scholarly journals Protection From Apoptosis by Steel Factor But Not Interleukin-3 Is Reversed Through Blockade of Calcium Influx

Blood ◽  
1998 ◽  
Vol 91 (6) ◽  
pp. 1891-1900 ◽  
Author(s):  
Jennifer L. Gommerman ◽  
Stuart A. Berger
Keyword(s):  
Cell Death ◽  
Mast Cells ◽  
Cell Survival ◽  
Calcium Influx ◽  
Caspase Inhibitors ◽  
Steel Factor ◽  
Interleukin 3 ◽  
Kit Receptor ◽  
Induced Apoptosis ◽  
P815 Mastocytoma

Abstract Steel factor (SLF), the ligand for the c-Kit receptor, protects hemopoietic progenitors and mast cells from apoptosis. We show here that protection of 32D-Kit cells or mast cells from apoptosis by SLF is abrogated through concurrent inhibition of Ca2+influx. In contrast, cell survival promoted by interleukin-3 is not affected by Ca2+ influx blockers. In the presence of blockers, increasing stimulation by SLF leads to greater levels of cell death in the population, indicating that it is the combination of activation by SLF with concurrent blockade of Ca2+ influx that results in apoptosis. The p815 mastocytoma, which expresses a mutated, constitutively active c-kit receptor, dies apoptotically in the presence of Ca2+ influx blockers alone. Ionomycin protects cells from SLF plus blocker-induced apoptosis, confirming specificity for Ca2+ ion blockade in cell death induction. Overexpression of bcl-2, which protects 32D-Kit cells from factor withdrawal, does not protect cells from apoptosis by SLF plus blocker. In contrast, caspase inhibitors YVAD-CHO, DEVD-FMK, and Boc-Asp-FMK protect cells from SLF plus blocker-induced death. These observations highlight the importance of SLF-stimulated Ca2+ influx in the protection of cells from apoptosis and demonstrate a new mechanism for inducing bcl-2 insensitive, caspase-dependent apoptosis through the combination of SLF stimulation with Ca2+ influx blockade.

scholarly journals Protection From Apoptosis by Steel Factor But Not Interleukin-3 Is Reversed Through Blockade of Calcium Influx

Blood ◽  
1998 ◽  
Vol 91 (6) ◽  
pp. 1891-1900 ◽  
Author(s):  
Jennifer L. Gommerman ◽  
Stuart A. Berger
Keyword(s):  
Cell Death ◽  
Mast Cells ◽  
Cell Survival ◽  
Calcium Influx ◽  
Caspase Inhibitors ◽  
Steel Factor ◽  
Interleukin 3 ◽  
Kit Receptor ◽  
Induced Apoptosis ◽  
P815 Mastocytoma

Steel factor (SLF), the ligand for the c-Kit receptor, protects hemopoietic progenitors and mast cells from apoptosis. We show here that protection of 32D-Kit cells or mast cells from apoptosis by SLF is abrogated through concurrent inhibition of Ca2+influx. In contrast, cell survival promoted by interleukin-3 is not affected by Ca2+ influx blockers. In the presence of blockers, increasing stimulation by SLF leads to greater levels of cell death in the population, indicating that it is the combination of activation by SLF with concurrent blockade of Ca2+ influx that results in apoptosis. The p815 mastocytoma, which expresses a mutated, constitutively active c-kit receptor, dies apoptotically in the presence of Ca2+ influx blockers alone. Ionomycin protects cells from SLF plus blocker-induced apoptosis, confirming specificity for Ca2+ ion blockade in cell death induction. Overexpression of bcl-2, which protects 32D-Kit cells from factor withdrawal, does not protect cells from apoptosis by SLF plus blocker. In contrast, caspase inhibitors YVAD-CHO, DEVD-FMK, and Boc-Asp-FMK protect cells from SLF plus blocker-induced death. These observations highlight the importance of SLF-stimulated Ca2+ influx in the protection of cells from apoptosis and demonstrate a new mechanism for inducing bcl-2 insensitive, caspase-dependent apoptosis through the combination of SLF stimulation with Ca2+ influx blockade.

