scholarly journals Insights into Bone Morphogenetic Protein—(BMP-) Signaling in Ocular Lens Biology and Pathology

Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2604
Author(s):  
Daisy Y. Shu ◽  
Frank J. Lovicu
Keyword(s):  
Cell Fate ◽  
Bone Morphogenetic Proteins ◽  
Transforming Growth Factor Beta ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
Bmp Signaling ◽  
The Body ◽  
Ocular Lens ◽  
Mesenchymal Transition

Bone morphogenetic proteins (BMPs) are a diverse class of growth factors that belong to the transforming growth factor-beta (TGFβ) superfamily. Although originally discovered to possess osteogenic properties, BMPs have since been identified as critical regulators of many biological processes, including cell-fate determination, cell proliferation, differentiation and morphogenesis, throughout the body. In the ocular lens, BMPs are important in orchestrating fundamental developmental processes such as induction of lens morphogenesis, and specialized differentiation of its fiber cells. Moreover, BMPs have been reported to facilitate regeneration of the lens, as well as abrogate pathological processes such as TGFβ-induced epithelial-mesenchymal transition (EMT) and apoptosis. In this review, we summarize recent insights in this topic and discuss the complexities of BMP-signaling including the role of individual BMP ligands, receptors, extracellular antagonists and cross-talk between canonical and non-canonical BMP-signaling cascades in the lens. By understanding the molecular mechanisms underlying BMP activity, we can advance their potential therapeutic role in cataract prevention and lens regeneration.

scholarly journals Id2 and Id3 Define the Potency of Cell Proliferation and Differentiation Responses to Transforming Growth Factor β and Bone Morphogenetic Protein

2004 ◽  
Vol 24 (10) ◽  
pp. 4241-4254 ◽  
Author(s):  
Marcin Kowanetz ◽  
Ulrich Valcourt ◽  
Rosita Bergström ◽  
Carl-Henrik Heldin ◽  
Aristidis Moustakas
Keyword(s):  
Epithelial Cells ◽  
Growth Inhibition ◽  
Cell Fate ◽  
Bone Morphogenetic Proteins ◽  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
Transforming Growth Factor Β ◽  
Mesenchymal Transition ◽  
Cell Proliferation And Differentiation ◽  
Morphogenetic Protein

ABSTRACT Transforming growth factors β (TGF-βs) inhibit growth of epithelial cells and induce differentiation changes, such as epithelial-mesenchymal transition (EMT). On the other hand, bone morphogenetic proteins (BMPs) weakly affect epithelial cell growth and do not induce EMT. Smad4 transmits signals from both TGF-β and BMP pathways. Stimulation of Smad4-deficient epithelial cells with TGF-β1 or BMP-7 in the absence or presence of exogenous Smad4, followed by cDNA microarray analysis, revealed 173 mostly Smad4-dependent, TGF-β-, or BMP-responsive genes. Among 25 genes coregulated by both factors, inhibitors of differentiation Id2 and Id3 showed long-term repression by TGF-β and sustained induction by BMP. The opposing regulation of Id genes is critical for proliferative and differentiation responses. Hence, ectopic Id2 or Id3 expression renders epithelial cells refractory to growth inhibition and EMT induced by TGF-β, phenocopying the BMP response. Knockdown of endogenous Id2 or Id3 sensitizes epithelial cells to BMP, leading to robust growth inhibition and induction of transdifferentiation. Thus, Id genes sense Smad signals and create a permissive or refractory nuclear environment that defines decisions of cell fate and proliferation.

scholarly journals The Molecular Mechanism of Epithelial–Mesenchymal Transition for Breast Carcinogenesis

Biomolecules ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 476 ◽  
Author(s):  
Chia-Jung Li ◽  
Pei-Yi Chu ◽  
Giou-Teng Yiang ◽  
Meng-Yu Wu
Keyword(s):  
Epithelial Cells ◽  
Tumor Progression ◽  
Signaling Pathways ◽  
Intracellular Signaling ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
Transforming Growth Factor Β ◽  
Inhibition Of Proliferation ◽  
Mesenchymal Transition

The transforming growth factor-β (TGF-β) signaling pathway plays multiple regulatory roles in the tumorigenesis and development of cancer. TGF-β can inhibit the growth and proliferation of epithelial cells and induce apoptosis, thereby playing a role in inhibiting breast cancer. Therefore, the loss of response in epithelial cells that leads to the inhibition of cell proliferation due to TGF-β is a landmark event in tumorigenesis. As tumors progress, TGF-β can promote tumor cell invasion, metastasis, and drug resistance. At present, the above-mentioned role of TGF-β is related to the interaction of multiple signaling pathways in the cell, which can attenuate or abolish the inhibition of proliferation and apoptosis-promoting effects of TGF-β and enhance its promotion of tumor progression. This article focuses on the molecular mechanisms through which TGF-β interacts with multiple intracellular signaling pathways in tumor progression and the effects of these interactions on tumorigenesis.

