Non-Canonical Cell Death Induced by p53

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Atul Ranjan

2016-12-01

Full Text Available Programmed cell death is a vital biological process for multicellular organisms to maintain cellular homeostasis, which is regulated in a complex manner. Over the past several years, apart from apoptosis, which is the principal mechanism of caspase-dependent cell death, research on non-apoptotic forms of programmed cell death has gained momentum. p53 is a well characterized tumor suppressor that controls cell proliferation and apoptosis and has also been linked to non-apoptotic, non-canonical cell death mechanisms. p53 impacts these non-canonical forms of cell death through transcriptional regulation of its downstream targets, as well as direct interactions with key players involved in these mechanisms, in a cell type- or tissue context-dependent manner. In this review article, we summarize and discuss the involvement of p53 in several non-canonical modes of cell death, including caspase-independent apoptosis (CIA, ferroptosis, necroptosis, autophagic cell death, mitotic catastrophe, paraptosis, and pyroptosis, as well as its role in efferocytosis which is the process of clearing dead or dying cells.

Apoptotic effects of non-edible parts of Punica granatum on human multiple myeloma cells.

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Kiraz, Yağmur; Neergheen-Bhujun, Vidushi S; Rummun, Nawraj; Baran, Yusuf

2016-02-01

Multiple myeloma is of great concern since existing therapies are unable to cure this clinical condition. Alternative therapeutic approaches are mandatory, and the use of plant extracts is considered interesting. Punica granatum and its derived products were suggested as potential anticancer agents due to the presence of bioactive compounds. Thus, polypenolic-rich extracts of the non-edible parts of P. granatum were investigated for their antiproliferative and apoptotic effects on U266 multiple myeloma cells. We demonstrated that there were dose-dependent decreases in the proliferation of U266 cells in response to P. granatum extracts. Also, exposure to the extracts triggered apoptosis with significant increases in loss of mitochondrial membrane potential in U266 cells exposed to the leaves and stem extracts, while the flower extract resulted in slight increases in loss of MMP. These results were confirmed by Annexin-V analysis. These results documented the cytotoxic and apoptotic effects of P. granatum extracts on human U266 multiple myeloma cells via disruption of mitochondrial membrane potential and increasing cell cycle arrest. The data suggest that the extracts can be envisaged in cancer chemoprevention and call for further exploration into the potential application of these plant parts.

A chalcone-related small molecule that induces methuosis, a novel form of non-apoptotic cell death, in glioblastoma cells

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Overmeyer, Jean H; Young, Ashley M; Bhanot, Haymanti; Maltese, William A

2011-01-01

Abstract Background Methuosis is a unique form of non-apoptotic cell death triggered by alterations in the trafficking of clathrin-independent endosomes, ultimately leading to extreme vacuolization and rupture of the cell. Results Here we describe a novel chalcone-like molecule, 3-(2-methyl-1H- indol-3-yl)-1-(4-pyridinyl)-2-propen-1-one (MIPP) that induces cell death with the hallmarks of methuosis. MIPP causes rapid accumulation of vacuoles derived from macropinosomes, based on time-lapse mi...

Macrophage Clearance of Apoptotic Cells: A Critical Assessment

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Siamon Gordon

2018-01-01

Full Text Available As the body continues to grow and age, it becomes essential to maintain a balance between living and dying cells. Macrophages and dendritic cells play a central role in discriminating among viable, apoptotic, and necrotic cells, as selective and efficient phagocytes, without inducing inappropriate inflammation or immune responses. A great deal has been learnt concerning clearance receptors for modified and non-self-ligands on potential targets, mediating their eventual uptake, disposal, and replacement. In this essay, we assess current understanding of the phagocytic recognition of apoptotic cells within their tissue environment; we conclude that efferocytosis constitutes a more complex process than simply removal of corpses, with regulatory interactions between the target and effector cells, which determine the outcome of this homeostatic process.

Apoptotic Cells Induced Signaling for Immune Homeostasis in Macrophages and Dendritic Cells

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Uriel Trahtemberg

2017-10-01

Full Text Available Inefficient and abnormal clearance of apoptotic cells (efferocytosis contributes to systemic autoimmune disease in humans and mice, and inefficient chromosomal DNA degradation by DNAse II leads to systemic polyarthritis and a cytokine storm. By contrast, efficient clearance allows immune homeostasis, generally leads to a non-inflammatory state for both macrophages and dendritic cells (DCs, and contributes to maintenance of peripheral tolerance. As many as 3 × 108 cells undergo apoptosis every hour in our bodies, and one of the primary “eat me” signals expressed by apoptotic cells is phosphatidylserine (PtdSer. Apoptotic cells themselves are major contributors to the “anti-inflammatory” nature of the engulfment process, some by secreting thrombospondin-1 (TSP-1 or adenosine monophosphate and possibly other immune modulating “calm-down” signals that interact with macrophages and DCs. Apoptotic cells also produce “find me” and “tolerate me” signals to attract and immune modulate macrophages and DCs that express specific receptors for some of these signals. Neither macrophages nor DCs are uniform, and each cell type may variably express membrane proteins that function as receptors for PtdSer or for opsonins like complement or opsonins that bind to PtdSer, such as protein S and growth arrest-specific 6. Macrophages and DCs also express scavenger receptors, CD36, and integrins that function via bridging molecules such as TSP-1 or milk fat globule-EGF factor 8 protein and that differentially engage in various multi-ligand interactions between apoptotic cells and phagocytes. In this review, we describe the anti-inflammatory and pro-homeostatic nature of apoptotic cell interaction with the immune system. We do not review some forms of immunogenic cell death. We summarize the known apoptotic cell signaling events in macrophages and DCs that are related to toll-like receptors, nuclear factor kappa B, inflammasome, the lipid

Corosolic Acid Induces Non-Apoptotic Cell Death through Generation of Lipid Reactive Oxygen Species Production in Human Renal Carcinoma Caki Cells

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Seon Min Woo

2018-04-01

Full Text Available Corosolic acid is one of the pentacyclic triterpenoids isolated from Lagerstroemia speciose and has been reported to exhibit anti-cancer and anti-proliferative activities in various cancer cells. In the present study, we investigated the molecular mechanisms of corosolic acid in cancer cell death. Corosolic acid induces a decrease of cell viability and an increase of cell cytotoxicity in human renal carcinoma Caki cells. Corosolic acid-induced cell death is not inhibited by apoptosis inhibitor (z-VAD-fmk, a pan-caspase inhibitor, necroptosis inhibitor (necrostatin-1, or ferroptosis inhibitors (ferrostatin-1 and deferoxamine (DFO. Furthermore, corosolic acid significantly induces reactive oxygen species (ROS levels, but antioxidants (N-acetyl-l-cysteine (NAC and trolox do not inhibit corosolic acid-induced cell death. Interestingly, corosolic acid induces lipid oxidation, and α-tocopherol markedly prevents corosolic acid-induced lipid peroxidation and cell death. Anti-chemotherapeutic effects of α-tocopherol are dependent on inhibition of lipid oxidation rather than inhibition of ROS production. In addition, corosolic acid induces non-apoptotic cell death in other renal cancer (ACHN and A498, breast cancer (MDA-MB231, and hepatocellular carcinoma (SK-Hep1 and Huh7 cells, and α-tocopherol markedly inhibits corosolic acid-induced cell death. Therefore, our results suggest that corosolic acid induces non-apoptotic cell death in cancer cells through the increase of lipid peroxidation.