Cell death provoked by loss of interleukin-3 signaling is independent of Bad, Bim, and PI3 kinase, but depends in part on Puma

Blood ◽  
2006 ◽  
Vol 108 (5) ◽  
pp. 1461-1468 ◽  
Author(s):  
Paul G. Ekert ◽  
Anissa M. Jabbour ◽  
Anand Manoharan ◽  
Jacki E. Heraud ◽  
Jai Yu ◽  
...  
Keyword(s):  
Cell Death ◽  
Family Members ◽  
Pi3 Kinase ◽  
Minor Role ◽  
Growth And Survival ◽  
Interleukin 3 ◽  
Dependent Cell ◽  
Induced Apoptosis ◽  
A Minor ◽  
Survival Signals

Growth and survival of hematopoietic cells is regulated by growth factors and cytokines, such as interleukin 3 (IL-3). When cytokine is removed, cells dependent on IL-3 kill themselves by a mechanism that is inhibited by overexpression of Bcl-2 and is likely to be mediated by proapoptotic Bcl-2 family members. Bad and Bim are 2 such BH3-only Bcl-2 family members that have been implicated as key initiators in apoptosis following growth factor withdrawal, particularly in IL-3-dependent cells. To test the role of Bad, Bim, and other proapoptotic Bcl-2 family members in IL-3 withdrawal-induced apoptosis, we generated IL-3-dependent cell lines from mice lacking the genes for Bad, Bim, Puma, both Bad and Bim, and both Bax and Bak. Surprisingly, Bad was not required for cell death following IL-3 withdrawal, suggesting changes to phosphorylation of Bad play only a minor role in apoptosis in this system. Deletion of Bim also had no effect, but cells lacking Puma survived and formed colonies when IL-3 was restored. Inhibition of the PI3 kinase pathway promoted apoptosis in the presence or absence of IL-3 and did not require Bad, Bim, or Puma, suggesting IL-3 receptor survival signals and PI3 kinase survival signals are independent.

Altered expression of prostaglandin synthases in NSCLC: Therapeutic strategies and targets for intervention

2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 18083-18083
Author(s):  
M. Cathcart ◽  
K. Gatley ◽  
E. Kay ◽  
G. P. Pidgeon ◽  
K. J. O’ Byrne
Keyword(s):  
Lung Cancer ◽  
Cell Death ◽  
Cell Survival ◽  
Lower Grade ◽  
Altered Expression ◽  
Over Expression ◽  
Chemotherapy Drugs ◽  
Dna Laddering ◽  
Induced Apoptosis ◽  
Brdu Assay

18083 Background: Prostacyclin Synthase (PGIS) and Thromboxane synthase (TXS) metabolize PGH(2) into prostacyclin and thromboxane respectively. PGIS over-expression inhibits cancer growth in a mouse model, while over-expression of TXS caused opposite effects. TXS is expressed in a variety of tumours, associated with poor prognosis and increased metastasis. The aim of this study was to examine the expression of PGIS and TXS in NSCLC, the effect of targeted TXS inhibition, and the mechanisms regulating these effects. Methods: A panel of resected human lung tumours were stained for PGIS and TXS expression by IHC and by western analysis. A 170- core tissue microarray was stained for TXS and intensity correlated with tumour grade. Cell survival was examined by BrdU assay in A-549 (adenocarcinoma) and SKMES-1 (squamous cell carcinoma) cells following 24h selective TXS inhibition with Ozagrel (500nM) alone, or in combination with chemotherapy. Multi-parameter apoptosis signalling was examined after TXS inhibition using In Cell Analyser and confirmed by DNA laddering and cell death ELISA. PCR arrays were used to examine genes involved in tumourigenesis following TXS inhibition. Results: PGIS was absent in lung cancer sections. TXS was over-expressed in lung cancer relative to matched normal, with significantly increased expression in lower grade tumours. PGIS was down-regulated or absent, while TXS expression was up-regulated in tumours v’s normal tissue. Ozagrel significantly reduced cell survival and induced apoptosis, determined by both DNA laddering and Cell Death ELISA. Multi-parameter apoptosis analysis revealed enlarged nuclei, decreased f-actin staining and decreased mitochondrial mass potential, while PCR arrays confirmed upregulation of the pro-apoptotic gene BAX following TXS inhibition. Ozagrel in combination with Doxorubicin (10nM) showed greatest efficacy compared to a number of other chemotherapy drugs. Conclusions: Expression of PGIS and TXS are altered in NSCLC. Overexpression of TXS may regulate tumour survival as its inhibition induces apoptosis, potentially through upregulation of pro- apoptotic proteins. Targeting TXS, alone or in combination with chemotherapy is a potential therapeutic strategy for the treatment of NSCLC. No significant financial relationships to disclose.

