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Scientific Reports Jun 2024To explore the molecular pathogenesis of pulmonary arterial hypertension (PAH) and identify potential therapeutic targets, we performed transcriptome sequencing of lung...
To explore the molecular pathogenesis of pulmonary arterial hypertension (PAH) and identify potential therapeutic targets, we performed transcriptome sequencing of lung tissue from mice with hypoxia-induced pulmonary hypertension. Our Gene Ontology analysis revealed that "extracellular matrix organization" ranked high in the biological process category, and matrix metallopeptidases (MMPs) and other proteases also played important roles in it. Moreover, compared with those in the normoxia group, we confirmed that MMPs expression was upregulated in the hypoxia group, while the hub gene Timp1 was downregulated. Crocin, a natural MMP inhibitor, was found to reduce inflammation, decrease MMPs levels, increase Timp1 expression levels, and attenuate hypoxia-induced pulmonary hypertension in mice. In addition, analysis of the cell distribution of MMPs and Timp1 in the human lung cell atlas using single-cell RNAseq datasets revealed that MMPs and Timp1 are mainly expressed in a population of fibroblasts. Moreover, in vitro experiments revealed that crocin significantly inhibited myofibroblast proliferation, migration, and extracellular matrix deposition. Furthermore, we demonstrated that crocin inhibited TGF-β1-induced fibroblast activation and regulated the pulmonary arterial fibroblast MMP2/TIMP1 balance by inhibiting the TGF-β1/Smad3 signaling pathway. In summary, our results indicate that crocin attenuates hypoxia-induced pulmonary hypertension in mice by inhibiting TGF-β1-induced myofibroblast activation.
Topics: Animals; Tissue Inhibitor of Metalloproteinase-1; Mice; Hypoxia; Hypertension, Pulmonary; Carotenoids; Humans; Matrix Metalloproteinase 2; Male; Signal Transduction; Transforming Growth Factor beta1; Disease Models, Animal; Cell Proliferation; Mice, Inbred C57BL; Smad3 Protein; Cell Movement; Lung
PubMed: 38830933
DOI: 10.1038/s41598-024-62900-8 -
Cell Death & Disease Jun 2024Tissue injury causes activation of mesenchymal lineage cells into wound-repairing myofibroblasts (MFs), whose uncontrolled activity ultimately leads to fibrosis....
Tissue injury causes activation of mesenchymal lineage cells into wound-repairing myofibroblasts (MFs), whose uncontrolled activity ultimately leads to fibrosis. Although this process is triggered by deep metabolic and transcriptional reprogramming, functional links between these two key events are not yet understood. Here, we report that the metabolic sensor post-translational modification O-linked β-D-N-acetylglucosaminylation (O-GlcNAcylation) is increased and required for myofibroblastic activation. Inhibition of protein O-GlcNAcylation impairs archetypal myofibloblast cellular activities including extracellular matrix gene expression and collagen secretion/deposition as defined in vitro and using ex vivo and in vivo murine liver injury models. Mechanistically, a multi-omics approach combining proteomic, epigenomic, and transcriptomic data mining revealed that O-GlcNAcylation controls the MF transcriptional program by targeting the transcription factors Basonuclin 2 (BNC2) and TEA domain transcription factor 4 (TEAD4) together with the Yes-associated protein 1 (YAP1) co-activator. Indeed, inhibition of protein O-GlcNAcylation impedes their stability leading to decreased functionality of the BNC2/TEAD4/YAP1 complex towards promoting activation of the MF transcriptional regulatory landscape. We found that this involves O-GlcNAcylation of BNC2 at Thr and Ser and of TEAD4 at Ser and Ser. Altogether, this study unravels protein O-GlcNAcylation as a key determinant of myofibroblastic activation and identifies its inhibition as an avenue to intervene with fibrogenic processes.
