Glycolytic phenotype is common to CGNPs and medulloblastoma in vivo. (A) Cerebellar glucose flux was higher at P5, during CGNP proliferation, than at P20 after neurogenesis was completed, as measured by 18FDG uptake 1 hour after IP injection (P < 0.02). Experiment repeated 3 times using paired littermates at P5 and P20 and data presented as mean ± SEM. Uptake by forebrain was also measured and used to normalize for dose to the brain. (B)1H MRS consistently demonstrated a lactate doublet in cerebella of P12 pups (n = 3), in voxel defined by the box shown in the inset. This doublet was not observed in adult cerebella, or forebrain in P12 animals (data not shown). (C) Medulloblastoma (red arrowhead) in ND2:SmoA1 mice demonstrated markedly elevated 18FDG uptake on PET/CT, compared with age-matched control (below). PET/CT in 3/3 tumor-bearing mice demonstrated increased glucose uptake and a representative scan is shown.