CREB1 and psoriasis: Aberrant PLD/PtdOH signaling activates phosphodiesterase (PDE) 4 family members in a Camp-dependent manner (38), which further activates cascade of several signaling steps (e.g., PKA/CREB/NFκb), leading to increased proinflammatory cytokines TNF-α, IL-23, IFN-β and γ and promote psoriasis progression (39, 40).