CD274 and central nervous system cancer: In our study, expression frequency of PD-L1 was 51.1% and a significant association was confirmed between PD-L1 expression and worse prognosis in the patients with gliomas during long-time survival or follow up, and stratified analysis revealed that PD-L1 expression was significantly associated with adverse OS and DFS for patients with gliomas of grade IV in these patients, suggesting that the immunotherapy of PD-1 and PD-L1 could be effective in the patients with gliomas, especially in the patients with grade IV to further improve the poor survival time.