High-grade gliomas showed the highest HLA class I expression, with median HLA-A between 8.8 and 9.5 and HLA-C between 7.7 and 8.4 across H3G34-DHG, H3K27M-DMG, H3WT-HGG, and adult HGG, consistent with stronger antigen presentation. The gene discussed is HLA-A; the disease is central nervous system cancer.