简介:背景:国内外研究表明,自噬与激素性股骨头缺血坏死之间具有一定的相关性,控制PI3K/Akt/mTOR信号通路可能调控自噬,对该病具有一定的治疗作用。目的:通过介绍PI3K/Akt/mTOR信号通路对自噬的调控以及自噬与激素性股骨头缺血坏死的关系,总结并讨论自噬在激素性股骨头缺血坏死中的最新研究进展。方法:检索PubMed数据库、Webofscience数据库、万方数据库中2008至2018年相关文献,检索词分别为“Steroid,necrosisofthefemoralhead,autophagy,signalpathway,糖皮质激素,股骨头坏死,自噬”。排除较陈旧及重复的文献,通过整理,共纳入83篇文献进行分析探讨。结果与结论:①PI3K/Akt/mTOR信号通路为抑制性通路,可以负向调控自噬,激活该通路可以抑制自噬,相反,抑制该通路可以诱导自噬;②激素诱导细胞发生凋亡和自噬与其剂量有关,较低剂量的激素可以激活自噬,而较高剂量的激素会导致细胞凋亡;③自噬对于激素性股骨头缺血坏死是双向作用,正面作用是自噬有助于改善激素性股骨头缺血坏死,负面作用是自噬诱导了激素性股骨头缺血坏死并加速其恶化。
简介:目的探讨磷脂酰肌醇-3-激酶(PI3K)/蛋白激酶B(PKB,也称AKT)信号通路相关蛋白在食管癌组织中的表达情况,并分析其与食管癌淋巴结转移和淋巴管生成的关系。方法选取120例食管癌患者,收集经组织病理学检查证实的食管癌组织和癌旁正常黏膜组织。采用免疫组织化学法检测PI3K和AKT蛋白在食管癌组织及其相应癌旁正常黏膜组织中的表达情况;采用D2-40蛋白标记淋巴管,并采用免疫组织化学法检测微淋巴管密度(LMVD),分析PI3K、AKT蛋白的表达与食管癌患者临床特征及微淋巴管密度(LMVD)的关系。结果食管癌组织中PI3K和AKT蛋白的阳性表达率分别为85.0%和86.7%,均明显高于癌旁食管正常黏膜组织的4.2%和5.8%,差异均有统计学意义(P﹤0.01)。不同性别、组织分化程度食管癌患者食管癌组织中PI3K、AKT蛋白的阳性表达率比较,差异均无统计学意义(P﹥0.05)。有淋巴结转移、TNM分期为Ⅲ+Ⅳ期的食管癌患者食管癌组织中PI3K、AKT蛋白的阳性表达率均高于无淋巴结转移、TNM分期为Ⅰ+Ⅱ期的食管癌患者,差异均有统计学意义(P﹤0.05)。PI3K蛋白阳性表达食管癌组织中LMVD的数量为(13.92±3.02),明显高于PI3K蛋白阴性表达食管癌组织的(6.54±1.05),差异有统计学意义(P﹤0.01);AKT蛋白阳性表达食管癌组织中LMVD的数量为(13.84±3.08),明显高于AKT蛋白阴性表达食管癌组织的(6.14±0.89),差异有统计学意义(P﹤0.01)。结论PI3K/AKT信号通路相关蛋白在食管癌组织中的表达水平较高,且能够促进微淋巴管的生成和淋巴结转移,其表达情况与患者的临床特征也具有一定的关系。阻断该通路可作为治疗和预防食管癌及淋巴结转移的新的研究方向。
简介:Objective:ToexaminetheeffectofpSer9-GSK-3βonbreastcancerandtodeterminewhethertheunderlyingmetabolicandimmunologicalmechanismisassociatedwithROS/eIF2Bandnaturalkiller(NK)cells.Methods:WeemployedTWS119toinactivateGSK-3βbyphosphorylatingSer9andexploreditseffectonbreastcancerandNKcells.TheexpressionofGSK-3β,naturalkillergroup2memberD(NKG2D)ligands,eIF2BwasquantifiedbyPCRandWesternblot.Wemeasuredintracellularreactiveoxygenspecies(ROS)andmitochondrialROSusingDCFH-DAandMitoSOXTMprobe,respectively,andconductedquantitativeanalysisofcellularrespirationon4T1cellswithmitochondrialrespiratorychaincomplexⅠ/Ⅲkits.Results:OurinvestigationrevealedthatTWS119downregulatedNKG2Dligands(H60aandRae1),suppressedthecytotoxicityofNKcells,andpromotedthemigrationof4T1murinebreastcancercells.Nevertheless,LY290042,whichattenuatesp-GSK-3βformationbyinhibitingthePI3K/Aktpathway,reversedtheseeffects.WealsofoundthathigherexpressionofpSer9-GSK-3βinducedhigherlevelsofROS,andobservedthatabnormalityofmitochondrialrespiratorychaincomplexⅠ/ⅢfunctioninducedthedysfunctionofGSK-3β-inducedelectrontransportchain,naturallydisturbingtheROSlevel.Inaddition,theexpressionofNOX3andNOX4wassignificantlyup-regulated,whichaffectedthegenerationofROSandassociatedwiththemetastasisofbreastcancer.Furthermore,wefoundthattheexpressionofpSer535-eIF2BpromotedtheexpressionofNKG2Dligands(Mult-1andRae1)followingbyexpressionofpSer9-GSK-3βandgenerationofROS.Conclusions:ThePI3K/Akt/GSK-3β/ROS/eIF2BpathwaycouldregulateNKcellactivityandsensitivityoftumorcellstoNKcells,whichresultedinbreastcancergrowthandlungmetastasis.Thus,GSK-3βisapromisingtargetofanti-tumortherapy.
