The Novel ALG-2 Target Protein CDIP1 Promotes Cell Death by Interacting with ESCRT-I and VAPA/B

Apoptosis-linked gene 2 (ALG-2, also known as PDCD6) is a member of the penta-EF-hand (PEF) family of Ca2+-binding proteins. The murine gene encoding ALG-2 was originally reported to be an essential gene for apoptosis. However, the role of ALG-2 in cell death pathways has remained elusive. In the present study, we found that cell death-inducing p53 target protein 1 (CDIP1), a pro-apoptotic protein, interacts with ALG-2 in a Ca2+-dependent manner. Co-immunoprecipitation analysis of GFP-fused CDIP1 (GFP-CDIP1) revealed that GFP-CDIP1 associates with tumor susceptibility gene 101 (TSG101), a known target of ALG-2 and a subunit of endosomal sorting complex required for transport-I (ESCRT-I). ESCRT-I is a heterotetrameric complex composed of TSG101, VPS28, VPS37 and MVB12/UBAP1. Of diverse ESCRT-I species originating from four VPS37 isoforms (A, B, C, and D), CDIP1 preferentially associates with ESCRT-I containing VPS37B or VPS37C in part through the adaptor function of ALG-2. Overexpression of GFP-CDIP1 in HEK293 cells caused caspase-3/7-mediated cell death. In addition, the cell death was enhanced by co-expression of ALG-2 and ESCRT-I, indicating that ALG-2 likely promotes CDIP1-induced cell death by promoting the association between CDIP1 and ESCRT-I. We also found that CDIP1 binds to vesicle-associated membrane protein-associated protein (VAP)A and VAPB through the two phenylalanines in an acidic tract (FFAT)-like motif in the C-terminal region of CDIP1, mutations of which resulted in reduction of CDIP1-induced cell death. Therefore, our findings suggest that different expression levels of ALG-2, ESCRT-I subunits, VAPA and VAPB may have an impact on sensitivity of anticancer drugs associated with CDIP1 expression.

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DMPK is a New Candidate Mediator of Tumor Suppressor p53-Dependent Cell Death

Molecules ◽

10.3390/molecules24173175 ◽

2019 ◽

Vol 24 (17) ◽

pp. 3175

Author(s):

Katsuhiko Itoh ◽

Takahiro Ebata ◽

Hiroaki Hirata ◽

Takeru Torii ◽

Wataru Sugimoto ◽

...

Keyword(s):

Dna Damage ◽

Cell Death ◽

Tumor Suppressor ◽

Dependent Manner ◽

Tumor Suppressor P53 ◽

P53 Family ◽

Gene Encoding ◽

Myotonic Dystrophy Protein Kinase ◽

Induced Apoptosis ◽

Actomyosin Contraction

Tumor suppressor p53 plays an integral role in DNA-damage induced apoptosis, a biological process that protects against tumor progression. Cell shape dramatically changes when cells undergo apoptosis, which is associated with actomyosin contraction; however, it remains entirely elusive how p53 regulates actomyosin contraction in response to DNA-damaging agents. To identify a novel p53 regulating gene encoding the modulator of myosin, we conducted DNA microarray analysis. We found that, in response to DNA-damaging agent doxorubicin, expression of myotonic dystrophy protein kinase (DMPK), which is known to upregulate actomyosin contraction, was increased in a p53-dependent manner. The promoter region of DMPK gene contained potential p53-binding sequences and its promoter activity was increased by overexpression of the p53 family protein p73, but, unexpectedly, not of p53. Furthermore, we found that doxorubicin treatment induced p73 expression, which was significantly attenuated by downregulation of p53. These data suggest that p53 induces expression of DMPK through upregulating p73 expression. Overexpression of DMPK promotes contraction of the actomyosin cortex, which leads to formation of membrane blebs, loss of cell adhesion, and concomitant caspase activation. Taken together, our results suggest the existence of p53-p73-DMPK axis which mediates DNA-damage induced actomyosin contraction at the cortex and concomitant cell death.

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Oncogenic signaling inhibits c-FLIPL expression and its non-apoptotic function during ECM-detachment

Scientific Reports ◽

10.1038/s41598-021-97715-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Matyas Abel Tsegaye ◽

Jianping He ◽

Kyle McGeehan ◽

Ireland M. Murphy ◽

Mati Nemera ◽

...

