scholarly journals FKBP51 Affects TNF-Related Apoptosis Inducing Ligand Response in Melanoma

2021 ◽  
Vol 9 ◽  
Author(s):  
Martina Tufano ◽  
Elena Cesaro ◽  
Rosanna Martinelli ◽  
Roberto Pacelli ◽  
Simona Romano ◽  
...  
Keyword(s):  
Cell Death ◽  
Immune Cells ◽  
Histone Deacetylases ◽  
Melanoma Cells ◽  
Transcriptional Level ◽  
Cell Death Pathways ◽  
Yin Yang 1 ◽  
Immune Precipitation ◽  
Induced Apoptosis ◽  
Repressor Activity

Melanoma is one of the most immunogenic tumors and has the highest potential to elicit specific adaptive antitumor immune responses. Immune cells induce apoptosis of cancer cells either by soluble factors or by triggering cell-death pathways. Melanoma cells exploit multiple mechanisms to escape immune system tumoricidal control. FKBP51 is a relevant pro-oncogenic factor of melanoma cells supporting NF-κB-mediated resistance and cancer stemness/invasion epigenetic programs. Herein, we show that FKBP51-silencing increases TNF-related apoptosis-inducing ligand (TRAIL)-R2 (DR5) expression and sensitizes melanoma cells to TRAIL-induced apoptosis. Consistent with the general increase in histone deacetylases, as by the proteomic profile, the immune precipitation assay showed decreased acetyl-Yin Yang 1 (YY1) after FKBP51 depletion, suggesting an impaired repressor activity of this transcription factor. ChIP assay supported this hypothesis. Compared with non-silenced cells, a reduced acetyl-YY1 was found on the DR5 promoter, resulting in increased DR5 transcript levels. Using Crispr/Cas9 knockout (KO) melanoma cells, we confirmed the negative regulation of DR5 by FKBP51. We also show that KO cells displayed reduced levels of acetyl-EP300 responsible for YY1 acetylation, along with reduced acetyl-YY1. Reconstituting FKBP51 levels contrasted the effects of KO on DR5, acetyl-YY1, and acetyl-EP300 levels. In conclusion, our finding shows that FKBP51 reduces DR5 expression at the transcriptional level by promoting YY1 repressor activity. Our study supports the conclusion that targeting FKBP51 increases the expression level of DR5 and sensitivity to TRAIL-induced cell death, which can improve the tumoricidal action of immune cells.

Caspase-dependent and -independent pathways for cadmium-induced apoptosis in cultured kidney proximal tubule cells

2006 ◽  
Vol 291 (4) ◽  
pp. F823-F832 ◽  
Author(s):  
Wing-Kee Lee ◽  
Marouan Abouhamed ◽  
Frank Thévenod
Keyword(s):  
Cell Death ◽  
Proximal Tubule ◽  
Rat Kidney ◽  
Cadmium Concentration ◽  
Nuclear Staining ◽  
Kidney Proximal Tubule ◽  
Cell Death Pathways ◽  
Cyt C ◽  
Induced Apoptosis ◽  
Apoptosis Inducing Factor

The nephrotoxic metal cadmium at micromolar concentrations induces apoptosis of rat kidney proximal tubule (PT) cells within 3–6 h of exposure. The underlying cell death pathways remain poorly defined. Using Hoechst 33342/ethidium bromide nuclear staining and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) cell death assays, 10–50 μM cadmium induced apoptosis of immortalized rat kidney cells derived from the S1-segment of PT at 6 and 24 h, but necrosis at 24 h only. Cadmium (10–50 μM) also caused mitochondrial cytochrome c (cyt. c)- and apoptosis-inducing factor release at 24 h, but not at 6 h, as measured by immunofluorescence imaging and immunoblotting. Caspases-9 and -3 were activated only by 10 μM cadmium for 24 h, and accordingly apoptosis was significantly reduced by the respective inhibitors (z-LEHD-fmk, z-DEVD-fmk; 10 μg/ml) at 24 h, but not at 6 h, without affecting necrosis. At 6 h, 10 μM cadmium increased the activity of the calcium-activated protease calpain, but not at 24 h, and calpain inhibitors (ALLN, PD 150606; 10–30 μM) blocked apoptosis by 10 μM cadmium at 3–6 h. However, PD-150606 also attenuated caspase-3 activity and apoptosis at 24 h, suggesting calpain-dependent caspase activation. Thus cadmium-induced apoptosis of PT cells involves a complex and sensitive interplay of signaling cascades involving mitochondrial proapoptotic factors, calpains and caspases, whose activation is also determined by cadmium concentration and the duration of cadmium exposure.

