NFKB1 and acute promyelocytic leukemia: Wu et al. showed that translocation of MARRS and NFκB to the nucleus, upon co-stimulation with calcitriol and phorbol ester, preceded the expression of the monocyte/macrophage phenotype of NB4 promyelocytic leukemia and suggested a role for MARRS as a regulator of gene expression in the nucleus [27].