The nanocarrier strategy for crossing the blood-brain barrier in glioma therapy

Glioma is the most common malignant tumor of the brain. The postoperative recurrence rate was high, and the 2-year survival rate only increased by 20%–25%. The reason is the blood-brain barrier (BBB). BBB is a physical barrier that stabilizes the physiological environment of brain tissue and protects the central nervous system from the invasion of harmful substances. Drug delivery based on nanotechnology and nanocarriers has attracted much attention due to its biological safety, continuous drug release time, increasing solubility, biological drug activity, and enhanced BBB permeability. By modifying different substances on the surface of nanocarriers, the BBB is bypassed by receptor-mediated and cell endocytosis and exocytosis. In addition, the purpose of bypassing BBB-targeted drug delivery can also be achieved by intranasal administration and local administration. This paper reviews different target transport mechanisms, mainly in invasive and non-invasive strategies, the nanocarriers that have made progress and the nanocarrier strategy of bypassing BBB are listed.