scholarly journals Thrombin inhibits Bim (Bcl-2-interacting mediator of cell death) expression and prevents serum-withdrawal-induced apoptosis via protease-activated receptor 1

2003 ◽  
Vol 375 (1) ◽  
pp. 99-109 ◽  
Author(s):  
Claire J. CHALMERS ◽  
Kathryn BALMANNO ◽  
Kathryn HADFIELD ◽  
Rebecca LEY ◽  
Simon J. COOK
Keyword(s):  
Cell Death ◽  
Cell Survival ◽  
De Novo ◽  
Fibroblast Cell ◽  
Mitogen Activated Protein Kinase ◽  
Serum Withdrawal ◽  
Mitogen Activated Protein ◽  
Protease Activated Receptor 1 ◽  
Induced Apoptosis ◽  
Ccl39 Cells

To investigate the role of thrombin in regulating apoptosis, we have used CCl39 cells, a fibroblast cell line in which thrombin-induced cell proliferation has been extensively studied. Withdrawal of serum from CCl39 cells resulted in a rapid apoptotic response that was completely prevented by the inclusion of thrombin. The protective effect of thrombin was reversed by pertussis toxin, suggesting that cell-survival signalling pathways are activated via a Gi or Go heterotrimeric GTPase. Serum-withdrawal-induced death required de novo gene expression and was preceded by the rapid de novo expression of the pro-apoptotic ‘BH3-only’ protein Bim (Bcl-2-interacting mediator of cell death). Thrombin strongly inhibited the up-regulation of both Bim protein and Bim mRNA. The ability of thrombin to repress Bim expression, and to protect cells from apoptosis, was reversed by U0126, a MEK1/2 [MAPK (mitogen-activated protein kinase) or ERK (extracellular-signal-regulated kinase) 1/2] inhibitor, or LY294002, a phosphoinositide 3′-kinase (PI3K) inhibitor, suggesting that both the Raf→MEK→ERK1/2 and PI3K pathways co-operate to repress Bim and promote cell survival. A PAR1p (protease-activated receptor 1 agonist peptide) was also able to protect cells from serum-withdrawal-induced apoptosis, suggesting that thrombin acts via PAR1 to prevent apoptosis.

Oestrogens as apoptosis regulators in mammalian testis: angels or devils?

2015 ◽  
Vol 17 ◽  
Author(s):  
Sara Correia ◽  
Henrique J. Cardoso ◽  
José E. Cavaco ◽  
Sílvia Socorro
Keyword(s):  
Cell Death ◽  
Germ Cell ◽  
Cell Survival ◽  
Cell Fate ◽  
Germ Line ◽  
Clinical Findings ◽  
Molecular Events ◽  
Mammalian Testis ◽  
Induced Apoptosis ◽  
Available Information

In the mammalian testis, spermatogenesis is a highly coordinated process of germ cell development, which ends with the release of ‘mature’ spermatozoa. The fine regulation of spermatogenesis is strictly dependent on sex steroid hormones, which orchestrate the cellular and molecular events underlying normal development of germ cells. Sex steroids actions also rely on the control of germ cell survival, and the programmed cell death by apoptosis has been indicated as a critical process in regulating the size and quality of the germ line. Recently, oestrogens have emerged as important regulators of germ cell fate. However, the beneficial or detrimental effects of oestrogens in spermatogenesis are controversial, with independent reports arguing for their role as cell survival factors or as apoptosis-inducers. The dual behaviour of oestrogens, shifting from ‘angels to devils’ is supported by the clinical findings of increased oestrogens levels in serum and intratesticular milieu of idiopathic infertile men. This review aims to discuss the available information concerning the role of oestrogens in the control of germ cell death and summarises the signalling mechanisms driven oestrogen-induced apoptosis. The present data represent a valuable basis for the clinical management of hyperoestrogenism-related infertility and provide a rationale for the use of oestrogen-target therapies in male infertility.

