Publications by authors named "Ormiston M"

Article Synopsis
  • - Drp1, a protein involved in mitochondrial fission, contributes to the increase in pulmonary artery smooth muscle cells in pulmonary arterial hypertension (PAH), and researchers developed a new inhibitor called Drpitor1a to test its effectiveness.
  • - Experiments showed that Drpitor1a successfully inhibited Drp1 activity, reduced cell proliferation and increased apoptosis in PAH cells, while not affecting normal cells or causing toxicity.
  • - The findings suggest that Drpitor1a could be a viable treatment for PAH by targeting Drp1, with notable differences in effectiveness observed between male and female subjects.
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The tumour evolution model posits that malignant transformation is preceded by randomly distributed driver mutations in cancer genes, which cause clonal expansions in phenotypically normal tissues. Although clonal expansions can remodel entire tissues, the mechanisms that result in only a small number of clones transforming into malignant tumours remain unknown. Here we develop an in vivo single-cell CRISPR strategy to systematically investigate tissue-wide clonal dynamics of the 150 most frequently mutated squamous cell carcinoma genes.

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Natural killer (NK) cell phenotype and function are altered in patients with prostate cancer, and increased NK cell activity is associated with a better prognosis in patients with disease. For patients with advanced stage prostate cancer, immunotherapies are a promising approach when standard treatment options have been exhausted. With the rapid emergence of NK cell-based therapies, it is important to understand the mechanisms by which NK cells can be triggered to kill cancer cells that have developed immune-evasive strategies.

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Natural killer (NK) cells are cytotoxic group 1 innate lymphoid cells (ILC), known for their role as killers of stressed, cancerous, and virally infected cells. Beyond this cytotoxic function, NK cell subsets can influence broader immune responses through cytokine production and have been linked to central roles in non-immune processes, such as the regulation of vascular remodeling in pregnancy and cancer. Attempts to exploit the anti-tumor functions of NK cells have driven the development of various NK cell-based therapies, which have shown promise in both pre-clinical disease models and early clinical trials.

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Transcriptional and translational control are key determinants of gene expression, however, to what extent these two processes can be collectively coordinated is still poorly understood. Here, we use Nanopore long-read sequencing and cap analysis of gene expression (CAGE-seq) to document the landscape of 5' and 3' untranslated region (UTR) isoforms and transcription start sites of epidermal stem cells, wild-type keratinocytes and squamous cell carcinomas. Focusing on squamous cell carcinomas, we show that a small cohort of genes with alternative 5'UTR isoforms exhibit overall increased translational efficiencies and are enriched in ribosomal proteins and splicing factors.

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Background: Natural killer (NK) cell impairment is a feature of pulmonary arterial hypertension (PAH) and contributes to vascular remodeling in animal models of disease. Although mutations in , the gene encoding the BMP (bone morphogenetic protein) type-II receptor, are strongly associated with PAH, the contribution of loss to NK cell impairment remains unknown. We explored the impairment of IL (interleukin)-15 signaling, a central mediator of NK cell homeostasis, as both a downstream target of loss and a contributor to the pathogenesis of PAH.

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Pulmonary arterial hypertension (PAH) is a deadly disease, characterized by increased vascular resistance, pulmonary arteriolar loss, and occlusive arterial remodeling, leading to eventual right heart failure. Evidence increasingly points to the pulmonary endothelium as a central actor in PAH. Endothelial cell apoptosis can result directly in distal lung arteriolar pruning and indirectly in the formation of complex and occlusive arterial lesions, reflecting an imbalance between endothelial injury and repair in the development and progression of PAH.

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Breast cancer is the most common cancer affecting women and is the second leading cause of cancer related death worldwide. Angiogenesis, the process of new blood vessel development from pre-existing vasculature, has been implicated in the growth, progression, and metastasis of cancer. Tumor angiogenesis has been explored as a key therapeutic target for decades, as the blockade of this process holds the potential to reduce the oxygen and nutrient supplies that are required for tumor growth.

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Objective: Pulmonary arterial hypertension is a disease of proliferative vascular occlusion that is strongly linked to mutations in -the gene encoding the BMPR-II (BMP [bone morphogenetic protein] type II receptor). The endothelial-selective BMPR-II ligand, BMP9, reverses disease in animal models of pulmonary arterial hypertension and suppresses the proliferation of healthy endothelial cells. However, the impact of loss on the antiproliferative actions of BMP9 has yet to be assessed.

