Project description:Stratifying patients on the basis of molecular signatures could facilitate development of therapeutics that target pathways specific to a particular disease or tissue location. Previous studies suggest that pathogenesis of rheumatoid arthritis (RA) is similar in all affected joints. Here we show that distinct DNA methylation and transcriptome signatures not only discriminate RA fibroblast-like synoviocytes (FLS) from osteoarthritis FLS, but also distinguish RA FLS isolated from knees and hips. Using genome-wide methods, we show differences between RA knee and hip FLS in the methylation of genes encoding biological pathways, such as IL-6 signaling via JAK-STAT pathway. Furthermore, differentially expressed genes are identified between knee and hip FLS using RNA-seq. Double-evidenced genes that are both differentially methylated and expressed include multiple HOX genes. Joint-specific DNA signatures suggest that RA disease mechanisms might vary from joint to joint, thus potentially explaining some of the diversity of drug responses in RA patients.
Project description:Stratifying patients on the basis of molecular signatures could facilitate development of therapeutics that target pathways specific to a particular disease or tissue location. Previous studies suggest that pathogenesis of rheumatoid arthritis (RA) is similar in all affected joints. Here we show that distinct DNA methylation and transcriptome signatures not only discriminate RA fibroblast-like synoviocytes (FLS) from osteoarthritis FLS, but also distinguish RA FLS isolated from knees and hips. Using genome-wide methods, we show differences between RA knee and hip FLS in the methylation of genes encoding biological pathways, such as IL-6 signaling via JAK-STAT pathway. Furthermore, differentially expressed genes are identified between knee and hip FLS using RNA-seq. Double-evidenced genes that are both differentially methylated and expressed include multiple HOX genes. Joint-specific DNA signatures suggest that RA disease mechanisms might vary from joint to joint, thus potentially explaining some of the diversity of drug responses in RA patients.
Project description:Rheumatoid arthritis (RA) fibroblast‐like synoviocytes (FLS) derived from hip and knee have distinctive DNA methylation and transcriptome patterns in interleukin (IL)‐6 signaling and Janus kinase (JAK)–signal transducers and activators of transcription (STAT) pathways. To determine the functional effects of these joint‐specific signatures, we evaluated how RA hip and knee FLS differ in their response to IL‐6.Hip or knee RA FLS were obtained after arthroplasty. Previously published datasets on epigenetic landscape of FLS were mined to identify joint‐specific IL‐6–related epigenomic differences. RNA sequencing was performed on five RA hip and five knee FLS treated with or without IL‐6. Differential gene expression was determined using edgeR software. STAT3 phosphorylation was measured using bead assays. Sensitivity to tofacitinib was evaluated by measuring CCL2 inhibition using quantitative polymerase chain reaction. Assay for Transposase‐Accessible Chromatin sequencing and histone chromatin immunoprecipitation sequencing datasets from RA FLS were analyzed to identify epigenomic differences between hip and knee. Differential chromatin accessibility was associated with IL‐6, IL‐6R, and JAK1 genes. H3K27ac was also differentially marked at other JAK‐STAT–related genes, including STAT3‐STAT5A region. Principal component analysis of RNA sequencing data confirmed segregation between RA hip and knee FLS under basal conditions, that persisted following IL‐6 treatment. STAT3 phosphorylation after IL‐6 was significantly higher in knee than hip FLS and was highly correlated with JAK1 protein levels. Knee FLS were less sensitive to the JAK inhibitor tofacitinib than hip FLS. RA hip and knee FLS have distinct transcriptomes, epigenetic marks, and STAT3 activation patterns in the IL‐6 pathway. These joint‐specific differences might contribute to a differential clinical response in individual joints to targeted therapies such as JAK inhibitors.
