In GBM, CD274 expression was positively correlated to HAVCR2, PDCD1LG2, and SIGLEC15, while that of CTLA4 correlated positively with HAVCR2, LAG3, TIGIT, PDCD1, PDCD1LG2, and SIGLEC15. Here, PDCD1 is linked to glioblastoma.