scholarly journals Epithelial-Mesenchymal Transition and Metastasis under the Control of Transforming Growth Factor β

2018 ◽  
Vol 19 (11) ◽  
pp. 3672 ◽  
Author(s):  
Yutaro Tsubakihara ◽  
Aristidis Moustakas
Keyword(s):  
Growth Factor ◽  
Tumor Cells ◽  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
Transforming Growth Factor Β ◽  
Basement Membranes ◽  
The Body ◽  
Common Denominator ◽  
Adhesion Forces ◽  
Mesenchymal Transition

Metastasis of tumor cells from primary sites of malignancy to neighboring stromal tissue or distant localities entails in several instances, but not in every case, the epithelial-mesenchymal transition (EMT). EMT weakens the strong adhesion forces between differentiated epithelial cells so that carcinoma cells can achieve solitary or collective motility, which makes the EMT an intuitive mechanism for the initiation of tumor metastasis. EMT initiates after primary oncogenic events lead to secondary secretion of cytokines. The interaction between tumor-secreted cytokines and oncogenic stimuli facilitates EMT progression. A classic case of this mechanism is the cooperation between oncogenic Ras and the transforming growth factor β (TGFβ). The power of TGFβ to mediate EMT during metastasis depends on versatile signaling crosstalk and on the regulation of successive waves of expression of many other cytokines and the progressive remodeling of the extracellular matrix that facilitates motility through basement membranes. Since metastasis involves many organs in the body, whereas EMT affects carcinoma cell differentiation locally, it has frequently been debated whether EMT truly contributes to metastasis. Despite controversies, studies of circulating tumor cells, studies of acquired chemoresistance by metastatic cells, and several (but not all) metastatic animal models, support a link between EMT and metastasis, with TGFβ, often being a common denominator in this link. This article aims at discussing mechanistic cases where TGFβ signaling and EMT facilitate tumor cell dissemination.

scholarly journals The TGFβ-induced phosphorylation and activation of p38 mitogen-activated protein kinase is mediated by MAP3K4 and MAP3K10 but not TAK1

Open Biology ◽  
2013 ◽  
Vol 3 (6) ◽  
pp. 130067 ◽  
Author(s):  
Gopal P. Sapkota
Keyword(s):  
Protein Kinase ◽  
P38 Mapk ◽  
Transforming Growth Factor Beta ◽  
Molecular Mechanisms ◽  
Epithelial To Mesenchymal Transition ◽  
Transforming Growth Factor ◽  
Mitogen Activated Protein Kinase ◽  
Mapk Phosphorylation ◽  
Mesenchymal Transition ◽  
Mitogen Activated Protein

The signalling pathways downstream of the transforming growth factor beta (TGFβ) family of cytokines play critical roles in all aspects of cellular homeostasis. The phosphorylation and activation of p38 mitogen-activated protein kinase (MAPK) has been implicated in TGFβ-induced epithelial-to-mesenchymal transition and apoptosis. The precise molecular mechanisms by which TGFβ cytokines induce the phosphorylation and activation of p38 MAPK are unclear. In this study, I demonstrate that TGFβ-activated kinase 1 (TAK1/MAP3K7) does not play a role in the TGFβ-induced phosphorylation and activation of p38 MAPK in MEFs and HaCaT keratinocytes. Instead, RNAi -mediated depletion of MAP3K4 and MAP3K10 results in the inhibition of the TGFβ-induced p38 MAPK phosphorylation. Furthermore, the depletion of MAP3K10 from cells homozygously knocked-in with a catalytically inactive mutant of MAP3K4 completely abolishes the TGFβ-induced phosphorylation of p38 MAPK, implying that among MAP3Ks, MAP3K4 and MAP3K10 are sufficient for mediating the TGFβ-induced activation of p38 MAPK.

scholarly journals Microparticles as Potential Mediators of High Glucose-Induced Renal Cell Injury

Biomolecules ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 348 ◽  
Author(s):  
Ravindran ◽  
Pasha ◽  
Agouni ◽  
Munusamy
Keyword(s):  
Er Stress ◽  
Signaling Pathways ◽  
Transforming Growth Factor Beta ◽  
High Glucose ◽  
Cell Injury ◽  
Transforming Growth Factor ◽  
Nuclear Translocation ◽  
Epithelial Mesenchymal Transition ◽  
Smooth Muscle Actin ◽  
Mesenchymal Transition

