Abstract: Gliomas are the most common tumor of the central nervous system. However, the presence of the brain barrier blocks the effective delivery of drugs and leads to the treatment failure of various drugs. The development of a nanoparticle drug delivery system (NDDS) can solve this problem. In this review, we summarized the brain barrier (including blood–brain barrier (BBB), blood–brain tumor barriers (BBTB), brain–cerebrospinal fluid barrier (BCB), and nose-to-brain barrier), NDDS of glioma (such as passive targeting systems, active targeting systems, and environmental responsive targeting systems), and NDDS efficacy improvement strategies and deficiencies. The research prospect of drug-targeted delivery systems for glioma is also discussed.

Malignant tumors are life-threatening, and chemotherapy is one of the common treatment methods. However, there are often many factors that contribute to the failure of chemotherapy. The multidrug resistance of cancer cells during chemotherapy has been reported, since tumor cells’ sensitivity decreases over time. To overcome these problems, extensive studies have been conducted to reverse drug resistance in tumor cells. Elemene, an extract of the natural drug Curcuma wenyujin, has been found to reverse drug resistance and sensitize cancer cells to chemotherapy. Mechanisms by which elemene reverses tumor resistance include inhibiting the efflux of ATP binding cassette subfamily B member 1(ABCB1) transporter, reducing the transmission of exosomes, inducing apoptosis and autophagy, regulating the expression of key genes and proteins in various signaling pathways, blocking the cell cycle, inhibiting stemness, epithelial–mesenchymal transition, and so on. In this paper, the mechanisms of elemene’s reversal of drug resistance are comprehensively reviewed.