Acta Dermato-Venereologica 99-6CompleteContent | Page 15

INVESTIGATIVE REPORT Serum miR-125a-5p and CCL17 Upregulated in Chronic Spontaneous Urticaria and Correlated with Treatment Response Liming ZHANG, Ruiqun QI, Yang YANG, Xinghua GAO, Hongduo CHEN and Ting XIAO Department of Dermatology, The First Hospital of China Medical University, National Health Commission Key Laboratory of Immunodermatology, Key Laboratory of Immunodermatology of Ministry of Education, Shenyang, China Chronic spontaneous urticaria (CSU) is a common skin disorder associated with autoimmunity. Micro­ RNAs (miRNAs) are endogenous noncoding RNA mo- lecules reported to be potential biomarkers for some autoimmune diseases. In this study, we investigated the association of miRNAs with CSU. A quantitative PCR (qPCR)-based array was generated from sera as obtained from 20 active CSU patients and 20 healthy controls. Upregulated or downregulated miRNAs were validated by reverse transcription qPCR in sera from 59 active CSU patients and 58 healthy controls. The ex- pression of miR-125a-5p was significantly upregulated in CSU sera and serum levels of CCL17 were also signi- ficantly increased in CSU patients. Serum miR-125a-5p expressions were found to be further upregulated in refractory CSU cases (n  = 10). In 12 CSU patients in remission, serum miR-125a-5p expression and CCL17 levels were significantly decreased as compared with that obtained in active phase patients. These results indicated that miR-125a-5p and CCL17 can serve as potential serum biomarkers for CSU. Key words: chronic spontaneous urticaria; chronic idiopathic urticaria; miR-125a-5p; CCL17; IL-17. Accepted Feb 26, 2019: E-published Feb 27, 2019 Acta Derm Venereol 2019; 99: 571–578. 571 Corr: Ting Xiao and Hongduo Chen, Department of Dermatology,
The First Hospital of China Medical University, No. 155 Nanjing Bei Street, Shenyang 110001, China.
E-mails: [email protected]; hongduochen@ hotmail.com. C hronic spontaneous urticaria (CSU) is defined as the spontaneous recurrence of itchy wheals and/ or angioedema that are present for > 6 weeks in the ab- sence of any apparent causes (1). CSU generally has a prolonged duration of 1 to 5 years and exerts a profound impact on the patients’ quality of life. The prevalence of CSU is approximately 1.8% of the adult population (2). A subset of CSU is considered to be an autoimmune disease. Circulating autoantibodies including anti-IgE, anti-FcɛRI, anti-thyroglobulin (TG) or anti-thyroid per- oxidase (TPO) have been found in patients with CSU. However, these autoantibodies are not CSU-specific and therefore, cannot serve as biomarkers reflecting disease severity and treatment responses. A number of parameters have been reported to be increased within the sera or plasma of patients with CSU, but few have been generally confirmed as being specifically related to SIGNIFICANCE Currently, there exist no generally accepted objective bio- markers for chronic spontaneous urticaria. Therefore, the identification of new categories of biomarkers for chronic spontaneous urticaria are urgently needed. To the best of our knowledge, no published information is available regar- ding serum miRNA as related to chronic spontaneous urti- caria. In this study, we provide new and important findings which show that serum expression of miR-125a-5p and CCL17 are significantly upregulated in patients with active chronic spontaneous urticaria and significantly decreased in the remission phase. Moreover, a further upregulation in serum miR-125a-5p expression was observed in refractory chronic spontaneous urticaria cases. These results high- light the significance of miR-125a-5p and CCL17 as poten- tial serum biomarkers for chronic spontaneous urticaria. CSU (3). Accordingly, there is a lack of objective and specific biomarkers for CSU and the identification of such biomarkers is urgently needed for this condition. MicroRNAs (miRNAs) are endogenous ~22nt non- coding RNA (ncRNA) molecules that decrease targeted mRNA levels and/or reduce expression of their cog- nate target proteins. They can accomplish these effects through a number of different mechanisms including RNA degradation, induced decapping/deadenylation, altered cap protein binding, reduced ribosome occupancy, and/or sequestration of mRNA from translational machi- nery. MiRNAs, either alone or in combination with other known biomarkers, have been used as diagnostic tools in many studies (4). As secreted miRNAs remain stable in body fluids, they are more readily available for assay and less invasive than biopsies. These advantages make them a very appealing diagnostic instrument. Th2-mediated immune pathways induce mast cell ac- tivation and degranulation via IgE antibody production and its binding to the Fcε receptor (FcεR) (5). Th17 cells show both inhibitory and stimulatory effects on antibody production by mast cells (6). Of particular relevance to the current study are the recent findings revealing that Th2/ Th17 cytokines, transcription factors and Th2 chemo­kines are upregulated or elevated in CSU patients’ skin lesions, plasma and serum, respectively (7–10). Accordingly, Th2 and Th17 pathways may be involved in the pathogenesis of CSU, and CCL17 and IL-17 can serve as serum mar- kers of Th2 and Th17 inflammation, respectively. This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Journal Compilation © 2019 Acta Dermato-Venereologica. doi: 10.2340/00015555-3149 Acta Derm Venereol 2019; 99: 571–578