p53 drives premature neuronal differentiation in response to radiation-induced DNA damage during early neurogenesis

Abstractp53 regulates the cellular DNA damage response (DDR). Hyperactivation of p53 during embryonic development, however, can lead to a range of developmental defects including microcephaly. Here, we induce microcephaly by acute irradiation of mouse fetuses at the onset of neurogenesis. Besides a classical DDR culminating in massive apoptosis, we observe ectopic neurons in the subventricular zone in the brains of irradiated mice, indicative of premature neuronal differentiation. A transcriptomic study indicates that p53 activates both DDR genes and differentiation-associated genes. In line with this, mice with a targeted inactivation of Trp53 in the dorsal forebrain, do not show this ectopic phenotype and partially restore brain size after irradiation. Irradiation furthermore induces an epithelial-to-mesenchymal transition-like process resembling the radiation-induced proneural-mesenchymal transition in glioma and glioma stem-like cells. Our results demonstrate a critical role for p53 beyond the DDR as a regulator of neural progenitor cell fate in response to DNA damage.

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Mnt represses epithelial identity to promote Epithelial to Mesenchymal Transition

Molecular and Cellular Biology ◽

10.1128/mcb.00183-21 ◽

2021 ◽

Author(s):

Deborah P. Lavin ◽

Leila Abassi ◽

Mohammed Inayatullah ◽

Vijay K. Tiwari

Keyword(s):

Epithelial Cells ◽

Cell Fate ◽

Cancer Metastasis ◽

Epithelial To Mesenchymal Transition ◽

Mammary Epithelial Cells ◽

Morphological Changes ◽

Critical Role ◽

Chromatin Accessibility ◽

Mammary Epithelial ◽

Mesenchymal Transition

The multi-step process of epithelial to mesenchymal transition (EMT), whereby static epithelial cells become migratory mesenchymal cells, plays a critical role during various developmental contexts, wound healing, and pathological conditions such as cancer metastasis. Despite the established function of basic helix-loop-helix (bHLH) transcription factors (TFs) in cell-fate determination, only a few have been examined for their role in EMT. Here, using transcriptome analysis of distinct stages during stepwise progression of TGFβ-induced EMT in mammary epithelial cells, we revealed distinct categories of bHLH TFs that show differential expression kinetics during EMT. Using a siRNA-mediated functional screen for bHLH TFs during EMT, we found Max network transcription repressor (MNT) to be essential for EMT in mammary epithelial cells. We show that the depletion of MNT blocks TGFβ-induced morphological changes during EMT, and this is accompanied by de-repression of a large number of epithelial genes. We show that MNT mediates the repression of epithelial identity genes during EMT by recruiting HDAC1 and mediating the loss of H3K27ac and chromatin accessibility. Lastly, we show that MNT is expressed at higher levels in EMT-High breast cancer cells and is required for their migration. Taken together, these findings establish MNT as a critical regulator of cell-fate changes during mammary EMT.

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Molecular regulation of Snai2 in development and disease

Journal of Cell Science ◽

10.1242/jcs.235127 ◽

2019 ◽

Vol 132 (23) ◽

Author(s):

Wenhui Zhou ◽

Kayla M. Gross ◽

Charlotte Kuperwasser

Keyword(s):

Transcription Factor ◽

Cell Biology ◽

Molecular Mechanisms ◽

Epithelial To Mesenchymal Transition ◽

Zinc Finger Protein ◽

Main Role ◽

Biological Processes ◽

Developmental Defects ◽

Mesenchymal Transition ◽

Damage Repair

ABSTRACT The transcription factor Snai2, encoded by the SNAI2 gene, is an evolutionarily conserved C2H2 zinc finger protein that orchestrates biological processes critical to tissue development and tumorigenesis. Initially characterized as a prototypical epithelial-to-mesenchymal transition (EMT) transcription factor, Snai2 has been shown more recently to participate in a wider variety of biological processes, including tumor metastasis, stem and/or progenitor cell biology, cellular differentiation, vascular remodeling and DNA damage repair. The main role of Snai2 in controlling such processes involves facilitating the epigenetic regulation of transcriptional programs, and, as such, its dysregulation manifests in developmental defects, disruption of tissue homeostasis, and other disease conditions. Here, we discuss our current understanding of the molecular mechanisms regulating Snai2 expression, abundance and activity. In addition, we outline how these mechanisms contribute to disease phenotypes or how they may impact rational therapeutic targeting of Snai2 dysregulation in human disease.