简介:Objective:ActivatingKRASmutationsarethemostcommondriversinthedevelopmentofnon-smallcelllungcancer(NSCLC).However,unsuccessoftreatmentbydirectinhibitionofKRAShasbeenproven.DeregulationofPI3KsignalingplaysanimportantroleintumorigenesisanddrugresistanceinNSCLC.TheactivityofPI3Kα-selectiveinhibitionagainstKRAS-mutatedNSCLCremainslargelyunknown.Methods:CellproliferationwasdetectedbysulforhodamineBassay.Cellcycledistributionandapoptosisweremeasuredbyflowcytometry.CellsignalingwasassessedbyWesternblotandimmunohistochemistry.RNAinterferencewasusedtodown-regulatetheexpressionofcyclinD1.HumanNSCLCxenograftswereemployedtodetecttherapeuticefficacyinvivo.Results:CYH33possessedvariableactivityagainstapanelofKRAS-mutatedNSCLCcelllines.AlthoughCYH33blockedAKTphosphorylationinalltestedcells,RbphosphorylationdecreasedinCYH33-sensitive,butnotinCYH33-resistantcells,whichwasconsistentwithG1phasearrestinsensitivecells.CombinedtreatmentwiththeCDK4/6inhibitor,PD0332991,andCYH33displayedsynergisticactivityagainsttheproliferationofbothCYH33-sensitiveandCYH33-resistantcells,whichwasaccompaniedbyenhancedG1-phasearrest.Moreover,down-regulationofcyclinD1sensitizedNSCLCcellstoCYH33.Reciprocally,CYH33abrogatedthePD0332991-inducedup-regulationofcyclinD1andphosphorylationofAKTinA549cells.Co-treatmentwiththesetwodrugsdemonstratedsynergisticactivityagainstA549andH23xenografts,withenhancedinhibitionofRbphosphorylation.Conclusions:SimultaneousinhibitionofPI3KαandCDK4/6displayedsynergisticactivityagainstKRAS-mutatedNSCLC.ThesedataprovideamechanisticrationaleforthecombinationofaPI3KαinhibitorandaCDK4/6inhibitorforthetreatmentofKRASmutatedNSCLC.
简介:摘要发电机出口断路器(GCB)是核电站向外发电的重要设备,目前世界上只有ABB和阿尔斯通能够制造生产百万机组级别的发电机出口断路器,但是由于巴基斯坦涉及出口受限,因此K-2K-3项目不能够购买第三国的产品,只能进行自主研发。由于研发进展受阻,不能满足项目的进度要求,因此决定采用替代方案,在满足核电站安全运行需求的前提下,保证工程的进度进行,本文就替代方案和管理理念进行了详细的介绍。
简介:目的探讨微小RNA-148a-3p(miR-148a-3p)对丝裂原活化蛋白激酶激酶激酶9(MAP3K9)的靶向调控作用及对胃癌细胞增殖和凋亡的影响。方法向对数生长期胃癌细胞株MGC-803转染miR-148a-3p模拟物(mimics组)和阴性对照(NC组),以未转染的MGC-803细胞为对照组;采用实时定量PCR(QPCR)检测各组miR-148a-3p水平以评价转染效率,MTT法检测各组细胞增殖能力,流式细胞术检测各组细胞凋亡情况,分别采用QPCR和Westernblotting检测Bcl-2、Bax、caspase-3及MAP3K9mRNA和蛋白水平,同时采用双荧光素酶报告实验验证miR-148a-3p与MAP3K9的靶向作用关系。结果QPCR结果显示,对照组、NC组和mimics组的miR-148a-3p水平分别为1.021±0.123、1.087±0.196和2.854±0.368,与对照组和NC组比较,mimics组的miR-148a-3p水平升高(P<0.05)。mimics组MGC-803细胞的增殖活力较其余两组减弱(P<0.05)。mimics组MGC-803细胞凋亡率为(15.2±1.6)%,高于对照组的(3.5±0.9%)%和NC组的(4.5±1.1)%,差异具有统计学意义(P<0.05)。与对照组和NC组比较,mimics组的MAP3K9和Bcl-2的mRNA和蛋白水平均下调,而Bax和caspase-3的mRNA和蛋白水平均上调(P<0.05);双荧光素酶报告实验证实MAP3K9是miR-148a-3p的直接作用靶点。结论MiR-148a-3p可抑制胃癌细胞MGC-803的增殖并诱导其凋亡,可能通过靶向MAP3K9来发挥抑癌作用,调控miR-148a-3p/MAP3K9轴在胃癌防治中有一定应用前景。
