Gliomas are a major cause of cancer-related deaths in younger adults. About 7,000 patients harbor a common genetic mutation that affects the enzyme isocitrate dehydrogenase 1. This mutated enzyme, called mIDH1, can produce a molecule that can reprogram both the tumor cells and the environment in which they grow. The molecule, known as 2-hydroxyglutarate, can also circulate in the blood and reprogram immune cells in the bone marrow.