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Proteomic Analysis of Zeb1 Interactome in Breast Carcinoma Cells

Molecules ◽

10.3390/molecules26113143 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3143

Author(s):

Sergey E. Parfenyev ◽

Sergey V. Shabelnikov ◽

Danila Y. Pozdnyakov ◽

Olga O. Gnedina ◽

Leonid S. Adonin ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Epithelial To Mesenchymal Transition ◽

Critical Role ◽

Malignant Neoplasm ◽

Malignant Neoplasms ◽

Breast Cancer Patients ◽

Survival Prognosis ◽

Mesenchymal Transition ◽

Wide Range

Breast cancer is the most frequently diagnosed malignant neoplasm and the second leading cause of cancer death among women. Epithelial-to-mesenchymal Transition (EMT) plays a critical role in the organism development, providing cell migration and tissue formation. However, its erroneous activation in malignancies can serve as the basis for the dissemination of cancer cells and metastasis. The Zeb1 transcription factor, which regulates the EMT activation, has been shown to play an essential role in malignant transformation. This factor is involved in many signaling pathways that influence a wide range of cellular functions via interacting with many proteins that affect its transcriptional functions. Importantly, the interactome of Zeb1 depends on the cellular context. Here, using the inducible expression of Zeb1 in epithelial breast cancer cells, we identified a substantial list of novel potential Zeb1 interaction partners, including proteins involved in the formation of malignant neoplasms, such as ATP-dependent RNA helicase DDX17and a component of the NURD repressor complex, CTBP2. We confirmed the presence of the selected interactors by immunoblotting with specific antibodies. Further, we demonstrated that co-expression of Zeb1 and CTBP2 in breast cancer patients correlated with the poor survival prognosis, thus signifying the functionality of the Zeb1–CTBP2 interaction.

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A radiosensitizer, gallotannin-rich extract from Bouea macrophylla seeds, inhibits radiation-induced epithelial-mesenchymal transition in breast cancer cells

BMC Complementary Medicine and Therapies ◽

10.1186/s12906-021-03363-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Jiraporn Kantapan ◽

Siwaphon Paksee ◽

Aphidet Duangya ◽

Padchanee Sangthong ◽

Sittiruk Roytrakul ◽

...

Keyword(s):

Breast Cancer ◽

Dna Damage ◽

Cell Death ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Epithelial Mesenchymal Transition ◽

