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.
Glioblastoma
Cancer cells with properties similar to stem cells have been found in glioblastomas (this may be a cause of their resistance to conventional treatments, and high recurrence rate). These so-called glioblastoma stem-like cells reside in a niche around arterioles, protecting these cells against therapy by maintaining a relatively hypoxic environment. A biomarker for cells in glioblastomas that exhibit cancer stem cell properties, the transcription factor Hes3, has been shown to regulate their number when placed in culture.