In vivodistribution and tumor accumulation assays In order for in vivo distribution and tumor accumulation assays, lymphoma-bearing SCID mice were injected with free ADR and ADR-loaded liposomes (PC-ADR-BSA and PC-ADR-Fab) via tail vein. Twenty-four hours after treatment, tissues were harvested and the sum total ADR was extracted and measured. Figure 6A shows that there was a significant
increase in tumor ADR accumulation in PC-ADR-Fab compared with PC-ADR-BSA (*p = 0.048) and free ADR-treated mice (**p = 0.000). The heart, liver, spleen, and lungs all showed less ADR accumulation with liposomal ADR treatment than with TPX-0005 free ADR treatment. There was no difference in ADR accumulation among treatments for the kidneys. The displayed fluorescent image of different frozen sections (Figure 6B) also demonstrated distinct enhancement of red fluorescence in tumor tissues of mice treated with ADR-loaded liposomes compared with that treated with free ADR, and the administration of PC-ADR-Fab LBH589 can induce more retention of ADR in tumor tissues than the administration
of PC-ADR-BSA for the active targeting of Fab fragments. Figure 6 In vivo antitumor activity of ADR-loaded liposomes. (A) Lymphoma-bearing SCID mice were treated with 5 mg/kg free ADR, PC-ADR-Fab, and PC-ADR-Fab; 24 h later, mice were euthanized and organs were harvested, washed, and weighed; and the ADR was extracted and quantified. (B) In vivo tumor accumulation profile of frozen section from lymphoma-bearing SCID mice treated with free ADR, PC-ADR-BSA, and PC-ADR-Fab for 24 h as visualized by confocal microscopy, the RED fluorescence represents the tumor accumulation and retention of ADR. Scale bar 50 μm. (C) In vivo anticancer therapeutic effects in localized human NHL xeno-transplant MK-2206 manufacturer models after the first intravenous administration of PBS, free ADR, PC-ADR-BSA, and PC-ADR-Fab. Tumor volumes were measured every 3 days. Results are presented as mean ± SD of four separate mice in one group. →, treatment.
(D) In vivo antitumor therapeutic effects in disseminated human NHL xeno-transplant models after the first intravenous administration of PBS, free ADR, PC-ADR-BSA, and PC-ADR-Fab. Survival curves were plotted with the Kaplan-Meier method and were compared by using a log-rank PAK5 test. In vivoantitumor activity assessment For the evaluation of in vivo antitumor activities, both the disseminated and localized human NHL xeno-transplant models were set up. In the localized model, Daudi cells were inoculated subcutaneously in the right flank of SCID mice. When the tumors reached about 50-60 mm3 in volume, mice were randomly treated with free ADR, PC-ADR-BSA and PC-ADR-Fab with an equivalent ADR amount of 5 mg/kg [25, 38]. The mice were treated once a week for SCID mice based on previous study and our preliminary experimental results [39]. The tumor volume was recorded and illustrated in Figure 6C.