Breast Cancer Cell Lines ◽

Mesenchymal Transition ◽

Mammosphere Formation ◽

Radiation Induced

Abstract Background Radioresistance can pose a significant obstacle to the effective treatment of breast cancers. Epithelial–mesenchymal transition (EMT) is a critical step in the acquisition of stem cell traits and radioresistance. Here, we investigated whether Maprang seed extract (MPSE), a gallotannin-rich extract of seed from Bouea macrophylla Griffith, could inhibit the radiation-induced EMT process and enhance the radiosensitivity of breast cancer cells. Methods Breast cancer cells were pre-treated with MPSE before irradiation (IR), the radiosensitizing activity of MPSE was assessed using the colony formation assay. Radiation-induced EMT and stemness phenotype were identified using breast cancer stem cells (CSCs) marker (CD24−/low/CD44+) and mammosphere formation assay. Cell motility was determined via the wound healing assay and transwell migration. Radiation-induced cell death was assessed via the apoptosis assay and SA-β-galactosidase staining for cellular senescence. CSCs- and EMT-related genes were confirmed by real-time PCR (qPCR) and Western blotting. Results Pre-treated with MPSE before irradiation could reduce the clonogenic activity and enhance radiosensitivity of breast cancer cell lines with sensitization enhancement ratios (SERs) of 2.33 and 1.35 for MCF7 and MDA-MB231cells, respectively. Pretreatment of breast cancer cells followed by IR resulted in an increased level of DNA damage maker (γ-H2A histone family member) and enhanced radiation-induced cell death. Irradiation induced EMT process, which displayed a significant EMT phenotype with a down-regulated epithelial marker E-cadherin and up-regulated mesenchymal marker vimentin in comparison with untreated breast cancer cells. Notably, we observed that pretreatment with MPSE attenuated the radiation-induced EMT process and decrease some stemness-like properties characterized by mammosphere formation and the CSC marker. Furthermore, pretreatment with MPSE attenuated the radiation-induced activation of the pro-survival pathway by decrease the expression of phosphorylation of ERK and AKT and sensitized breast cancer cells to radiation. Conclusion MPSE enhanced the radiosensitivity of breast cancer cells by enhancing IR-induced DNA damage and cell death, and attenuating the IR-induced EMT process and stemness phenotype via targeting survival pathways PI3K/AKT and MAPK in irradiated breast cancer cells. Our findings describe a novel strategy for increasing the efficacy of radiotherapy for breast cancer patients using a safer and low-cost natural product, MPSE.

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

eLife ◽

10.7554/elife.14847 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 21

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.

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Deeper Insight in Metastatic Cancer progression;Epithelial-to-Mesenchymal Transition and Genomic Instability: implications on treatment resistance

Current Molecular Medicine ◽

10.2174/1566524021666210202114844 ◽

2021 ◽

Vol 21 ◽

Author(s):

Kenneth Omabe ◽

Sandra Uduituma ◽

David Igwe ◽

Maxwell Omabe

Keyword(s):

Dna Damage ◽

Cancer Treatment ◽

Epithelial To Mesenchymal Transition ◽

Dna Damage Repair ◽

Treatment Resistance ◽

Therapy Resistance ◽

Cellular Reprogramming ◽

Repair System ◽

Mesenchymal Transition ◽

Damage Repair

: Therapy resistance remains the major obstacle to successful cancer treatment. Epithelial-to- mesenchymal transition [EMT], a cellular reprogramming process involved in embryogenesis and organ development and regulated by a number of transcriptional factors [EMT-TFs] such as ZEB1/2, is recognized for its role in tumor progression and metastasis. Recently, a growing body of evidence has implicated EMT in cancer therapy resistance but the actual mechanism that underlie this finding has remained elusive. For example, whether it is, the EMT states in itself or the EMT-TFs that modulates chemo or radio-resistance in cancer is still contentious. Here, we summarise the molecular mechanisms of EMT program and chemotherapeutic resistance in cancer with specific reference to DNA damage response [DDR]. We provide an insight into the molecular interplay that exist between EMT program and DNA repair machinery in cancer and how this interaction influences therapeutic response. We review conflicting studies linking EMT and drug resistance via the DNA damage repair axis. We draw scientific evidence demonstrating how several molecular signalling, including EMT-TFs work in operational harmony to induce EMT and confer stemness properties on the EMT-susceptible cells. We highlight the role of enhanced DNA damage repair system associated with EMT-derived stem cell-like states in promoting therapy resistance and suggest a multi-targeting modality in combating cancer treatment resistance.

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

Cells Tissues Organs ◽

10.1159/000512277 ◽

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 (Ca2+) signaling plays a critical role in dictating the adaptive metastatic cell behavior comprising of cell migration, invasion, angiogenesis, and intravasation. By modulating EMT, Ca2+ signaling can regulate the complexity and dynamics of events leading to metastasis. This review summarizes the role of Ca2+ signal remodeling in the regulation of EMT and metastasis in cancer.

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The Role of Nitric Oxide in Cancer: Master Regulator or NOt?

International Journal of Molecular Sciences ◽

10.3390/ijms21249393 ◽

2020 ◽

Vol 21 (24) ◽

pp. 9393

Author(s):

Faizan H. Khan ◽

Eoin Dervan ◽

Dibyangana D. Bhattacharyya ◽

Jake D. McAuliffe ◽

Katrina M. Miranda ◽

...

