Study On The Regulation Of P63and SOCS3by MiR-203in HaCaT Cells

Objective: Psoriasis is an autoimmune disease that appears on the skin. Andpathogenesis that leads to the epidermal proliferation and differentiation is unclear. Ithas been revealed that STAT3played a critical role in signaling pathway in psoriasis bysitulating cell proliferation, inhibiting apoptosis, as well as mediating mutual responsebetween keratinocytes and leucocytes. Recently discovered microRNAs (miRNAs) are aclass of endogenous, small non-encoding RNAs. Their primary function was believed asinhibiting translation of proteins coding mRNAs at post-transcriptional level. miR-203,the first skin-specific miRNA, is over-expressed in the psoriatic lesional skin. SOCS3and p63, which are two important regulators of STAT3and Notch signal transductionpathways are believed as target genes of miR-203. However, the mechanism ofregulating STAT3and Notch by miR-203in psoriasis is not clear now.The present study tested the expression profiles of the above proteins to identifyregulation mechanism. Expression profile will be compared between miR-203overexpressed and inhibited HaCaT cells through transfection of in vitro culturedHaCaT cells with miR-203mimic and inhibitor. Changing of p63, STAT3and Notch1has been shown to correlate with psoriasis. The study will provide basis for noveltherapies of psoriasis.Methods: miR-203mimics and inhibitors were used to transfect HaCaT cells,qRT-PCR, Western blot, FCM methods were used to analyze the mRNA and proteinsexpression of p63, SOCS3, p-STAT3and Notch1in HaCaT cells after transfection;Then HaCaT cells were cultured with culture medium containing TNF-α (20ng/ml) andIL-6(20ng/ml). And the miR-203expression was detected by qRT-PCR.Results:1. We observed the effects of miR-203on p63, SOCS3, p-STAT3andNotch1by qRT-PCR. There were up-regulation tendency of SOCS3and p-STAT3as well as Notch1in miR-203mimic transfection.2. The results of Western blot methodshowed that the expression of p-STAT3and Notch1shared the same expressingtendency, they all expressed highly in miR-203mimic transfection.3. The expression ofmiRNA-203increased after cells were cultured with TNF-α and IL-6.Conclusion: The results suggest that overexpression of miR-203down-regulatedthe expression of p63and SOCS3, so that STAT3was activated and STAT3phosphorylation level was increased. It may establish an experimental foundation toelucidate the regulatory mechanism of p63and SOCS3, and explore the relationship ofSTAT3signaling pathway with miR-203. That will be useful to understand the role ofmiR-203in the pathogenesis of psoriasis.