Predisposing factors for patients with GBM include prior radiation in the area, ongoing dexamethasone treatment, and combination treatment with chemotherapy (cytotoxic alkylating agents, such as TMZ), or targeted treatments (e.g., bevacizumab, an antiangiogenic agent, or mammalian target of rapamycin [mTOR]/mitogen-activated protein kinase [MEK] inhibitors). This evidence concerns the gene MTOR and glioblastoma.