Project description:In this study, we demonstrated that baseline SOX11 expression was significantly higher in dermal fibroblasts (DFs) isolated from patients with SSc than that in controls, and increased in response to TGF-b. We then showed that SOX11 is involved in the expression of periostin and some periostin-dependent fibrotic factors identified in lung fibroblasts previously. Moreover, we identified some fibrotic factors induced by SOX11 in DNA microarrays combining TGF-b induction and SOX11 knockdown. Finally, we showed that genetic deletion of SOX11 in Postn positive fibroblast cells protects from bleomycin (BLM)-induced skin fibrosis. Altogether, our data indicate that SOX11 and periostin forms a vicious circle and that TGF-b activates this circle specifically in SSc dermal fibroblasts.
Project description:In this study, two gene expression analyses were performed. The first analysis, comparing the DEGs between fibrotic and non-fibrotic tissue, revealed genes which may play a role in testicular fibrosis, including VCAM1. In addition, this analysis revealed a pertinent role for genes involved in the TGF-β1 pathway. Secondly, a differential gene expression analysis between KS and TA samples was performed. GO analysis revealed genes involved in the chronic inflammatory responses. When comparing the X-linked genes of the first analysis (fibrotic versus non-fibrotic) with those of the second analysis (KS versus TA), X-linked fibrotic genes involved in KS revealed, i.e. MXRA5, DCX and VCX3B. Their potential role in KS-related testicular fibrosis needs further study.
Project description:The neural transcription factor SOX11 is overexpressed in aggressive lymphoid neoplasms mainly in mantle cell lymphoma (MCL). We have recently demonstrated SOX11 tumorigenic potential in vivo by showing a significant reduction on tumor growth of SOX11-knockdown MCL cells in xenograft experiments, confirming the clinical observations that SOX11 may play an important role in the aggressive behavior of MCL (Vegliante et al., 2013). However, the specific mechanisms regulated by SOX11 that promote the oncogenic and rapid tumor growth of aggressive MCL still remain to be elucidated. To further characterize the potential oncogenic mechanisms regulated by SOX11 in MCL, we have analyzed the GEP derived from the xenograft SOX11-positive and knockdown xenograft derived tumors. Differential gene expression between SOX11-positive Z138 and SOX11-negative Z138 MCL cell lines xenotransplanted in SCID mices derived tumors.
Project description:Background/Aims: There is a major unmet need to assess prognostic impact of anti-fibrotics in clinical trials due to the slow rate of liver fibrosis progression. We aimed to develop a surrogate biomarker to predict future fibrosis progression. Methods: A Fibrosis Progression Signature (FPS) was defined to predict fibrosis progression within 5 years in HCV and NAFLD patients with no to minimal fibrosis at baseline (n=421), and validated in an independent NAFLD cohort (n=78). The FPS was used to assess response to 13 candidate anti-fibrotics in organotypic ex vivo cultures of clinical fibrotic liver tissues (n=78), and cenicriviroc in NASH patients enrolled in a clinical trial (n=19, NCT02217475). A serum-protein-based surrogate FPS (FPSec) was developed and technically evaluated in a liver disease patient cohort (n=79). Results: A 20-gene FPS was defined and validated in an independent NAFLD cohort (aOR=10.93, AUROC=0.86). Among computationally inferred fibrosis-driving FPS genes, BCL2 was confirmed as a potential pharmacological target using clinical liver tissues. Systematic ex vivo evaluation of 13 candidate anti-fibrotics identified rational combination therapies based on epigallocatechin gallate, some of which were validated for enhanced anti-fibrotic effect in ex vivo culture of clinical liver tissues. In NASH patients treated with cenicriviroc, FPS modulation was associated with 1-year fibrosis improvement accompanied by suppression of the E2F pathway. Induction of PPARalpha pathway was absent in patients without fibrosis improvement, suggesting benefit of combining PPARalpha agonism to improve anti-fibrotic efficacy of cenicriviroc. A 7-protein FPSec panel showed concordant prognostic prediction with FPS. Conclusion: FPS predicts long-term fibrosis progression in an etiology-agnostic manner, which can inform anti-fibrotic drug development.
Project description:The neural transcription factor SOX11 is overexpressed in aggressive lymphoid neoplasms mainly in mantle cell lymphoma (MCL). We have recently demonstrated SOX11 tumorigenic potential in vivo by showing a significant reduction on tumor growth of SOX11-knockdown MCL cells in xenograft experiments, confirming the clinical observations that SOX11 may play an important role in the aggressive behavior of MCL (Vegliante et al., 2013). However, the specific mechanisms regulated by SOX11 that promote the oncogenic and rapid tumor growth of aggressive MCL still remain to be elucidated. To further characterize the potential oncogenic mechanisms regulated by SOX11 in MCL, we have analyzed the GEP derived from the xenograft SOX11-positive and knockdown xenograft derived tumors. Differential gene expression between SOX11-positive Z138 and SOX11-negative Z138 MCL cell lines xenotransplanted in SCID mices derived tumors. To determine the transcriptional programs regulated by SOX11 we first generated a MCL cellular model with reduced SOX11 protein levels by infecting MCL cell lines with lentiviral particles carrying shRNA plasmids specifically targeting SOX11 (shSOX11.1 and shSOX11.3). Next, CB17-severe combined immunodeficient (CB17-SCID) mice (Charles River Laboratory, Wilmington, MA) were subcutaneously inoculated into their lower dorsum with Z138 shSOX11.1, shSOX11.3, shControl in Matrigel basement membrane matrix and compared the GEP of SOX11-positive and SOX11-negative MCL xenotransplant derived tumors using the Affymetrix U133+2.0 microarrays.
