Compared with other tumor and normal cells, the ecDNA+ cell cluster also overexpressed GLI2 (q < 0.001), a mediator of SHH-mediated transcription and marker for SHH medulloblastoma, despite GLI2 not being affected by copy number alteration in this tumor (Fig. 3g and Supplementary Table 19). Here, SHH is linked to medulloblastoma.