Project description:Background. Rheumatoid arthritis (RA) is a chronic inflammatory and destructive joint disease, characterized by overexpression of pro-inflammatory/-destructive genes and other activating genes (e.g., proto-oncogenes) in the synovial membrane (SM). The gene expression in disease is often characterized by significant inter-individual variances via specific synchronization/ desynchronization of gene expression. To elucidate the contribution of the variance to the pathogenesis of disease, expression variances were tested in SM samples of RA patients, osteoarthritis (OA) patients, and normal controls (NC). Results. For the comparison between RA and NC, 568 genes with significantly different variances in the 2 groups (p < 0.05; Bonferroni/Holm corrected Brown-Forsythe version of the Levene-Test) were selected. For the comparison between RA and OA, 333 genes were selected. Using the Kyoto encyclopedia of genes and genomes (KEGG), 10 pathways/complexes significantly affected by higher gene expression variances were identified in RA compared to NC, including cytokine – cytokine receptor interactions, the TGF-pathway, and anti-apoptosis. Compared to OA, 3 pathways with significantly higher variances were identified in RA (e.g., B cell receptor signaling, VEGF signaling). Functionally, the majority of the identified pathways is involved in the regulation of inflammation, proliferation, cell survival, and angiogenesis. Conclusion. In RA, a number of disease-relevant or even disease-specific pathways/complexes are characterized by broad intra-group, inter-individual expression variances. This indicates that RA pathogenesis in different individuals may depend to a lesser extent on common alterations of the expression of specific key genes, but on individual-specific alterations of different genes resulting in common disturbances of key pathways.
Project description:Rheumatoid arthritis (RA) is a common chronic inflammatory joint disease characterized by persistent synovial hyperplasia and progressive destruction of joint cartilage and bone.Fibroblast-like synoviocytes (FLSs), a prominent component of hyperplastic synovial pannus tissue, are the primary effector cells in RA synovial hyperplasia and invasion. However, the underlying molecular mechanisms remain unclear. Here, we apply transcriptome to assay the regulatory networks which contribute to the proliferation, migration and invasion of RA-FLSs .
Project description:Proper retinoic acid (RA) signaling is essential for normal craniofacial development. Both excessive RA and RA deficiency in early embryonic stage led to a variety of craniofacial malformations, e.g., cleft palate, which have been investigated extensively. Dysregulated Wnt and Shh signaling were shown to underlie the pathogenesis of RA-induced craniofacial defects. In our present study, we showed a spatiotemporal-specific effect of RA signaling in regulating early development of facial prominences. While inhibited the Wnt activities in E12.5/E13.5 mouse palatal shelves, early exposure of excessive RA induced Wnt signaling and Wnt-related gene expression in mouse embryonic Frontonasal/Maxillary processes. A conserved regulatory network of miR-484-Fzd5 was identified to play critical roles in RA regulated craniofacial development using RNA-seq.
Project description:Proper retinoic acid (RA) signaling is essential for normal craniofacial development. Both excessive RA and RA deficiency in early embryonic stage led to a variety of craniofacial malformations, e.g., cleft palate, which have been investigated extensively. Dysregulated Wnt and Shh signaling were shown to underlie the pathogenesis of RA-induced craniofacial defects. In our present study, we showed a spatiotemporal-specific effect of RA signaling in regulating early development of facial prominences. While inhibited the Wnt activities in E12.5/E13.5 mouse palatal shelves, early exposure of excessive RA induced Wnt signaling and Wnt-related gene expression in mouse embryonic Frontonasal/Maxillary processes. A conserved regulatory network of miR-484-Fzd5 was identified to play critical roles in RA regulated craniofacial development using RNA-seq.
Project description:All the synovial tissue specimens for TMT relative quantitative proteomics and further experiments were obtained from the patients with RA or OA undergoing surgical joint replacement at the clinical of joint surgery (Xi'an Hong Hui Hospital, Xi'an Jiaotong University, China). The diagnosis of the patients were accorded to the criteria of the American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) in 2010.a quantitative proteomic profiling of synovial tissue obtained from RA and OA patients was carried out by using TMT labeling followed by high resolution mass spectrometry analysis. We have identified 4822 proteins out of which 510 proteins were found to be differentially expressed by ≥1.2 fold change in the synovial tissue from RA verses OA patients.