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Objective Theaquaporins(AQPs)areplasmamembranewater-transportingproteins.OurstudiesaimsatcomparedifferenttypesoflungcancerinthemolecularlevelbetweenAQP1、3and5expressionandlungcancercellswithdifferentexpressionofAQPswereusedtostudycellproliferationandmigration,twoimportantparametersfortumourcellbiology.Expectfurtherobtainedlungcancertissuebysurgery,wewonderedifhaveaninteractionbetweenAQPsandEGFRinqualitativeandquantitativeexpression,sothatfromthedeepunderstandingoflungcancerpathogenesis,thatinhibitionofAQPscouldbeapotentialnewtherapeutictargetagainsttumourgrowthandmetastasis.Currently,thedefinitivediagnosisoflungcancerdependsonhistologicconfirmationbybiopsyorsurgery.Whencomparedwithconventionalblindandrandombiopsies, magneticresonance(MR)image-guidedbiopsiesofsuspiciouslesionswereshownwithincreasedaccuracyandyield.Clearly,thekeytothesuccessofthistargetedbiopsyisthatMRimagesshouldhavehighersensitivityandspecificityinidentifyingsuspiciouslesions.Tothisend,anadvancedAQPMRimagingparadigmisnormallyusedtoobtainbothanatomicalandfunctionalimagestoincreasetheaccuarcyoflesionsdetection. Therehasbeenaresurgentinterestinintravoxelincoherentmotion(IVIM)MRimagingtoobtainperfusionaswellasdiffusioninformationonlesions,inwhichthediffusionwasmodeledasGaussiandiffusion.However,itwasobservedthatthisdiffusiondeviatedfromexpectedmonoexponentialdecayathighb-valuesandthereportedperfusioninlungiscontrarytothefindingsin dynamiccontrast-enhanced(DCE)MRIstudiesandangiogenesis.Thus,thisworkistoevaluatetheeffectofdifferentb-valueson IVIMperfusionfractions(f)anddiffusioncoefficients(D)forlungcancerdetection.Theresultsshowthatbothparameters dependedheavilyontheb-values,andthosederivedwithoutthehighestb-valuecorrelatedbestwiththeresultsfromDCE-MRI studies. Methods LungcancercelllinesderivedfromlungepitheliaincludingA549、HCC827andH358fortumourcellmigration,invasionassaysandwound-healingassay,comparisonofdifferentlungcancercellsinvasion,migration,anddamagerepairability.Cellmigrationandinvasionweremeasuredover12hand1×104cellswerestainedwithcrystalvioletforvisualization,wound-healingassaywasalsousedtoevaluatecellmigrationof24haftercellscratching;1×106cellswereinjectedintonudemicethroughtherightshoulder.Miceweresacrificedafter2and4weeks,andtumortissuewereharvestedforAQPsimmunofluorescencestainingandwesternblot,comparingexpressionofAQP1、3and5indifferenttypesoflungcancer; tumortissuesgrowto300-400mm3sizeforMReDWIimagingusingGE3.0T.ThefollowingparameterswereusedinDW-MRI:a single-shotspin-echoecho-planarimagingsequence,repetitiontimeandechotimeof4584and59ms;fieldofview(Anterior-Posterior(AP)/Right-Left(RL)/Foot-Head(FH))of160/180/60mm;20imageslices;areconstructedvoxelsizeof0.55x0.55x3.00 mm3(fromacquired1.25x1.25x3.00mm3);amaximumgradientstrengthof80mT/m(withgradientoverpluson);eighteendifferentDWgradientfactors,respectively0,50,100,150,200,300,500,800,1000,1300,1500,1700,2000,2500,3000,3500,4000, 4500s/mm2thenapplicationsGE4.6post-processingworkstationsoftwaretomeasuredADCvalues.Allmeasurementsareshownasmean6standarddeviation(SD),andDandfwithdifferentb-values.AStudentspairedt-test withatwo-taildistributionwasusedtoevaluatethedifferencetumortissuesforeachmeasure;thestatisticalsignificancewasconsideredatP<0.05.Scatterplotswereusedtoshowacorrelationbetweentwoparameters;beyondthat,anerror(ordata) ellipse(with95%confidencelevel)wasalsoincludedtohighlightdataclusteringintwodimensions.Thecentroidposition,area,andorientationoftheellipseweredeterminedbythemeans,thestandarddeviations,andthecorrelationcoefficientofthetwoparameters,respectively.Generally,theareaofanellipsecouldbeconsideredasafigureofmeritfordatacompactness. Results thefluorescentimmunohistochemicalresultsshowedthatinlungcancercelllineshavetheexpressionofAQP1、3and5,includingtotalAQPexpressofHCC827groupwasobviouslyhigherthantheothertwogroupsinvitro.andtheexpressionoftotalAQPHCC827groupwasobviouslyhigherthanthatofA549groupinorganizationallevel.WesternblotresultsshowHCC827grouphadasignificantlyhigherproteinexpressionofAQP1H358group,theexpressionofAQP3isnotstatistically significant,whiletheexpressionofAQP5belowHCC827group,buttotalHCC827AQPexpressionissignificantlyhigherthanH358group.TranswellexperimentsfurtherconfirmedthatbetweenthedifferenttypesofEGFRexpressioninlungcancerandtumorinvasionandmigrationhavecertainrelevance,andalsothereisalinkbetweencelldamagerepairability.Post-processing ofmagneticresonanceimagingHCC827ADCvaluesofthegroupandtherearesomedifferencesbetweenA549group.Insummary,IVIM-derivedparametersdependedheavilyonthechoiceofb-values;particularly,thetumorperfusionfraction(f)couldbeeithersignificantlyelevatedorindistinguishablefromnormaldependingontheexclusionorinclusionofthehigherbvalues. Conclusion DW-MRIhasbeenacceptedasanimagingbiomarkerofcancerandisregardedasakeytoolforthedetectionandcharacterizationofcancers,aswellasamethodformonitoringtheeffectsoftreatment.Traditionally,ADCwasderivedfromtheassumptionthattheobservedwaterdiffusionwassimplyarandommolecularprocessandwaslowerinlungcancerwhencomparedwithnormallungtissue.DifferenttypesoflungcancercellsAQPexpressdifferent;AQPexpressionhasacertainrelationshipwithcellinvasionandmigration;DifferentlungtumorcellsofMRDWIimaginggetADCvaluesisdifferent,andassociatedwithEGFRlungcancertypes.Tosumup,theADCvaluesoflungcancerhistologicaltypeshavecertainsignificance.