scholarly journals Varicella-Zoster Virus ORF63 Protects Human Neuronal and Keratinocyte Cell Lines from Apoptosis and Changes Its Localization upon Apoptosis Induction

2018 ◽  
Vol 92 (12) ◽  
pp. e00338-18 ◽  
Author(s):  
Chelsea Gerada ◽  
Megan Steain ◽  
Brian P. McSharry ◽  
Barry Slobedman ◽  
Allison Abendroth
Keyword(s):  
Cell Death ◽  
Varicella Zoster Virus ◽  
Gene Product ◽  
Postherpetic Neuralgia ◽  
Hacat Cells ◽  
Apoptosis Induction ◽  
Varicella Zoster ◽  
Cell Death Pathways ◽  
Keratinocyte Cell ◽  
Induced Apoptosis

ABSTRACTThere are many facets of varicella-zoster virus (VZV) pathogenesis that are not fully understood, such as the mechanisms involved in the establishment of lifelong latency, reactivation, and development of serious conditions like postherpetic neuralgia (PHN). Virus-encoded modulation of apoptosis has been suggested to play an important role in these processes. VZV open reading frame 63 (ORF63) has been shown to modulate apoptosis in a cell-type-specific manner, but the impact of ORF63 on cell death pathways has not been examined in isolation in the context of human cells. We sought to elucidate the effect of VZV ORF63 on apoptosis induction in human neuron and keratinocyte cell lines. VZV ORF63 was shown to protect differentiated SH-SY5Y neuronal cells against staurosporine-induced apoptosis. In addition, VZV infection did not induce high levels of apoptosis in the HaCaT human keratinocyte line, highlighting a delay in apoptosis induction. VZV ORF63 was shown to protect HaCaT cells against both staurosporine- and Fas ligand-induced apoptosis. Confocal microscopy was utilized to examine VZV ORF63 localization during apoptosis induction. In VZV infection and ORF63 expression alone, VZV ORF63 became more cytoplasmic, with aggregate formation during apoptosis induction. Taken together, this suggests that VZV ORF63 protects both differentiated SH-SY5Y cells and HaCaT cells from apoptosis induction and may mediate this effect through its localization change during apoptosis. VZV ORF63 is a prominent VZV gene product in both productive and latent infection and thus may play a critical role in VZV pathogenesis by aiding neuron and keratinocyte survival.IMPORTANCEVZV, a human-specific alphaherpesvirus, causes chicken pox during primary infection and establishes lifelong latency in the dorsal root ganglia (DRG). Reactivation of VZV causes shingles, which is often followed by a prolonged pain syndrome called postherpetic neuralgia. It has been suggested that the ability of the virus to modulate cell death pathways is linked to its ability to establish latency and reactivate. The significance of our research lies in investigating the ability of ORF63, a VZV gene product, to inhibit apoptosis in novel cell types crucial for VZV pathogenesis. This will allow an increased understanding of critical enigmatic components of VZV pathogenesis.

scholarly journals Downregulation of PUMA underlies resistance to FGFR1 inhibitors in the stem cell leukemia/lymphoma syndrome

2020 ◽  
Vol 11 (10) ◽  
Author(s):  
Yun Liu ◽  
Baohuan Cai ◽  
Yating Chong ◽  
Hualei Zhang ◽  
Chesley-Anne Kemp ◽  
...  
Keyword(s):  
Cell Death ◽  
Kinase Inhibitors ◽  
Leukemic Cells ◽  
Direct Role ◽  
Genetic Changes ◽  
Cell Death Pathways ◽  
Pten Deletion ◽  
Induced Apoptosis ◽  
Resistant Cells

Abstract Resistance to molecular therapies frequently occur due to genetic changes affecting the targeted pathway. In myeloid and lymphoid leukemias/lymphomas resulting from constitutive activation of FGFR1 kinases, resistance has been shown to be due either to mutations in FGFR1 or deletions of PTEN. RNA-Seq analysis of the resistant clones demonstrates expression changes in cell death pathways centering on the p53 upregulated modulator of apoptosis (Puma) protein. Treatment with different tyrosine kinase inhibitors (TKIs) revealed that, in both FGFR1 mutation and Pten deletion-mediated resistance, sustained Akt activation in resistant cells leads to compromised Puma activation, resulting in suppression of TKI-induced apoptosis. This suppression of Puma is achieved as a result of sequestration of inactivated p-Foxo3a in the cytoplasm. CRISPR/Cas9 mediated knockout of Puma in leukemic cells led to an increased drug resistance in the knockout cells demonstrating a direct role in TKI resistance. Since Puma promotes cell death by targeting Bcl2, TKI-resistant cells showed high Bcl2 levels and targeting Bcl2 with Venetoclax (ABT199) led to increased apoptosis in these cells. In vivo treatment of mice xenografted with resistant cells using ABT199 suppressed leukemogenesis and led to prolonged survival. This in-depth survey of the underlying genetic mechanisms of resistance has identified a potential means of treating FGFR1-driven malignancies that are resistant to FGFR1 inhibitors.

