Although only a slight increase in PD-L1 expression was observed in SVZ-GBM cells growing in spheres (Fig. 3f), the finding that PD-L1 silencing impaired the capacity to form spheroids in both TM- and SVZ-GBM cells (Fig. 3g) highlighted the importance of PD-L1 in spheroid formation. This evidence concerns the gene CD274 and glioblastoma.