Project description:We used the scRNA-seq to characterize disease-related heterogeneity within cell populations of macrophages/monocytes in the bronchoalveolar lavage fluid from West Highland white terriers either healthy or affected with canine idioapthic pulmonary fibrosis. The disease is still not well understood, occurs in old West Highland white terriers and results from deposition of fibrotic tissue in the lung parenchyma causing respiratory failure.
Project description:The neural transcription factor SOX11 is overexpressed in aggressive lymphoid neoplasms mainly in mantle cell lymphoma (MCL), but its functional role in malignant B-cells is unknown. To identify target genes transcriptionally regulated by SOX11 in malignant lymphoid cells, we have used Gene Expression Profiling (GEP) after SOX11 silencing in MCL cell lines.
Project description:Idiopathic pulmonary fibrosis (IPF) is the prototypic progressive fibrotic lung disease with a median survival of 2-4 years. Injury to and/or dysfunction of alveolar epithelium are strongly implicated in IPF disease initiation, but what factors determine why fibrosis progresses rather than normal tissue repair occurs remain poorly understood. We previously demonstrated that ZEB1-mediated epithelial-mesenchymal transition (EMT) in human alveolar epithelial type II (ATII) cells augments TGF-β-induced profibrogenic responses in underlying lung fibroblasts by paracrine signalling. Here we investigated bi-directional epithelial-mesenchymal crosstalk and its potential to drive fibrosis progression. RNA sequencing (RNA-seq) of lung fibroblasts exposed to conditioned media from ATII cells undergoing RAS-induced EMT identified many differentially expressed genes including those involved in cell migration and extracellular matrix (ECM) regulation. We confirmed that paracrine signalling between AS-activated ATII cells and fibroblasts augmented fibroblast recruitment and demonstrated that this involved a ZEB1-tissue plasminogen activator (tPA) axis. In a reciprocal fashion, paracrine signalling from TGF-β-activated lung fibroblasts or IPF fibroblasts induced RAS activation in ATII cells, at least partially via the secreted protein, SPARC. Together these data identify that aberrant bi-directional epithelial-mesenchymal crosstalk in IPF drives a chronic feedback loop that maintains a wound-healing phenotype and provides self-sustaining pro-fibrotic signals.
Project description:Fibrosis is a condition shared by numerous inflammatory diseases. The molecular mechanisms underlying fibrosis have remained incompletely understood severely hampering drug development. CXCL4 is associated with the onset and extent of fibrosis development in systemic sclerosis (SSc), a prototypic inflammatory and fibrotic disease. Here, we integrated 65 paired sequential whole genome transcriptional and methylation profiles from monocyte-derived cells as they respond to CXCL4 exposure. Using data-driven gene regulatory network analyses, we demonstrate that CXCL4 dramatically alters monocyte differentiation trajectory inducing a novel pro-inflammatory and pro-fibrotic phenotype mediated via key regulators such as CIITA and IRF8. Importantly, these CXCL4 exposed pro-inflammatory cells trigger a fibrosis cascade by directly producing ECM molecules and by inducing myofibroblast differentiation. Underscoring the computationally identified gene regulatory network, inhibition of CIITA mimicked CXCL4 inducing pro-inflammatory and pro-fibrotic phenotype. Our study uncovers CXCL4 as the endogenous ligand driving innate immune training and forming the long-sought link between inflammation and fibrosis. Correspondence to: Prof. Timothy RDJ Radstake (T.R.D.J.Radstake@umcutrecht.nl) and Dr. Aridaman Pandit (A.Pandit@umcutrecht.nl)
Project description:Fibrosis is a condition shared by numerous inflammatory diseases. The molecular mechanisms underlying fibrosis have remained incompletely understood severely hampering drug development. CXCL4 is associated with the onset and extent of fibrosis development in systemic sclerosis (SSc), a prototypic inflammatory and fibrotic disease. Here, we integrated 65 paired sequential whole genome transcriptional and methylation profiles from monocyte-derived cells as they respond to CXCL4 exposure. Using data-driven gene regulatory network analyses, we demonstrate that CXCL4 dramatically alters monocyte differentiation trajectory inducing a novel pro-inflammatory and pro-fibrotic phenotype mediated via key regulators such as CIITA and IRF8. Importantly, these CXCL4 exposed pro-inflammatory cells trigger a fibrosis cascade by directly producing ECM molecules and by inducing myofibroblast differentiation. Underscoring the computationally identified gene regulatory network, inhibition of CIITA mimicked CXCL4 inducing pro-inflammatory and pro-fibrotic phenotype. Our study uncovers CXCL4 as the endogenous ligand driving innate immune training and forming the long-sought link between inflammation and fibrosis. Correspondence to: Prof. Timothy RDJ Radstake (T.R.D.J.Radstake@umcutrecht.nl) and Dr. Aridaman Pandit (A.Pandit@umcutrecht.nl)