scholarly journals Dual Signaling of the Fas Receptor: Initiation of Both Apoptotic and Necrotic Cell Death Pathways

1998 ◽  
Vol 188 (5) ◽  
pp. 919-930 ◽  
Author(s):  
Dominique Vercammen ◽  
Greet Brouckaert ◽  
Geertrui Denecker ◽  
Marc Van de Craen ◽  
Wim Declercq ◽  
...  
Keyword(s):  
Cell Death ◽  
Nuclear Factor Κb ◽  
Oxygen Radical ◽  
Radical Scavenger ◽  
Apoptotic Pathway ◽  
Proteolytic Activation ◽  
Fas Receptor ◽  
Caspase Inhibitors ◽  
Cell Death Pathways ◽  
Induced Apoptosis

Murine L929 fibrosarcoma cells were transfected with the human Fas (APO-1/CD95) receptor, and the role of various caspases in Fas-mediated cell death was assessed. Proteolytic activation of procaspase-3 and -7 was shown by Western analysis. Acetyl-Tyr-Val-Ala-Asp-chloromethylketone and benzyloxycarbonyl-Asp(OMe)-Glu(OMe)-Val-Asp(OMe)-fluoromethylketone, tetrapeptide inhibitors of caspase-1– and caspase-3–like proteases, respectively, failed to block Fas-induced apoptosis. Unexpectedly, the broad-spectrum caspase inhibitors benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone and benzyloxycarbonyl-Asp(OMe)-fluoromethylketone rendered the cells even more sensitive to Fas-mediated cell death, as measured after 18 h incubation. However, when the process was followed microscopically, it became clear that anti-Fas–induced apoptosis of Fas-transfected L929 cells was blocked during the first 3 h, and subsequently the cells died by necrosis. As in tumor necrosis factor (TNF)-induced necrosis, Fas treatment led to accumulation of reactive oxygen radicals, and Fas-mediated necrosis was inhibited by the oxygen radical scavenger butylated hydroxyanisole. However, in contrast to TNF, anti-Fas did not activate the nuclear factor κB under these necrotic conditions. These results demonstrate the existence of two different pathways originating from the Fas receptor, one rapidly leading to apoptosis, and, if this apoptotic pathway is blocked by caspase inhibitors, a second directing the cells to necrosis and involving oxygen radical production.

scholarly journals Diversity of cell death signaling pathways in macrophages upon infection with modified vaccinia virus Ankara (MVA)

2021 ◽  
Vol 12 (11) ◽  
Author(s):  
Lioba Klaas ◽  
Juliane Vier ◽  
Ian E. Gentle ◽  
Georg Häcker ◽  
Susanne Kirschnek
Keyword(s):  
Cell Death ◽  
Vaccinia Virus ◽  
Signaling Pathways ◽  
Target Cells ◽  
Specific Cell ◽  
Substantial Impact ◽  
Cell Death Pathways ◽  
Modified Vaccinia Virus Ankara ◽  
Cell Death Signaling ◽  
Induced Apoptosis

AbstractRegulated cell death frequently occurs upon infection by intracellular pathogens, and extent and regulation is often cell-type-specific. We aimed to identify the cell death-signaling pathways triggered in macrophages by infection with modified vaccinia virus Ankara (MVA), an attenuated strain of vaccinia virus used in vaccination. While most target cells seem to be protected by antiapoptotic proteins encoded in the MVA genome, macrophages die when infected with MVA. We targeted key signaling components of specific cell death-pathways and pattern recognition-pathways using genome editing and small molecule inhibitors in an in vitro murine macrophage differentiation model. Upon infection with MVA, we observed activation of mitochondrial and death-receptor-induced apoptosis-pathways as well as the necroptosis-pathway. Inhibition of individual pathways had a little protective effect but led to compensatory death through the other pathways. In the absence of mitochondrial apoptosis, autocrine/paracrine TNF-mediated apoptosis and, in the absence of caspase-activity, necroptosis occurred. TNF-induction depended on the signaling molecule STING, and MAVS and ZBP1 contributed to MVA-induced apoptosis. The mode of cell death had a substantial impact on the cytokine response of infected cells, indicating that the immunogenicity of a virus may depend not only on its PAMPs but also on its ability to modulate individual modalities of cell death. These findings provide insights into the diversity of cell death-pathways that an infection can trigger in professional immune cells and advance our understanding of the intracellular mechanisms that govern the immune response to a virus.

