Gene Therapy Based on Lipid Nanoparticles as Non-viral Vectors for Glioma Treatment.

Gliomas are primary brain tumors originating from glial cells, representing 30% of all Central Nervous System (CNS) neoplasia. Among them, the astrocytoma grade IV (glioblastoma multiforme) is the most common, presenting an invasive and aggressive profile, with an estimated life expectancy of about 15 months after diagnosis even after treatment with radiation, surgical resection, and chemotherapy. This poor prognosis is related to the presence of the blood-brain barrier (BBB) and multidrug resistance mechanisms that prevent the uptake and retention of chemotherapeutics inside the brain. Gene therapy has been a promising strategy to overcome these treatment limitations since it has the ability to modify the defective genetic information in tumor cells, being able to induce cellular apoptosis and silence the genes responsible for multidrug resistance. Lipidbased nanoparticles, non-viral vectors, have been investigated to deliver genes across the BBB to reach the glioma cell target. Besides, their low immunogenicity, easy production, ability to incorporate ligands to specific target cells, and capacity to carry higher size genes have made the gene therapy based on non-viral vectors a promising glioma treatment. In this context, this review addresses the most common non-viral vectors based on lipid-based nanoparticles used for glioma gene therapy, such as liposomes, solid lipid nanoparticles, nanostructured lipid carriers, and nanoemulsions.