Biodegradable SPI-based hydrogel for controlled release of nanomedicines: a potential approach against brain tumors recurrence

Glioblastoma (GB) is the most common and aggressive brain tumor. The treatment for newly diagnosed glioblastoma is surgical resection of the primary tumor mass, followed by radiotherapy and chemotherapy. However, recurrences frequently occur in proximity to the surgical resection area. In these cases, none of the current therapies is effective. Recently, implantable biomaterials seem to be a promising strategy against GB recurrence. Here, for the first time we combined the tailorable properties of soy-protein hydrogels with the versatility of drug-loaded liposomes to realize a hybrid biomaterial for controlled and sustained nanoparticles release. Hydrogel consisting of 18–20 % w/v soy-protein isolated were fabricated in absence of chemical cross-linkers. They were biodegradable (−10 % and −30 % of weight by hydrolytic and enzymatic degradation, respectively in 3 days), biocompatible (>95 % of cell viability after treatment), and capable of sustained release of intact doxorubicin-loaded liposomes (diffusion coefficient between 10−18 and 10 −19 m2 s−1). A proof-of-concept in a “donut-like” 3D-bioprinted model shows that liposomes released by hydrogels were able to diffuse in a model with a complex extracellular matrix-like network and a 3D structural organization, targeting glioblastoma cells. The combination of nanoparticles' encapsulation capabilities with the hydrogels' structural support and controlled release properties will provide a powerful tool with high clinical relevance that could be applicable for the treatment of other cancers, realizing patient-specific interventions.