The novel and potential future IBD drug Apremilast (a phosphodiesterase-4 (PDE4) inhibitor) has been shown to target a macrophage phenotype switch (M1 to M2) by down-regulating inflammatory responses through the inhibition of NF-κB transcriptional activity and NF-κB -dependent genes [23,24,25], and has already been successfully tested in a phase II trial in patients with active ulcerative colitis (UC) [26]. Here, NFKB1 is linked to ulcerative colitis.