Glioblastoma multiforme (GBM) is a malignant tumor that arises from the glial cells, the brain’s support tissue. GBM tumors are grade IV tumors, which means they are aggressive and can spread to healthy brain tissue. Certain genetic diseases including neurofibromatosis type 1 (NF1), Li-Fraumeni syndrome and tuberous sclerosis are sometimes the reason why GBMs occur.