Brain tumor
Glioblastoma multiforme (GBM) is the most aggressive (grade IV) and most common form of a malignant brain tumor. Even when aggressive multimodality therapy consisting of radiotherapy, chemotherapy, and surgical excision is used, median survival is only 12–17 months. Standard therapy for glioblastoma multiforme consists of maximal surgical resection of the tumor, followed by radiotherapy between two and four weeks after the surgical procedure to remove the cancer, then by chemotherapy, such as temozolomide. Most patients with glioblastoma take a corticosteroid, typically dexamethasone, during their illness to relieve symptoms. Experimental treatments include targeted therapy, gamma knife radiosurgery, boron neutron capture therapy and gene therapy.
Spherical nucleic acid
SNAs packed gold nanoparticles are able to deliver small interfering RNA (siRNA) to treat glioblastoma multiforme in a proof-of-concept study using mouse model, reported by the research team led by Mirkin. The iRNA targets Bcl2Like12 gene overexpressed in glioblastoma tumors and silences the oncogene. The gold nanoparticles injected intravenously cross the blood-brain barrier and find their target in the brain. In the animal model, the treatment caused a 20% increase in survival rate and 3 to 4 fold reduction in tumor size. Mirkin indicated that this novel therapeutic approach establishes a platform for treating a wide range of diseases.