简介:RapamycintreatmenthasbeenshowntoincreaseautophagyactivityandactivateAktphosphorylation,suppressingapoptosisinseveralmodelsofischemiareperfusioninjury.However,littlehasbeenstudiedontheneuroprotectiveeffectsonspinalcordinjurybyactivatingAktphosphorylation.Wehypothesizedthatbotheffectsofrapamycin,theincreasedautophagyactivityandAktsignaling,wouldcontributetoitsneuroprotectiveproperties.Inthisstudy,acompressivespinalcordinjurymodelofratwascreatedbyananeurysmclipwitha30gclosingforce.Ratmodelswereintraperitoneallyinjectedwithrapamycin1mg/kg,followedbyautophagyinhibitor3-methyladenine2.5mg/kgandAktinhibitorIV1μg/kg.Westernblotassay,immunofluorescencestainingandterminaldeoxynucleotidyltransferase-mediateddUTPnickendlabelingassaywereusedtoobservetheexpressionofneuronalautophagymoleculeBeclin1,apoptosis-relatedmoleculesBcl-2,Bax,cytochromec,caspase-3andAktsignaling.OurresultsdemonstratedthatrapamycininhibitedtheexpressionofmTORininjuredspinalcordtissueandup-regulatedtheexpressionofBeclin1andphosphorylated-Akt.Rapamycinpreventedthedecreaseofbcl-2expressionininjuredspinalcordtissue,reducedBax,cytochromecandcaspase-3expressionlevelsandreducedthenumberofapoptoticneuronsininjuredspinalcordtissue24hoursafterspinalcordinjury.3-MethyladenineandAktinhibitorIVinterventionsuppressedtheexpressionofBeclin-1andphosphorylated-Aktininjuredspinalcordtissueandreducedtheprotectiveeffectofrapamycinonapoptoticneurons.TheaboveresultsindicatethattheneuroprotectiveeffectofrapamycinonspinalcordinjuryratscanbeachievedbyactivatingautophagyandtheAktsignalingpathway.
简介:Resistancetocisplatin(DDP)-basedchemotherapyisamajorcauseoftreatmentfailureinhumangastriccancer(GC).Itisnecessarytoidentifythedrugstore-sensitizeGCcellstoDDP.Inourpreviousresearch,ZuoJinWanFormula(ZJW)hasbeenprovedcouldincreasethemitochondrialapoptosisviacofilin-1inaimmortalizedcellline,SGC-7901/DDP.Duetotheimmortalizedcellsmaystilldifficulthighlyrecapitulatetheimportantmoleculareventsinvivo,primaryGCcellsmodelderivedfromclinicalpatientwasconstructedinthepresentstudytofurtherevaluatetheeffectofZJWandtheunderlyingmolecularmechanism.ImmunofluorescentstainingwasusedtoindentifyprimaryculturedhumanGCcells.Westernblottingwascarriedouttodetecttheproteinexpression.CellCountingKit-8(CCK-8)wasusedtoevaluatecellproliferation.Flowcytometryanalysiswasperformedtoassesscellapoptosis.ZJWinhibitedproliferationandinducedapoptosisinprimaryDDP-resistantGCcells.Notably,theapoptosisinGCcellswasmediatedbyinducingcofilin-1mitochondrialtranslocation,down-regulatingBcl-2andup-regulatingBaxexpression.Surprisingly,thelevelofp-AKTproteinwashigherinDDP-resistantGCcellsthanthatoftheDDP-sensitiveGCcells,andtheactivationofAKTcouldattenuateZJW-inducedsensitivitytoDDP.ThesedatarevealedthatZJWcanincreasethechemosensitivityinDDP-resistantprimaryGCcellsbyinducingmitochondrialapoptosisandAKTinactivation.ThecombiningchemotherapywithZJWmaybeaneffectivetherapeuticstrategyforGCchemoresistancepatients.
简介:Thenextgenerationofadvancedlightsourcesrequiresphotonswithlargeaveragefluxandhighbrightness,whichneedsadvancedelectrongunmatchedwithexcellentphotocathodematerials.K2CsSbphotocathodehastheadvantagesofhighquantumefficiency,longlifetimeandinstantaneousresponse.ThisstudyintroducesthedesignofasetofK2CsSbphotocathodepreparationsystemsanddetailedpreparationprocessofK2CsSbphotocathodes,includingsequentialdepositionprocessandco-depositionprocess,andfinallydevelopsaK2CsSbphotocathode.Theinfluenceoflaserpoweronthequantumefficiencyisalsoinvestigated.