PRDM1 and neoplasm: We noticed that CD8+ cytotoxic T cell subpopulations were predominant in patient 1, who showed low expression of PRDM1 in tumor cells, whereas patient 2 showed a higher percentage of CD8+LAG3+ exhausted T cells and CD4+FOXP3+ Tregs, supporting the notion that PRDM1 overexpression potentiates T cell exhaustion (Fig. 8e).