TNFRSF9 and neoplasm: Evaluating the DEGs within the tumor CD8 GPR56-positive vs. the GPR56-negative T cell fractions, again revealed cytotoxic/(pre-)exhausted/tumor-reactive signatures, reflected by the upregulation of genes, such as ENTPD1 (CD39), ITGAE (CD103), CXCL13, TNFRSF9 (4-1BB), HAVCR2, CTLA4, and CX3CR1 (Figure 2D, highlighted in orange).