Engineering Multifunctional Peptide-Decorated Nanofibers for Targeted Delivery of Temozolomide across the Blood–Brain Barrier

A nanoplatform based on self-assembling peptides was developed with the ability to effectively transport and deliver a wide range of moieties across the blood-brain barrier (BBB) for the treatment of glioblastoma. Its surface was functionalized to have a targeted release of TMZ thanks to the targeting peptide that binds to EGFRvIII, which is overexpressed on tumor cells, and gH625, which acts as an enhancer of penetration. Furthermore, the on-demand release of TMZ was achieved through matrix metalloproteinase-9 (MMP-9) cleavage. Nanofibers were characterized for their stability, critical aggregation concentration, and morphology. Next, the effect on both 2D and 3D glioblastoma/astrocytoma (U-87) and glioma (U-118) cell lines was evaluated. The Annexin V/Propidium iodide showed an increase in necrotic and apoptotic cells, and the morphological analysis allowed to discover that both U-118 and U-87 spheroids are smaller in surface, perimeter, and Feret's diameter when treated with NF-TMZ. The developed nanofiber was demonstrated to permeate the BBB <i>in vitro</i> in a 3D spheroidal biodynamic BBB model. Finally, there were no cytotoxic effects of nanofibers without the drug on spheroids, while a significant decrease in viability was observed when NF-TMZ was used. Overall, these results open new opportunities for the evaluation of the efficacy and safety of this nanoplatform in <i>in vivo</i> studies.