Long non-coding RNAs in rheumatoid arthritis

Association of MTMR3 rs12537 at miR-181a binding site with rheumatoid arthritis and systemic lupus erythematosus risk in Egyptian patients

Single nucleotide polymorphisms (SNPs) in microRNA-target sites influence an individual's risk and prognosis for autoimmune diseases. Myotubularin-related protein 3 (MTMR3), an autophagy-related gene, is a direct target of miR-181a. We investigated whether MTMR3 SNP rs12537 in the miR-181a-binding site is associated with the susceptibility and progression of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Overall, 94 patients with RA, 80 patients with SLE, and 104 healthy volunteers were recruited. Genotyping and expression analysis of circulating MTMR3 and miR-181a were performed by qPCR. The autophagic marker MAP1LC3B was measured by ELISA. The rs12537 minor homozygote (TT) genotype was a candidate risk factor of both RA and SLE. rs12537TT was associated with lower serum MTMR3 expression and higher LC3B levels than other genotypes in patients with both diseases. Serum miR-181a expression was higher in rs12537TT carriers than in other genotypes among SLE patients. Serum miR-181a and MTMR3 levels were inversely correlated in SLE but not in RA patients. rs12537TT and serum miR-181a were positively associated with disease severity in both diseases. Our results identify a novel role of rs12537 in the susceptibility and progression of RA and SLE, possibly through impacting the interaction between miR-181a and MTMR3 leading to increased autophagy.

MALAT1-Driven Inhibition of Wnt Signal Impedes Proliferation and Inflammation in Fibroblast-Like Synoviocytes Through CTNNB1 Promoter Methylation in Rheumatoid Arthritis

Fibroblast-like synoviocytes (FLSs) participate in the pathogenesis of rheumatoid arthritis (RA). Emerging evidence has highlighted the role of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT1) and its potential involvement in RA. In this study, we test the hypothesis that the MALAT1 might inhibit proliferation and inflammatory response of FLSs in RA. The expression of MALAT1 was examined in synovial tissues from patients with RA. The effect of MALAT1 on cultured FLSs was analyzed by introducing overexpressed MALAT1 or short hairpin RNA (shRNA) against MALAT1. To validate whether methylation of CTNNB1 promoter was affected by MALAT1 alternation, we assessed the recruitment of DNA methyltransferases to CTNNB1 promoter. In cultured FLSs with shRNA-mediated CTNNB1 knockdown or activated Wnt signaling, we found the interaction between CTNNB1 and Wnt signaling. MALAT1 expression was reduced in synovial tissues of RA. MALAT1 could bind to CTNNB1 promoter region and recruit methyltransferase to promote CTNNB1 promoter methylation, thereby inhibiting CTNNB1. Notably, MALAT1 could suppress the transcription and expression of CTNNB1, thereby modulating the Wnt signaling pathway. Silenced MALAT1 stimulated the nucleation of β-catenin and the secretion of inflammatory cytokines including interleukin-6, interleukin-10, and tumor necrosis factor-α. Additionally, shRNA-mediated MALAT1 silencing elevated proliferation and suppressed apoptosis of FLSs accompanied. These findings provide evidence for the inhibitory effect of MALAT1 on proliferation and inflammation of FLSs by promoting CTNNB1 promoter methylation and inhibiting the Wnt signaling pathway. Therefore, this study provides a candidate therapeutic target for RA.

Molecular Characterization and Biological Function of a Novel LncRNA CRNG in Swine

Our previous study has showed that a novel gene is differentially expressed in the liver of cyadox-fed piglets, but its sequence and function are unknown. Here, rapid amplification of cDNA ends (RACE) and bioinformatics analysis showed that the novel gene is 953 bp without protein-coding ability and locates in chromosome 11. Hence, we identified the novel gene as long non-coding RNA (lncRNA) and named it cyadox-related novel gene (CRNG). Fluorescence in situ hybridization (FISH) showed that CRNG mainly distributes in cytoplasm. Moreover, microarray assay in combination with CRNG interference and overexpression showed that the differential genes such as ANPEP, KITLG, STAT5A, FOXP3, miR-451, IL-2, IL-10, IL-6, and TNF-α are mainly involved in viral and pathogens infection and the immune-inflammatory responses in PK-15 cells. This work reveals that CRNG might play a role in preventing the host from being infected by pathogens and viruses and exerting immune regulatory effects in the cytoplasm, which may be involved in prophylaxis of cyadox in piglets.