Keyword(s):

Cell Death ◽

Cancer Cells ◽

Protein C ◽

Tumor Tissue ◽

Oncogenic Signaling ◽

Inhibitory Protein ◽

Cell Death Pathways ◽

Apoptotic Protein ◽

Cellular Context ◽

Context Dependent

AbstractInhibition of programmed cell death pathways is frequently observed in cancer cells where it functions to facilitate tumor progression. However, some proteins involved in the regulation of cell death function dichotomously to both promote and inhibit cell death depending on the cellular context. As such, understanding how cell death proteins are regulated in a context-dependent fashion in cancer cells is of utmost importance. We have uncovered evidence that cellular FLICE-like Inhibitory Protein (c-FLIP), a well-known anti-apoptotic protein, is often downregulated in tumor tissue when compared to adjacent normal tissue. These data argue that c-FLIP may have activity distinct from its canonical role in antagonizing cell death. Interestingly, we have discovered that detachment from extracellular matrix (ECM) serves as a signal to elevate c-FLIP transcription and that oncogenic signaling blocks ECM-detachment-induced c-FLIP elevation. In addition, our data reveal that downregulation of c-FLIP promotes luminal filling in mammary acini and that c-FLIP overexpression in cancer cells inhibits colony formation in cells exposed to ECM-detachment. Taken together, our study reveals an unexpected, non-apoptotic role for c-FLIP during ECM-detachment and raises the possibility that c-FLIP may have context-dependent roles during tumorigenesis.

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Positive allosteric modulation of P2X7 promotes apoptotic cell death over lytic cell death responses in macrophages

Cell Death and Disease ◽

10.1038/s41419-019-2110-3 ◽

2019 ◽

Vol 10 (12) ◽

Cited By ~ 7

Author(s):

Stefan Bidula ◽

Kshitija Dhuna ◽

Ray Helliwell ◽

Leanne Stokes

Keyword(s):

Cell Death ◽

Mitochondrial Membrane ◽

Caspase 3 ◽

Allosteric Modulation ◽

Cell Swelling ◽

Dependent Manner ◽

Apoptosis Pathway ◽

Membrane Rupture ◽

Cell Death Pathways ◽

Intrinsic Apoptosis Pathway

AbstractP2X7 is an ATP-gated ion channel that is highly expressed by leukocytes, such as macrophages. Here, P2X7 has been demonstrated to be involved in the regulation of various cell death pathways; including apoptosis, pyroptosis, necrosis, and autophagy. However, cell death induction via P2X7 is complex and is reliant upon the nature of the stimulus, the duration of the stimulus, and the cell type investigated. Previous reports state that high extracellular ATP concentrations promote osmotic lysis, but whether positive allosteric modulation of P2X7 in the presence of lower concentrations of ATP condemns cells to the same fate is unknown. In this study, we compared cell death induced by high ATP concentrations, to cell death induced by compound K, a recently identified and potent positive allosteric modulator of P2X7. Based on our observations, we propose that high ATP concentrations induce early cell swelling, loss of mitochondrial membrane potential, plasma membrane rupture, and LDH release. Conversely, positive allosteric modulation of P2X7 primarily promotes an intrinsic apoptosis pathway. This was characterised by an increase in mitochondrial Ca2+, accelerated production of mitochondrial ROS, loss of mitochondrial membrane permeability in a Bax-dependent manner, the potential involvement of caspase-1, and caspase-3, and significantly accelerated kinetics of caspase-3 activation. This study highlights the ability of positive allosteric modulators to calibrate P2X7-dependent cell death pathways and may have important implications in modulating the antimicrobial immune response and in the resolution of inflammation.

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Identification and Characterization of the Caspase-Mediated Apoptotic Activity of Teucrium mascatense and an Isolated Compound in Human Cancer Cells

Molecules ◽

10.3390/molecules24050977 ◽

2019 ◽

Vol 24 (5) ◽

pp. 977 ◽

Cited By ~ 7

Author(s):

Neena Panicker ◽

Sameera Balhamar ◽

Shaima Akhlaq ◽

Mohammed Qureshi ◽

Tania Rizvi ◽

...

