摘要
Objective:PyruvatekinasesM(PKM),includingthePKM1andPKM2isoforms,arecriticalfactorsinglucosemetabolism.PKM2promotesaerobicglycolysis,aphenomenonknownas"theWarburgeffect".ThepurposeofthisstudywastoidentifytherolesofPKM2inregulatingcellularmetabolism.Methods:TheCRISPR/Cas9systemwasusedtogeneratethePKM-knockoutcellmodeltoevaluatetheroleofPKMincellularmetabolism.LactatelevelsweremeasuredbytheVitrosLACslidemethodonanautoanalyzerandglucoselevelsweremeasuredbytheautoanalyzerAU5800.Themetabolismof13C6-glucoseor13C5-glutaminewasevaluatedbyliquidchromatography/massspectrometryanalyses.TheeffectsofPKMontumorgrowthweredetectedinvivoinatumor-bearingmousemodel.Results:WefoundthatbothPKM1andPKM2enabledaerobicglycolysis,butPKM2convertedglucosetolactatemuchmoreefficientlythanPKM1.Asaresult,PKM2reducedglucoselevelsreservedforintracellularutilization,particularlyfortheproductionofcitrate,andthusincreasedtheα-ketoglutarate/citrateratiotopromotethegenerationofglutamine-derivedacetylcoenzymeAthroughthereductivepathway.Furthermore,reductiveglutaminemetabolismfacilitatedcellproliferationunderhypoxiaconditions,whichsupportsinvivotumorgrowth.Inaddition,PKM-deletioninducedareverseWarburgeffectintumorassociatedstromalcells.Conclusions:PKM2playsacriticalroleinpromotingreductiveglutaminemetabolismandmaintainingprotonhomeostasis.ThisstudyishelpfultoincreasetheunderstandingofthephysiologicalroleofPKM2incancercells.
出版日期
2018年04月14日(中国期刊网平台首次上网日期,不代表论文的发表时间)