The Expressions Of MicrorRNA-155 And SOCS 1 In Skin Of Psoriatic Patients And Their Action Mechanism

【Objective】To investigate the expressions of miR-155 and SOCS1 genes in the lesional skin and adjacent non-lesional skin of psoriatic patients and the role of miR155-SOCS1 axis in psoriasis.【Methods】Biopsies were carried out on 12 psoriatic patient donors to obtain lesional skin and adjacent nonlesinal skin which were made into FFPE samples. Real-time PCR were carried out to compare the abundance of miR-155 and mRNA expression levels of STAT3 and SOCS1 genes between lesional and nonlesinal psoriatic skin. In situ hybridization was performed localize the expression of miR-155. The expressions of protein SOCS1 and phosphorylated STAT3 were observed by immunohistochemistry. Imiquimod-induced murine psoriasiform dermatitis model was established and given intradermal injection of microRNA antagomir and agomir. The expression levels of gene SOCS1, STAT3 and several associated cytokines in lesional and non-lesional skin were examined by RT-PCR and/or Western Blot.【Results】The expressions of miR-155 and mRNA expression of STAT3 and SOCS1 genes in lesional skin were significantly higher than nonlesional skin (P=0.0005, P=0.0002, P=0.0081, respectively). In situ hybridization showed miR-155 expression in both epidermis and dermis, higher in basal cell layer and mainly localized in nucleus. Immunohistochemistry showed phosphorylated STAT3 and SOCS1 located mainly in mucleus and the expression was stronger in psoriatic skin than in non-psoriatic skin (P<0.05). Antagomir-155 elevated the protein expression level of SOCS1 while the mRNA expression level showed no significant change, decreased the mRNA expression level and protein expression level of STAT3. The mRNA expression levels of TNF-α, IL-23 and IL-6 were also decreased. The mRNA expression of IL-17 showed decreasing tendency. Agomir-155 led to no significant changes in the expression levels of STAT3, SOCS1 and associated cytokines.【Conclusion】The expression of miR-155 and the mRNA expressions and protein expressions of STAT3, SOCS1 are significantly eleveated in lesional skin compared with non-lesional skin, implying their roles in the pathophysiological process of psoriasis. Antagomir-155 lowers the expression of STAT3 and associated cytokines in lesional skin of murine psoriasis models possibly through the miRNA155-SOCS1 axis. MiR-155 is a possible target of treatment for psoriasis.