In conclusion, in line with a previous study demonstrating that in vivo knockdown of PD-L1 in nude mice completely abolished GBM xenograft formation10, our finding shows that manipulation of PD-L1, through chemical inhibition of its co-chaperone FKBP51s, activates apoptosis and mitigates the aggressive features of GBM xenografts in nude mice. Here, CD274 is linked to glioblastoma.