Regulation of Programmed Cell Death by Basement Membranes in Embryonic Development

The formation of the proamniotic cavity in the mammalian embryo is the earliest of many instances throughout development in which programmed cell death and the formation of epithelia play fundamental roles (Coucouvanis, E., and G.R. Martin. 1995. Cell. 83:279–287). To determine the role of the basement membrane (BM) in cavitation, we use embryoid bodies derived from mouse embryonic stem cells in which the LAMC1 genes have been inactivated to prevent BM deposition (Smyth, N., H.S. Vatansever, P. Murray, M. Meyer, C. Frie, M. Paulsson, and D. Edgar. 1999. J. Cell Biol. 144:151–610). We demonstrate here that LAMC1−/− embryoid bodies are unable to cavitate, and do not form an epiblast epithelium in the absence of a BM, although both embryonic ectodermal cells and extraembryonic endodermal cells do differentiate, as evidenced by the expression of cell-specific markers. Acceleration or rescue of BM deposition by exogenous laminin in wild-type or LAMC1−/− embryoid bodies, respectively, results in cavitation that is temporally and spatially associated with restoration of epiblast epithelial development. We conclude that the BM not only directly regulates development of epiblast epithelial cells, but also indirectly regulates the programmed cell death necessary for cavity formation.

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Regulation of the differentiation and behaviour of extra-embryonic endodermal cells by basement membranes

Journal of Cell Science ◽

10.1242/jcs.114.5.931 ◽

2001 ◽

Vol 114 (5) ◽

pp. 931-939 ◽

Cited By ~ 2

Author(s):

P. Murray ◽

D. Edgar

Keyword(s):

Stem Cells ◽

Basement Membrane ◽

Embryonic Stem ◽

Basement Membranes ◽

Embryoid Bodies ◽

Endodermal Differentiation ◽

And Migration ◽

The Individual ◽

Endodermal Cells

Both the extracellular matrix and parathyroid hormone-related peptide (PTHrP) have been implicated in the differentiation and migration of extra-embryonic endodermal cells in the pre-implantation mammalian blastocyst. In order to define the individual roles and interactions between these factors in endodermal differentiation, we have used embryoid bodies derived from Lamc1(-/-) embryonic stem cells that lack basement membranes. The results show that in the absence of basement membranes, increased numbers of both visceral and parietal endodermal cells differentiate, but they fail to form organised epithelia. Furthermore, although parietal endodermal cells only migrate away from control embryoid bodies in the presence of PTHrP, they readily migrate from Lamc1(-/-) embryoid bodies in the absence of PTHrP, and this migration is unaffected by PTHrP. Thus, the basement membrane between epiblast and extra-embryonic endoderm is required for the proper organisation of visceral and parietal endodermal cells and also restricts their differentiation to maintain the population of primitive endodermal stem cells. Moreover, this basement membrane inhibits migration of parietal endodermal cells, the role of PTHrP being to stimulate delamination of parietal endodermal cells from the basement membrane rather than promoting migration per se.

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Neural Differentiation Is Inhibited through HIF1α/β-Catenin Signaling in Embryoid Bodies

Stem Cells International ◽

10.1155/2017/8715798 ◽

2017 ◽

Vol 2017 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Josef Večeřa ◽

Jana Kudová ◽

Jan Kučera ◽

Lukáš Kubala ◽

Jiří Pacherník

Keyword(s):

Stem Cells ◽

Cell Fate ◽

Neural Differentiation ◽

Embryonic Stem ◽

Direct Interaction ◽

Embryoid Bodies ◽

Nuclear Fraction ◽

Wild Type ◽

Spontaneous Differentiation

Extensive research in the field of stem cells and developmental biology has revealed evidence of the role of hypoxia as an important factor regulating self-renewal and differentiation. However, comprehensive information about the exact hypoxia-mediated regulatory mechanism of stem cell fate during early embryonic development is still missing. Using a model of embryoid bodies (EBs) derived from murine embryonic stem cells (ESC), we here tried to encrypt the role of hypoxia-inducible factor 1α (HIF1α) in neural fate during spontaneous differentiation. EBs derived from ESC with the ablated gene for HIF1α had abnormally increased neuronal characteristics during differentiation. An increased neural phenotype in Hif1α−/− EBs was accompanied by the disruption of β-catenin signaling together with the increased cytoplasmic degradation of β-catenin. The knock-in of Hif1α, as well as β-catenin ectopic overexpression in Hif1α−/− EBs, induced a reduction in neural markers to the levels observed in wild-type EBs. Interestingly, direct interaction between HIF1α and β-catenin was demonstrated by immunoprecipitation analysis of the nuclear fraction of wild-type EBs. Together, these results emphasize the regulatory role of HIF1α in β-catenin stabilization during spontaneous differentiation, which seems to be a crucial mechanism for the natural inhibition of premature neural differentiation.

