The expression of REL, an important regulator of the anti-inflammatory factors IL-12 and IL-10 signaling, and RUNX3, a regulator that inhibits myeloid cell differentiation, as well as several unknown regulators (NR2C1, BHLHE40, ZNF250, HES6, and FOXP4) were downregulated in NK cells from PV patients compared with HCs; we also found upregulation of the expression of NFIL3, an important TF for NK cell differentiation, and other regulators (NUAK1, HIVEP1, HHEX). This evidence concerns the gene RUNX3 and acquired polycythemia vera.