Plasma Long Non-Coding RNA Expression Profiles in Patients with Rheumatoid Arthritis

Recently, long non-coding RNAs (lncRNAs) have attracted substantial attention owing to their unforeseen critical roles in a wide range of biological processes. The aim of our study was to provide an overview of lncRNA expression profiles in plasma of RA patients.

The Agilent LncRNA + mRNA Human Gene Expression Microarray V4.0 was employed to determine differentially expressed (DE) lncRNAs and mRNAs in plasma of four female newly diagnosed and DMARD-naïve RA patients and four female age-matched healthy controls. The KOBAS (KEGG Orthology Based Annotation System) software was applied to determine the gene ontology (GO) terms and pathway in which the DE mRNAs were enriched. Furthermore, a lncRNA-mRNA co-expression network was constructed according to the correlation between DE lncRNAs and mRNAs.

Compared with healthy controls, a total of 289 DE lncRNAs (169 up-regulated and 120 down-regulated) and 468 DE mRNAs (280 up-regulated and 188 down-regulated) were found in the plasma of patients with RA. Bioinformatics analysis indicated that the DE mRNAs might be involved in the pathogenesis of RA mainly through platelets. In addition, a co-expression network composed of 229 network nodes and 340 connections between 116 lncRNAs and 113 mRNAs was constructed.

We characterized the plasma lncRNA expression profiles in RA patients for the first time. Our results could shed new light on the pathogenesis of RA and help identify lncRNAs as novel diagnostic biomarkers and therapeutic targets for RA.