CD274 and glioblastoma: In fact, it was recently reported that ionizing radiation enhances the expression of immune-suppressive markers on GBM cells and induce in some tumor microenvironment (TME) cells, such as macrophages, the upregulation of programmed death-ligand 1 (PD-L1) in response to extracellular vesicles (EVs) released by GBM cells, and the increase of CD206+ macrophages with pro-oncogenic properties [18].