Capsaicin-induced apoptosis is regulated by endoplasmic reticulum stress- and calpain-mediated mitochondrial cell death pathways

Toxicology ◽  
2009 ◽  
Vol 264 (3) ◽  
pp. 205-214 ◽  
Author(s):  
Mi-Ja Lee ◽  
Keun-Hong Kee ◽  
Chae-Hong Suh ◽  
Sung-Chul Lim ◽  
Seon-Hee Oh
Keyword(s):  
Endoplasmic Reticulum ◽  
Cell Death ◽  
Endoplasmic Reticulum Stress ◽  
Cell Death Pathways ◽  
Induced Apoptosis

scholarly journals Characterization of Puma-Dependent and Puma-Independent Neuronal Cell Death Pathways following Prolonged Proteasomal Inhibition

2010 ◽  
Vol 30 (23) ◽  
pp. 5484-5501 ◽  
Author(s):  
Liam P. Tuffy ◽  
Caoimhín G. Concannon ◽  
Beatrice D'Orsi ◽  
Matthew A. King ◽  
Ina Woods ◽  
...  
Keyword(s):  
Cell Death ◽  
Proteasome Inhibitor ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Nuclear Condensation ◽  
Apoptosis Pathway ◽  
Mitochondrial Apoptosis Pathway ◽  
Cell Death Pathways ◽  
Cell Death Pathway ◽  
Induced Apoptosis

ABSTRACT Proteasomal stress and the accumulation of polyubiquitinated proteins are key features of numerous neurodegenerative disorders. Previously we demonstrated that stabilization of p53 and activation of its target gene, puma (p53-upregulated mediator of apoptosis), mediated proteasome inhibitor-induced apoptosis in cancer cells. Here we demonstrated that Puma also contributed to proteasome inhibitor-induced apoptosis in mouse neocortical neurons. Although protection afforded by puma gene deletion was incomplete, we found little evidence indicating contributions from other proapoptotic BH3-only proteins. Attenuation of bax expression did not further reduce Puma-independent apoptosis, suggesting that pathways other than the mitochondrial apoptosis pathway were activated. Real-time imaging experiments in wild-type and puma-deficient neurons using a fluorescence resonance energy transfer (FRET)-based caspase sensor confirmed the involvement of a second cell death pathway characterized by caspase activation prior to mitochondrial permeabilization and, more prominently, a third, caspase-independent and Puma-independent pathway characterized by rapid cell shrinkage and nuclear condensation. This pathway involved lysosomal permeabilization in the absence of autophagy activation and was sensitive to cathepsin but not autophagy inhibition. Our data demonstrate that proteasomal stress activates distinct cell death pathways in neurons, leading to both caspase-dependent and caspase-independent apoptosis, and demonstrate independent roles for Puma and lysosomal permeabilization in this model.

scholarly journals The actin nucleation factors JMY and WHAMM enable a rapid Arp2/3 complex-mediated intrinsic pathway of apoptosis

PLoS Genetics ◽  
2021 ◽  
Vol 17 (4) ◽  
pp. e1009512
Author(s):  
Virginia L. King ◽  
Nathan K. Leclair ◽  
Alyssa M. Coulter ◽  
Kenneth G. Campellone
Keyword(s):  
Cell Death ◽  
Actin Assembly ◽  
Actin Nucleation ◽  
Caspase Cleavage ◽  
Cellular Processes ◽  
Cell Death Pathways ◽  
Cell Death Pathway ◽  
Dependent Cell ◽  
Family Gene ◽  
Induced Apoptosis

The actin cytoskeleton is a well-known player in most vital cellular processes, but comparably little is understood about how the actin assembly machinery impacts programmed cell death pathways. In the current study, we explored roles for the human Wiskott-Aldrich Syndrome Protein (WASP) family of actin nucleation factors in DNA damage-induced apoptosis. Inactivation of each WASP-family gene revealed that two of them, JMY and WHAMM, are necessary for rapid apoptotic responses. JMY and WHAMM participate in a p53-dependent cell death pathway by enhancing mitochondrial permeabilization, initiator caspase cleavage, and executioner caspase activation. JMY-mediated apoptosis requires actin nucleation via the Arp2/3 complex, and actin filaments are assembled in cytoplasmic territories containing clusters of cytochrome c and active caspase-3. The loss of JMY additionally results in significant changes in gene expression, including upregulation of the WHAMM-interacting G-protein RhoD. Depletion or deletion of RHOD increases cell death, suggesting that RhoD normally contributes to cell survival. These results give rise to a model in which JMY and WHAMM promote intrinsic cell death responses that can be opposed by RhoD.

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