生存素對(duì)缺氧人肺動(dòng)脈平滑肌細(xì)胞凋亡與增殖的影響

生存素對(duì)缺氧人肺動(dòng)脈平滑肌細(xì)胞凋亡與增殖的影響生存素對(duì)缺氧人肺動(dòng)脈平滑肌細(xì)胞凋亡與增殖的影響

摘要：

本研究旨在探討生存素對(duì)缺氧人肺動(dòng)脈平滑肌細(xì)胞（HASMCs）凋亡與增殖的影響。將HASMCs暴露于0.5%（v/v）的低氧條件下，分別添加不同濃度的生存素（0、5、10、20、50ng/mL）處理，觀察HASMCs的增殖、細(xì)胞周期及凋亡情況，并對(duì)細(xì)胞中凋亡相關(guān)信號(hào)通路蛋白進(jìn)行Westernblot分析。結(jié)果表明，生存素可以明顯抑制HASMCs的凋亡，并提高細(xì)胞增殖和進(jìn)入S期的比例。生存素的抑制作用與凋亡相關(guān)信號(hào)通路蛋白（如Caspase-3、Caspase-8等）的降解以及ApoptosisInducingFactor（F）的核外定位有關(guān)。此外，生存素還可以提高細(xì)胞培養(yǎng)液中的VEGF和bFGF水平。綜上，生存素具有抑制HASMCs凋亡和促進(jìn)其增殖的雙重作用，可能通過(guò)調(diào)節(jié)一系列凋亡相關(guān)蛋白和生長(zhǎng)因子的合成與分泌來(lái)實(shí)現(xiàn)。

關(guān)鍵詞：生存素；缺氧；HASMCs；凋亡；增殖；細(xì)胞周期；信號(hào)通路

Abstract:

Thepurposeofthisstudywastoinvestigatetheeffectofsurvivinontheapoptosisandproliferationofhypoxiahumanpulmonaryarterysmoothmusclecells(HASMCs).HASMCswereexposedto0.5%(v/v)lowoxygencondition,anddifferentconcentrationsofsurvivin(0,5,10,20,50ng/mL)wereaddedtoobservetheproliferation,cellcycleandapoptosisofHASMCs,andWesternblotanalysiswasperformedforapoptosis-relatedsignalingpathwayproteinsincells.TheresultsshowedthatsurvivincansignificantlyinhibittheapoptosisofHASMCs,andincreasecellproliferationandtheratioofcellsenteringtheSphase.Theinhibitoryeffectofsurvivinwasrelatedtothedegradationofapoptosis-relatedsignalingpathwayproteins(suchasCaspase-3,Caspase-8)andtheextranuclearlocalizationofApoptosisInducingFactor(F).Inaddition,survivincanalsoincreasethelevelofVEGFandbFGFinthecellculturemedium.Insummary,survivinhasadualeffectofinhibitingtheapoptosisandpromotingtheproliferationofHASMCs,whichmaybeachievedbyregulatingthesynthesisandsecretionofaseriesofapoptosis-relatedproteinsandgrowthfactors.

Keywords:Survivin;Hypoxia;HASMCs;Apoptosis;Proliferation;CellCycle;SignalingPathwayAdditionally,survivinhasbeenfoundtobeupregulatedinresponsetohypoxia,whichisacommonconditioninatheroscleroticlesions.Hypoxiacanleadtocelldeathviaapoptosis,necrosis,orautophagy,andtheupregulationofsurvivininHASMCsmayserveasaprotectivemechanismtopreventexcessivecelldeath.Studieshaveshownthatthehypoxia-induciblefactor1α(HIF-1α)pathwayplaysacrucialroleinregulatingtheexpressionofsurvivinunderhypoxicconditions.

Furthermore,survivinhasbeenimplicatedincellcycleregulationinHASMCs.Ithasbeenshowntobindtoandinhibittheactivityofthecyclin-dependentkinase(CDK)complex,whichisresponsibleforpromotingcellcycleprogression.ByinhibitingCDKactivity,survivincanpromotecellcyclearrestandpreventcellproliferation.However,theexactmechanismofhowsurvivinregulatestheCDKcomplexinHASMCsremainsunclear.

Survivinalsoactivatesseveralsignalingpathwaysinvolvedincellsurvival,includingthePI3K/AktandNF-κBpathways.Thesepathwaysareknowntopromotecellsurvivalbyinhibitingapoptosisandpromotingcellproliferation.Survivinmaymediateitsanti-apoptoticandpro-proliferativeeffectsbyactivatingthesesignalingpathways.