Keyword(s):

Cell Death ◽

Cancer Cells ◽

Apoptotic Cell ◽

Human Cancer ◽

Annexin V ◽

Dependent Manner ◽

Human Cancer Cells ◽

Cell Death Pathways ◽

Proliferative Effect ◽

Mcf 7

Plants of the genus Teucrium (Lamiaceae or Labiatae family) are known historically for their medicinal value. Here, we identify and characterize the anticancer potential of T. mascatense and its active compound, IM60, in human cancer cells. The anti-proliferative effect of a T. mascatense methanol extract and its various fractions were analyzed in MCF-7 and HeLa cells in a dose- and time dependent manner. The dichloromethane fraction (TMDF) was observed to be the most effective with cytotoxicity against a more expanded series of cell lines, including MDA-MB-231. A time and dose-dependent toxicity profile was also observed for IM60; it could induce rapid cell death (within 3 h) in MCF-7 cells. Activation of caspases and PARP, hallmarks of apoptotic cell death pathways, following treatment with TMDF was demonstrated using western blot analysis. Inversion of the phosphatidylserine phospholipid from the inner to the outer membrane was confirmed by annexin V staining that was inhibited by the classical apoptosis inhibitor, Z-VAK-FMK. Changes in cell rounding, shrinkage, and detachment from other cells following treatment with TMDF and IM60 also supported these findings. Finally, the potential of TMDF and IM60 to induce enzymatic activity of caspases was also demonstrated in MCF-7 cells. This study, thus, not only characterizes the anticancer potential of T. mascatense, but also identifies a lead terpenoid, IM60, with the potential to activate anticancer cell death pathways in human cancer cells.

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Inflammasomes, Autophagy, and Cell Death: The Trinity of Innate Host Defense against Intracellular Bacteria

Mediators of Inflammation ◽

10.1155/2019/2471215 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 20

Author(s):

Teresa Krakauer

Keyword(s):

Cell Death ◽

Host Cell ◽

Host Defense ◽

Intracellular Bacteria ◽

Inflammasome Activation ◽

Type I ◽

Dependent Manner ◽

Cell Death Pathways ◽

Host Cell Death ◽

Molecular Patterns

Inflammasome activation is an innate host defense mechanism initiated upon sensing pathogens or danger in the cytosol. Both autophagy and cell death are cell autonomous processes important in development, as well as in host defense against intracellular bacteria. Inflammasome, autophagy, and cell death pathways can be activated by pathogens, pathogen-associated molecular patterns (PAMPs), cell stress, and host-derived damage-associated molecular patterns (DAMPs). Phagocytosis and toll-like receptor (TLR) signaling induce reactive oxygen species (ROS), type I IFN, NFκB activation of proinflammatory cytokines, and the mitogen-activated protein kinase cascade. ROS and IFNγare also prominent inducers of autophagy. Pathogens, PAMPs, and DAMPs activate TLRs and intracellular inflammasomes, inducing apoptotic and inflammatory caspases in a context-dependent manner to promote various forms of cell death to eliminate pathogens. Common downstream signaling molecules of inflammasomes, autophagy, and cell death pathways interact to initiate appropriate measures against pathogens and determine host survival as well as pathological consequences of infection. The integration of inflammasome activation, autophagy, and cell death is central to pathogen clearance. Various pathogens produce virulence factors to control inflammasomes, subvert autophagy, and modulate host cell death in order to evade host defense. This review highlights the interaction of inflammasomes, autophagy, and host cell death pathways in counteractingBurkholderia pseudomallei, the causative agent of melioidosis. Contrasting evasion strategies used byB.pseudomallei,Mycobacterium tuberculosis, andLegionella pneumophilato avoid and dampen these innate immune responses will be discussed.

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Influence of autophagy, apoptosis and their interplay in filaricidal activity of C-cinnamoyl glycosides

Parasitology ◽

10.1017/s0031182019000660 ◽

2019 ◽

Vol 146 (11) ◽

pp. 1451-1461 ◽

Cited By ~ 2

Author(s):

Priya Roy ◽

Anirban Sengupta ◽

Nikhilesh Joardar ◽

Arindam Bhattacharyya ◽

Nimai Chandra Saha ◽

...

