LncRNA PICSAR promotes cell proliferation, migration and invasion of fibroblast-like synoviocytes by sponging miRNA-4701-5p in rheumatoid arthritis

EBioMedicine. 2019 Dec:50:408-420. doi: 10.1016/j.ebiom.2019.11.024. Epub 2019 Nov 30.

Abstract

Background: Long non-coding RNAs (lncRNAs) have drawn increasing attention because they play a pivotal role in various types of autoimmune diseases, including rheumatoid arthritis (RA). Fibroblast-like synoviocytes (FLSs), a prominent component of hyperplastic synovial pannus tissue, are the primary effector cells in RA synovial hyperplasia and invasion which can lead to joint destruction. In this study, we investigated whether lncRNAs could act as competing endogenous RNAs to regulate the pathological behaviors of RA-FLSs.

Methods: LncRNA microarray was conducted to establish lncRNA expression profiles in FLSs isolated from RA patients and healthy controls (HCs). Differentially expressed lncRNAs were verified by quantitative real-time PCR (qRT-PCR) on RA-FLSs and synovial fluid. The functional role of lncRNA PICSAR downregulation was evaluated in RA-FLSs. We conducted molecular biological analysis to predict miRNAs which have a potential binding site for PICSAR and further refined the results by qRT-PCR. Luciferase reporter assay was adopted to validate the interaction of lncRNA PICSAR and miR-4701-5p. Western Blot and qPCR were used to identify the target gene and protein. The functional role of miR-4701-5p upregulation was examined in RA-FLSs.

Findings: We identified a long intergenic non-protein-coding RNA162 (LINC00162), also known as lncRNA PICSAR (p38 inhibited cutaneous squamous cell carcinoma associated lincRNA), has significantly higher expression in RA-FLSs and RA synovial fluid. The cell proliferation, migration, invasion and proinflammatory cytokines production of RA-FLSs showed significant alterations after the lncRNA PICSAR suppression. Mechanistically, lncRNA PICSAR functioned through sponging miR-4701-5p in RA-FLSs.

Interpretation: Our results reveal PICSAR may exert an essential role in promoting synovial invasion and joint destruction by sponging miR-4701-5p in RA and that lncRNA PICSAR may act as a biomarker of RA.

Keywords: Fibroblast-like synoviocytes; Long non-coding RNAs; PICSAR; Rheumatoid arthritis.

MeSH terms

  • Arthritis, Rheumatoid / genetics*
  • Arthritis, Rheumatoid / metabolism
  • Arthritis, Rheumatoid / pathology
  • Arthritis, Rheumatoid / therapy
  • Cell Cycle
  • Cell Movement
  • Cell Proliferation
  • Cells, Cultured
  • Computational Biology / methods
  • Cytokines / metabolism
  • Female
  • Gene Expression Profiling
  • Gene Expression Regulation*
  • Gene Ontology
  • Humans
  • Male
  • MicroRNAs / genetics*
  • Middle Aged
  • Models, Biological
  • RNA Interference*
  • RNA, Long Noncoding / genetics*
  • Synoviocytes / metabolism*
  • Synoviocytes / pathology

Substances

  • Cytokines
  • MIRN4701 microRNA, human
  • MicroRNAs
  • RNA, Long Noncoding