Topics: Myofibroblasts; Animals; Mice; Signal Transduction; Humans; Fibrosis; Transcription Factors; YAP-Signaling Proteins; Mice, Inbred C57BL; TEA Domain Transcription Factors; Male; Protein Processing, Post-Translational; Acetylglucosamine; Transcription, Genetic; Adaptor Proteins, Signal Transducing
PubMed: 38830870
DOI: 10.1038/s41419-024-06773-9 -
Urology Case Reports May 2024We present the case of a patient with X-Linked Hypophosphatemia (XLH) and an inflammatory myofibroblastic tumor (IMT) of the bladder which prompted further investigation...
We present the case of a patient with X-Linked Hypophosphatemia (XLH) and an inflammatory myofibroblastic tumor (IMT) of the bladder which prompted further investigation into the possible relationship between XLH and IMT i.e. a case of Occam's Razor or Hickam's Dictum?
PubMed: 38827529
DOI: 10.1016/j.eucr.2024.102710 -
BioRxiv : the Preprint Server For... May 2024Fibrosis drives end-organ damage in many diseases. However, clinical trials targeting individual upstream activators of fibroblasts, such as TGFβ, have largely failed....
UNLABELLED
Fibrosis drives end-organ damage in many diseases. However, clinical trials targeting individual upstream activators of fibroblasts, such as TGFβ, have largely failed. Here, we target the leukemia inhibitory factor receptor (LIFR) as a "master amplifier" of multiple upstream activators of lung fibroblasts. In idiopathic pulmonary fibrosis (IPF), the most common fibrotic lung disease, we found that lung myofibroblasts had high LIF expression. Further, TGFβ1, one of the key drivers of fibrosis, upregulated LIF expression in IPF fibroblasts. In vitro anti-LIFR antibody blocking on human IPF lung fibroblasts reduced induction of profibrotic genes downstream of TGFβ1, IL-4 and IL-13. Further, siRNA silencing of LIFR in IPF precision cut lung slices reduced expression of fibrotic proteins. Together, we find that LIFR drives an autocrine positive feedback loop that amplifies and sustains pathogenic activation of IPF fibroblasts downstream of multiple external stimuli, implicating LIFR as a therapeutic target in fibrosis.
SIGNIFICANCE STATEMENT
Fibroblasts have a central role in the pathogenesis of fibrotic diseases. However, due to in part to multiple profibrotic stimuli, targeting a single activator of fibroblasts, like TGFβ, has not yielded successful clinical treatments. We hypothesized that a more effective therapeutic strategy is identifying a downstream "master amplifier" of a range of upstream profibrotic stimuli. This study identifies the leukemia inhibitory factor receptor (LIFR) on fibrotic lung fibroblasts amplifies multiple profibrotic stimuli, such as IL-13 and TGFβ. Blocking LIFR reduced fibrosis in ex vivo lung tissue from patients with idiopathic pulmonary fibrosis (IPF). LIFR, acting as a master amplifier downstream of fibroblast activation, offers an alternative therapeutic strategy for fibrotic diseases.
PubMed: 38826450
DOI: 10.1101/2024.05.21.595153 -
Journal of Orthopaedic Surgery and... Jun 2024Fibrosis is a significant pathological feature of chronic skeletal muscle injury, profoundly affecting muscle regeneration. Fibro-adipogenic progenitors (FAPs) have the...
BACKGROUND
Fibrosis is a significant pathological feature of chronic skeletal muscle injury, profoundly affecting muscle regeneration. Fibro-adipogenic progenitors (FAPs) have the ability to differentiate into myofibroblasts, acting as a primary source of extracellular matrix (ECM). the process by which FAPs differentiate into myofibroblasts during chronic skeletal muscle injury remains inadequately explored.
