To determine the applicability of PET imaging to GBM tumor in a more clinically relevant mouse orthotopic model, PET/CT imaging with 89Zr-DFO-LEM2/15 and a control 89Zr-DFO-IgG1 was performed 10 days after intracranial injections of patient-derived neurospheres (TS543). This evidence concerns the gene LEMD2 and glioblastoma.