The Role of Histone Methyltransferases and Long Non-coding RNAs in the Regulation of T Cell Fate Decisions

T cell lineage decisions are critical for the development of proper immune responses to pathogens as well as important for the resolution of inflammatory responses. This differentiation process relies on a combination of intrinsic and extrinsic factors converging upon epigenetic regulation of transcriptional networks relevant to specific T cell lineages. As these biochemical modifications represent therapeutic opportunities in cancer biology and autoimmunity, implications of writers and readers of epigenetic marks to immune cell differentiation and function are highly relevant. Given the ready adoption of histone methyltransferase inhibitors in the clinic, we focus this review on the role of three histone modifying complexes: PRC-1, PRC-2, and G9A in modulating T cell fate decisions. Furthermore, we explore the role of long non-coding RNAs in regulating these processes, and discuss recent advances and challenges of implementing epigenetic therapies into clinical practice.

lncRNA NTT/PBOV1 Axis Promotes Monocyte Differentiation and Is Elevated in Rheumatoid Arthritis

Monocytes/macrophages are important in orchestrating inflammatory responses. However, knowledge of the long noncoding RNA (lncRNA) regulation of monocytic cell differentiation and diseases remains limited. We aimed to elucidate the role of the 17 kb lncRNA noncoding transcript in T cells (NTT) in monocyte functions. Knockdown and chromatin immunoprecipitation (ChIP) assays in THP-1 cells (human monocytic leukemia cell line) revealed that NTT is regulated by the monocyte key transcription factor C/EBPβ and that it binds to the promoter of nearby gene PBOV1 via hnRNP-U. Overexpression of PBOV1 in THP-1 cells resulted in cell cycle G1 arrest, differentiation into macrophages, a marked increase in IL-10 and CXCL10 mRNA levels, and upregulation of the costimulatory molecules. In contrast to the downregulated NTT observed in lipopolysaccharide (LPS)-treated THP-1 cells, the C/EBPβ/NTT/PBOV1 axis was found to be hyperactivated in peripheral blood mononuclear cells (PBMCs) of first-time diagnosed untreated early rheumatoid arthritis (RA) patients, and their gene expression levels decreased markedly after treatment. Higher initial C/EBPβ/NTT/PBOV1 expression levels were associated with a trend of higher disease activity DAS28 scores. In conclusion, our study suggests that the lncRNA NTT is a regulator of inflammation in monocytes, and its activation participates in monocyte/macrophage differentiation and the pathogenesis of RA.

LncRNA UCA1 sponges miR-204-5p to promote migration, invasion and epithelial-mesenchymal transition of glioma cells via upregulation of ZEB1

Long non-coding RNA urothelial carcinoma associated 1 (lncRNA UCA1) promotes cancer progression and enhances chemoresistance through miR-204-5p in a few cancers. However, no studies have investigated whether UCA1 regulates glioma metastasis through miR-204-5p and its target. In the present study, cell migration, invasion and epithelial-mesenchymal transition (EMT) were evaluated in glioma cells overexpressing UCA1. The relationships among UCA1, miR-204-5p and ZEB1 were examined by real-time PCR, western blotting and dual-luciferase reporter assays. The effect of UCA1 knockdown on xenograft tumor growth was investigated. The levels of miR-204-5p, fibronectin, COL5 A1 and ZEB1 in tumor tissues were also determined. The results showed that UCA1 overexpression promoted cell migration, invasion and EMT. UCA1 interacted with miR-204-5p and decreased its level. ZEB1 was identified as a direct target of miR-204-5p and miR-204-5p negatively regulated ZEB1 expression. Moreover, UCA1 sponged miR-204-5p and partially rescued the inhibitory effect of miR-204-5p on ZEB1. In our in vivo studies, UCA1 knockdown reduced tumor volume and tumor weight. In addition, the levels of fibronectin, COL5 A1 and ZEB1 were decreased, while miR-204-5p level was increased. The present study provides the first evidence that UCA1 promotes glioma metastasis through the miR-204-5p/ZEB1 axis, contributing to the understanding of the pathogenesis of glioma.

