Indeed, 5-Aza-dC treatment has previously shown to induce PD-L1 demethylation and consequential mRNA and/or protein re-expression in the KG1 leukemia cell line, in vitro activated primary CD8+ T cells, CD4+ and CD8+ T cells from patients with myelodysplastic syndrome and acute myeloid leukemia [32–34]. Here, CD4 is linked to leukemia.