Interestingly, QPRT is exclusivelyexpressed in the World Health Organization high-grade (WHO grade III–IV)glioma and produces NAD+ using QA taken from normal microglial cells.This enables glioma to survive under conditions of oxidative stress andNAD+ depletion caused by therapeutic approaches, includingirradiation and alkylating agent treatment21. The gene discussed is QPRT; the disease is glioma.