The Gene Expression Profiling Interactive Analysis database (GEPIA2, http://gepia2.cancer-pku.cn) revealed a significantly higher expression of PD-L1 and IDO1 transcripts in GBM patient samples compared to normal tissue, and in both cases the difference in expression was marked when compared to low grade glioma (LGG) (Fig. 5A). Here, CD274 is linked to glioblastoma.