The Role of Long Non-coding RNAs in the Pathogenesis of RA, SLE, and SS

Rheumatoid diseases are a group of systemic autoimmune diseases which affect multiple organs with largely unknown etiology. In the past decade, long non-coding RNAs (lncRNAs) have emerged as important regulators of biological processes and contribute deeply to immune cell development and immune responses. Substantial evidences have been accumulated showing that LncRNAs involved in the pathogenesis of the rheumatoid diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS). In this review, we summarize literature combined with bioinformatics methods to analyze the unique and common lncRNAs patterns in rheumatoid diseases and try to reveal the important function of lncRNAs in RA, SLE and SS.

The prognostic value of long noncoding RNA Sox2ot expression in various cancers: A systematic review and meta-analysis

BACKGROUND

Several investigations have explored the prognostic value of long noncoding RNA Sox2 overlapping transcript (lncRNA Sox2ot) expression in human cancers, however, with inconsistent results. The aim of this study was to evaluate the prognostic role of lncRNA Sox2ot expression in various cancers.

METHODS

PubMed, Web of Science, Embase, and Cochrane Library were comprehensively searched to retrieve relevant studies. The relationships between lncRNA Sox2ot expression and prognostic parameters were detected, including overall survival (OS), tumor differentiation, clinical stage, distant metastasis, lymph node metastasis and so on.

RESULTS

A total of 10 studies involving 943 cancer patients were finally included into the study. High lncRNA Sox2ot expression was significantly related to shorter OS in cancers (HR = 2.06, 95%CI = 1.67-2.55, P < 0.01). The cancer patients with high lncRNA Sox2ot expression tended to have worse tumor differentiation (P = 0.04), advanced clinical stage (P < 0.01), earlier distant metastasis (P < 0.01), and earlier lymph node metastasis (P = 0.01) compared to those with low lncRNA Sox2ot expression. However, there was no distinct correlation between lncRNA Sox2ot expression and age (P = 0.87), gender (P = 0.48), tumor size (P = 0.08), or vascular invasion (P = 0.07).

CONCLUSION

High lncRNA Sox2ot expression was significantly associated with worse OS, advanced clinical stage, worse tumor differentiation, earlier distant metastasis, and earlier lymph node metastasis in various cancers. LncRNA Sox2ot expression might a promising prognostic factor in various cancers.

Long non-coding RNAs in rheumatoid arthritis

Rheumatoid arthritis, a disabling autoimmune disease, is associated with altered gene expression in circulating immune cells and synovial tissues. Accumulating evidence has suggested that long non-coding RNAs (lncRNAs), which modulate gene expression through multiple mechanisms, are important molecules involved in immune and inflammatory pathways. Importantly, many studies have reported that lncRNAs can be utilized as biomarkers for disease diagnosis and prognostication. Recently, dysregulation of lncRNAs in rheumatoid arthritis and other autoimmune diseases has been revealed. Experimental studies also confirmed their crosstalk with matrix metalloproteinases, nuclear factor-κB signalling and T-cell response pertinent to autoimmunity and inflammation. Circulating lncRNAs, such as HOTAIR, differentiated patients with rheumatoid arthritis from healthy subjects. Taken together, lncRNAs are good candidates as biomarkers and therapeutic targets in rheumatoid arthritis. Further investigation on in vivo delivery of these regulatory molecules and large-cohort validation of their clinical applicability may be useful.