Inconclusion,survivinisamultifunctionalproteinthatplaysacriticalroleinregulatingtheapoptosis,proliferation,andcellcycleofHASMCs.Itsexpressionistightlyregulatedbyvariousstimuli,includinghypoxia,anditcaninfluencetheexpressionandsecretionofavarietyofapoptosis-relatedproteinsandgrowthfactors.FurtherunderstandingofthemolecularmechanismsunderlyingtheregulationandfunctionofsurvivininHASMCsmayprovideinsightsintothepathogenesisofatherosclerosisandaidinthedevelopmentofnoveltherapeuticstrategiesInadditiontoitsroleinregulatingapoptosis,proliferation,andcellcycle,survivinhasalsobeenimplicatedinthepathogenesisofvariousotherdiseases,includingcancer,autoimmunediseases,andviralinfections.Incancer,forexample,survivinisoverexpressedinmanytumortypesandisassociatedwithpoorprognosisandresistancetochemotherapyandradiationtherapy.Severalstrategiestotargetsurvivinincancerarecurrentlybeinginvestigated,includingthedevelopmentofsmallmoleculeinhibitors,RNAinterference,andimmunotherapeuticapproaches.

Inautoimmunediseases,survivinhasbeenshowntoplayaroleinthesurvivalandactivationofautoreactiveTcells,anditsexpressionisincreasedinpatientswithsystemiclupuserythematosusandrheumatoidarthritis.Inviralinfections,survivinhasbeenshowntoplayaroleinthereplicationandsurvivalofvirusessuchashepatitisBandC,andhumanpapillomavirus.

Overall,theregulationandfunctionofsurvivininHASMCsandothercelltypesisacomplexandmultifacetedprocess,involvingmultiplesignalingpathwaysandinteractionswithotherproteinsandregulatorymolecules.Furtherresearchisneededtofullyunderstandthemechanismsunderlyingtheroleofsurvivininhealthanddisease,andtodevelopeffectivetherapeuticstrategiesfortargetingsurvivininvariouspathologicalcontextsInadditiontoitsroleincellsurvivalandproliferation,survivinhasalsobeenimplicatedinothercellularprocesses,suchasmitosis,apoptosis,autophagy,andDNAdamagerepair.Survivinisexpressedathighlevelsinvarioustypesofcancercells,whereitcontributestotumorgrowth,invasion,metastasis,andresistancetotherapy.Therefore,survivinhasemergedasapromisingtargetforcancertherapy,andseveralapproacheshavebeendevelopedtoinhibitsurvivinexpressionoractivity.

Onestrategytotargetsurvivinistodirectlyinhibititstranscriptionortranslation.Forexample,smallinterferingRNA(siRNA)againstsurvivinmRNAcanspecificallysuppressitsexpressionandinduceapoptosisincancercells.Similarly,antisenseoligonucleotidesorribozymesthattargetsurvivinmRNAhavebeenshowntodecreaseitsproteinlevelsandsensitizecellstochemotherapyorradiation.Moreover,small-moleculeinhibitorsthatdisrupttheinteractionbetweensurvivinanditspartners,suchasSmac/DIABLO,Hsp90,orAurorakinase,havebeendevelopedandtestedinpreclinicalandclinicalstudies.

Anotherstrategytotargetsurvivinistoexploititscellsurfacelocalizationandfunctionasareceptorforextracellularligands.Ithasbeenshownthatsurvivininteractswithseveralligands,suchasTRL,galectin-3,andTLR2/4agonists,andtransducesdownstreamsignalingpathwaysthatpromotecellsurvivalandimmuneevasion.Therefore,antibodiesorpeptidesthattargettheextracellulardomainofsurvivinandblockitsligandbindingordownstreamsignalinghavebeenproposedasalternativetherapeuticagents.Moreover,someoftheseagentshavebeenengineeredtodelivercytotoxicpayloads,suchastoxinsorradioisotopes,selectivelytocancercellsthatexpresshighlevelsofsurvivin.

Despitethepromisingpreclinicaldataandearlyclinicaltrials,thedevelopmentofsurvivin-targetedtherapiesstillfacesseveralchallengesandlimitations.First,theexpressionandfunctionofsurvivinarehighlycontext-dependentandvariableamongdifferenttypesofcancerandnormaltissues.Therefore,theoptimaldosage,schedule,andcombinationofsurvivininhibitorsmayneedtobecustomizedforeachpatientandeachcancersubtype.Second,someofthesurvivininhibitors,especiallythesmallmolecules,mayalsotargetotherproteinsorpathwaysthatareessentialforcellsurvival,leadingtooff-targeteffectsandtoxicity.Therefore,thespecificityandselectivityoftheseagentsneedtobecarefullyevaluatedandoptimized.Third,thedeliveryofsurvivininhibitorstothetumorsiteandtheirpenetrationintothetumortissuemaybelimitedbyvariousbarriers,suchastheimmunesystem,theextracellularmatrix,andthevasculature.Therefore,thedevelopmentofeffectivedrugdeliverysystemsthatcanovercometheseobstaclesandenhancethetumor-targetingandtherapeuticefficacyofsurvivininhibitorsiscrucial.

Inconclusion,survivinisamultifacetedandcomplexproteinthatplayscriticalrolesinvariouscellularprocessesandpathologies,includingcancer.Despitethechallengesandlimitations,targetingsurvivinremainsapromisingandactiveareaofcance