Histone Deacetylase Inhibitor SAHA Mediates Epigenetic Silencing of KIT D816V Mutated Systemic Mastocytosis Primary Mast Cells and Selective Apoptosis of Mutated Mast Cells

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2834-2834 ◽  
Author(s):  
Hani Abdulkadir ◽  
Jennine Grootens ◽  
Matilda Kjellander ◽  
Eva Hellstrom Lindberg ◽  
Gunnar Nilsson ◽  
...  
Keyword(s):  
Cell Death ◽  
Mast Cell ◽  
Mast Cells ◽  
Histone Deacetylase ◽  
Histone Deacetylase Inhibitors ◽  
Conflicts Of Interest ◽  
Systemic Mastocytosis ◽  
Specific Treatment ◽  
Epigenetic Silencing ◽  
Kit Receptor

Abstract Systemic mastocytosis (SM) is a myeloproliferative disease for which there is currently no specific therapy. Over 90% of the patients carry the D816V point mutation that renders the KIT receptor constitutively active. In the current study, we assessed the sensitivity of mast cell line HMC1.2 and primary SM patient mast cells to histone deacetylase inhibitors, and found that SAHA is most efficient. SAHA induced a rapid downregulation of KIT mRNA, with a subsequent reduction in total KIT protein as well as cell surface KIT. This was followed by major mast cell apoptosis. Primary SM patient mast cells cultured ex vivo were even more sensitive to SAHA than HMC1.2 cells, whereas healthy subject mast cells were unaffected. There was a correlation between cell death and SM disease severity, where cell death was more pronounced in the case of aggressive disease, with almost 100% cell death among mast cells from the mast cell leukemia patient. Using ChIP qPCR, we found that the level of active chromatin mark H3K18ac/totalH3 decreased significantly in the KIT region, due to an increase in H3 density. This epigenetic silencing was specific to the KIT region and not seen in control genes upstream and downstream of KIT. Primary analysis of ChIP-seq data for histone marks H3K4me3 and H3K27me3, demonstrates a downregulation of transcription factors involved in activation of KIT receptor, such as MAPK, for the SAHA treated samples. This indicates an indirect epigenetic silencing of KIT. Our results therefore demonstrate that SAHA epigenetically silences KIT, and work is ongoing to elucidate the exact mechanisms of KIT regulation. Altogether, SAHA maybe a specific treatment for SM. Disclosures No relevant conflicts of interest to declare.

scholarly journals Two Faces of Protein Kinase Cδ: The Contrasting Roles of PKCδ in Cell Survival and Cell Death

2010 ◽  
Vol 10 ◽  
pp. 2272-2284 ◽  
Author(s):  
Alakananda Basu ◽  
Deepanwita Pal
Keyword(s):  
Cell Death ◽  
Protein Kinase ◽  
Cell Survival ◽  
Caspase 3 ◽  
Critical Role ◽  
Tumor Promotion ◽  
Cellular Processes ◽  
Proapoptotic Protein ◽  
Induced Apoptosis ◽  
Protein Kinase Cδ

Protein kinase Cδ (PKCδ) is a member of the PKC family that plays a critical role in the regulation of various cellular processes, including cell proliferation, cell death, and tumor promotion. Since the identification that PKCδ is a substrate for caspase-3, there has been overwhelming literature that linked PKCδ with proapoptotic signaling. While PKCδ generally functions as a proapoptotic protein during DNA damage-induced apoptosis, it can act as an antiapoptotic protein during receptor-initiated cell death. PKCδ has also been implicated in tumor suppression as well as survival of several cancers. The function of PKCδ depends on various factors, including its localization, tyrosine phosphorylation, and the presence of other pro- and antiapoptoic signaling molecules. This review discusses the current literature on the contrasting roles of PKCδ in cell survival and cell death.

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.

