Circulating microRNAs in autoimmune thyroid disease

Presentation Number: OR28-6
Date of Presentation: June 16th, 2013

Mitsuyasu Itoh*1, Hiroya Yamada2, Izumi Hiratsuka1 and Shuji Hashimoto3
1Fujita Health University, School of Medicine, Toyoake, Japan, 2Fujita Health Univ School of Med, Toyoake, Japan, 3Fujita Health University Sch of Med, Toyoake, Japan

Abstract

BACKGROUND:Autoimmune thyroid disease (AITD), such as Graves' disease (GD) and Hashimoto's thyroiditis (HT), is an archetype for organ-specific autoimmune diseases.  MicroRNAs (miRNAs) are small non-coding RNA, which can regulate gene expression at the post-transcriptional level. They have been reported to play a pivotal role in immune functions and in the development of autoimmunity and autoimmune disease. Recently, it has been recognized that specific circulating  miRNAs could serve as potential biomarkers of various disease. Moreover, the identification of circulating miRNAs can provide important and novel information of disease pathogenesis and clinical condition. However, circulating miRNAs in AITD has not yet been understood. This study aims to characterize the different circulating levels of miRNA from patients with AITD. METHODS:Thirty-one patients who met criteria for 15 GD, 22 HT, and 6 healthy controls were recruited. Microarray was used to analyze the expression patterns of miRNA in serum obtained from patients with GD or HT, and from healthy controls. After analyzing the microarray data, four interesting miRNA (miR-16, miR-22, miR-375, and miR-451) were selected and validated by SYBR Green-based quantitative real-time PCR in healthy controls, patients with GD, and those with HT. Relative expression quantification of each miRNA was calculated using the comparative cycle threshold (CT) method (2-ΔΔCT ), using spiked in cyn-39 as normalized internal control. RESULTS:There were several miRNAs expressed differently in serum from AITD patients compared with normal subjects by microarray analysis. Further analysis consistently showed that the expression of miR-22, miR-16, and miR-451 were increased in patients with GD. In addition, serum levels of miR-22 levels were decreased among patients with GD in remission. On the other hand, the expression levels of miR-375 were increased in patients with HT compared with those with GD and healthy controls. CONCLUSIONS:We revealed that different levels of serum miRNA were associated with GD or HD, which might play a role in the pathogenesis of GD and HD.

 

Nothing to Disclose: MI, HY, IH, SH