The Hospital for Sick Children - Division of Haematology / Oncology, Charles University - Second Faculty of Medicine, Royal Children's Hospital, Saitama Children's Hospital, The Hospital for Sick Children - Division of Haematology / Oncology, Charles University - Second Faculty of Medicine, Charles University in Prague, Children’s Memorial Health Institute - Department of Pathology, Children’s Memorial Health Institute - Department of Pathology, The Chinese University of Hong Kong (CUHK) - Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong (CUHK) - Department of Anatomical and Cellular Pathology, Catholic University of Rome, Seoul National University, Seoul National University - University Children’s Hospital, Western University, Université de Lyon, Institut d'Hemato-Oncologie Pediatrique, Semmelweis University - 2nd Department of Pediatrics, McMaster University - Department of Pathology and Molecular Medicine, Erasmus Medical Center (MC), Erasmus Medical Center (MC), Emory University - Winship Cancer Institute, University of California, San Francisco (UCSF) - Department of Pediatrics, University of California, San Francisco (UCSF) - Department of Pediatrics, University of Pittsburgh, University of Pittsburgh - Department of Pathology, Mayo Clinic, Mayo Clinic, St. Louis Children's Hospital, Children's Health Queensland, Vanderbilt Medical Center, Children’s Hospital Colorado - Morgan Adams Foundation Pediatric Brain Tumor Research Program, University of Ulsan, Fondazione IRCCS Istituto Nazionale dei Tumori, Duke University, School of Medicine, Department of Pathology, The University of Sydney, - Department of Molecular Medicine & Medical Biotechnology, - Department of Molecular Medicine & Medical Biotechnology, Kitasato University, Hospital de Santa Maria, Masaryk University - University Hospital Brno, Pediatric Oncology Department, Chonnam National University, Hospital Pediatría Centro Médico Nacional Century XXI, Hospital Sant Joan 1 de Déu, University of São Paulo (USP) - Department of Surgery and Anatomy, Fred Hutchinson Cancer Research Center - Clinical Research Division, Seattle Children's Hospital, Royal Children's Hospital, Charles University in Prague, Charles University in Prague, The Hospital for Sick Children - Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children - Division of Haematology / Oncology, The Hospital for Sick Children - Division of Haematology / Oncology, The Hospital for Sick Children - Division of Haematology / Oncology, St. Jude Children’s Research Hospital - Department of Developmental Neurobiology, University of Toronto - Division of Neurosurgery, Monash University, The Hospital for Sick Children - Division of Haematology / Oncology and The Hospital for Sick Children - Division of Haematology / Oncology