Nanomedicine for Glioblastoma: Cutting-Edge Advances and Persistent Challenges

Cancer is a disorder characterized by the abnormal growth of cells that increases uncontrollably over an extended period of time. Treating cancerous brain tumors remains among the most challenging tasks for researchers, as brain tumors are among the hardest cancers to treat. Additionally, the condition often worsens because of the delayed diagnosis caused by the absence of early symptoms. The use of conventional treatment methods, such as radiation, chemotherapy, and surgery, continues to be highly limited. The low solubility, narrow therapeutic index, and limited ability to traverse the blood–brain barrier of most anticancer drugs result in limited therapeutic efficacy. In an attempt to overcome these predicaments, formulation scientists have been considering nanotechnology-based therapeutic solutions, particularly given the increasing rates of brain cancers that have low survivability and the drawbacks of the existing treatment methods. Different nanoplatforms, such as polymeric nanoparticles, nanoliposomes, dendrimers, carbon nanotubes, and magnetic nanoparticles, have been explored. Research has indicated that such nanocarriers can increase the delivery of drugs to cells in brain tumors with a minimal off-target distribution, resulting in minimal adverse effects and optimal treatment. This review presents a summary of nanocarrier-based drug delivery systems that have been reported in recent years for the treatment of brain tumors. In addition, it explains the existing difficulties with the clinical implementation of nanodrug carriers and the perspectives of this field.