All psoriasis lesions also had detectable levels of activated Stat3, a protein indicated in development of the disease, whereas control tissue lacked this protein.
We identified seven susceptibility loci outside the human leukocyte antigen region (9p24 near JAK2, 10q22 at ZMIZ1, 11q13 near PRDX5, 16p13 near SOCS1, 17q21 at STAT3, 19p13 near FUT2, and 22q11 at YDJC) shared between PS and CD with genome-wide significance (p < 5 × 10(-8)) and confirmed four already established PS and CD risk loci (IL23R, IL12B, REL, and TYK2).
It has been demonstrated that epidermal Stat3 activation is required for psoriasis development, since keratinocyte-specific Stat3 activation in a mouse model elicits a psoriasis-like phenotype, which is reversed by inhibition of Stat3 signaling.
We further show that overexpression of hsa-miR-4516 downregulates STAT3, p-STAT3, CDK6, and UBE2N proteins that are consistently upregulated in psoriasis and induces apoptosis in HaCaT cells.
Several mouse models of psoriasis including drug-induced models (topical application of imiquimod to the skin) and genetically engineered mice (constitutive activation of epidermal STAT3, epidermal deletion of JunB/c-Jun, and epidermal overexpression of Tie2) have been used to study the pathophysiology of the disease; however such models cannot fully recapitulate all molecular and cellular pathways occurring in human psoriasis.
We also found that IL-22 increases CD147 transcription in vitro and in vivo and that Stat3 binds directly to the CD147 promoter between positions -854 and -440, suggesting that CD147 expression is up-regulated in patients with psoriasis through Stat3 activation.
rs744166GG in STAT3 and rs7574865TT in STAT4 had higher frequencies in the case than the control group, suggesting these 2 genotypes increase the susceptibility to psoriasis (p < 0.05).
Silencing the target gene STAT3 in psoriatic KCs with siRNA combined with ultrasonic irradiation and microbubbles would contribute to a significant innovation as a new clinical therapy for psoriasis.
It was observed that 'psoriasis 1' downregulated the concentrations of TNF‑α, IFN‑γ, IL‑22, IL‑17C, IL‑1β and IL‑4, and upregulated the concentration of 25HVD3; furthermore, 'psoriasis 1' downregulated the expression levels of NF‑κB, phosphorylated (p)‑NF‑κB, IKK, p‑IKK, STAT3, p‑STAT3, STAT4 and p‑STAT4, and upregulated the expression level of VDR in TNF‑α‑induced HaCaT cells.
Taken together, our findings indicated that the curative effects of CTS on psoriasis are accomplished mainly through modulating STAT3, which providing evidences to develop CTS as a potential therapeutic agent for patients with psoriasis.
STAT3 was overexpressed in the intestinal mucosa of active and non-active IBD, and a similar upregulation was seen in skin biopsies from EN [84.7 vs 22.3, p < 0.001] and PG [60.5 vs 22.3, p = 0.011], but not in psoriasis.
Using a preclinical model of psoriasis, we show that intradermal injection of APTstat3 tagged with a 9-arginine cell-penetrating peptide (APTstat3-9R) reduced disease progression and modulated psoriasis-related cytokine signaling through inhibition of STAT3 phosphorylation.
Our findings indicate that miR-320b negatively regulates NHEK proliferation by targeting AKT3 to regulate the STAT3 and SAPK/JNK signaling pathways and might participate in the pathogenesis of psoriasis in Chinese Han populations. miR-320b may also be a novel diagnostic marker or therapeutic target for this disease.
Together, our results reveal a novel regulatory mechanism of IL-22 expression by STAT1 through directly antagonizing STAT3, and the importance of the balance between STAT3 and STAT1 in IL-22 regulation and psoriasis pathogenesis.