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Circulating natural killer (NK) cells have been shown to adopt a type 1 innate lymphoid cell (ILC1)-like phenotype in response to TGF-β and secrete VEGF-A when exposed to hypoxia. Although these changes are often considered to be linked attributes of tissue residency, it has yet to be determined if TGF-β and hypoxia work in concert to coordinate NK cellular phenotype and angiogenic potential. Examination of human circulating NK cells treated with TGF-β demonstrated heterogeneity in their potential to adopt an ILC1-like phenotype, as indicated by the upregulation of CD9 and CD103 on only a subset of cells in culture.

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Circulating NK cells are known to convert to a type 1 innate lymphoid cell (ILC1)-like phenotype in response to TGF-β exposure. However, the precise cellular changes defining this process as well as the downstream signaling pathways guiding it remain poorly defined, particularly in humans. We used mass cytometry by time-of-flight (CyTOF) to model this phenotypic shift in vitro and identify a synergistic activity of TGF-β and IL-15 in this cellular conversion.

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Article Synopsis
  • Recent research indicates that protein kinase A (PKA) inhibits angiogenic sprouting in endothelial cells, while exchange protein activated by cAMP (EPAC) does not contribute to this effect.
  • The study found that inhibiting phosphodiesterase 3 (PDE3) reduces angiogenic sprouting, showing PDE3B plays a crucial role in this process, unlike other PDEs.
  • The anti-angiogenic effects of PDE3B and PKA are linked through their regulation of cdc42 activity, and they interact closely within the cell, indicating that PDE3B limits PKA's inhibitory impact on sprouting in endothelial cells.
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Introduction: Skeletal muscle dysfunction is a clinically important complication of pulmonary arterial hypertension (PAH). Growth/differentiation factor 15 (GDF-15), a prognostic marker in PAH, has been associated with muscle loss in other conditions. We aimed to define the associations of GDF-15 and muscle wasting in PAH, to assess its utility as a biomarker of muscle loss and to investigate its downstream signalling pathway as a therapeutic target.

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Natural killer (NK) cells are cytotoxic innate lymphoid cells with an established role in the regulation of vascular structure in pregnancy and cancer. Impaired NK cell function has been identified in patients with pulmonary arterial hypertension (PAH), a disease of obstructive vascular remodeling in the lungs, as well as in multiple rodent models of disease. However, the precise contribution of NK cell impairment to the initiation and progression of PAH remains unknown.

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Pulmonary arterial hypertension (PAH) is characterized by increased proliferation and resistance to apoptosis of pulmonary vascular cells. Increased expression of translationally controlled tumor protein (TCTP), a prosurvival and antiapoptotic mediator, has recently been demonstrated in patients with heritable PAH; however, its role in the pathobiology of PAH remains unclear. Silencing of TCTP in blood outgrowth endothelial cells (BOECs) isolated from control subjects led to significant changes in morphology, cytoskeletal organization, increased apoptosis, and decreased directionality during migration.

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Pulmonary hypertension is defined as a resting mean pulmonary artery pressure of 25 mm Hg or above. This review deals with pulmonary arterial hypertension (PAH), a type of pulmonary hypertension that primarily affects the pulmonary vasculature. In PAH, the pulmonary vasculature is dynamically obstructed by vasoconstriction, structurally obstructed by adverse vascular remodeling, and pathologically non-compliant as a result of vascular fibrosis and stiffening.

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Background: Mitotic fission is increased in pulmonary arterial hypertension (PAH), a hyperproliferative, apoptosis-resistant disease. The fission mediator dynamin-related protein 1 (Drp1) must complex with adaptor proteins to cause fission. Drp1-induced fission has been therapeutically targeted in experimental PAH.

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Systemic hypertension, preeclampsia, and pulmonary arterial hypertension (PAH) are diseases of high blood pressure in the systemic or pulmonary circulation. Beyond the well-defined contribution of more traditional pathophysiological mechanisms, such as changes in the renin-angiotensin-aldosterone system, to the development of these hypertensive disorders, there is substantial clinical evidence supporting an important role for inflammation and immunity in the pathogenesis of each of these three conditions. Over the last decade, work in small animal models, bearing targeted deficiencies in specific cytokines or immune cell subsets, has begun to clarify the immune-mediated mechanisms that drive changes in vascular structure and tone in hypertensive disease.

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Background: Pulmonary arterial hypertension (PAH) is characterized by abnormal growth and enhanced glycolysis of pulmonary artery endothelial cells. However, the mechanisms underlying alterations in energy production have not been identified.

Methods: Here, we examined the miRNA and proteomic profiles of blood outgrowth endothelial cells (BOECs) from patients with heritable PAH caused by mutations in the bone morphogenetic protein receptor type 2 () gene and patients with idiopathic PAH to determine mechanisms underlying abnormal endothelial glycolysis.

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