METHOD
mouse model with sciatic nerve denervated was constructed and miRNA expression profiles between the mouse model and uninjured mouse were analyzed. qRT/PCR and immunofluorescence elucidated the effect of miR-27b-3p on fibrosis in vivo and in vitro. Dual-luciferase reporter identified the target gene of miR-27b-3p, and finally knocked down or overexpressed the target gene and phosphorylation inhibition of Smad verified the influence of downstream molecules on the abundance of miR-27b-3p and fibrogenic differentiation of FAPs.
RESULT
FAPs derived from a mouse model with sciatic nerves denervated exhibited a progressively worsening fibrotic phenotype over time. Introducing agomiR-27b-3p effectively suppressed fibrosis both in vitro and in vivo. MiR-27b-3p targeted Transforming Growth Factor Beta Receptor 1 (TGF-βR1) and the abundance of miR-27b-3p was negatively regulated by TGF-βR1/Smad.
CONCLUSION
miR-27b-3p targeting the TGF-βR1/Smad pathway is a novel mechanism for regulating fibrogenic differentiation of FAPs. Increasing abundance of miR-27b-3p, suppressing expression of TGF-βR1 and inhibiting phosphorylation of smad3 presented potential strategies for treating fibrosis in chronic skeletal muscle injury.
Topics: Animals; MicroRNAs; Fibrosis; Muscle, Skeletal; Mice; Signal Transduction; Chronic Disease; Receptor, Transforming Growth Factor-beta Type I; Mice, Inbred C57BL; Smad Proteins; Male; Disease Models, Animal; Cell Differentiation; Sciatic Nerve
PubMed: 38825706
DOI: 10.1186/s13018-024-04733-9 -
Iranian Journal of Allergy, Asthma, and... Apr 2024Systemic sclerosis (SSc) is an autoimmune systemic disease that is characterized by immune dysregulation, inflammation, vasculopathy, and fibrosis. Tissue fibrosis plays...
Systemic sclerosis (SSc) is an autoimmune systemic disease that is characterized by immune dysregulation, inflammation, vasculopathy, and fibrosis. Tissue fibrosis plays an important role in SSc and can affect several organs such as the dermis, lungs, and heart. Dysregulation of interferon (IFN) signaling contributes to the SSc pathogenesis and interferon regulatory factor 1 (IRF1) has been indicated as the main regulator of type I IFN. This study aimed to clarify the effect of IFN-gamma (-γ) and dexamethasone (DEX) on the IRF1, extracellular signal-regulated kinase 1/2 (ERK1/2), and the expression of alpha-smooth muscle actin (α-SMA) in myofibroblasts and genes involved in the inflammation and fibrosis processes in early diffuse cutaneous systemic sclerosis (dcSSc). A total of 10 early dcSSc patients (diffuse cutaneous form) and 10 unaffected control dermis biopsies were obtained to determine IFNγ and DEX effects on inflammation and fibrosis. Fibroblasts were treated with IFNγ and DEX at optimum time and dose. The expression level of genes and proteins involved in the fibrosis and inflammation processes have been quantified by quantitative real-time PCR (RT-qPCR) and western blot, respectively. IFNγ could up-regulate some of the inflammation-related genes (Interleukin-6; IL6) and down-regulate some of the fibrosis-related genes (COL1A1) in cultured fibroblasts of patients with early dcSSc compared to the untreated group. Besides, it has been revealed that IFNγ can induce fibroblast differentiation to the myofibroblast that expresses α-SMA. Concerning the inhibitory effect of IFNγ on some fibrotic genes and its positive effect on the inflammatory genes and myofibroblast differentiation, it seems that IFNγ may play a dual role in SSc.
Topics: Adult; Female; Humans; Male; Middle Aged; Actins; Cells, Cultured; Dexamethasone; Fibroblasts; Fibrosis; Gene Expression Regulation; Interferon Regulatory Factor-1; Interferon-gamma; Interleukin-6; Myofibroblasts; Scleroderma, Systemic
PubMed: 38822514
DOI: 10.18502/ijaai.v23i2.15325 -
Cancer Letters Jul 2024Cancer-associated fibroblasts play a crucial role within the tumor microenvironment. However, a comprehensive characterization of CAF in colorectal cancer (CRC) is still...