Nanosecond pulsed electric fields induce poly(ADP-ribose) formation and non-apoptotic cell death in HeLa S3 cells

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Morotomi-Yano, Keiko; Akiyama, Hidenori [Institute of Pulsed Power Science, Kumamoto University, Kumamoto 860-8555 (Japan); Yano, Ken-ichi, E-mail: yanoken@kumamoto-u.ac.jp [Priority Organization for Innovation and Excellence, Kumamoto University, Kumamoto 860-8555 (Japan)

2013-08-30

Highlights: •Nanosecond pulsed electric field (nsPEF) is a new and unique means for life sciences. •Apoptosis was induced by nsPEF exposure in Jurkat cells. •No signs of apoptosis were detected in HeLa S3 cells exposed to nsPEFs. •Formation of poly(ADP-ribose) was induced in nsPEF-exposed HeLa S3 cells. •Two distinct modes of cell death were activated by nsPEF in a cell-dependent manner. -- Abstract: Nanosecond pulsed electric fields (nsPEFs) have recently gained attention as effective cancer therapy owing to their potency for cell death induction. Previous studies have shown that apoptosis is a predominant mode of nsPEF-induced cell death in several cell lines, such as Jurkat cells. In this study, we analyzed molecular mechanisms for cell death induced by nsPEFs. When nsPEFs were applied to Jurkat cells, apoptosis was readily induced. Next, we used HeLa S3 cells and analyzed apoptotic events. Contrary to our expectation, nsPEF-exposed HeLa S3 cells exhibited no molecular signs of apoptosis execution. Instead, nsPEFs induced the formation of poly(ADP-ribose) (PAR), a hallmark of necrosis. PAR formation occurred concurrently with a decrease in cell viability, supporting implications of nsPEF-induced PAR formation for cell death. Necrotic PAR formation is known to be catalyzed by poly(ADP-ribose) polymerase-1 (PARP-1), and PARP-1 in apoptotic cells is inactivated by caspase-mediated proteolysis. Consistently, we observed intact and cleaved forms of PARP-1 in nsPEF-exposed and UV-irradiated cells, respectively. Taken together, nsPEFs induce two distinct modes of cell death in a cell type-specific manner, and HeLa S3 cells show PAR-associated non-apoptotic cell death in response to nsPEFs.

Nanosecond pulsed electric fields induce poly(ADP-ribose) formation and non-apoptotic cell death in HeLa S3 cells

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Morotomi-Yano, Keiko; Akiyama, Hidenori; Yano, Ken-ichi

2013-01-01

Highlights: •Nanosecond pulsed electric field (nsPEF) is a new and unique means for life sciences. •Apoptosis was induced by nsPEF exposure in Jurkat cells. •No signs of apoptosis were detected in HeLa S3 cells exposed to nsPEFs. •Formation of poly(ADP-ribose) was induced in nsPEF-exposed HeLa S3 cells. •Two distinct modes of cell death were activated by nsPEF in a cell-dependent manner. -- Abstract: Nanosecond pulsed electric fields (nsPEFs) have recently gained attention as effective cancer therapy owing to their potency for cell death induction. Previous studies have shown that apoptosis is a predominant mode of nsPEF-induced cell death in several cell lines, such as Jurkat cells. In this study, we analyzed molecular mechanisms for cell death induced by nsPEFs. When nsPEFs were applied to Jurkat cells, apoptosis was readily induced. Next, we used HeLa S3 cells and analyzed apoptotic events. Contrary to our expectation, nsPEF-exposed HeLa S3 cells exhibited no molecular signs of apoptosis execution. Instead, nsPEFs induced the formation of poly(ADP-ribose) (PAR), a hallmark of necrosis. PAR formation occurred concurrently with a decrease in cell viability, supporting implications of nsPEF-induced PAR formation for cell death. Necrotic PAR formation is known to be catalyzed by poly(ADP-ribose) polymerase-1 (PARP-1), and PARP-1 in apoptotic cells is inactivated by caspase-mediated proteolysis. Consistently, we observed intact and cleaved forms of PARP-1 in nsPEF-exposed and UV-irradiated cells, respectively. Taken together, nsPEFs induce two distinct modes of cell death in a cell type-specific manner, and HeLa S3 cells show PAR-associated non-apoptotic cell death in response to nsPEFs

Significance of apoptotic cell death after γ-irradiation

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Wu, H.G.; Kim, I.H.; Ha, S.W.; Park, C.I.

2003-01-01

Full text: The objectives of this study are to investigate the significance of apoptotic death compared to total cell death after γ-ray irradiation in human Hand N cancer cell lines and to find out correlation between apoptosis and radiation sensitivity. Materials and Method: Head and neck cancer cell lines (PCI-1, PCI-13, and SNU-1066), leukemia cell line (CCRF-CEM), and fibroblast cell line (LM217) as a normal control were used for this study. Cells were irradiated using Cs-137 animal experiment irradiator. Total cell death was measured by clonogenic assay. Annexin-V staining was used to detect the fraction of apoptotic death. The resulting data was analyzed with two parameters, apoptotic index (AI) and apoptotic fraction(AF). AI is ratio of apoptotic cells to total cells, and AF is ration of apoptotic cell death to mutant frequencytion ex(Number of apoptotic cells) / (Number of total cells counted) AF = {(AI) / (1-survival fraction)} x 100 (%) Results. Surviving fraction at 2 Gy (SF2) were 0.741, 0.544, 0.313, 0.302, and 0.100 for PCI-1, PCI-13, SNU-1066, CCRF-CEM, and LM217 cell lines, respectively. Apoptosis was detected in all cell lines. Apoptotic index reached peak value at 72 hours after irradiation in head and neck cancer cell lines, and that was at 24 hours in CCRF-CEM and LM217. Total cell death increased exponentially with increasing radiation dose from 0 Gy to 8 Gy, but the change was minimal in apoptotic index (Fig. 1.). Apoptotic fractions at 2 Gy were 46%, 48%, 46%, 24%, and 19% and at 6 Gy were 20%, 33%, 35%, 17%, and 20% for PCI-1, PCI-13, SNU-1066, CCRF-CEM, and LM217, respectively. The radioresistant cell lines showed more higher apoptotic fraction at 2 Gy (Table 1.), but there was not such correlation at 6 Gy. Conclusion: All cell lines used in this study showed apoptosis after irradiation, but time course of apoptosis was different from that of leukemia cell line and normal fibroblast cell line. Reproductive cell death was more important

