CD274 and Anaplastic (Malignant) Meningioma: Others have identified that the presence of immunosuppressive myeloid cells in high-grade meningioma11,12, linked PD-L1/PD-L2 expression with worse outcomes10,12, and found enrichment of PD-1/PD-L1 signaling in malignant meningiomas by single-cell RNA sequencing11.