Figure 5.

In vivo efficacy of TMZ-based therapeutic thermogels using a GBM resection and recurrence mouse model. (a) Experimental timeline for studying the in vivo anticancer activities of gel-based local glioblastoma treatments. Two independent experiments comparing empty THG with THG@SIO₂-TMZ and THG@PCL-TMZ, respectively, were performed (n = 5). Results were next merged resulting in n = 8 for THG, n = 3 for THG@SIO₂-TMZ and n = 4 for THG@PCL-TMZ, considering drop-outs due to the severity of the procedure. (b) Representative BLI images of mice bearing U87-MG-Red-FLuc implantation in the subcortical striatal region. After primary tumor resection, THG@SIO₂-TMZ, THG@PCL-TMZ or empty THG were applied. (c) Tumor growth was directly related to the increment of luminescence signal normalized to baseline (day 2 after resection, corresponding to Time 0 in panels A and B) and recorded at days 7 (Time 1), 14 (Time 2) and 21 (Time 3) after resection, in THG, THG@SiO₂-TMZ and THG@PCL-TMZ groups. Tumor growth was expressed as fold increase [Lum(tx)−Lum (t0)/Lum (t0)]. THG@SIO₂-TMZ or THG@PCL-TMZ reduced tumor recurrences when compared to empty THG treatment (*p < 0.05; two-ways ANOVA p < 0.05). (d). Luminescence signals from control (empty THG) animals on day 21 are significantly higher (*p < 0.05; Kruskal–Wallis test p < 0.004). (e) Site of the resection in relation to the Paxinos representation of brain coronal section at the injection coordinate (− 0.5 mm). Representative images of H&E-stained brain sections collected 21 days after tumor resection and gel application from mice receiving either THG@SIO₂-TMZ, THG@PCL-TMZ or empty THG (control animals) show the growth of the tumor mass to the areas adjacent to the cancer cells injection site.