A pool of five tumor-associated antigens (B7-H3, GD2, ILR13α2, HER2, and EPHA2) has, nevertheless, been identified in PBTs, mostly as a result of research on adult GBM [38,40,41,42] These antigens have recently been ranked according to their abundance across a panel of 49 patient-derived orthotopic xenograft (PDOX) samples, including medulloblastomas, ATRTs, ependymomas, and high-grade gliomas (HGGs). The gene discussed is EPHA2; the disease is ependymoma.