Cell-Centric View of Apoptosis and Apoptotic Cell Death-Inducing Antitumoral Strategies

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Maria Dolores Boyano

2011-03-01

Full Text Available Programmed cell death and especially apoptotic cell death, occurs under physiological conditions and is also desirable under pathological circumstances. However, the more we learn about cellular signaling cascades, the less plausible it becomes to find restricted and well-limited signaling pathways. In this context, an extensive description of pathway-connections is necessary in order to point out the main regulatory molecules as well as to select the most appropriate therapeutic targets. On the other hand, irregularities in programmed cell death pathways often lead to tumor development and cancer-related mortality is projected to continue increasing despite the effort to develop more active and selective antitumoral compounds. In fact, tumor cell plasticity represents a major challenge in chemotherapy and improvement on anticancer therapies seems to rely on appropriate drug combinations. An overview of the current status regarding apoptotic pathways as well as available chemotherapeutic compounds provides a new perspective of possible future anticancer strategies.

Effect of Apoptotic Cell Recognition on Macrophage Polarization and Mycobacterial Persistence

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de Oliveira Fulco, Tatiana; Andrade, Priscila Ribeiro; de Mattos Barbosa, Mayara Garcia; Pinto, Thiago Gomes Toledo; Ferreira, Paula Fernandez; Ferreira, Helen; da Costa Nery, José Augusto; Real, Suzana Côrte; Borges, Valéria Matos; Moraes, Milton Ozório; Sarno, Euzenir Nunes; Sampaio, Elizabeth Pereira

2014-01-01

Intracellular Mycobacterium leprae infection modifies host macrophage programming, creating a protective niche for bacterial survival. The milieu regulating cellular apoptosis in the tissue plays an important role in defining susceptible and/or resistant phenotypes. A higher density of apoptotic cells has been demonstrated in paucibacillary leprosy lesions than in multibacillary ones. However, the effect of apoptotic cell removal on M. leprae-stimulated cells has yet to be fully elucidated. In this study, we investigated whether apoptotic cell removal (efferocytosis) induces different phenotypes in proinflammatory (Mϕ1) and anti-inflammatory (Mϕ2) macrophages in the presence of M. leprae. We stimulated Mϕ1 and Mϕ2 cells with M. leprae in the presence or absence of apoptotic cells and subsequently evaluated the M. leprae uptake, cell phenotype, and cytokine pattern in the supernatants. In the presence of M. leprae and apoptotic cells, Mϕ1 macrophages changed their phenotype to resemble the Mϕ2 phenotype, displaying increased CD163 and SRA-I expression as well as higher phagocytic capacity. Efferocytosis increased M. leprae survival in Mϕ1 cells, accompanied by reduced interleukin-15 (IL-15) and IL-6 levels and increased transforming growth factor beta (TGF-β) and IL-10 secretion. Mϕ1 cells primed with M. leprae in the presence of apoptotic cells induced the secretion of Th2 cytokines IL-4 and IL-13 in autologous T cells compared with cultures stimulated with M. leprae or apoptotic cells alone. Efferocytosis did not alter the Mϕ2 cell phenotype or cytokine secretion profile, except for TGF-β. Based on these data, we suggest that, in paucibacillary leprosy patients, efferocytosis contributes to mycobacterial persistence by increasing the Mϕ2 population and sustaining the infection. PMID:25024361

Apoptotic action of peroxisome proliferator-activated receptor-gamma activation in human non small-cell lung cancer is mediated via proline oxidase-induced reactive oxygen species formation.

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Kim, Ki Young; Ahn, Jin Hee; Cheon, Hyae Gyeong

2007-09-01

Peroxisome proliferator-activated receptor (PPAR)-gamma ligands have been shown to inhibit human lung cancers by inducing apoptosis and differentiation. In the present study, we elucidated the apoptotic mechanism of PPARgamma activation in human lung cancers by using a novel PPARgamma agonist, 1-(trans-methylimino-N-oxy)-6-(2-morpholinoethoxy)-3-phenyl-(1H-indene-2-carboxylic acid ethyl ester (KR-62980), and rosiglitazone. PPARgamma activation selectively inhibited cell viability of non-small-cell lung cancer with little effect on small-cell lung cancer and normal lung cells. The cell death induced by PPARgamma activation presented apoptotic features of oligonucleosomal DNA fragmentation in A549 human non-small-cell lung cancer cell line. Reactive oxygen species (ROS) production was accompanied by increased expression of proline oxidase (POX), a redox enzyme expressed in mitochondria, upon incubation with the agonists. POX RNA interference treatment blocked PPARgamma-induced ROS formation and cytotoxicity, suggesting that POX plays a functional role in apoptosis through ROS formation. The apoptotic effects by the agonists were antagonized by bisphenol A diglycidyl ether, a PPARgamma antagonist, and by knockdown of PPARgamma expression, indicating the involvement of PPARgamma in these actions. The results of the present study suggest that PPARgamma activation induces apoptotic cell death in non-small-cell lung carcinoma mainly through ROS formation via POX induction.

Induction of Non-Apoptotic Cell Death by Activated Ras Requires Inverse Regulation of Rac1 and Arf6

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Bhanot, Haymanti; Young, Ashley M.; Overmeyer, Jean H.; Maltese, William A.

2010-01-01

Methuosis is a unique form of non-apoptotic cell death triggered by alterations in the trafficking of clathrin-independent endosomes, ultimately leading to extreme vacuolization and rupture of the cell. Methuosis can be induced in glioblastoma cells by expression of constitutively active Ras. This study identifies the small GTPases, Rac1 and Arf6, and the Arf6 GTPase-activating-protein, GIT1, as key downstream components of the signaling pathway underlying Ras-induced methuosis. The extent to...

