Glioblastoma multiforme (GBM) is one of the most challenging diseases to treat in clinical oncology
due to its high mortality rates and inefficient conventional treatment methods. Difficulties with early detection,
post-surgical recurrences, and resistance to chemotherapy and/or radiotherapy are important reasons for the poor
prognosis of those with GBM. Over the past few decades, magnetic resonance (MR) theranostics using magnetic
nanoparticles has shown unique advantages and great promises for the diagnosis and treatment of cancers. Magnetic
nanoparticles not only serve as "molecular beacons" to enhance tumor contrast in magnetic resonance imaging
(MRI), but also serve as "molecular bullets" for targeted drug delivery, controlled release, and induced hyperthermia.
Moreover, multiple functions of magnetic nanoparticles can be synergistically engineered into a single
nanoplatform, making it possible to simultaneously image, treat, target, and monitor the targeted lesions. The
multi-functionality of nanoparticles, also called nano-theranostics, gives rises to effective new approaches for combating GBM. In this
work, recent research and progress concerning the applications of MR nano-theranostics on GBM using magnetic nanoparticles will be
highlighted, focusing on topics such as diagnosis, therapy, targeting, and hyperthermia, as well as outstanding challenges for MR nanotheranostics
in treating GBM. The conclusions are generally applicable to other types of brain tumors.