CD8A and neoplasm: To further investigate the expression of these three signature genes in the tumor microenvironment at the single-cell level, we first identified nine major cell clusters using the Seurat R package: AC-like malignant cells, CD8-exhausted T cells, M1 macrophages, malignant cells, MES-like malignant cells, monocytes, NPC-like malignant cells, oligodendrocytes, and OPC-like malignant cells (Figure 6A).