Keyword(s):

Cell Death ◽

Decisive Role ◽

Autophagic Flux ◽

Apoptotic Pathway ◽

Setaria Cervi ◽

Cell Death Pathways ◽

Marker Proteins ◽

Apoptotic Protein ◽

Causative Factors

AbstractThe present work aims to explore the mechanism of action of C-cinnamoyl glycoside as an antifilarial agent against the bovine filarial nematode Setaria cervi. Both apoptosis and autophagy programmed cell death pathways play a significant role in parasitic death. The generation of reactive oxygen species, alteration of the level of antioxidant components and disruption of mitochondrial membrane potential may be the causative factors that drive the parasitic death. Monitoring of autophagic flux via the formation of autophagosome and autophagolysosome was detected via CYTO ID dye. The expression profiling of both apoptotic and autophagic marker proteins strongly support the initial findings of these two cell death processes. The increased interaction of pro-autophagic protein Beclin1 with BCL-2 may promote apoptotic pathway by suppressing anti-apoptotic protein BCL-2 from its function. This in turn partially restrains the autophagic pathway by engaging Beclin1 in the complex. But overall positive increment in autophagic flux was observed. Dynamic interaction and regulative balance of these two critical cellular pathways play a decisive role in controlling disease pathogenesis. Therefore, the present experimental work may prosper the chance for C-cinnamoyl glycosides to become a potential antifilarial therapeutic in the upcoming day after detail in vivo study and proper clinical trial.

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Oncogenic signaling inhibits c-FLIP expression and promotes cancer cell survival during ECM-detachment

10.1101/2021.04.19.440544 ◽

2021 ◽

Author(s):

Matyas Abel Tsegaye ◽

Jianping He ◽

Kyle McGeehan ◽

Ireland M. Murphy ◽

Mati Nemera ◽

...

Keyword(s):

Cell Death ◽

Cancer Cells ◽

Protein C ◽

Oncogenic Signaling ◽

Inhibitory Protein ◽

Cell Death Pathways ◽

Apoptotic Protein ◽

Cancer Cell Survival ◽

Cellular Context ◽

Context Dependent

AbstractInhibition of programmed cell death pathways is frequently observed in cancer cells where it functions to facilitate tumor progression. However, some proteins involved in the regulation of cell death function dichotomously to both promote and inhibit cell death depending on the cellular context. As such, understanding how cell death proteins are regulated in a context-dependent fashion in cancer cells is of utmost importance. We have uncovered evidence that cellular FLICE-like Inhibitory Protein (c-FLIP), a well-known anti-apoptotic protein, is often downregulated in tumor tissue when compared to adjacent normal tissue. These data argue that c-FLIP may have activity distinct from its canonical role in antagonizing cell death. Interestingly, we have discovered that detachment from extracellular matrix (ECM) serves as a signal to elevate c-FLIP transcription and that oncogenic signaling blocks ECM-detachment-induced c-FLIP elevation. In addition, our data reveal that downregulation of c-FLIP promotes the survival of ECM-detached cells and that c-FLIP overexpression in cancer cells restricts the viability of cancer cells grown in anchorage-independent conditions. Taken together, our study reveals an unexpected role for c-FLIP in constraining the viability of cancer cells during ECM-detachment and raises the idea that c-FLIP may have context-dependent pro- and anti-cell death roles during tumorigenesis.

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Post-Treatment with Erinacine A, a Derived Diterpenoid of H. erinaceus, Attenuates Neurotoxicity in MPTP Model of Parkinson’s Disease

Antioxidants ◽

10.3390/antiox9020137 ◽

2020 ◽

Vol 9 (2) ◽

pp. 137 ◽

Cited By ~ 1

Author(s):

Kam-Fai Lee ◽

Shui-Yi Tung ◽

Chih-Chuan Teng ◽

Chien-Heng Shen ◽

Meng Chiao Hsieh ◽

...

Keyword(s):