Harnessing Apoptotic Cell Clearance to Treat Autoimmune Arthritis

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Philippe Saas

2017-10-01

Full Text Available Early-stage apoptotic cells possess immunomodulatory properties. Proper apoptotic cell clearance during homeostasis has been shown to limit subsequent immune responses. Based on these observations, early-stage apoptotic cell infusion has been used to prevent unwanted inflammatory responses in different experimental models of autoimmune diseases or transplantation. Moreover, this approach has been shown to be feasible without any toxicity in patients undergoing allogeneic hematopoietic cell transplantation to prevent graft-versus-host disease. However, whether early-stage apoptotic cell infusion can be used to treat ongoing inflammatory disorders has not been reported extensively. Recently, we have provided evidence that early-stage apoptotic cell infusion is able to control, at least transiently, ongoing collagen-induced arthritis. This beneficial therapeutic effect is associated with the modulation of antigen-presenting cell functions mainly of macrophages and plasmacytoid dendritic cells, as well as the induction of collagen-specific regulatory CD4+ T cells (Treg. Furthermore, the efficacy of this approach is not altered by the association with two standard treatments of rheumatoid arthritis (RA, methotrexate and tumor necrosis factor (TNF inhibition. Here, in the light of these observations and recent data of the literature, we discuss the mechanisms of early-stage apoptotic cell infusion and how this therapeutic approach can be transposed to patients with RA.

Immunosuppressive effects of apoptotic cells

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Voll, Reinhard E.; Herrmann, Martin; Roth, Edith A.; Stach, Christian; Kalden, Joachim R.; Girkontaite, Irute

1997-11-01

Apoptotic cell death is important in the development and homeostasis of multicellular organisms and is a highly controlled means of eliminating dangerous, damaged or unnecessary cells without causing an inflammatory response or tissue damage,. We now show that the presence of apoptotic cells during monocyte activation increases their secretion of the anti-inflammatory and immunoregulatory cytokine interleukin 10 (IL-10) and decreases secretion of the proinflammatory cytokines tumour necrosis factor-α (TNF-α), IL-1 and IL-12. This may inhibit inflammation and contribute to impaired cell-mediated immunity in conditions associated with increased apoptosis, such as viral infections, pregnancy, cancer and exposure to radiation.

Surface code—biophysical signals for apoptotic cell clearance

International Nuclear Information System (INIS)

Biermann, Mona; Maueröder, Christian; Brauner, Jan M; Chaurio, Ricardo; Herrmann, Martin; Muñoz, Luis E; Janko, Christina

2013-01-01

Apoptotic cell death and the clearance of dying cells play an important and physiological role in embryonic development and normal tissue turnover. In contrast to necrosis, apoptosis proceeds in an anti-inflammatory manner. It is orchestrated by the timed release and/or exposure of so-called ‘find-me’, ‘eat me’ and ‘tolerate me’ signals. Mononuclear phagocytes are attracted by various ‘find-me’ signals, including proteins, nucleotides, and phospholipids released by the dying cell, whereas the involvement of granulocytes is prevented via ‘stay away’ signals. The exposure of anionic phospholipids like phosphatidylserine (PS) by apoptotic cells on the outer leaflet of the plasma membrane is one of the main ‘eat me’ signals. PS is recognized by a number of innate receptors as well as by soluble bridging molecules on the surface of phagocytes. Importantly, phagocytes are able to discriminate between viable and apoptotic cells both exposing PS. Due to cytoskeleton remodeling PS has a higher lateral mobility on the surfaces of apoptotic cells thereby promoting receptor clustering on the phagocyte. PS not only plays an important role in the engulfment process, but also acts as ‘tolerate me’ signal inducing the release of anti-inflammatory cytokines by phagocytes. An efficient and fast clearance of apoptotic cells is required to prevent secondary necrosis and leakage of intracellular danger signals into the surrounding tissue. Failure or prolongation of the clearance process leads to the release of intracellular antigens into the periphery provoking inflammation and development of systemic inflammatory autoimmune disease like systemic lupus erythematosus. Here we review the current findings concerning apoptosis-inducing pathways, important players of apoptotic cell recognition and clearance as well as the role of membrane remodeling in the engulfment of apoptotic cells by phagocytes. (paper)

Pro- and anti-apoptotic CD95 signaling in T cells

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Janssen Ottmar

2011-04-01

Full Text Available Abstract The TNF receptor superfamily member CD95 (Fas, APO-1, TNFRSF6 is known as the prototypic death receptor in and outside the immune system. In fact, many mechanisms involved in apoptotic signaling cascades were solved by addressing consequences and pathways initiated by CD95 ligation in activated T cells or other "CD95-sensitive" cell populations. As an example, the binding of the inducible CD95 ligand (CD95L to CD95 on activated T lymphocytes results in apoptotic cell death. This activation-induced cell death was implicated in the control of immune cell homeostasis and immune response termination. Over the past years, however, it became evident that CD95 acts as a dual function receptor that also exerts anti-apoptotic effects depending on the cellular context. Early observations of a potential non-apoptotic role of CD95 in the growth control of resting T cells were recently reconsidered and revealed quite unexpected findings regarding the costimulatory capacity of CD95 for primary T cell activation. It turned out that CD95 engagement modulates TCR/CD3-driven signal initiation in a dose-dependent manner. High doses of immobilized CD95 agonists or cellular CD95L almost completely silence T cells by blocking early TCR-induced signaling events. In contrast, under otherwise unchanged conditions, lower amounts of the same agonists dramatically augment TCR/CD3-driven activation and proliferation. In the present overview, we summarize these recent findings with a focus on the costimulatory capacity of CD95 in primary T cells and discuss potential implications for the T cell compartment and the interplay between T cells and CD95L-expressing cells including antigen-presenting cells.

