Theranostics Micelles for Brain Tumor Diagnosis and Treatment

Brain cancer is considered one of the most vicious and devastating tumors owing to its poor prognosis and high mortality rate. Common strategies for treatment include surgery, radiation, and chemotherapy. Unfortunately, these are limited due to their invasive nature and the inherent difficulties of brain surgery, given there is a high possibility of tumor relapse. Further, radiation and chemotherapy have a non-selective harmful effect on normal tissues, accompanied by limited drug delivery due to the presence of various barriers, including the blood-brain barrier. For this reason, the theranostic approach was developed by incorporating one or more therapeutic and diagnostic agents in a single nanocarrier moiety which could be modulated at its surface with certain proteins, legend, surface markers, or a stimuli-responsive agent that is capable of selectively targeting the tumor site after passing through the blood-brain barrier. This new field will permit the early and precise detection of cancer tissue, facilitate the process of drug delivery and assist in monitoring treatment outcomes. Micelles are considered one of the most commonly used nanocarriers due to their high stability and loading capacity, along with efficient release controlling properties. This chapter will present brief information about brain anatomy and cancer, and will discuss the main strategies implemented in the diagnosis and treatment of brain cancers. Furthermore, it will introduce the theranostic micelle approach by highlighting micelles types and preparation techniques, as well as explain the different barriers and approaches to targeting.

Keywords: Active targeting, Blood-brain barrier, Blood-brain tumor barrier, Brain cancer, Brain tumor stem cells, Chemotherapy, Computed tomography, Focused ultrasound, Gene therapy, Magnetic resonance imaging, Optical imaging, Paracellular, Passive targeting, Photodynamic therapy, Photothermal therapy, Polymeric micelles, Stimuli-responsive targeting, Theranostic, Transcellular, Tumor microenvironment.