Human glioblastoma-derived cell membrane nanovesicles: a novel, cell-specific strategy for boron neutron capture therapy of brain tumors

Glioblastoma (GBM), one of the deadliest brain tumors, accounts for approximately 50% of all primary malignant CNS tumors, therefore novel, highly effective remedies are urgently needed. Boron neutron capture therapy, which has recently repositioned as a promising strategy to treat high-grade gliomas, requires a conspicuous accumulation of boron atoms in the cancer cells. With the aim of selectively deliver sodium borocaptate (BSH, a 12 B atoms-including molecule already employed in the clinics) to GBM cells, we developed novel cell membrane-derived vesicles (CMVs), overcoming the limits of natural extracellular vesicles as drug carriers, while maintaining their inherent homing abilities that make them preferable to fully synthetic nanocarriers. Purified cell membrane fragments, isolated from patient-derived GBM stem-like cell cultures, were used to prepare nanosized CMVs, which retained some membrane proteins specific of the GBM parent cells and were devoid of potentially detrimental genetic material. In vitro tests evidenced the targeting ability of this novel nanosystem and ruled out any cytotoxicity. The CMVs were successfully loaded with BSH, by following two different procedures, i.e. sonication and electroporation, demonstrating their potential applicability in GBM therapy.