Cancer-associated fibroblasts play a crucial role within the tumor microenvironment. However, a comprehensive characterization of CAF in colorectal cancer (CRC) is still missing. We combined scRNA-seq and spatial proteomics to decipher fibroblast heterogeneity in healthy human colon and CRC at high resolution. Analyzing nearly 23,000 fibroblasts, we identified 11 distinct clusters and verified them by spatial proteomics. Four clusters, consisting of myofibroblastic CAF (myCAF)-like, inflammatory CAF (iCAF)-like and proliferating fibroblasts as well as a novel cluster, which we named "T cell-inhibiting CAF" (TinCAF), were primarily found in CRC. This new cluster was characterized by the expression of immune-interacting receptors and ligands, including CD40 and NECTIN2. Co-culture of CAF and T cells resulted in a reduction of the effector T cell compartment, impaired proliferation, and increased exhaustion. By blocking its receptor interaction, we demonstrated that NECTIN2 was the key driver of T cell inhibition. Analysis of clinical datasets showed that NECTIN2 expression is a poor prognostic factor in CRC and other tumors. In conclusion, we identified a new class of immuno-suppressive CAF with features rendering them a potential target for future immunotherapies.
Topics: Humans; Colorectal Neoplasms; Nectins; Cancer-Associated Fibroblasts; Signal Transduction; Tumor Microenvironment; T-Lymphocytes; Cell Proliferation; Coculture Techniques; Proteomics
PubMed: 38821255
DOI: 10.1016/j.canlet.2024.216985 -
Biomedicine & Pharmacotherapy =... Jul 2024Considering the limited efficacy of current therapies in lung, colorectal, and pancreatic cancers, innovative combination treatments with diverse mechanisms of action...
Considering the limited efficacy of current therapies in lung, colorectal, and pancreatic cancers, innovative combination treatments with diverse mechanisms of action are needed to improve patients' outcomes. Chitinase-3 like-1 protein (CHI3L1) emerges as a versatile factor with significant implications in various diseases, particularly cancers, fostering an immunosuppressive tumor microenvironment for cancer progression. Therefore, pre-clinical validation is imperative to fully realize its potential in cancer treatment. We developed phage display-derived fully human monoclonal CHI3L1 neutralizing antibodies (nAbs) and verified the nAbs-antigen binding affinity and specificity in lung, pancreatic and colorectal cancer cell lines. Tumor growth signals, proliferation and migration ability were all reduced by CHI3L1 nAbs in vitro. Orthotopic or subcutaneous tumor mice model and humanized mouse model were established for characterizing the anti-tumor properties of two CHI3L1 nAb leads. Importantly, CHI3L1 nAbs not only inhibited tumor growth but also mitigated fibrosis, angiogenesis, and restored immunostimulatory functions of immune cells in pancreatic, lung, and colorectal tumor mice models. Mechanistically, CHI3L1 nAbs directly suppressed the activation of pancreatic stellate cells and the transformation of macrophages into myofibroblasts, thereby attenuating fibrosis. These findings strongly support the therapeutic potential of CHI3L1 nAbs in overcoming clinical challenges, including the failure of gemcitabine in pancreatic cancer.
Topics: Animals; Chitinase-3-Like Protein 1; Humans; Colorectal Neoplasms; Pancreatic Neoplasms; Neovascularization, Pathologic; Mice; Cell Line, Tumor; Lung Neoplasms; Cell Proliferation; Fibrosis; Antibodies, Monoclonal; Tumor Microenvironment; Xenograft Model Antitumor Assays; Antibodies, Neutralizing; Antineoplastic Agents, Immunological; Angiogenesis
PubMed: 38820971
DOI: 10.1016/j.biopha.2024.116825 -
Neural Regeneration Research Feb 2025Subretinal fibrosis is the end-stage sequelae of neovascular age-related macular degeneration. It causes local damage to photoreceptors, retinal pigment epithelium, and...