Matrix Metalloproteinase-9 Production, a Newly Identified Function of Mast Cell Progenitors, Is Downregulated by c-kit Receptor Activation

Blood ◽  
1999 ◽  
Vol 94 (7) ◽  
pp. 2390-2395 ◽  
Author(s):  
Akane Tanaka ◽  
Katsuhiko Arai ◽  
Yukihiko Kitamura ◽  
Hiroshi Matsuda
Keyword(s):  
Mast Cell ◽  
Stem Cell ◽  
Mast Cells ◽  
Matrix Metalloproteinase ◽  
Stem Cell Factor ◽  
Receptor Activation ◽  
Interleukin 3 ◽  
Kit Receptor ◽  
Kit Gene ◽  
Metalloproteinase 9

Mast cell precursors invade from the peripheral blood into local tissues where they differentiate to their mature phenotypes. However, the mechanism of this migration process has been unclear. We clearly demonstrated here the production and release of matrix metalloproteinase-9 (MMP-9), a matrix-degrading enzyme necessary for leukocyte transmigration, by interleukin-3–dependent mouse mast cell progenitors: bone marrow-derived cultured mast cells and IC-2 mast cells. Because several interleukin-3–independent mast cell lines with active mutations in the c-kit gene did not release MMP-9, the possible involvement of c-kit receptor activation in downregulation of MMP-9 production was predicted. c-kitreceptor activation by stem cell factor led to a significant decrease in MMP-9 production of cultured mast cells and IC-2 mast cells transfected with the c-kit gene. Thus, the present results suggest that mast cell precursors are able to produce MMP-9, which may be essential for mast cell migration into tissues, and that stem cell factor may downregulate the MMP-9 production, resulting in engagement of mast cells to matrix components.

scholarly journals Apoptosis Suppression by Raf-1 and MEK1 Requires MEK- and Phosphatidylinositol 3-Kinase-Dependent Signals

2001 ◽  
Vol 21 (7) ◽  
pp. 2324-2336 ◽  
Author(s):  
Alexander von Gise ◽  
Petra Lorenz ◽  
Claudia Wellbrock ◽  
Brian Hemmings ◽  
Friederike Berberich-Siebelt ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Survival ◽  
Cell Line ◽  
Active Form ◽  
Dominant Negative ◽  
Phosphatidylinositol 3 Kinase ◽  
Interleukin 3 ◽  
Survival Signaling ◽  
Phosphatidylinositol 3 ◽  
Constitutively Active

ABSTRACT Two Ras effector pathways leading to the activation of Raf-1 and phosphatidylinositol 3-kinase (PI3K) have been implicated in the survival signaling by the interleukin 3 (IL-3) receptor. Analysis of apoptosis suppression by Raf-1 demonstrated the requirement for mitochondrial translocation of the kinase in this process. This could be achieved either by overexpression of the antiapoptotic protein Bcl-2 or by targeting Raf-1 to the mitochondria via fusion to the mitochondrial protein Mas p70. Mitochondrially active Raf-1 is unable to activate extracellular signal-related kinase 1 (ERK1) and ERK2 but suppresses cell death by inactivating the proapoptotic Bcl-2 family member BAD. However, genetic and biochemical data also have suggested a role for the Raf-1 effector module MEK-ERK in apoptosis suppression. We thus tested for MEK requirement in cell survival signaling using the interleukin 3 (IL-3)-dependent cell line 32D. MEK is essential for survival and growth in the presence of IL-3. Upon growth factor withdrawal the expression of constitutively active MEK1 mutants significantly delays the onset of apoptosis, whereas the presence of a dominant negative mutant accelerates cell death. Survival signaling by MEK most likely results from the activation of ERKs since expression of a constitutively active form of ERK2 was as effective in protecting NIH 3T3 fibroblasts against doxorubicin-induced cell death as oncogenic MEK. The survival effect of activated MEK in 32D cells is achieved by both MEK- and PI3K-dependent mechanisms and results in the activation of PI3K and in the phosphorylation of AKT. MEK and PI3K dependence is also observed in 32D cells protected from apoptosis by oncogenic Raf-1. Additionally, we also could extend these findings to the IL-3-dependent pro-B-cell line BaF3, suggesting that recruitment of MEK is a common mechanism for survival signaling by activated Raf. Requirement for the PI3K effector AKT in this process is further demonstrated by the inhibitory effect of a dominant negative AKT mutant on Raf-1-induced cell survival. Moreover, a constitutively active form of AKT synergizes with Raf-1 in apoptosis suppression. In summary these data strongly suggest a Raf effector pathway for cell survival that is mediated by MEK and AKT.

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