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Faculty Opinions recommendation of New Arabidopsis thaliana cytochrome c partners: a look into the elusive role of cytochrome c in programmed cell death in plants.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718104360.793488383 ◽

2013 ◽

Author(s):

Daniel Gallie

Keyword(s):

Arabidopsis Thaliana ◽

Cell Death ◽

Cytochrome C ◽

Programmed Cell Death

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The role of programmed cell death ligand-1/ programmed cell death-1 (PD-L1/PD-1) in HPV-induced cervical cancer and potential for their use in blockade therapy

Current Medicinal Chemistry ◽

10.2174/0929867327666200128105459 ◽

2020 ◽

Vol 27 ◽

Cited By ~ 1

Author(s):

Lifang Zhang ◽

Yu Zhao ◽

Quanmei Tu ◽

Xiangyang Xue ◽

Xueqiong Zhu ◽

...

Keyword(s):

Cervical Cancer ◽

Cell Death ◽

Programmed Cell Death ◽

Immune Escape ◽

Hypoxia Inducible Factor ◽

Hpv Infection ◽

Advanced Cervical Cancer ◽

Cervical Carcinogenesis ◽

Programmed Cell Death 1

Background: Cervical cancer induced by infection with human papillomavirus (HPV) remains a leading cause of mortality for women worldwide although preventive vaccines and early diagnosis have reduced morbidity and mortality. Advanced cervical cancer can only be treated with either chemotherapy or radiotherapy but outcomes are poor. The median survival for advanced cervical cancer patients is only 16.8 months. Methods: We undertook a structural search of peer-reviewed published studies based on 1). Characteristics of programmed cell death ligand-1/programmed cell death-1(PD-L1/PD-1) expression in cervical cancer and upstream regulatory signals of PD-L1/PD-1 expression, 2). The role of the PD-L1/PD-1 axis in cervical carcinogenesis induced by HPV infection and 3). Whether the PD-L1/PD-1 axis has emerged as a potential target for cervical cancer therapies. Results: One hundred and twenty-six published papers were included in the review, demonstrating that expression of PD-L1/PD-1 is associated with HPV-caused cancer, especially with HPV 16 and 18 which account for approximately 70% of cervical cancer cases. HPV E5/E6/E7 oncogenes activate multiple signaling pathways including PI3K/AKT, MAPK, hypoxia-inducible factor 1α, STAT3/NF-kB and MicroRNAs, which regulate PD-L1/PD-1 axis to promote HPV-induced cervical carcinogenesis. The PD-L1/PD-1 axis plays a crucial role in immune escape of cervical cancer through inhibition of host immune response. creating an "immune-privileged" site for initial viral infection and subsequent adaptive immune resistance, which provides a rationale for therapeutic blockade of this axis in HPV-positive cancers. Currently, Phase I/II clinical trials evaluating the effects of PD-L1/PD-1 targeted therapies are in progress for cervical carcinoma, which provide an important opportunity for the application of anti-PD-L1/anti-PD-1 antibodies in cervical cancer treatment. Conclusion: Recent research developments have led to an entirely new class of drugs using antibodies against the PD-L1/PD-1 thus promoting the body’s immune system to fight the cancer. The expression and roles of the PD-L1/ PD-1 axis in the progression of cervical cancer provide great potential for using PD-L1/PD-1 antibodies as a targeted cancer therapy.

