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 prICE: a downstream target for ceramide-induced apoptosis and for the inhibitory action of Bcl-2

1996 ◽  
Vol 316 (1) ◽  
pp. 25-28 ◽  
Author(s):  
Miriam J. SMYTH ◽  
David K. PERRY ◽  
Jiandi ZHANG ◽  
Guy G. POIRIER ◽  
Yusuf A. HANNUN ◽  
...  
Keyword(s):  
Cell Death ◽  
Inhibitory Action ◽  
Second Messenger ◽  
The Novel ◽  
Over Expression ◽  
Downstream Target ◽  
Induced Apoptosis ◽  
Insight Into

The novel lipid second messenger, ceramide, specifically induced poly(ADP-ribose) polymerase cleavage through activation of the protease prICE. Over-expression of Bcl-2 inhibited ceramide-induced poly(ADP-ribose) polymerase proteolysis and protected cells from ceramide-induced death. These data provide the first insight into the mechanism by which ceramide mediates apoptosis and suggest a mechanism by which Bcl-2 protects from cell death.

scholarly journals Antidepressant Drug Enhanced Trail Receptor-2 Expression and Sensitized Lung Cancer Cells to Trail-Induced Apoptosis via Inhibition of Autophagic Flux

2020 ◽  
Author(s):  
K.M.A. Zinnah ◽  
Jae-Won Seol ◽  
Sang-Youel Park
Keyword(s):  
Lung Cancer ◽  
Cell Death ◽  
Cancer Cells ◽  
Antidepressant Drug ◽  
Lung Cancer Cells ◽  
Autophagic Flux ◽  
Trail Receptor ◽  
Treatment Needs ◽  
Induced Apoptosis ◽  
Autophagy Inhibition

Autophagy, an alternative cell death mechanism, is also termed programmed cell death type II. Autophagy in cancer treatment needs to be regulated. In our study, autophagy inhibition by desipramine or the autophagy inhibitor chloroquine (CQ) enhanced tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor-2 [death receptor (DR5)] expression and subsequently TRAIL-induced apoptosis in TRAIL-resistant A549 lung cancer cells. Genetic inhibition of DR5 substantially reduced desipramine-enhanced TRAIL-mediated apoptosis, proving that DR5 was required to increase TRAIL sensitivity in TRAIL-resistant cancer cells. Desipramine treatment upregulated p62 expression and promoted conversion of light chain 3 (LC3)-I to its lipid-conjugated form, LC3-II, indicating that autophagy inhibition occurred at the final stages of autophagic flux. Transmission electron microscopy analysis showed the presence of condensed autophagosomes, which resulted from the late stages of autophagy inhibition by desipramine. TRAIL, in combination with desipramine or CQ, augmented the expression of apoptosis-related proteins cleaved caspase-8 and cleaved caspase-3. Our results contributed to the understanding of the mechanism underlying the synergistic anti-cancer effect of desipramine and TRAIL and presented a novel mechanism of DR5 upregulation. These findings demonstrated that autophagic flux inhibition by desipramine potentiated TRAIL-induced apoptosis, suggesting that appropriate regulation of autophagy is required for sensitizing TRAIL-resistant cancer cells to TRAIL-mediated apoptosis.

Redistribution of phosphatidylethanolamine and phosphatidylserine precedes reperfusion-induced apoptosis

1998 ◽  
Vol 274 (1) ◽  
pp. H242-H248 ◽  
Author(s):  
Nilanjana Maulik ◽  
Valerian E. Kagan ◽  
Vladimir A. Tyurin ◽  
Dipak K. Das
Keyword(s):  
Cell Death ◽  
Dna Fragmentation ◽  
Genomic Dna ◽  
High Performance ◽  
Apoptotic Cell ◽  
Ischemia Reperfusion ◽  
Apoptotic Cell Death ◽  
Dna Laddering ◽  
Outer Leaflet ◽  
Induced Apoptosis

