简介：AIM:Toinvestigatethedamagingeffectofhigh-intensityfocusedultrasound(HIFU)oncancercellsandtheinhibitoryeffectontumorgrowth.METHODS:MurineH22hepaticcancercellsweretreatedwithHIFUatthesameintensityfordifferentlengthsoftimeandatdifferentintensitiesforthesamelengthoftimeinvitro,thedeadcancercellsweredeterminedbytrypanbluestaining.TwogroupsofcancercellstreatedwithHIFUatthelowestandhighestintensitywereinoculatedintomice.Tumormasseswereremovedandweighedafter2wk,tumorgrowthineachgroupwasconfirmedpathologically.RESULTS:ThedeathrateofcancercellstreatedwithHIFUat1000W/cm2for0.5,1,2,4,8,and12swas3.11±1.21%,13.37±2.56%,38.84±3.68%,47.22±5.76%,87.55±7.32%,and94.33±8.11%,respectively.ApositiverelationshipbetweenthedeathratesofcancerceilsandthelengthofHIFUtreatmenttimewasfound(r=0.96,P＜0.01).ThedeathrateofcancercellstreatedwithHIFUattheintensityof100,200,400,600,800,and1000W/cm2for8swas26.31±3.26%,31.00±3.87%,41.97±5.86%,72.23±8.12%,94.90±8.67%,and99.30±9.18%,respectively.ApositiverelationshipbetweenthedeathratesofcancercellsandtheintensitiesofHIFUtreatmentwasconfirmed(r=0.98,P＜0.01).ThecancercellstreatedwithHIFUat1000W/cm2for8swereinoculatedintomiceexvivo.Thetumorinhibitoryratewas90.35%comparedtothecontrol(P＜0.01).IntheexperimentalgroupinoculatedwiththecancercellstreatedwithHIFUat1000W/cm2for0.5s,thetumorinhibitoryratewas22.9%(P＜0.01).Bypathologicalexamination,tumorgrowthwasconfirmedin8outof14mice(57.14%,8/14)inoculatedwiththecancercellstreatedwithHIFUat1000W/cm2for8s,whichwassignificantlylowerthanthatinthecontrol(100%,15/15,P＜0.05).CONCLUSION:HIFUiseffectiveonkillingordamageofH22hepaticcancercellsinvitroandoninhibitingtumorgrowthinmiceexvivo.