Gingerol sensitizes TRAIL-induced apoptotic cell death of glioblastoma cells

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Lee, Dae-Hee, E-mail: leedneo@gmail.com [Departments of Surgery and Pharmacology and Cell Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA (United States); Kim, Dong-Wook [Department of Microbiology, Immunology, and Cancer Biology, University of VA (United States); Jung, Chang-Hwa [Division of Metabolism and Functionality Research, Korea Food Research Institute (Korea, Republic of); Lee, Yong J. [Departments of Surgery and Pharmacology and Cell Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA (United States); Park, Daeho, E-mail: daehopark@gist.ac.kr [School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

2014-09-15

Glioblastoma multiforme (GBM) is the most lethal and aggressive astrocytoma of primary brain tumors in adults. Although there are many clinical trials to induce the cell death of glioblastoma cells, most glioblastoma cells have been reported to be resistant to TRAIL-induced apoptosis. Here, we showed that gingerol as a major component of ginger can induce TRAIL-mediated apoptosis of glioblastoma. Gingerol increased death receptor (DR) 5 levels in a p53-dependent manner. Furthermore, gingerol decreased the expression level of anti-apoptotic proteins (survivin, c-FLIP, Bcl-2, and XIAP) and increased pro-apoptotic protein, Bax and truncate Bid, by generating reactive oxygen species (ROS). We also found that the sensitizing effects of gingerol in TRAIL-induced cell death were blocked by scavenging ROS or overexpressing anti-apoptotic protein (Bcl-2). Therefore, we showed the functions of gingerol as a sensitizing agent to induce cell death of TRAIL-resistant glioblastoma cells. This study gives rise to the possibility of applying gingerol as an anti-tumor agent that can be used for the purpose of combination treatment with TRAIL in TRAIL-resistant glioblastoma tumor therapy. - Highlights: • Most GBM cells have been reported to be resistant to TRAIL-induced apoptosis. • Gingerol enhances the expression level of anti-apoptotic proteins by ROS. • Gingerol enhances TRAIL-induced apoptosis through actions on the ROS–Bcl2 pathway.

Gingerol sensitizes TRAIL-induced apoptotic cell death of glioblastoma cells

International Nuclear Information System (INIS)

Lee, Dae-Hee; Kim, Dong-Wook; Jung, Chang-Hwa; Lee, Yong J.; Park, Daeho

2014-01-01

Glioblastoma multiforme (GBM) is the most lethal and aggressive astrocytoma of primary brain tumors in adults. Although there are many clinical trials to induce the cell death of glioblastoma cells, most glioblastoma cells have been reported to be resistant to TRAIL-induced apoptosis. Here, we showed that gingerol as a major component of ginger can induce TRAIL-mediated apoptosis of glioblastoma. Gingerol increased death receptor (DR) 5 levels in a p53-dependent manner. Furthermore, gingerol decreased the expression level of anti-apoptotic proteins (survivin, c-FLIP, Bcl-2, and XIAP) and increased pro-apoptotic protein, Bax and truncate Bid, by generating reactive oxygen species (ROS). We also found that the sensitizing effects of gingerol in TRAIL-induced cell death were blocked by scavenging ROS or overexpressing anti-apoptotic protein (Bcl-2). Therefore, we showed the functions of gingerol as a sensitizing agent to induce cell death of TRAIL-resistant glioblastoma cells. This study gives rise to the possibility of applying gingerol as an anti-tumor agent that can be used for the purpose of combination treatment with TRAIL in TRAIL-resistant glioblastoma tumor therapy. - Highlights: • Most GBM cells have been reported to be resistant to TRAIL-induced apoptosis. • Gingerol enhances the expression level of anti-apoptotic proteins by ROS. • Gingerol enhances TRAIL-induced apoptosis through actions on the ROS–Bcl2 pathway

Foveolar cells phagocytose apoptotic neutrophils in chronic active Helicobacter pylori gastritis.

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Caruso, R A; Fedele, F; Di Bella, C; Mazzon, E; Rigoli, L

2012-11-01

The recognition and removal of apoptotic inflammatory cells by tissue macrophages and non-professional phagocytes, in a process called efferocytosis, is required for resolution of inflammation and is actively anti-inflammatory. We have previously demonstrated phagocytosis of apoptotic neutrophils by tumor cells in human gastric carcinoma, but to date, there have been no studies investigating this process in chronic active Helicobacter pylori gastritis. Biopsy specimens from 28 subjects with or without H. pylori infection and active inflammation were examined and graded according to the updated Sydney system. Light microscopy, electron microscopy, and Terminal Deoxynucleotidyltransferase-Mediated UTP End Labeling staining were used to identify apoptosis. H. pylori infection was detected by histology and by molecular assay in 16 out of 28 cases. DNA from paraffin-embedded gastric biopsies was amplified using primers specific for cagA, for the cag "empty site" as well as for the s and m alleles of vacA. The more virulent cagA-positive strains were found in five out of nine patients with chronic active gastritis. The vacA s1/m1 and s2/m1 genotypes were more common in nine patients with chronic active gastritis, while the vacA s2/m2 genotype was more frequent in seven patients with chronic inactive gastritis. Apoptotic neutrophils were also detected within the cytoplasmic vacuoles of the foveolar cells of nine cases with chronic active gastritis. Transmission electron micrographs revealed further apoptotic neutrophils within spacious phagosomes of foveolar cells in a similar manner to those described in late-phase efferocytosis both in vivo and in vitro. These new observations expand the morphological spectrum of gastritis in patients infected with more virulent H. pylori strains, compatible with an anti-inflammatory role for the gastric epithelial cells in their removal of apoptotic neutrophils during active chronic gastritis.

An in vivo root hair assay for determining rates of apoptotic-like programmed cell death in plants

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Hogg Bridget V

2011-12-01

Full Text Available Abstract In Arabidopsis thaliana we demonstrate that dying root hairs provide an easy and rapid in vivo model for the morphological identification of apoptotic-like programmed cell death (AL-PCD in plants. The model described here is transferable between species, can be used to investigate rates of AL-PCD in response to various treatments and to identify modulation of AL-PCD rates in mutant/transgenic plant lines facilitating rapid screening of mutant populations in order to identify genes involved in AL-PCD regulation.

Detection of apoptotic cells in tumour paraffin sections

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Pizem, J.; Coer, A.

2003-01-01

Apoptosis is a distinct form of cell death characterised by specific morphological features and regulated by complex molecular mechanisms. Its deregulation is fundamental for tumour growth and progression and, moreover, anticancer therapies suppress tumour growth mainly by induction of apoptosis. Since the extent of apoptosis in a tumour may have prognostic as well as therapeutic implications, much effort has been invested in developing specific methods that can be routinely used to detect apoptotic cells in archival formalin- fixed paraffin-embedded tissue. Complex molecular pathways are involved in the regulation of apoptosis. Pro-apoptotic signals trigger activation of caspases that specifically cleave target proteins. Cleavage of proteins (caspase substrates) is responsible for morphological changes of apoptotic cells and DNA fragmentation. In the last decade, detection of apoptotic cells in formalin-fixed tumour tissue sections has been based mainly on morphology and characteristic DNA fragmentation. Recently, specific antibodies to activated caspases and cleaved target proteins (including cytokeratin 18, actin and PARP) have been produced that enable accurate detection of apoptosis in paraffin sections. (author)

Developmental programming: impact of prenatal testosterone excess on ovarian cell proliferation and apoptotic factors in sheep.

