Therapeutic efficacies of combination HIFU with paclitaxel thermosensitive liposomes on Lewis lung carcinoma in mice

Objective To investigate therapeutic efficacies of combination high intensity focused ultrasound(HIFU)with paclitaxel thermosensitive liposomes on Lewis lung carcinoma(LLC)in mice.Methods Lewis carcinoma models were established in 60 Kunmin mice.Mice were stratified by volume and randomly assigned to one of the six groups:control(Con),HIFU along(HIFU),free paclitaxel along(PTX),free paclitaxel with HIFU(PTX+HIFU),paclitaxel themosensitive liposomes(PTL),paclitaxel themosensitive liposomes with HIFU(PTL+HIFU).Saline,free paclitaxel,paclitaxel themosensitive liposomes were injected i.v.in mice followed by 30 min HIFU exposure with the temperature maintained at 42-43 ℃ in tumor,and treatments were repeated at day 4,7.Mice were monitored,and tumors were measured every day posttreatment.Mice were scarificed at day 10 and pathologic examination was performed.Results All mice well tolerated the treatment.The tumor inhibition rate in PTL+HIFU group was 71.6%,which was significantly higher than that of PTX+HIFU group(50.0%,P0.05).The tumor inhibition rate in PTL group and PTX group were 23.4% and 21.3%,respectively.There was no significant differences between PTL and PTX groups(P0.05).Pathologic study showed obvious tumor cells necrosis in PTL+HIFU group,and mild tumor cells necrosis in PTL and PTX groups.However,there was no tumor cells necrosis observed in Con and HIFU groups.Conclusions HIFU combined with paclitaxel themosensitive liposomes enhance antitumor effects on LLC.These results imply that HIFU can be used as a target heating device for tumor targeting therapy using thermosensitive liposomes.