Recent work carried out on Sonic Hedgehog-driven medulloblastoma cells showed that pharmacological phenformin concentrations (1–5 μM) inhibit tumor growth independently of complex I and AMPK, through alterations in cytoplasmic redox potential and increased NADH levels [52], by inhibiting glycerol-3-phosphate dehydrogenase. This evidence concerns the gene PRKAA1 and medulloblastoma.