Although cardiomyocyte death and infarction associated with ischemia-reperfusion are traditionally believed to be induced via necrosis, recent studies implicated apoptotic cell death in ischemic reperfused tissue. To examine whether myocardial ischemic reperfusion injury is mediated by apoptotic cell death, isolated perfused rat hearts were subjected to 15 and 30 min of ischemia as well as 15 min of ischemia followed by 30, 90, or 120 min of reperfusion. At the end of each experiment, hearts were processed for the evaluation of apoptosis and DNA laddering. Apoptosis was studied by visualizing the apoptotic cardiomyocytes by direct fluorescence detection of digoxigenin-labeled genomic DNA using APOPTAG in situ apoptosis detection kit. DNA laddering was evaluated by subjecting the DNA obtained from cardiomyocytes to 1.8% agarose gel electrophoresis and photographed under ultraviolet illumination. In addition, high-performance thin-layer chromatography (HPTLC) of aminophospholipids labeled with 2,4,6-trinitrobenzenesulfonate was performed to evaluate phospholipid topography in cardiomyocytes. The results of our study revealed apoptotic cells only in the 90- and 120-min reperfused hearts as demonstrated by the intense fluorescence of the immunostained digoxigenin-labeled genomic DNA when observed under fluorescence microscope. None of the ischemic hearts showed any evidence of apoptosis. These results corroborated with the findings of DNA fragmentation that showed increased ladders of DNA bands in the 120-min reperfused hearts, representing integer multiples of the internucleosomal DNA length (∼180 bp). Two-dimensional HPTLC of the phospholipids obtained from the cardiomyocytes and transbilayer organization of the phosphatidylethanolamine (PE) and phosphatidylserine (PS) in the myocytes indicated translocation of both PE and PS from the inner leaflet to the outer leaflet of the membrane as early as after 20 min of ischemia. These results demonstrate that the redistribution of PS and PE precedes the apototic cell death and DNA fragmentation associated with the reperfusion of ischemic myocardium, suggesting that ischemia may trigger the signal for apoptosis although it becomes evident during reperfusion.

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.

Oxidative stress interferes with cancer chemotherapy: inhibition of lymphoma cell apoptosis and phagocytosis

Blood ◽  
2000 ◽  
Vol 96 (1) ◽  
pp. 307-313 ◽  
Author(s):  
Emily Shacter ◽  
Joy A. Williams ◽  
Roger M. Hinson ◽  
Sema Sentürker ◽  
Yang-ja Lee
Keyword(s):  
Oxidative Stress ◽  
Cell Death ◽  
Treatment Protocol ◽  
Cell Killing ◽  
Permeability Barrier ◽  
Apoptotic Cells ◽  
Lymphoma Cells ◽  
Chemotherapy Drugs ◽  
Antioxidant Agents ◽  
Induced Apoptosis

Many antineoplastic drugs kill tumor cells by inducing apoptosis. This highly controlled mechanism of cell death is thought to be physiologically advantageous because apoptotic cells are removed by phagocytosis before they lose their permeability barrier, thus preventing induction of an inflammatory response to the dying cells. In contrast, necrotic cells lyse and release their contents into the extracellular space, thus inducing inflammation. In this report, we examine the effects of oxidative stress on chemotherapy-induced cell killing. We find that H2O2 inhibits the ability of 4 different chemotherapy drugs (VP-16, doxorubicin, cisplatin, and AraC) to induce apoptosis in human Burkitt lymphoma cells. H2O2 shifts the form of cell death from apoptosis to pyknosis/necrosis, which occurs after a significant delay compared with chemotherapy-induced apoptosis. It can also lower the degree of cell killing by these drugs. These effects of H2O2 can be prevented by the antioxidant agents Desferal, Tempol, and dimethylsulfoxide. Phagocytosis by monocyte-derived macrophages of VP-16–treated lymphoma cells is also inhibited by H2O2. Cells killed with H2O2 (with or without VP-16) do ultimately undergo phagocytosis, but this occurs only after they have lost their permeability barrier. Thus, membrane-intact apoptotic cells are recognized and phagocytosed by monocyte-derived macrophages, but membrane-intact pyknotic/necrotic cells are not. The results suggest that chemotherapy-induced apoptosis and phagocytosis of cancer cells may be enhanced by including certain antioxidant agents in the treatment protocol.

