MiR-221-3p as a Potential Biomarker for Patients with Psoriasis and Its Role in Inflammatory Responses in Keratinocytes.

Introduction: This study investigated serum miR-221-3p levels in psoriatic patients and the characterization of serum miR-221-3p in keratinocyte inflammatory responses was further assessed.

Methods: qRT-PCR was used to detect the expression level of miR-221-3p in the serum of 46 patients with psoriasis and 42 healthy controls. The receiver operating characteristic curve evaluated the diagnostic ability of miR-221-3p in psoriasis. The effect of miR-221-3p on HaCaT cell proliferation was detected by using a cell counting Kit-8 and Transwell. ELISA was used to detect serum and keratinocyte pro-inflammatory factors.

Results: miR-221-3p was significantly increased in the serum of patients with psoriasis. The area under the curve was 0.861, the sensitivity was 80.4%, and the specificity was 85.7%. Serum miR-221-3p was positively correlated with the expression levels of tumor necrosis factor-α, interleukin (IL)-17A, and IL-22. Cell experiments showed that reducing the expression of miR-221-3p could significantly inhibit cell proliferation. Additionally, miR-221-3p downregulation also inhibited the release of some inflammatory factors in the HaCaT cells.

Discussion/conclusion: MiR-221-3p is a latent biomarker of psoriasis patients. Lower expression of miR-221-3p inhibits the cell proliferation and inflammatory responses of HaCaT cells, which offers a possible target for the therapeutic interventions of psoriasis.