The miR-338-3p expression level in pemphigus diagnosis

Abstract

BACKGROUND: Pemphigus is a group of potentially fatal chronic cutaneous diseases in which blisters appear on the skin and mucous membranes as a result of IgG autoantibodies binding to desmosomes in the epidermis, leading to keratinocytes acantholysis. Currently, methods to monitor disease activity and therapy efficiency using various biomarkers are being investigated. MicroRNA expression, in particular miR-338-3p, has been one of these biomarkers, as changes in miR-338-3p expression may trigger the Th1/Th2 cell imbalance and possibly be involved in the pathogenesis of the disease. AIMS: This study aimed to design a protocol to evaluate the level of miR-338-3p expression in peripheral blood mononuclear cells and verify the diagnostic value of miR-338-3p expression in pemphigus. MATERIALS AND METHODS: Experimental prospective comparative study was conducted from February 2023 to February 2024 at the Dermatology Department of Sechenov University. The study included 10 patients with pemphigus in the active stage of the disease, 3 patients in remission, and 9 participants of the control group. The expression of miRNA-338-3p was analyzed by qRT-PCR, cDNA was obtained using StemLoop method. The evaluation of miRNA-338-3p expression level was based on its comparison with the expression of U6 gene using 2-ΔΔСT method. RESULTS: The expression level of miR-338-3p was analyzed in 10 patients in the active stage of the disease (5 men (50%), 5 women (50%); mean age 46 ± 10.7 years), 3 patients in remission (2 women (66.5%), 1 man (33.5%); mean age 57 ± 8 years), 9 control group (8 women (88.5%), 1 man (11.5%); mean age 36 ± 16.8 years). The mean expression level of miR-338-3p was 8.64 (SD ± 5.72) in patients with active disease, 3.38 (SD ± 1.44) in patients in remission, and 1.48 (SD ± 1.12) in controls. A statistically significant increase in the expression level of miR-338-3p was found in patients in the active disease stage compared to the control group (p = 0.002). A statistically significant correlation was found between the level of miR-338-3p expression and the PDAI index score (p 0.001). CONCLUSIONS: Based on the data obtained in this study, it can be assumed that microRNAs are important in pemphigus, and miR-338-3p expression in particular may serve as a key element in pemphigus pathogenesis. More detailed study of microRNAs and analysis of expression variability according to clinical data may provide the basis for developing new diagnostic methods and severity scoring, allowing more accurate and less invasive diagnostic methods, as well as monitoring and predicting disease progression.