crabp2对肺癌细胞增殖的影响及其机制分析word格式论文.docxVIP

够降低MAPKs通路中的SAPK/JNK及其下游底物c-JUN的表达及磷酸化水平，而在不表达CRABP2的A549细胞中高表达CRABP2后这些分子的表达和磷酸化水平也相应提高；(2) 干扰CRABP2后，NF-κB p65的表达没有明显变化，但其468位和 536位丝氨酸的磷酸化水平减弱，而在A549细胞中未能检测到536位丝氨酸的磷酸化，高表达CRABP2后NF-κBp65的表达及468位的磷酸化也未出现明显上调，这可能是细胞个体的本底差异；(3) 干扰CRABP2的表达可以降低95-D细胞中 Cyclin E、Cyclin A和CDK4的表达，在A549细胞中高表达CRABP2后，这些因子的表达也相应上调。综合本研究结果，表明CRABP2的表达可以增强肺癌细胞对ATRA的敏感性，提高其抑癌效应；同时还可能通过SAPK/JNK—c-JUN和NF-κB信号途径调节肺癌细胞的增殖；提示了CRABP2在肿瘤中的双向调控作用。关键词CRABP2；全反式视黄酸；肺癌细胞增殖；MAPKs信号通路；NF-κB信号通路VTHE EFFECTAND MECHANISM OF CRABP2ON LUNG CANCER CELLPROLIFERATIONAbstractCellularretinoicacidbindingprotein2(CRABP2)isacytosol-to-nuclear shuttlingprotein,whichfacilitatesretinoicacidbindingtoitscognatereceptor complex(RAR.RXR)andtransfertothenucleus.Itisinvolvedintheretinoid signalingpathway.Retinoicacidanditsderivativeall-transretinoicacid(ATRA) areusefulpharmacologicalagentsincancer therapy and prevention.Inthis study,weinvestigatedtheeffectofCRABP2onlungcancercellresponseto ATRAand cell proliferation and the mechanisms involved.ByReal-timePCRandWesternBlottesting,wefoundthat95-Dlung cancercellhadgreaterCRABP2expressionthanA549lungcancercell. CRABP2mRNAin95-Dcellwasabout15foldofthatinA549cell,andwhich proteinwasundetectableinA549cellbyWesternBlot.Cellsweretreatedwith ATRAtotesttheirsensitivitytoATRA.AftertreatmentwithATRAindifferent concentrationsfor48h,proliferationofbothcellswereinhibited,andinhibiton beingstrongerathigherATRAconcentrations.Whileatasameconcentration, theinhibitoryeffectofATRAon95-DwasmuchstrongerthanonA549cell. CRABP2wasknockeddownbyRNAitoanalyzeitsroleinthesensitivityof 95-DcelltoATRA.KnockdownofCRABP2observablyreducedtheinhibitory effectofATRAon95-Dcell.Aftertreatedwith5μMATRAfor48h,the proliferationinhibitoryrateofControl-siRNAgroupandCRABP2-siRNAgroup were (26.09±3.68)% and (14.37±3.97)%repectively (P0.01).Meanwhile,wefoundthatknockdownofCRABP2mightdirectlyinhibitVI95-Dcellproliferation,whichresultedinanincreaseofcellportioninG1phase, anddecreasecellsinSphase.Toinvestigatethemechanismsinv