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). Here, HHEX is linked to acquired polycythemia vera.