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Ozone-Induced Cell Death in Tobacco Cultivar Bel W3 Plants. The Role of Programmed Cell Death in Lesion Formation

PLANT PHYSIOLOGY ◽

10.1104/pp.103.026591 ◽

2003 ◽

Vol 133 (3) ◽

pp. 1122-1134 ◽

Cited By ~ 123

Author(s):

Stefania Pasqualini ◽

Claudia Piccioni ◽

Lara Reale ◽

Luisa Ederli ◽

Guido Della Torre ◽

...

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Lesion Formation ◽

Tobacco Cultivar

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Salicylic Acid Accumulation Controlled by LSD1 Is Essential in Triggering Cell Death in Response to Abiotic Stress

Cells ◽

10.3390/cells10040962 ◽

2021 ◽

Vol 10 (4) ◽

pp. 962

Author(s):

Maciej Jerzy Bernacki ◽

Anna Rusaczonek ◽

Weronika Czarnocka ◽

Stanisław Karpiński

Keyword(s):

Cell Death ◽

Salicylic Acid ◽

Abiotic Stress ◽

Wild Type ◽

Pr Genes ◽

Genes Expression ◽

Salicylic Acid Accumulation ◽

Cell Death Phenotype ◽

Insight Into

Salicylic acid (SA) is well known hormonal molecule involved in cell death regulation. In response to a broad range of environmental factors (e.g., high light, UV, pathogens attack), plants accumulate SA, which participates in cell death induction and spread in some foliar cells. LESION SIMULATING DISEASE 1 (LSD1) is one of the best-known cell death regulators in Arabidopsis thaliana. The lsd1 mutant, lacking functional LSD1 protein, accumulates SA and is conditionally susceptible to many biotic and abiotic stresses. In order to get more insight into the role of LSD1-dependent regulation of SA accumulation during cell death, we crossed the lsd1 with the sid2 mutant, caring mutation in ISOCHORISMATE SYNTHASE 1(ICS1) gene and having deregulated SA synthesis, and with plants expressing the bacterial nahG gene and thus decomposing SA to catechol. In response to UV A+B irradiation, the lsd1 mutant exhibited clear cell death phenotype, which was reversed in lsd1/sid2 and lsd1/NahG plants. The expression of PR-genes and the H2O2 content in UV-treated lsd1 were significantly higher when compared with the wild type. In contrast, lsd1/sid2 and lsd1/NahG plants demonstrated comparability with the wild-type level of PR-genes expression and H2O2. Our results demonstrate that SA accumulation is crucial for triggering cell death in lsd1, while the reduction of excessive SA accumulation may lead to a greater tolerance toward abiotic stress.

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Bub1 mediates cell death in response to chromosome missegregation and acts to suppress spontaneous tumorigenesis

The Journal of Cell Biology ◽

10.1083/jcb.200706015 ◽

2007 ◽

Vol 179 (2) ◽

pp. 255-267 ◽

Cited By ~ 147

Author(s):

Karthik Jeganathan ◽

Liviu Malureanu ◽

Darren J. Baker ◽

Susan C. Abraham ◽

Jan M. van Deursen

Keyword(s):

Cell Death ◽

Chromosome Segregation ◽

Physiological Role ◽

Mitotic Checkpoint ◽

Critical Threshold ◽

Wild Type ◽

Checkpoint Protein ◽

Chromosome Missegregation ◽

Mitotic Checkpoint Protein

The physiological role of the mitotic checkpoint protein Bub1 is unknown. To study this role, we generated a series of mutant mice with a gradient of reduced Bub1 expression using wild-type, hypomorphic, and knockout alleles. Bub1 hypomorphic mice are viable, fertile, and overtly normal despite weakened mitotic checkpoint activity and high percentages of aneuploid cells. Bub1 haploinsufficient mice, which have a milder reduction in Bub1 protein than Bub1 hypomorphic mice, also exhibit reduced checkpoint activity and increased aneuploidy, but to a lesser extent. Although cells from Bub1 hypomorphic and haploinsufficient mice have similar rates of chromosome missegregation, cell death after an aberrant separation decreases dramatically with declining Bub1 levels. Importantly, Bub1 hypomorphic mice are highly susceptible to spontaneous tumors, whereas Bub1 haploinsufficient mice are not. These findings demonstrate that loss of Bub1 below a critical threshold drives spontaneous tumorigenesis and suggest that in addition to ensuring proper chromosome segregation, Bub1 is important for mediating cell death when chromosomes missegregate.

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