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 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 Rac1 Inhibits Apoptosis in Human Lymphoma Cells by Stimulating Bad Phosphorylation on Ser-75

2004 ◽  
Vol 24 (14) ◽  
pp. 6205-6214 ◽  
Author(s):  
Baolin Zhang ◽  
Yaqin Zhang ◽  
Emily Shacter
Keyword(s):  
Cell Survival ◽  
Phosphorylation Site ◽  
Small Gtpase ◽  
Lymphoma Cells ◽  
Drug Induced ◽  
Chemotherapy Drugs ◽  
Human Lymphoma ◽  
Induced Apoptosis

ABSTRACT The small GTPase Rac1 has emerged as an important regulator of cell survival and apoptosis, but the mechanisms involved are not completely understood. In this report, constitutively active Rac1 is shown to stimulate the phosphorylation of the Bcl-2 family member Bad, thereby suppressing drug-induced caspase activation and apoptosis in human lymphoma cells. Rac1 activation leads to human Bad phosphorylation specifically at serine-75 (corresponding to murine serine-112) both in vivo and in vitro. Inhibition of constitutive and activated Rac1-induced Bad phosphorylation by a cell-permeable competitive peptide inhibitor representing this Bad phosphorylation site sensitizes lymphoma cells to drug-induced apoptosis. The data show further that endogenous protein kinase A is a primary catalyst of cellular Bad phosphorylation in response to Rac activation, while Akt is not involved. These findings define a mechanism by which active Rac1 promotes lymphoma cell survival and inhibits apoptosis in response to cancer chemotherapy drugs.

scholarly journals Piper sarmentosum induced apoptosis via mitochondrial pathway in human lung adenocarcinoma cells, A549

2016 ◽  
Vol 15 (1) ◽  
Author(s):  
Azila Sirajudeen ◽  
Aisyah Hanani Mohd Tahir ◽  
Radiah Abdul Ghani
Keyword(s):  
Lung Cancer ◽  
Cell Cycle ◽  
Cell Death ◽  
Cytochrome C ◽  
Treatment Strategies ◽  
A549 Cells ◽  
Annexin V ◽  
Mitochondrial Pathway ◽  
Cell Cycle Profile ◽  
Induced Apoptosis

Introduction: Lung cancer has been reported as one of the most common types of cancer worldwide. Current cancer treatments like chemotherapy do not result in a complete cure and are known to cause side effects in the patients. Therefore, alternative treatment strategies are being explored, one of which is to investigate the potential of the local herbs in this regard. Piper sarmentosum (daun kaduk) has received much attention due to its anti-cancer properties in A549 cells. In this study, the cell cycle profile and mechanisms of cell death induced by P. sarmentosum were investigated using a flow cytometer. Methods: The cell cycle profile changes were observed using propidium iodide staining while the type of cell death was analyzed using Annexin-V assay. Caspases -3/7,8 and 9 and cytochrome c assays were elucidated using flow cytometry analysis. Results: P.sarmentosum arrested the growth of A549 cells at G0/G1 phase. The Annexin V analysis revealed that P. sarmentosum exhibited significant induction of apoptosis after 24 h exposure. Caspases analysis showed that P. sarmentosum induced apoptosis through mitochondrial pathway, via the activation of caspase 3 and caspase 9. Meanwhile, cytochrome c analysis revealed that P. sarmentosum induced a mitochondrial pathway of cell death through the release of cytochrome c. Conclusions: Based on these preliminary findings, P. sarmentosum has a great potential as a dietary cancer treatment for lung cancer and may perhaps be used for lung cancer pharmacotherapy in the clinical settings in future.

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