Dataset Information

MicroRNA and mRNA profiling in the idiopathic inflammatory myopathies

ABSTRACT: Objectives: The idiopathic inflammatory myopathies (IIMs) are heterogeneous autoimmune conditions of skeletal muscle inflammation and weakness. MicroRNAs (miRNAs) are short, non-coding RNA which regulate gene expression of target mRNAs. The aim of this study was to profile miRNA and mRNA in IIM and identify miRNA-mRNA relationships which may be relevant to disease. Materials and methods: mRNA and miRNA in whole blood samples from 7 polymyositis (PM), 7 dermatomyositis (DM), 5 inclusion body myositis (IBM) and 5 non-myositis controls was profiled using next generation RNA sequencing. Gene ontology and pathway analyses were performed using GOseq and Ingenuity Pathway Analysis. Dysregulation of miRNAs and opposite dysregulation of predicted target mRNAs in IIM subgroups was validated using RTqPCR and investigated by transfecting human skeletal muscle cells with miRNA mimic. Results Analysis of differentially expressed genes showed that interferon signalling and anti-viral response pathways were upregulated in PM and DM compared to controls. An anti-Jo1 autoantibody positive subset of PM and DM (n=5) had more significant upregulation and predicted activation of interferon signalling and highlighted T-helper (Th1 and Th2) cell pathways. In miRNA profiling miR-96-5p was significantly upregulated in PM, DM and the anti-Jo1positive subset. RTqPCR replicated miR-96-5p upregulation and predicted mRNA target (ADK, CD28 and SLC4A10) downregulation. Transfection of a human skeletal muscle cell line with miR-96-5p mimic resulted in significant downregulation of ADK. Conclusion: MiRNA and mRNA profiling identified dysregulation of interferon signalling, anti-viral response and T-helper cell pathways, and indicates a possible role for miR-96-5p regulation of ADK in pathogenesis of IIM.

ORGANISM(S): Homo sapiens

PROVIDER: GSE125977 | GEO | 2019/07/31

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Objective: In idiopathic inflammatory myopathies (IIM) infiltration of immune cells into muscle and upregulation of MHC-I expression implies increased antigen presentation and involvement of the proteasome system. To decipher the role of immunoproteasomes in myositis, we investigated individual cell types and muscle tissues and focused on possible immune triggers. Methods: Expression of constitutive (PSMB5, -6, -7) and corresponding immunoproteasomal subunits (PSMB8, -9, -10) was analyzed by real-time RT-PCR in muscle biopsies and sorted peripheral blood cells of patients with IIM, non-inflammatory myopathies (NIM) and healthy donors (HD). Protein analysis in muscle biopsies was performed by western blot. Affymetrix HG-U133 platform derived transcriptome data from biopsies of different muscle diseases and from immune cell types as well as monocyte stimulation experiments were used for validation, coregulation and coexpression analyses. Results: Real-time RT-PCR revealed significantly increased expression of immunoproteasomal subunits (PSMB8/-9/-10) in DC, monocytes and CD8+ T-cells in IIM. In muscle biopsies, the immunosubunits were elevated in IIM compared to NIM and exceeded levels of matched blood samples. Proteins of PSMB8 and -9 were found only in IIM but not NIM muscle biopsies. Reanalysis of 78 myositis and 20 healthy muscle transcriptomes confirmed these results and revealed involvement of the antigen processing and presentation pathway. Comparison with reference profiles of sorted immune cells and healthy muscle confirmed upregulation of PSMB8 and -9 in myositis biopsies beyond infiltration related changes. This upregulation correlated highest with STAT1, IRF1 and IFNγ expression. Elevation of T-cell specific transcripts in active IIM muscles was accompanied by increased expression of DC and monocyte marker genes and thus reflects the cell type specific involvement observed in peripheral blood. Conclusions: Immunoproteasomes seem to indicate IIM activity and suggest that dominant involvement of antigen processing and presentation may qualify these diseases exemplarily for the evolving therapeutic concepts of immunoproteasome specific inhibition.

