Long noncoding RNAs expression profile in patients with rheumatoid arthritis

Long noncoding RNAs (lncRNAs) belong to a new class of noncoding RNAs. Emerging evidence has shown that lncRNAs play a crucial role in the regulation of autoimmunity. During the past few years, the modifying effects of lncRNAs in rheumatoid arthritis (RA) have drawn much attention. However, the underlying molecular mechanisms involved in RA pathogenesis remain largely unknown. Herein, we aim to investigate the expression profile of lncRNAs in patients with RA and identify promising targets for RA diagnosis and treatment.Microarray screening and real-time PCR of lncRNAs were performed in the serum from 3 RA patients and 3 healthy controls. Significantly differentially expressed lncRNAs were selectively verified in 43 RA patients and 40 healthy controls by real-time PCR. LncRNA-mRNA co-expression and gene-pathway networks were assured in the bioinformatics analysis.After microarray analysis, there were a total of 73 up-regulated and 61 down-regulated lncRNAs as well as 128 up-regulated and 37 down-regulated mRNAs in the serum of RA patients. After validated by real-time PCR, 5 of these lncRNAs were found to be significantly up-regulated in the serum of RA patients including RNA143598, RNA143596, HIX0032090, IGHCgamma1, and XLOC_002730. Significant association was observed between these lncRNAs and the disease course, erythrocyte sedimentation rate (ESR), rheumatoid factor (RF) as well as anti-cyclic citrullinated peptide (anti-CCP) antibody. Computational analysis revealed that 55 of the differentially expressed mRNAs were associated with 41 lncRNAs involved in signaling pathways of toll like receptors (TLRs), nuclear factor-kappa B (NF-κB), and cytokine, especially the IRF3/IRF7 mediated signaling transduction. Microarray screening and real-time PCR of lncRNAs were performed in the serum from 3 RA patients and 3 healthy controls. Significantly differentially expressed lncRNAs were selectively verified in 43 RA patients and 40 healthy controls by real-time PCR.