Keyword(s):

Nitric Oxide ◽

Cell Cycle ◽

Dna Damage ◽

Cell Cycle Arrest ◽

Cell Cycle Progression ◽

Epithelial To Mesenchymal Transition ◽

Tumour Microenvironment ◽

Master Regulator ◽

Mesenchymal Transition ◽

Cycle Arrest

Nitric oxide (NO) is a key player in both the development and suppression of tumourigenesis depending on the source and concentration of NO. In this review, we discuss the mechanisms by which NO induces DNA damage, influences the DNA damage repair response, and subsequently modulates cell cycle arrest. In some circumstances, NO induces cell cycle arrest and apoptosis protecting against tumourigenesis. NO in other scenarios can cause a delay in cell cycle progression, allowing for aberrant DNA repair that promotes the accumulation of mutations and tumour heterogeneity. Within the tumour microenvironment, low to moderate levels of NO derived from tumour and endothelial cells can activate angiogenesis and epithelial-to-mesenchymal transition, promoting an aggressive phenotype. In contrast, high levels of NO derived from inducible nitric oxide synthase (iNOS) expressing M1 and Th1 polarised macrophages and lymphocytes may exert an anti-tumour effect protecting against cancer. It is important to note that the existing evidence on immunomodulation is mainly based on murine iNOS studies which produce higher fluxes of NO than human iNOS. Finally, we discuss different strategies to target NO related pathways therapeutically. Collectively, we present a picture of NO as a master regulator of cancer development and progression.

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Epithelial to Mesenchymal Transition Is Activated in Metastatic Pheochromocytomas and Paragangliomas Caused by SDHB Gene Mutations

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2011-3437 ◽

2012 ◽

Vol 97 (6) ◽

pp. E954-E962 ◽

Cited By ~ 57

Author(s):

Céline Loriot ◽

Nelly Burnichon ◽

Noémie Gadessaud ◽

Laure Vescovo ◽

Laurence Amar ◽

...

Keyword(s):

Epithelial To Mesenchymal Transition ◽

Nuclear Translocation ◽

Critical Role ◽

Gene Mutations ◽

Unsupervised Classification ◽

Metastatic Tumors ◽

Mesenchymal Transition ◽

Predictive Risk Factor ◽

Sdhb Gene ◽

Predictive Risk

Context: Pheochromocytoma and paraganglioma are rare neural-crest-derived tumors. They are metastatic in 15% of cases, and the identification of a germline mutation in the SDHB gene is a predictive risk factor for malignancy and poor prognosis. To date, the link between SDHB mutations and malignancy is still missing. Objective: Epithelial to mesenchymal transition (EMT) is a developmental event, reactivated in cancer cells to promote cell mobility and invasiveness. The aim of this study was to address the participation of EMT in the metastatic evolution of pheochromocytoma/paraganglioma. Design and Patients: Transcriptomic profiling of EMT was performed on 188 tumor samples, using a set of 94 genes implicated in this pathway. Activation of EMT was further confirmed at protein level by immunohistochemistry in a second set of 93 tumors. Results: Hierarchical unsupervised classification showed that most SDHB-metastatic samples clustered together, indicating that EMT is differently regulated in these tumors. Major actors of EMT, metalloproteases and components of cellular junctions, were either up-regulated (LOXL2, TWIST, TCF3, MMP2, and MMP1) or down-regulated (KRT19 and CDH2) in SDHB-metastatic tumors compared with nonmetastatic ones. Interestingly, within metastatic tumors, most of these genes (LOXL2, TWIST, TCF3, MMP2, and KRT19) also allowed us to discriminate SDHB-mutated from non-SDHB-related tumors. In the second set of tumors, we studied Snail1/2 expression by immunohistochemistry and observed its specific nuclear translocation in all SDHB-metastatic tumors. Conclusion: We have identified the first pathway that distinguishes SDHB-metastatic from all other types of pheochromocytomas/paragangliomas and suggest that activation of the EMT process might play a critical role in the particularly invasive phenotype of this group of tumors.

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