Study of Stored Tumor Samples in Young Patients With Brain Tumors

The overall objective of this non-therapeutic protocol is to develop and molecularly characterize patient-derived orthotopic xenografts (PDOXs), organoids and in vitro models derived from medulloblastomas, High Grade Neuroepithelial Tumors (HGNET), CNS embryonal tumors, Atypical Teratoid Rhabdoid Tumors (ATRTs), Choroid Plexus Carcinomas (CPCs), ependymomas, and gliomas. The investigators will characterize the genome-wide mutation, expression and epigenetic signatures of these models and compare them with the primary tumors from which they were derived, thus creating a well-characterized and invaluable resource for research on these rare and deadly pediatric brain tumors. This will also provide important insights into intratumoral heterogeneity, and molecular abnormalities that may influence the selective pressures driving evolution, and tumor growth as in PDOXs, organoids or in vitro cultures and define the relationship between these abnormalities and tumor histologic and clinical characteristics. This objective will be achieved by applying state-of-the-art DNA, RNA and epigenome analysis tools to the study of fresh frozen and/or cryopreserved, fixed and cultured tumor cells, PDOXs and organoids. The establishment of patient-derived orthotopic xenografts, organoids and cell cultures from each tumor sample will also allow for in vitro and in vivo analysis of tumor cell growth, signaling and therapeutic response.