CD274 and central nervous system cancer: Overexpressed AP-2α in gliomas not only inhibits the transcription of PD-L1, but enhances the endocytosis and degradation of PD-L1 proteins in tumor cells and increases CD8+ T cell-mediated proliferation, effector cytokine secretion, and cytotoxicity in vitro, supporting a combination of demethylating drugs with anti-PD-1 immunotherapy to efficiently suppress the progression of gliomas [272].