Diabetic nephropathy (DN) is the most common cause of chronic kidney disease worldwide. Activation of signaling pathways such as the mammalian target of rapamycin (mTOR), extracellular signal-regulated kinases (ERK), endoplasmic reticulum (ER) stress, transforming growth factor-beta (TGF-β), and epithelial-mesenchymal transition (EMT), are thought to play a significant role in the etiology of DN. Microparticles (MPs), the small membrane vesicles containing bioactive signals shed by cells upon activation or during apoptosis, are elevated in diabetes and were identified as biomarkers in DN. However, their exact role in the pathophysiology of DN remains unclear. Here, we examined the effect of MPs shed from renal proximal tubular cells (RPTCs) exposed to high glucose conditions on naïve RPTCs in vitro. Our results showed significant increases in the levels of phosphorylated forms of 4E-binding protein 1 and ERK1/2 (the downstream targets of mTOR and ERK pathways), phosphorylated-eIF2α (an ER stress marker), alpha smooth muscle actin (an EMT marker), and phosphorylated-SMAD2 and nuclear translocation of SMAD4 (markers of TGF-β signaling). Together, our findings indicate that MPs activate key signaling pathways in RPTCs under high glucose conditions. Pharmacological interventions to inhibit shedding of MPs from RPTCs might serve as an effective strategy to prevent the progression of DN.

scholarly journals TGF-β Signaling and the Epithelial-Mesenchymal Transition during Palatal Fusion

2018 ◽  
Vol 19 (11) ◽  
pp. 3638 ◽  
Author(s):  
Akira Nakajima ◽  
Charles F. Shuler ◽  
Alexander Gulka ◽  
Jun-ichi Hanai
Keyword(s):  
Cell Fate ◽  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
Genetically Engineered ◽  
Fusion Process ◽  
Mesenchymal Transition ◽  
Morphological Process ◽  
Palatal Fusion ◽  
Genetically Engineered Mice

Signaling by transforming growth factor (TGF)-β plays an important role in development, including in palatogenesis. The dynamic morphological process of palatal fusion occurs to achieve separation of the nasal and oral cavities. Critically and specifically important in palatal fusion are the medial edge epithelial (MEE) cells, which are initially present at the palatal midline seam and over the course of the palate fusion process are lost from the seam, due to cell migration, epithelial-mesenchymal transition (EMT), and/or programed cell death. In order to define the role of TGF-β signaling during this process, several approaches have been utilized, including a small interfering RNA (siRNA) strategy targeting TGF-β receptors in an organ culture context, the use of genetically engineered mice, such as Wnt1-cre/R26R double transgenic mice, and a cell fate tracing through utilization of cell lineage markers. These approaches have permitted investigators to distinguish some specific traits of well-defined cell populations throughout the palatogenic events. In this paper, we summarize the current understanding on the role of TGF-β signaling, and specifically its association with MEE cell fate during palatal fusion. TGF-β is highly regulated both temporally and spatially, with TGF-β3 and Smad2 being the preferentially expressed signaling molecules in the critical cells of the fusion processes. Interestingly, the accessory receptor, TGF-β type 3 receptor, is also critical for palatal fusion, with evidence for its significance provided by Cre-lox systems and siRNA approaches. This suggests the high demand of ligand for this fine-tuned signaling process. We discuss the new insights in the fate of MEE cells in the midline epithelial seam (MES) during the palate fusion process, with a particular focus on the role of TGF-β signaling.

scholarly journals Disruption of Smad4 in Odontoblasts Causes Multiple Keratocystic Odontogenic Tumors and Tooth Malformation in Mice

2009 ◽  
Vol 29 (21) ◽  
pp. 5941-5951 ◽  
Author(s):  
Yuanrong Gao ◽  
Guan Yang ◽  
Tujun Weng ◽  
Juan Du ◽  
Xuejiu Wang ◽  
...  
Keyword(s):  
Transforming Growth Factor Beta ◽  
Hedgehog Signaling ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Bmp Signaling ◽  
Odontogenic Tumors ◽  
High Recurrence Rate ◽  
Signal Molecules ◽  
Cystic Tumors ◽  
Keratocystic Odontogenic Tumors

ABSTRACT Keratocystic odontogenic tumors (KCOTs) are cystic epithelial neoplasias with a high recurrence rate. However, the molecular mechanisms underlying the initiation and progression of KCOTs are still largely unknown. Here, we show that specific ablation of Smad4 in odontoblasts unexpectedly resulted in spontaneous KCOTs in mice. The mutant mice exhibited malformed teeth characterized by fractured incisors and truncated molar roots. These abnormalities were mainly caused by disrupted odontoblast differentiation that led to irregular dentin formation. The cystic tumors arising from the reactivation of epithelial rests of Malassez (ERM), in which Smad4 remained intact, proliferated and formed stratified and differentiated squamous epithelia that exhibited a dramatic upregulation of Hedgehog signaling. Odontoblasts, which are responsive to transforming growth factor beta (TGF-β)/bone morphogenetic protein (BMP) signals, may produce signal molecules to inhibit the activation of ERM. Indeed, we observed a downregulation of BMP signals from Smad4 mutant odontoblasts to the adjacent Hertwig's epithelial root sheath (HERS). Intriguingly, KCOTs frequently emerged from Smad4-deficient ERM in keratinocyte-specific Smad4 knockout mice, suggesting a novel mechanism in which reciprocal TGF-β/BMP signaling between odontoblasts and HERS was required for tooth root development and suppression of KCOT formation. These findings provide insight into the genetic basis underlying KCOTs and have important implications for new directions in KCOT treatment.

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