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Salvetti, Natalia R; Ortega, Hugo H; Veiga-Lopez, Almudena; Padmanabhan, Vasantha

2012-07-01

Prenatal testosterone (T) excess leads to reproductive dysfunctions in sheep, which include increased ovarian follicular recruitment and persistence. To test the hypothesis that follicular disruptions in T sheep stem from changes in the developmental ontogeny of ovarian proliferation and apoptotic factors, pregnant Suffolk sheep were injected twice weekly with T propionate or dihydrotestosterone propionate (DHT; a nonaromatizable androgen) from Days 30 to 90 of gestation. Changes in developmental expression of proliferating cell nuclear antigen (PCNA), BCL2, BAX, activated CASP3, and FAS/FASLG were determined at Fetal Days 90 and 140, 22 wk, 10 mo, and 21 mo of age by immunocytochemisty. Prenatal T treatment induced changes in expression of proliferative and apoptotic markers in a follicle-, age-, and steroid-specific manner. Changes in BAX were evident only during fetal life and PCNA, BCL2, and CASP3 only postnatally. Prenatal T and not DHT increased PCNA and decreased BCL2 in granulosa/theca cells of antral follicles at 10 and 21 mo but decreased CASP3 in granulosa/theca cells of antral follicles at 22 wk (prepubertal) and 10 and 21 mo. Both treatments decreased BAX immunostaining in granulosa cells of Fetal Day 90 primordial/primary follicles. Neither treatment affected FAS expression at any developmental time point in any follicular compartment. Effects on BAX appear to be programmed by androgenic actions and PCNA, BCL2, and CASP3 by estrogenic actions of T. Overall, the findings demonstrate that fetal exposure to excess T disrupts the ovarian proliferation/apoptosis balance, thus providing a basis for the follicular disruptions evidenced in these females.

Detection of apoptotic cells using immunohistochemistry

NARCIS (Netherlands)

Newbold, Andrea; Martin, Ben P.; Cullinane, Carleen; Bots, Michael

2014-01-01

Immunohistochemistry is commonly used to show the presence of apoptotic cells in situ. In this protocol, B-cell lymphoma cells are injected into recipient mice and, on tumor formation, the mice are treated with the apoptosis inducer vorinostat (a histone deacetylase inhibitor). Tumor samples are

Cell shape and organelle modification in apoptotic U937 cells

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MR Montinari

2009-12-01

Full Text Available U937 cells induced to apoptosis, progressively and dramatically modified their cell shape by intense blebbing formation, leading to the production of apoptotic bodies. The blebs evolved with time; milder forms of blebbing involving only a region or just the cortical part of the cytoplasm were observed within the first hour of incubation with puromycin; blebbing involving the whole cell body with very deep constrictions is the most frequent event observed during late times of incubation. The ultrastructural analysis of apoptotic cells revealed characteristic features of nuclear fragmentation (budding and cleavage mode and cytoplasmatic modifications. The cytoplasm of blebs does not contain organelles, such as ribosomes or mitochondria. Scarce presence of endoplasmic reticulum can be observed at the site of bleb detachment. However, blebbing is a dispensable event as evaluated by using inhibitor of actin polymerization. In the present study, the progressive modifications of the nucleus, mitochondria, nuclear fragmentation, cytoplasmic blebs formation and production of apoptotic bodies in U937 monocytic cells induced to apoptosis by puromycin (an inhibitor of protein synthesis were simultaneously analyzed.

Apoptotic Effect of Nigella sativa on Human Lymphoma U937 Cells.

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Arslan, Belkis Atasever; Isik, Fatma Busra; Gur, Hazal; Ozen, Fatih; Catal, Tunc

2017-10-01

Nigella sativa is from botanical Ranunculaceae family and commonly known as black seed. Apoptotic effect of N. sativa and its apoptotic signaling pathways on U937 lymphoma cells are unknown. In this study, we investigated selective cytotoxic and apoptotic effects of N. sativa extract and its apoptotic mechanisms on U937 cells. In addition, we also studied selective cytotoxic activity of thymoquinone that is the most active essential oil of N. sativa . Our results showed that N. sativa extract has selective cytotoxicity and apoptotic effects on U937 cells but not ECV304 control cells. However, thymoquinone had no significant cytotoxicity against on both cells. N. sativa extract increased significantly caspase-3, BAD, and p53 gene expressions in U937 cells. N. sativa may have anticancer drug potential and trigger p53-induced apoptosis in U937 lymphoma cells. This is the first study showing the apoptotic effect of Nigella sativa extract on U937 cells. Abbreviations used: CI: Cytotoxicity index, DMEM: Dulbecco's Modified Eagle Medium, HL: Hodgkin's lymphoma, MTT: 3-(4,5-dimethy lthiazol-2yl)-2,5-diphenyl tetrazolium bromide, RPMI: Roswell Park Memorial Institute medium.

TAM receptors in apoptotic cell clearance, autoimmunity, and cancer.

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Nguyen, Khanh-Quynh; Tsou, Wen-I; Kotenko, Sergei; Birge, Raymond B

2013-08-01

Receptor tyrosine kinases, Tyro-3, Axl and Mer, collectively designated as TAM, are involved in the clearance of apoptotic cells. TAM ligands, Gas6 and Protein S, bind to the surfaces of apoptotic cells, and at the same time, interact directly with TAM expressed on phagocytes, impacting the engulfment and clearance of apoptotic cells and debris. The well-tuned and balanced actions of TAM may affect a variety of human pathologies including autoimmunity, retinal degeneration, and cancer. This article emphasizes some of the emerging findings and mechanistic insights into TAM functions that are clinically relevant and possibly therapeutically targeted.

Kinetics of apoptotic markers in exogeneously induced apoptosis of EL4 cells.

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Jessel, Robert; Haertel, Steffen; Socaciu, Carmen; Tykhonova, Svetlana; Diehl, Horst A

2002-01-01

We investigated the time-dependence of apoptotic events in EL4 cells by monitoring plasma membrane changes in correlation to DNA fragmentation and cell shrinkage. We applied three apoptosis inducers (staurosporine, tubericidine and X-rays) and we looked at various markers to follow the early-to-late apoptotic events: phospholipid translocation (identified through annexin V-fluorescein assay and propidium iodide), lipid package (via merocyanine assay), membrane fluidity and anisotropy (via fluorescent measurements), DNA fragmentation by the fluorescence-labeling test and cell size measurements. The different apoptotic inducers caused different reactions of the cells: staurosporine induced apoptosis most rapidly in a high number of cells, tubercidine triggered apoptosis only in the S phase cells, while X-rays caused a G2/M arrest and subsequently apoptosis. Loss of lipid asymmetry is promptly detectable after one hour of incubation time. The phosphatidylserine translocation, decrease of lipid package and anisotropy, and the increase of membrane fluidity appeared to be based on the same process of lipid asymmetry loss. Therefore, the DNA fragmentation and the cell shrinkage appear to be parallel and independent processes running on different time scales but which are kinetically inter-related. The results indicate different signal steps to apoptosis dependent on inducer characteristics but the kinetics of "early-to-late" apoptosis appears to be a fixed program.

