Exploring Therapeutic Advancement and Strategies Associated with Drug Delivery in Brain-Tumor Targeting.

Brain tumors pose a serious burden to health care because the cancers are usually incurable, despite advancements in treatment strategies including surgery, radiotherapy, and chemotherapy. Most studies report that specific drugs are effective in vitro, but many lose their therapeutic value in clinical settings. Maintaining therapeutic drug concentrations as an agent reaches a cancer target is the efficacy prerequisite for any form of treatment. However, in the case of brain tumors, the blood-brain barrier (BBB) acts to physically and physiologically block the drug, which complicates treatment options. In addition, strategies are limited by a number of factors such as difficulties that are associated with targeting tumor cells. The therapeutic potential of targeted drug delivery as an alternative to current strategies is gaining significant ground, with many studies highlighting its efficacy and compatibility in overcoming the BBB before reaching its final target in brain. In this review, we briefly describe basic physiology associated with the BBB and how modern science is taking advantage of physiological processes to deliver anticancer agents to brain. We also summarize different modes of drug delivery and highlight how nanoparticles as drug-delivery vehicles are used for drug transport in brain tumors as well as different types of surface modification that are used to increase target potential.