Cell Death ◽

Substantia Nigra ◽

Neuronal Survival ◽

Post Treatment ◽

Signal Molecules ◽

Dependent Manner ◽

Treatment Regimens ◽

Cell Death Pathways ◽

Erinacine A

Hericium erinaceus, a valuable pharmaceutical and edible mushroom, contains potent bioactive compounds such as H. erinaceus mycelium (HEM) and its derived ethanol extraction of erinacine A, which have been found to regulate physiological functions in our previous study. However, HEM or erinacine A with post-treatment regimens also shows effects on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity, but its mechanisms remain unknown. By using annexin-V–fluorescein-isothiocyanate (FITC)/propidium iodide staining and a 2’,7’ –dichlorofluorescin diacetate (DCFDA) staining assay, the cell death, cell viability, and reactive oxygen species (ROS) of 1-methyl-4-phenylpyridinium (MMP+)-treated Neuro-2a (N2a) cells with or without erinacine A addition were measured, respectively. Furthermore, signaling molecules for regulating the p21/GADD45 cell death pathways and PAKalpha, p21 (RAC1) activated kinase 1 (PAK1) survival pathways were also detected in the cells treated with MPP+ and erinacine A by Western blots. In neurotoxic animal models of MPTP induction, the effects of HEM or erinacine A and its mechanism in vivo were determined by measuring the TH-positive cell numbers and the protein level of the substantia nigra through a brain histological examination. Our results demonstrated that post-treatment with erinacine A was capable of preventing the cytotoxicity of neuronal cells and the production of ROS in vitro and in vivo through the neuroprotective mechanism for erinacine A to rescue the neurotoxicity through the disruption of the IRE1α/TRAF2 interaction and the reduction of p21 and GADD45 expression. In addition, erinacine A treatment activated the conserved signaling pathways for neuronal survival via the phosphorylation of PAK1, AKT, LIM domain kinase 2 (LIMK2), extracellular signal-regulated kinases (ERK), and Cofilin. Similar changes in the signal molecules also were found in the substantia nigra of the MPTP, which caused TH+ neuron damage after being treated with erinacine A in the post-treatment regimens in a dose-dependent manner. Taken together, our data indicated a novel mechanism for post-treatment with erinacine A to protect from neurotoxicity through regulating neuronal survival and cell death pathways.

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Achievements and perspectives in yeast acetic acid-induced programmed cell death pathways

Biochemical Society Transactions ◽

10.1042/bst0391538 ◽

2011 ◽

Vol 39 (5) ◽

pp. 1538-1543 ◽

Cited By ~ 28

Author(s):

Nicoletta Guaragnella ◽

Lucia Antonacci ◽

Salvatore Passarella ◽

Ersilia Marra ◽

Sergio Giannattasio

Keyword(s):

Cell Death ◽

Acetic Acid ◽

Programmed Cell Death ◽

Time Course ◽

Reactive Oxygen Species Generation ◽

Yeast Cells ◽

Model Organisms ◽

Dependent Manner ◽

Cell Death Pathways ◽

Cyt C

The use of non-mammalian model organisms, including yeast Saccharomyces cerevisiae, can provide new insights into eukaryotic PCD (programmed cell death) pathways. In the present paper, we report recent achievements in the elucidation of the events leading to PCD that occur as a response to yeast treatment with AA (acetic acid). In particular, ROS (reactive oxygen species) generation, cyt c (cytochrome c) release and mitochondrial function and proteolytic activity will be dealt with as they vary along the AA-PCD time course by using both wild-type and mutant yeast cells. Two AA-PCD pathways are described sharing common features, but distinct from one another with respect to the role of ROS and mitochondria, the former in which YCA1 acts upstream of cyt c release and caspase-like activation in a ROS-dependent manner and the latter in which cyt c release does not occur, but caspase-like activity increases, in a ROS-independent manner.

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Neisseria gonorrhoeae–Induced Inflammatory Pyroptosis in Human Macrophages is Dependent on Intracellular Gonococci and Lipooligosaccharide

Journal of Cell Death ◽

10.1177/1179066017750902 ◽

2018 ◽

Vol 11 ◽

pp. 117906601775090 ◽

Cited By ~ 5

Author(s):

Jessica Leigh Ritter ◽

Caroline Attardo Genco

Keyword(s):

Cell Death ◽

Neisseria Gonorrhoeae ◽

Transmitted Disease ◽

Human Monocyte ◽

Dependent Manner ◽

Human Macrophages ◽

Sexually Transmitted ◽

Cell Death Pathways ◽

Dependent Cell ◽

Obligate Pathogen

Neisseria gonorrhoeae, the human obligate pathogen responsible for the sexually transmitted disease gonorrhea, has evolved several mechanisms to evade the host immune response. One such mechanism is the modulation of host cell death pathways. In this study, we defined cell death pathways induced by N gonorrhoeae in human monocyte-derived macrophages (MDMs). In a dose-dependent manner, N gonorrhoeae stimulation of MDMs resulted in caspase 1 and 4–dependent cell deaths, indicative of canonical and noncanonical pyroptosis, respectively. Internalization of bacteria or stimulation with lipooligosaccharide (LOS) specifically induced pyroptosis in MDMs and increased secretion of IL-1β. Collectively, our results demonstrate that N gonorrhoeae induces inflammatory pyroptosis in human macrophages due in part to intracellular LOS. We propose that this in turn may exacerbate inflammatory outcomes observed during mucosal infection.

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