Role of wild-type p53 in apoptotic and non-apoptotic cell death induced by X-irradiation and heat treatment in p53-mutated mouse M10 cells

International Nuclear Information System (INIS)

Ito, Atsushi; Nakano, Hisako; Shinohara, Kunio

2010-01-01

The sensitizing effects of wild-type p53 on X-ray-induced cell death and on heat-induced apoptosis in M10, a radiosensitive and Trp53 (mouse p53 gene)-mutated lymphoma cell line which dies through necrosis by X-irradiation, were investigated using three M10 derived transfectants with wild-type TP53 (human p53 gene). Cell death was determined by colony formation and/or dye exclusion test, and apoptosis was detected as the changes in nuclear morphology by Giemsa staining. Expression of wild-type p53 protein increased radiosensitivity of cell death as determined by both clonogenic and dye exclusion assays. This increase in radiosensitivity was attributable largely to apoptosis induction in addition to a small enhancement of necrosis. Interestingly neither pathway to cell death was accompanied by caspase-3 activation. On the other hand, heat-induced caspase-3 dependent apoptotic cell death without transfection was further increased by the transfection of wild-type p53. In conclusion, the introduction of wild-type p53 enhanced apoptotic cell death by X-rays or heat via different mechanisms that do or do not activate caspase-3, respectively. In addition, p53 also enhanced the X-ray-induced necrosis in M10 cells. (author)

p53 dependent apoptotic cell death induces embryonic malformation in Carassius auratus under chronic hypoxia.

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Paramita Banerjee Sawant

Full Text Available Hypoxia is a global phenomenon affecting recruitment as well as the embryonic development of aquatic fauna. The present study depicts hypoxia induced disruption of the intrinsic pathway of programmed cell death (PCD, leading to embryonic malformation in the goldfish, Carrasius auratus. Constant hypoxia induced the early expression of pro-apoptotic/tumor suppressor p53 and concomitant expression of the cell death molecule, caspase-3, leading to high level of DNA damage and cell death in hypoxic embryos, as compared to normoxic ones. As a result, the former showed delayed 4 and 64 celled stages and a delay in appearance of epiboly stage. Expression of p53 efficiently switched off expression of the anti-apoptotic Bcl-2 during the initial 12 hours post fertilization (hpf and caused embryonic cell death. However, after 12 hours, simultaneous downregulation of p53 and Caspase-3 and exponential increase of Bcl-2, caused uncontrolled cell proliferation and prevented essential programmed cell death (PCD, ultimately resulting in significant (p<0.05 embryonic malformation up to 144 hpf. Evidences suggest that uncontrolled cell proliferation after 12 hpf may have been due to downregulation of p53 abundance, which in turn has an influence on upregulation of anti-apoptotic Bcl-2. Therefore, we have been able to show for the first time and propose that hypoxia induced downregulation of p53 beyond 12 hpf, disrupts PCD and leads to failure in normal differentiation, causing malformation in gold fish embryos.

Apoptotic markers in protozoan parasites

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Fasel Nicolas

2010-11-01

Full Text Available Abstract The execution of the apoptotic death program in metazoans is characterized by a sequence of morphological and biochemical changes that include cell shrinkage, presentation of phosphatidylserine at the cell surface, mitochondrial alterations, chromatin condensation, nuclear fragmentation, membrane blebbing and the formation of apoptotic bodies. Methodologies for measuring apoptosis are based on these markers. Except for membrane blebbing and formation of apoptotic bodies, all other events have been observed in most protozoan parasites undergoing cell death. However, while techniques exist to detect these markers, they are often optimised for metazoan cells and therefore may not pick up subtle differences between the events occurring in unicellular organisms and multi-cellular organisms. In this review we discuss the markers most frequently used to analyze cell death in protozoan parasites, paying special attention to changes in cell morphology, mitochondrial activity, chromatin structure and plasma membrane structure/permeability. Regarding classical regulators/executors of apoptosis, we have reviewed the present knowledge of caspase-like and nuclease activities.

5-Lipoxygenase contributes to PPARγ activation in macrophages in response to apoptotic cells.

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von Knethen, Andreas; Sha, Lisa K; Kuchler, Laura; Heeg, Annika K; Fuhrmann, Dominik; Heide, Heinrich; Wittig, Ilka; Maier, Thorsten J; Steinhilber, Dieter; Brüne, Bernhard

2013-12-01

Macrophage polarization to an anti-inflammatory phenotype upon contact with apoptotic cells is a contributing hallmark to immune suppression during the late phase of sepsis. Although the peroxisome proliferator-activated receptor γ (PPARγ) supports this macrophage phenotype switch, it remains elusive how apoptotic cells activate PPARγ. Assuming that a molecule causing PPARγ activation in macrophages originates in the cell membrane of apoptotic cells we analyzed lipid rafts from apoptotic, necrotic, and living human Jurkat T cells which showed the presence of 5-lipoxygenase (5-LO) in lipid rafts of apoptotic cells only. Incubating macrophages with lipid rafts of apoptotic, but not necrotic or living cells, induced PPAR responsive element (PPRE)-driven mRuby reporter gene expression in RAW 264.7 macrophages stably transduced with a 4xPPRE containing vector. Experiments with lipid rafts of apoptotic murine EL4 T cells revealed similar results. To verify the involvement of 5-LO in activating PPARγ in macrophages, Jurkat T cells were incubated with the 5-LO inhibitor MK-866 prior to induction of apoptosis, which failed to induce mRuby expression. Similar results were obtained with lipid rafts of apoptotic EL4 T cells preexposed to the 5-LO inhibitors zileuton and CJ-13610. Interestingly, Jurkat T cells overexpressing 5-LO failed to activate PPARγ in macrophages, while their 5-LO overexpressing apoptotic counterparts did. Our results suggest that during apoptosis 5-LO gets associated with lipid rafts and synthesizes ligands that in turn stimulate PPARγ in macrophages. © 2013.

