Fig. 6.

Survival distributions of tumor-bearing mice were significantly prolonged by nanoformulated CCL21 treatment. A/J mice bearing subcutaneous Neuro2a neuroblastoma tumors received intratumoral injections with one of the following agents: nanoformulated CCL21 (n=21), CCL21 alone (n=20), empty nanoparticles (n=12), or buffer control (n=12). The Neuro2a tumor-bearing mice were given 1 dose in the morning and 1 dose in the evening on 2 consecutive days of 6 μg of CCL21/25 μL, or 6 μg of CCL21 in nanoformulation/25 μL per dose, or an equal amount of empty nanoparticles/25 μL, or 25 μL of buffer alone (Fig. S1). After receiving the treatments, the mice were monitored at least 3 times weekly until their tumor burdens reached 1000 mm³ or 54 days had elapsed since treatment initiation (day 0). Nanoformulated CCL21-treated mice survived significantly longer than mice treated with buffer control (p = 0.008), empty nanoparticles (p = 0.002), or CCL21 alone (p = 0.003). Kaplan-Meier and log-rank analyses were used to compare survival distributions of mice between treatment groups. Survival distributions were generated using Kaplan-Meier Survival Methods and portray cumulative survival in time (days), where day 0 indicates treatment initiation, not the implantation of tumor cells. Mean survival time post-treatment initiation ± standard deviation was determined for each treatment group. These data are a cumulative representation of 3 independent experiments.