TNF and psoriasis: One of the key inflammatory cytokines observed to be in elevated levels in psoriasis is tumor necrosis factor α (TNF-α) which binds to its specific receptors, TNFR1 and TNFR2, and stimulates the nuclear factor kappa B (NF-κB) signaling pathway to initiate rapid transcription of other inflammatory genes such as IL-6, IL-8, IL-1β and INF-γ, as depicted in Fig. 1 [3, 13–16].