Subretinal fibrosis is the end-stage sequelae of neovascular age-related macular degeneration. It causes local damage to photoreceptors, retinal pigment epithelium, and choroidal vessels, which leads to permanent central vision loss of patients with neovascular age-related macular degeneration. The pathogenesis of subretinal fibrosis is complex, and the underlying mechanisms are largely unknown. Therefore, there are no effective treatment options. A thorough understanding of the pathogenesis of subretinal fibrosis and its related mechanisms is important to elucidate its complications and explore potential treatments. The current article reviews several aspects of subretinal fibrosis, including the current understanding on the relationship between neovascular age-related macular degeneration and subretinal fibrosis; multimodal imaging techniques for subretinal fibrosis; animal models for studying subretinal fibrosis; cellular and non-cellular constituents of subretinal fibrosis; pathophysiological mechanisms involved in subretinal fibrosis, such as aging, infiltration of macrophages, different sources of mesenchymal transition to myofibroblast, and activation of complement system and immune cells; and several key molecules and signaling pathways participating in the pathogenesis of subretinal fibrosis, such as vascular endothelial growth factor, connective tissue growth factor, fibroblast growth factor 2, platelet-derived growth factor and platelet-derived growth factor receptor-β, transforming growth factor-β signaling pathway, Wnt signaling pathway, and the axis of heat shock protein 70-Toll-like receptors 2/4-interleukin-10. This review will improve the understanding of the pathogenesis of subretinal fibrosis, allow the discovery of molecular targets, and explore potential treatments for the management of subretinal fibrosis.
PubMed: 38819041
DOI: 10.4103/NRR.NRR-D-23-01642 -
Archives of Pathology & Laboratory... May 2024Intraoperative (frozen section) analysis of lung lesions (nodules, masses, ground-glass opacities) can occasionally be diagnostically challenging.
CONTEXT.—
Intraoperative (frozen section) analysis of lung lesions (nodules, masses, ground-glass opacities) can occasionally be diagnostically challenging.
OBJECTIVE.—
To describe selected pitfalls in thoracic frozen sections with a focus on the differential diagnosis between adenocarcinoma and its mimics, and to provide tips to prevent misinterpretation.
DATA SOURCES.—
Peer-reviewed literature and the author's experience.
CONCLUSIONS.—
A common challenge in thoracic frozen sections is the differential diagnosis between lung adenocarcinoma and its mimics. Diagnostic difficulties arise because mimics of adenocarcinoma often entrap reactive lung epithelium that can appear atypical on frozen section slides. Entities that can be misinterpreted as adenocarcinoma include ciliated muconodular papillary tumor/bronchiolar adenoma, hamartoma, inflammatory myofibroblastic tumor, and pulmonary Langerhans cell histiocytosis. Knowledge of the key clinical, radiologic, and histologic features of these entities can help prevent overdiagnosis of adenocarcinoma. Pathologic findings that facilitate the distinction between adenocarcinoma and its mimics at frozen section include the appearance and contour of the lesion at low magnification, growth patterns, cilia, stromal features, shape of the epithelial cells (cuboidal versus columnar), nuclear features of malignancy (crowding, hyperchromasia, irregular contours), and abruptness of the junction between the lesion and adjacent uninvolved lung. Knowledge of the clinical context, imaging findings, and the surgical consequence of the intraoperative diagnosis can also prevent diagnostic errors. Finally, since adenocarcinomas of the lung are often relatively bland and lack the stromal desmoplasia seen in adenocarcinomas of other organs, familiarity with the morphologic spectrum of lung adenocarcinomas at frozen section analysis is important.
PubMed: 38818706
DOI: 10.5858/arpa.2024-0023-RA