Project description:Aberrant changes in microRNAs (miRNAs) contribute to lymphomagenesis and represent potential therapeutic targets. OTX015 (MK-8628), a bromodomain and extra-terminal domain (BET) inhibitor (BETi), has demonstrated preclinical and clinical activity in haematological tumours. To better understand the mechanism of action of OTX015 we studied its effects on miRNAs in lymphomas. We performed miRNA profiling of DLBCL cells treated with OTX015 and observed changes in the expression levels of a subset of miRNAs, including miR-92a-1-5p, miR-21-3p, miR-155-5p and miR-96-5p, which are known to play a role in lymphomagenesis and/or resistance to chemotherapy. Analysis of publicly available BRD4 ChIP-Seq data of DLBCL cells treated with the BETi JQ1 showed that BRD4 was bound to the upstream regulatory regions of multiple miRNA genes and that this binding decreased following BETi. Alignment of our miRNA profiling data with the BRD4 ChIP-Seq data revealed that many miRNAs downregulated by OTX015 also exhibited reduced BRD4 binding in their promoter regions following BETi treatment, indicating that BRD4 directly modulated miRNA expression in lymphoma. Among the miRNAs upregulated in response to OTX015 was miR-96-5p, a miRNA known to play a role in B-cell transformation. In lymphomas, miR-96-5p transcription is repressed by the arginine methyltransferase PRMT5. In turn, PRMT5 translation is inhibited by miR-96-5p. We demonstrated that BRD4 bound to the 5’ regulatory region of PRMT5 and that following BET inhibition PRMT5 expression decreased, BRD4 binding to the 5’ region of PRMT5 was reduced and enrichment of PRMT5 at the miR-96-5p promoter lessened. Our results demonstrate that BRD4 binds to the promoters of miRNA genes to directly modulate their expression in lymphoma cells and that BETi administration results in decreased binding of BRD4 to the promoters of specific miRNAs to reduce their expression. Additionally, we show that BETi treatment can affect the expression of genes that control miRNA transcription to indirectly modulate miRNA expression. The data presented here indicate that the ability of BETi to inhibit or activate specific signalling pathways and processes critical to lymphoma cell proliferation and survival is in part due to changes in miRNA expression.

Project description:Objective: In idiopathic inflammatory myopathies (IIM) infiltration of immune cells into muscle and upregulation of MHC-I expression implies increased antigen presentation and involvement of the proteasome system. To decipher the role of immunoproteasomes in myositis, we investigated individual cell types and muscle tissues and focused on possible immune triggers. Methods: Expression of constitutive (PSMB5, -6, -7) and corresponding immunoproteasomal subunits (PSMB8, -9, -10) was analyzed by real-time RT-PCR in muscle biopsies and sorted peripheral blood cells of patients with IIM, non-inflammatory myopathies (NIM) and healthy donors (HD). Protein analysis in muscle biopsies was performed by western blot. Affymetrix HG-U133 platform derived transcriptome data from biopsies of different muscle diseases and from immune cell types as well as monocyte stimulation experiments were used for validation, coregulation and coexpression analyses. Results: Real-time RT-PCR revealed significantly increased expression of immunoproteasomal subunits (PSMB8/-9/-10) in DC, monocytes and CD8+ T-cells in IIM. In muscle biopsies, the immunosubunits were elevated in IIM compared to NIM and exceeded levels of matched blood samples. Proteins of PSMB8 and -9 were found only in IIM but not NIM muscle biopsies. Reanalysis of 78 myositis and 20 healthy muscle transcriptomes confirmed these results and revealed involvement of the antigen processing and presentation pathway. Comparison with reference profiles of sorted immune cells and healthy muscle confirmed upregulation of PSMB8 and -9 in myositis biopsies beyond infiltration related changes. This upregulation correlated highest with STAT1, IRF1 and IFNM-NM-3 expression. Elevation of T-cell specific transcripts in active IIM muscles was accompanied by increased expression of DC and monocyte marker genes and thus reflects the cell type specific involvement observed in peripheral blood. Conclusions: Immunoproteasomes seem to indicate IIM activity and suggest that dominant involvement of antigen processing and presentation may qualify these diseases exemplarily for the evolving therapeutic concepts of immunoproteasome specific inhibition. Investigation of constitutive and immunoproteasomal subunit expression in muscle tissue of patients with inflammatory and non-inflammatory myopathies These transcriptomes were used as reference signatures of different immune cell types in order to estimate the contribution of immune cell transcripts to the muscle transcriptomes investigated in the datasets GSE2044, GSE3112, GSE5370, GSE39454, GSE3307, GSE13205, GSE10685.

Dataset Information

MicroRNA and mRNA profiling in the idiopathic inflammatory myopathies

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets