scholarly journals β-cell dedifferentiation is associated with epithelial-mesenchymal transition triggered by miR-7-mediated repression of mSwi/Snf complex

2019 ◽  
Author(s):  
Tracy CS Mak ◽  
Yorrick von Ohlen ◽  
Yi Fang Wang ◽  
Eva Kane ◽  
Kaste Jurgaityte ◽  
...  
Keyword(s):  
Epithelial To Mesenchymal Transition ◽  
Epithelial Mesenchymal Transition ◽  
Tissue Injury ◽  
Β Cells ◽  
Β Cell ◽  
Cell Dedifferentiation ◽  
Mesenchymal Transition ◽  
Pathological Mechanism ◽  
Chromatin Remodeling Complexes ◽  
Pancreatic Dysfunction

Abstractβ-cell dedifferentiation has been revealed as a pathological mechanism underlying pancreatic dysfunction in diabetes. However, little is known on the genetic and epigenetic changes linked with the dedifferentiation of β-cells. We now report that β-cell dedifferentiation is associated with epithelial to mesenchymal transition (EMT) triggered by miR-7-mediated repression of Smarca4/Brg1 expression, a catalytic subunit of the mSwi/Snf chromatin remodeling complexes essential for β-cell transcription factors (β-TFs) activity. miR-7-mediated repression of Brg1 expression in diabetes causes an overall compaction of chromatin structure preventing β-TFs from accessing and transactivating genes maintaining the functional and epithelial identity of β-cells. Concomitantly, loss of β-cell identity impairs the ability of β-TFs Pdx1, Nkx6-1, Neurod1 to repress non-β-cell genes enriched selectively in mesenchymal cells leading to EMT, change in islet microenvironment, and fibrosis. Remarkably, anti-EMT agents normalized glucose tolerance of diabetic mice, thus revealing mesenchymal reprogramming of β-cells as a novel therapeutic target in diabetes. This study sheds light on the genetic signature of dedifferentiated β-cells and highlights how loss of mSwi/Snf activity in diabetes initiating a step-wise remodeling of epigenetic landscapes of β-cells leading to the induction of an EMT process reminiscent of a response to tissue injury.

scholarly journals Increased vimentin in human α- and β-cells in type 2 diabetes

2017 ◽  
Vol 233 (3) ◽  
pp. 217-227 ◽  
Author(s):  
Maaike M Roefs ◽  
Françoise Carlotti ◽  
Katherine Jones ◽  
Hannah Wills ◽  
Alexander Hamilton ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Epithelial To Mesenchymal Transition ◽  
Islet Cells ◽  
Cell Types ◽  
Β Cells ◽  
Β Cell ◽  
Mesenchymal Transition ◽  
Cell Expression

Type 2 diabetes (T2DM) is associated with pancreatic islet dysfunction. Loss of β-cell identity has been implicated via dedifferentiation or conversion to other pancreatic endocrine cell types. How these transitions contribute to the onset and progression of T2DM in vivo is unknown. The aims of this study were to determine the degree of epithelial-to-mesenchymal transition occurring in α and β cells in vivo and to relate this to diabetes-associated (patho)physiological conditions. The proportion of islet cells expressing the mesenchymal marker vimentin was determined by immunohistochemistry and quantitative morphometry in specimens of pancreas from human donors with T2DM (n = 28) and without diabetes (ND, n = 38) and in non-human primates at different stages of the diabetic syndrome: normoglycaemic (ND, n = 4), obese, hyperinsulinaemic (HI, n = 4) and hyperglycaemic (DM, n = 8). Vimentin co-localised more frequently with glucagon (α-cells) than with insulin (β-cells) in the human ND group (1.43% total α-cells, 0.98% total β-cells, median; P < 0.05); these proportions were higher in T2DM than ND (median 4.53% α-, 2.53% β-cells; P < 0.05). Vimentin-positive β-cells were not apoptotic, had reduced expression of Nkx6.1 and Pdx1, and were not associated with islet amyloidosis or with bihormonal expression (insulin + glucagon). In non-human primates, vimentin-positive β-cell proportion was larger in the diabetic than the ND group (6.85 vs 0.50%, medians respectively, P < 0.05), but was similar in ND and HI groups. In conclusion, islet cell expression of vimentin indicates a degree of plasticity and dedifferentiation with potential loss of cellular identity in diabetes. This could contribute to α- and β-cell dysfunction in T2DM.

scholarly journals Glucose homeostasis is regulated by pancreatic β-cell cilia via endosomal EphA-processing

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Francesco Volta ◽  
M. Julia Scerbo ◽  
Anett Seelig ◽  
Robert Wagner ◽  
Nils O’Brien ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Glucose Homeostasis ◽  
Basal Body ◽  
Primary Cilia ◽  
Epithelial To Mesenchymal Transition ◽  
Human Islets ◽  
Β Cells ◽  
Β Cell ◽  
Mesenchymal Transition ◽  
Glucose Levels

Abstract Diabetes mellitus affects one in eleven adults worldwide. Most suffer from Type 2 Diabetes which features elevated blood glucose levels and an inability to adequately secrete or respond to insulin. Insulin producing β-cells have primary cilia which are implicated in the regulation of glucose metabolism, insulin signaling and secretion. To better understand how β-cell cilia affect glucose handling, we ablate cilia from mature β-cells by deleting key cilia component Ift88. Here we report that glucose homeostasis and insulin secretion deteriorate over 12 weeks post-induction. Cilia/basal body components are required to suppress spontaneous auto-activation of EphA3 and hyper-phosphorylation of EphA receptors inhibits insulin secretion. In β-cells, loss of cilia/basal body function leads to polarity defects and epithelial-to-mesenchymal transition. Defective insulin secretion from IFT88-depleted human islets and elevated pEPHA3 in islets from diabetic donors both point to a role for cilia/basal body proteins in human glucose homeostasis.

scholarly journals One process for pancreatic β-cell coalescence into islets involves an epithelial–mesenchymal transition

2009 ◽  
Vol 203 (1) ◽  
pp. 19-31 ◽  
Author(s):  
Lori Cole ◽  
Miranda Anderson ◽  
Parker B Antin ◽  
Sean W Limesand
Keyword(s):  
Progenitor Cell ◽  
Epithelial Mesenchymal Transition ◽  
Transcriptional Repressors ◽  
Β Cells ◽  
Β Cell ◽  
Cell Specification ◽  
Neurogenin 3 ◽  
Mesenchymal Transition ◽  
Ductal Epithelium

Islet replacement is a promising therapy for treating diabetes mellitus, but the supply of donor tissue for transplantation is limited. To overcome this limitation, endocrine tissue can be expanded, but this requires an understanding of normal developmental processes that regulate islet formation. In this study, we compare pancreas development in sheep and human, and provide evidence that an epithelial–mesenchymal transition (EMT) is involved in β-cell differentiation and islet formation. Transcription factors know to regulate pancreas formation, pancreatic duodenal homeobox factor 1, neurogenin 3, NKX2-2, and NKX6-1, which were expressed in the appropriate spatial and temporal pattern to coordinate pancreatic bud outgrowth and direct endocrine cell specification in sheep. Immunofluorescence staining of the developing pancreas was used to co-localize insulin and epithelial proteins (cytokeratin, E-cadherin, and β-catenin) or insulin and a mesenchymal protein (vimentin). In sheep, individual β-cells become insulin-positive in the progenitor epithelium, then lose epithelial characteristics, and migrate out of the epithelial layer to form islets. As β-cells exit the epithelial progenitor cell layer, they acquire mesenchymal characteristics, shown by their acquisition of vimentin. In situ hybridization expression analysis of the SNAIL family members of transcriptional repressors (SNAIL1, -2, and -3; listed as SNAI1, -2, -3 in the HUGO Database) showed that each of the SNAIL genes was expressed in the ductal epithelium during development, and SNAIL-1 and -2 were co-expressed with insulin. Our findings provide strong evidence that the movement of β-cells from the pancreatic ductal epithelium involves an EMT.

scholarly journals Role of the ABL tyrosine kinases in the epithelial–mesenchymal transition and the metastatic cascade

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Jillian Hattaway Luttman ◽  
Ashley Colemon ◽  
Benjamin Mayro ◽  
Ann Marie Pendergast
Keyword(s):  
Solid Tumors ◽  
Tyrosine Kinases ◽  
Epithelial To Mesenchymal Transition ◽  
Kinase Inhibitors ◽  
Epithelial Mesenchymal Transition ◽  
Therapeutic Effects ◽  
Mesenchymal Transition ◽  
Metastatic Cascade ◽  
Abl Kinases ◽  
Treatment Paradigm

AbstractThe ABL kinases, ABL1 and ABL2, promote tumor progression and metastasis in various solid tumors. Recent reports have shown that ABL kinases have increased expression and/or activity in solid tumors and that ABL inactivation impairs metastasis. The therapeutic effects of ABL inactivation are due in part to ABL-dependent regulation of diverse cellular processes related to the epithelial to mesenchymal transition and subsequent steps in the metastatic cascade. ABL kinases target multiple signaling pathways required for promoting one or more steps in the metastatic cascade. These findings highlight the potential utility of specific ABL kinase inhibitors as a novel treatment paradigm for patients with advanced metastatic disease.

scholarly journals Modulation of Epithelial to Mesenchymal Transition Signaling Pathways by Olea Europaea and Its Active Compounds

2019 ◽  
Vol 20 (14) ◽  
pp. 3492 ◽  
Author(s):  
Rabiatul Adawiyah Razali ◽  
Yogeswaran Lokanathan ◽  
Muhammad Dain Yazid ◽  
Ayu Suraya Ansari ◽  
Aminuddin Bin Saim ◽  
...  
Keyword(s):  
Olea Europaea ◽  
Epithelial To Mesenchymal Transition ◽  
Epithelial Mesenchymal Transition ◽  
Healing Process ◽  
Mesenchymal Cell ◽  
Cell Phenotype ◽  
Wound Healing Process ◽  
Active Compounds ◽  
Mesenchymal Transition ◽  
Olea Europaéa

Epithelial-mesenchymal transition (EMT) is a significant dynamic process that causes changes in the phenotype of epithelial cells, changing them from their original phenotype to the mesenchymal cell phenotype. This event can be observed during wound healing process, fibrosis and cancer. EMT-related diseases are usually caused by inflammation that eventually leads to tissue remodeling in the damaged tissue. Prolonged inflammation causes long-term EMT activation that can lead to tissue fibrosis or cancer. Due to activation of EMT by its signaling pathway, therapeutic approaches that modulate that pathway should be explored. Olea europaea (OE) is well-known for its anti-inflammatory effects and abundant beneficial active compounds. These properties are presumed to modulate EMT events. This article reviews recent evidence of the effects of OE and its active compounds on EMT events and EMT-related diseases. Following evidence from the literature, it was shown that OE could modulate TGFβ/SMAD, AKT, ERK, and Wnt/β-catenin pathways in EMT due to a potent active compound that is present therein.

scholarly journals Cytoplasmic NOTCH and membrane-derived β-catenin link cell fate choice to epithelial-mesenchymal transition during myogenesis

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Daniel Sieiro ◽  
Anne C Rios ◽  
Claire E Hirst ◽  
Christophe Marcelle
Keyword(s):  
Cell Fate ◽  
Epithelial To Mesenchymal Transition ◽  
Epithelial Mesenchymal Transition ◽  
Mesenchymal Transition ◽  
Epithelial Plasticity ◽  
Cellular Environment ◽  
Muscle Formation ◽  
Fate Decision ◽  
Gsk 3Β ◽  
Coupling Cell

How cells in the embryo coordinate epithelial plasticity with cell fate decision in a fast changing cellular environment is largely unknown. In chick embryos, skeletal muscle formation is initiated by migrating Delta1-expressing neural crest cells that trigger NOTCH signaling and myogenesis in selected epithelial somite progenitor cells, which rapidly translocate into the nascent muscle to differentiate. Here, we uncovered at the heart of this response a signaling module encompassing NOTCH, GSK-3β, SNAI1 and β-catenin. Independent of its transcriptional function, NOTCH profoundly inhibits GSK-3β activity. As a result SNAI1 is stabilized, triggering an epithelial to mesenchymal transition. This allows the recruitment of β-catenin from the membrane, which acts as a transcriptional co-factor to activate myogenesis, independently of WNT ligand. Our results intimately associate the initiation of myogenesis to a change in cell adhesion and may reveal a general principle for coupling cell fate changes to EMT in many developmental and pathological processes.

Glaucoma following Infant Lensectomy: 2021 Update

2021 ◽  
Author(s):  
David S. Walton ◽  
Helen H. Yeung
Keyword(s):  
Anterior Chamber ◽  
Clinical Evidence ◽  
Epithelial Mesenchymal Transition ◽  
Tissue Injury ◽  
Loss Of Function ◽  
Mesenchymal Transition ◽  
Responsible Mechanism ◽  
Cell Dispersion ◽  
Aphakic Glaucoma ◽  
Lens Cell

Abstract Purpose To review information pertaining to glaucoma following infant lensectomy surgery and to provide evidence to support the responsible mechanism of this condition. Methods and Results Described risk factors and proposed mechanisms for infantile aphakic glaucoma were assessed. The clinical evidence observed in affected glaucoma patients was analyzed, and evidence of postoperative anterior chamber fibrosis was reviewed and interpreted. Conclusion The review and assessment of laboratory and clinical evidence support the proposal that infantile aphakic glaucoma is caused, in part, by postoperative anterior chamber fibroization related to lens cell dispersion and active epithelial-mesenchymal transition with resultant filtration angle tissue injury and loss of function.

The Role of Calcium Signaling in Regulation of Epithelial-Mesenchymal Transition

2020 ◽  
pp. 1-23
Author(s):  
Divya Adiga ◽  
Raghu Radhakrishnan ◽  
Sanjiban Chakrabarty ◽  
Prashant Kumar ◽  
Shama Prasada Kabekkodu
Keyword(s):  
Cancer Metastasis ◽  
Epithelial To Mesenchymal Transition ◽  
Epithelial Mesenchymal Transition ◽  
Critical Role ◽  
Cancer Therapeutics ◽  
Growth And Survival ◽  
Mesenchymal Transition ◽  
Microenvironmental Factors ◽  
Favorable Clinical Outcome

Despite substantial advances in the field of cancer therapeutics, metastasis is a significant challenge for a favorable clinical outcome. Epithelial to mesenchymal transition (EMT) is a process of acquiring increased motility, invasiveness, and therapeutic resistance by cancer cells for their sustained growth and survival. A plethora of intrinsic mechanisms and extrinsic microenvironmental factors drive the process of cancer metastasis. Calcium (Ca<sup>2+</sup>) signaling plays a critical role in dictating the adaptive metastatic cell behavior comprising of cell migration, invasion, angiogenesis, and intravasation. By modulating EMT, Ca<sup>2+</sup> signaling can regulate the complexity and dynamics of events leading to metastasis. This review summarizes the role of Ca<sup>2+</sup> signal remodeling in the regulation of EMT and metastasis in cancer.

scholarly journals CD47-SIRPα Signaling Induces Epithelial-Mesenchymal Transition and Cancer Stemness and Links to a Poor Prognosis in Patients with Oral Squamous Cell Carcinoma

Cells ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1658 ◽  
Author(s):  
Shin Pai ◽  
Oluwaseun Adebayo Bamodu ◽  
Yen-Kuang Lin ◽  
Chun-Shu Lin ◽  
Pei-Yi Chu ◽  
...  
Keyword(s):  
Squamous Cell Carcinoma ◽  
Transcription Factor ◽  
Oral Squamous Cell Carcinoma ◽  
Cell Carcinoma ◽  
Squamous Cell ◽  
Epithelial To Mesenchymal Transition ◽  
Epithelial Mesenchymal Transition ◽  
Therapy Resistance ◽  
Cellular Migration ◽  
Mesenchymal Transition

Background: Oral squamous cell carcinoma (OSCC), with high mortality rates, is one of the most diagnosed head and neck cancers. Epithelial-to-mesenchymal transition (EMT) and the generation of cancer stem cells (CSCs) are two keys for therapy-resistance, relapse, and distant metastasis. Accumulating evidence indicates that aberrantly expressed cluster of differentiation (CD)47 is associated with cell-death evasion and metastasis; however, the role of CD47 in the generation of CSCs in OSCC is not clear. Methods: We investigated the functional roles of CD47 in OSCC cell lines SAS, TW2.6, HSC-3, and FaDu using the bioinformatics approach, immunoblotting, immunofluorescence staining, and assays for cellular migration, invasion, colony, and orosphere formation, as well as radiosensitivity. Results: We demonstrated increased expression of CD47 in OSCC patients was associated with an estimated poorly survival disadvantage (p = 0.0391) and positively correlated with the expression of pluripotency factors. Silencing CD47 significantly suppressed cell viability and orosphere formation, accompanied by a downregulated expression of CD133, SRY-Box transcription factor 2 (SOX2), octamer-binding transcription factor 4 (OCT4), and c-Myc. In addition, CD47-silenced OSCC cells showed reduced EMT, migration, and clonogenicity reflected by increased E-cadherin and decreased vimentin, Slug, Snail, and N-cadherin expression. Conclusion: Of therapeutic relevance, CD47 knockdown enhanced the anti-OSCC effect of radiotherapy. Collectively, we showed an increased CD47 expression promoted the generation of CSCs and malignant OSCC phenotypes. Silencing CD47, in combination with radiation, could provide an alternative and improved therapeutic efficacy for OSCC patients.

scholarly journals Roles of MicroRNA-34a in Epithelial to Mesenchymal Transition, Competing Endogenous RNA Sponging and Its Therapeutic Potential

2019 ◽  
Vol 20 (4) ◽  
pp. 861 ◽  
Author(s):  
Dongsong Nie ◽  
Jiewen Fu ◽  
Hanchun Chen ◽  
Jingliang Cheng ◽  
Junjiang Fu
Keyword(s):  
Cancer Therapy ◽  
Cancer Progression ◽  
Noncoding Rna ◽  
Epithelial To Mesenchymal Transition ◽  
Epithelial Mesenchymal Transition ◽  
Therapeutic Potential ◽  
Circular Rna ◽  
Signal Pathways ◽  
Competing Endogenous Rna ◽  
Mesenchymal Transition

MicroRNA-34a (miR-34a), a tumor suppressor, has been reported to be dysregulated in various human cancers. MiR-34a is involves in certain epithelial-mesenchymal transition (EMT)-associated signal pathways to repress tumorigenesis, cancer progression, and metastasis. Due to the particularity of miR-34 family in tumor-associated EMT, the significance of miR-34a is being increasingly recognized. Competing endogenous RNA (ceRNA) is a novel concept involving mRNA, circular RNA, pseudogene transcript, and long noncoding RNA regulating each other’s expressions using microRNA response elements to compete for the binding of microRNAs. Studies showed that miR-34a is efficient for cancer therapy. Here, we provide an overview of the function of miR-34a in tumor-associated EMT. ceRNA hypothesis plays an important role in miR-34a regulation in EMT, cancer progression, and metastasis. Its potential roles and challenges as a microRNA therapeutic candidate are discussed. As the negative effect on cancer progression, miR-34a should play crucial roles in clinical diagnosis and cancer therapy.

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