CD274 and meningioma: The aims of this study were to detect the expression of PD‐L1 in NF2‐associated meningiomas, explore the effect of PD‐L1 downregulation on tumor cell characteristics and T‐cell functions, and investigate the possible pathways that regulate PD‐L1 expression to further dissect the possible mechanism of immune suppression in NF2 tumors and to provide new treatment options for NF2 patients.