A Study of miRNA 223 Expression and its Correlation with Disease Severity in Chronic Plaque Psoriasis

BACKGROUND: Psoriasis is a chronic immune-mediated inflammatory disease affecting the skin and/or joints. MicroRNAs (miRNA) are single-stranded non-coding RNA molecules that bind to messenger RNA (mRNA) and regulate gene expression. Studies on peripheral blood mononuclear cells (PBMCs) in psoriatic patients showed an upregulation of miRNA 223. AIMS AND OBJECTIVES: a) To estimate and compare the expression of miRNA 223 in cases of chronic plaque psoriasis and controls. b) To correlate the expression of miRNA 223 with the severity of chronic plaque psoriasis. MATERIALS AND METHODS: This study included 80 subjects (40 with psoriasis and 40 with age- and sex-matched healthy controls) attending the dermatology OPD of a tertiary care hospital from January 2018 to June 2019. A detailed history, determination of Psoriasis Area Severity Index (PASI) score and estimation of miRNA 223 by quantitative real-time polymerase chain reaction (qRT-PCR), was done in all subjects. RESULTS: The expression of miRNA 223 (ΔCt) was higher in cases than in controls. The observed mean ΔCt was higher in severe (12.90 ± 0.46) than in mild (9.81 ± 1.70) and moderate (10.58 ± 1.26) psoriasis. The difference in expression of miRNA with varying severity of psoriasis was significant. The mean difference of ΔCt between mild to severe was (3.09) (P ≤ 0.001) and moderate to severe was (2.31) (P = 0.013). Among cases, the expression of miRNA 223 was higher in those exhibiting Koebner's phenomenon compared to those without Koebner's phenomenon (P = 0.0424). CONCLUSION: Expression of miRNA 223 was higher in psoriatic patients than in controls and the expression increased with the severity and activity of the disease suggesting the upregulation of miRNA 223 with the progression and activity of the disease.