HK2 and medulloblastoma: As shown in Fig. 2a, b, the medulloblastomas are marked by a robust accumulation of many key glycolytic enzymes, including hexokinase II (HKII), pyruvate kinase M2 (PKM2), and glucose transporter type 4 (Glut4), which control glucose transport, especially into muscle and adipocytes in response to insulin stimulation.