library_construction_protocol: Tumor cells were isolated from the cerebellum of adulthood using percoll gradient centrifugation. Nuclei isolation was performed according to the manufacturer's protocol (CG000366 Rev C, 10x Genomics). Of note, the incubation with the lysis buffer was optimized to 3 minutes. Targeted Nuclei Recovery was 5000 or 10000, depending on the number of isolated nuclei. Library preparation was performed according to the manufacturer's protocol (CG000338 RevE, 10x Genomics).