregat,Barcelona08908,Spain5DepartmentofObstetrics,Gynecology,andReproductiveBiology,andDepartmentofMedicine,CenterforAdvancedBiomedicalImagingandPhotonics,BethIsraelDeaconessMedicalCenter,Boston,MA02215,USA6DivisionofGeneRegulation,TheNetherlandsCancerInstitute,Plesmanlaan121,1066CXAmsterdam,theNetherlands7DoctoralProgrammeinBiomedicineandExperimentalBiology,CentreforNeuroscienceandCellBiology,3004-517Coimbra,Portugal8DepartmentofSurgicalOncology,UniversityofTexasMDAndersonCancerCenter,Houston,TX77030,USA9CenterforRNAInterferenceandNon-codingRNAs,UniversityofTexasMDAndersonCancerCenter,Houston,TX77054,USA10DepartmentofExperimentalTherapeutics,UniversityofTexasMDAndersonCancerCenter,Houston,TX77054,USA*Correspondence:[e-mail](miRNAs)associatedwiththeRISC-LoadingComplex(RLC)anddisplaycell-independentcapacitytoprocessprecursormicroRNAs(pre-miRNAs)intomaturemiRNAs.Pre-miRNAs,alongwithDicer,AGO2,andTRBP,arepresentinexosomesofcancercells.CD43me-diatestheaccumulationofDicerspecificallyincancerexosomes.CancerexosomesmediateanefficientandrapidsilencingofmRNAstoreprogramthetargetcelltranscriptome.ExosomesderivedfromcellsandseraofpatientswithbreastcancerinstigatenontumorigenicepithelialcellstoformtumorsinaDicer-dependentmanner.Thesefindingsofferopportunitiesforthedevelopmentofexosomesbasedbiomarkersandtherapies.INTRODUCTIONExosomesarenano-vesiclesof50–140nminsizethatcontainproteins,mRNA,andmicroRNAs(miRNAs)protectedbyalipidbilayer(KahlertandKalluri,2013;Cocuccietal.,2009;SimonsandRaposo,2009;Simpsonetal.,2008;The´ryetal.,2002).Severalrecentstudiesdemonstratedthatexosomesaresecretedbymultiplecelltypes,includingcancercells,stemcells,immunecells,andneurons(The´ry,2011).Exosomeslevelsintheserumofbreastcancerpatientsaregenerallyhigherwhencomparedtonormalsubjects(Logozzietal.,2009;TaylorandGercel-Taylor,2008;O’Brienetal.,2013).miRNAsaresmallnoncodingRNAsof18–24nucleotides(nt)inlengththatcontrolgeneexpressionposttranscriptionally.TheyaresynthesizedviasequentialactionsofDroshaandDicerendo-nucleases,andincorporatewiththeRNAinducedsilencingcom-plex(RISC)totargetmRNAs(Bartel,2009;ManiatakiandMour-elatos,2005).RISC-loadedmiRNAsbindinasequence-specificmannertotargetmRNAs,initiatingtheirrepressionthroughacombinationoftranslationalinhibition,RNAdestabilization,orthroughdirectRISC-mediatedmRNAcleavage(Ambros,2004;Bartel,2009;Filipowicz,2005).ForamiRNAtobefunctionalandachieveefficientgenesilencing,itmustformacomplexwiththeRISC-loadingcomplex(RLC)proteinsDicer,TRBP,SignificanceBreastcancercellssecreteexosomeswithspecificcapacityforcell-independentmiRNAbiogenesis,whilenormalcell-derivedexosomeslackthisability.ExosomesderivedfromcancercellsandserumfrompatientswithbreastcancercontaintheRISCloadingcomplexproteins,Dicer,TRBP,andAGO2,whichprocesspre-miRNAsintomaturemiRNAs.Cancerexo-somesalterthetranscriptomeoftargetcellsinaDicer-dependentmanner,whichstimulatenontumorigenicepithelialcellstoformtumors.Thisstudyidentifiesamechanismwherebycancercellsimpartanoncogenicfieldeffectbymanipulatingthesurroundingcellsviaexosomes.PresenceofDicerinexosomesmayserveasbiomarkerfordetectionofcancer.CancerCell26,1–15,November10,2014ª2014ElsevierInc.1Pleasecitethisarticleinpressas:Meloetal.,CancerExosomesPerformCell-IndependentMicroRNABiogenesisandPromoteTumorigenesis,CancerCell(2014),(nm)54321001234512345543210MDA-MB-231ExosomesAB151050051015NMuMGExosomes4T1Exosomesr=0.4037C051015151050r=0.5612MCF10AExosomesMCF7Exosomes051015151050MCF10AExosomesMDA231Exosomesr=0.39244T1Exos_24h4T1Exos_72hMCF7Exos_24hMCF7Exos_72hMDA231Exos_24hMDA231Exos_72hIntensity-220MCF10AExosomes_72h151050MCF10AExosomes_24h051015r=0.9145MCF7Exosomes_72h151050MCF7Exosomes_24h051015r=0.5782NMuMGExosomes_72h151050NMuMGExosomes_24h051015r=0.93274T1Exosomes_72h1510504T1Exosomes_24h051015r=0.4833miR-10amiR-10bmiR-21miR-