The calcimimetic R-568 induces apoptotic cell death in prostate cancer cells

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Cheng Guangming

2009-07-01

Full Text Available Abstract Background Increased serum level of parathyroid hormone (PTH was found in metastatic prostate cancers. Calcimimetic R-568 was reported to reduce PTH expression, to suppress cell proliferation and to induce apoptosis in parathyroid cells. In this study, we investigated the effect of R-568 on cellular survival of prostate cancer cells. Methods Prostate cancer cell lines LNCaP and PC-3 were used in this study. Cellular survival was determined with MTT, trypan blue exclusion and fluorescent Live/Death assays. Western blot assay was utilized to assess apoptotic events induced by R-568 treatment. JC-1 staining was used to evaluate mitochondrial membrane potential. Results In cultured prostate cancer LNCaP and PC-3 cells, R-568 treatment significantly reduced cellular survival in a dose- and time-dependent manner. R-568-induced cell death was an apoptotic event, as evidenced by caspase-3 processing and PARP cleavage, as well as JC-1 color change in mitochondria. Knocking down calcium sensing receptor (CaSR significantly reduced R-568-induced cytotoxicity. Enforced expression of Bcl-xL gene abolished R-568-induced cell death, while loss of Bcl-xL expression led to increased cell death in R-568-treated LNCaP cells,. Conclusion Taken together, our data demonstrated that calcimimetic R-568 triggers an intrinsic mitochondria-related apoptotic pathway, which is dependent on the CaSR and is modulated by Bcl-xL anti-apoptotic pathway.

Terminalia Chebula provides protection against dual modes of necroptotic and apoptotic cell death upon death receptor ligation.

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Lee, Yoonjung; Byun, Hee Sun; Seok, Jeong Ho; Park, Kyeong Ah; Won, Minho; Seo, Wonhyoung; Lee, So-Ra; Kang, Kidong; Sohn, Kyung-Cheol; Lee, Ill Young; Kim, Hyeong-Geug; Son, Chang Gue; Shen, Han-Ming; Hur, Gang Min

2016-04-27

Death receptor (DR) ligation elicits two different modes of cell death (necroptosis and apoptosis) depending on the cellular context. By screening a plant extract library from cells undergoing necroptosis or apoptosis, we identified a water extract of Terminalia chebula (WETC) as a novel and potent dual inhibitor of DR-mediated cell death. Investigation of the underlying mechanisms of its anti-necroptotic and anti-apoptotic action revealed that WETC or its constituents (e.g., gallic acid) protected against tumor necrosis factor-induced necroptosis via the suppression of TNF-induced ROS without affecting the upstream signaling events. Surprisingly, WETC also provided protection against DR-mediated apoptosis by inhibition of the caspase cascade. Furthermore, it activated the autophagy pathway via suppression of mTOR. Of the WETC constituents, punicalagin and geraniin appeared to possess the most potent anti-apoptotic and autophagy activation effect. Importantly, blockage of autophagy with pharmacological inhibitors or genetic silencing of Atg5 selectively abolished the anti-apoptotic function of WETC. These results suggest that WETC protects against dual modes of cell death upon DR ligation. Therefore, WETC might serve as a potential treatment for diseases characterized by aberrantly sensitized apoptotic or non-apoptotic signaling cascades.

Barium inhibits arsenic-mediated apoptotic cell death in human squamous cell carcinoma cells.

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Yajima, Ichiro; Uemura, Noriyuki; Nizam, Saika; Khalequzzaman, Md; Thang, Nguyen D; Kumasaka, Mayuko Y; Akhand, Anwarul A; Shekhar, Hossain U; Nakajima, Tamie; Kato, Masashi

2012-06-01

Our fieldwork showed more than 1 μM (145.1 μg/L) barium in about 3 μM (210.7 μg/L) arsenic-polluted drinking well water (n = 72) in cancer-prone areas in Bangladesh, while the mean concentrations of nine other elements in the water were less than 3 μg/L. The types of cancer include squamous cell carcinomas (SCC). We hypothesized that barium modulates arsenic-mediated biological effects, and we examined the effect of barium (1 μM) on arsenic (3 μM)-mediated apoptotic cell death of human HSC-5 and A431 SCC cells in vitro. Arsenic promoted SCC apoptosis with increased reactive oxygen species (ROS) production and JNK1/2 and caspase-3 activation (apoptotic pathway). In contrast, arsenic also inhibited SCC apoptosis with increased NF-κB activity and X-linked inhibitor of apoptosis protein (XIAP) expression level and decreased JNK activity (antiapoptotic pathway). These results suggest that arsenic bidirectionally promotes apoptotic and antiapoptotic pathways in SCC cells. Interestingly, barium in the presence of arsenic increased NF-κB activity and XIAP expression and decreased JNK activity without affecting ROS production, resulting in the inhibition of the arsenic-mediated apoptotic pathway. Since the anticancer effect of arsenic is mainly dependent on cancer apoptosis, barium-mediated inhibition of arsenic-induced apoptosis may promote progression of SCC in patients in Bangladesh who keep drinking barium and arsenic-polluted water after the development of cancer. Thus, we newly showed that barium in the presence of arsenic might inhibit arsenic-mediated cancer apoptosis with the modulation of the balance between arsenic-mediated promotive and suppressive apoptotic pathways.

Induction of Non-Apoptotic Cell Death by Activated Ras Requires Inverse Regulation of Rac1 and Arf6

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Bhanot, Haymanti; Young, Ashley M.; Overmeyer, Jean H.; Maltese, William A.

2010-01-01

Methuosis is a unique form of non-apoptotic cell death triggered by alterations in the trafficking of clathrin-independent endosomes, ultimately leading to extreme vacuolization and rupture of the cell. Methuosis can be induced in glioblastoma cells by expression of constitutively active Ras. This study identifies the small GTPases, Rac1 and Arf6, and the Arf6 GTPase-activating-protein, GIT1, as key downstream components of the signaling pathway underlying Ras-induced methuosis. The extent to which graded expression of active H-Ras(G12V) triggers cytoplasmic vacuolization correlates with the amount of endogenous Rac1 in the active GTP state. Blocking Rac1 activation with the specific Rac inhibitor, EHT 1864, or co-expression of dominant-negative Rac1(T17N), prevents the accumulation of vacuoles induced by H-Ras(G12V). Coincident with Rac1 activation, H-Ras(G12V) causes a decrease in the amount of active Arf6, a GTPase that functions in recycling of clathrin-independent endosomes. The effect of H-Ras(G12V) on Arf6 is blocked by EHT 1864, indicating that the decrease in Arf6-GTP is directly linked to activation of Rac1. Constitutively active Rac1(G12V) interacts with GIT1 in immunoprecipitation assays. Ablation of GIT1 by shRNA prevents the decrease in active Arf6, inhibits vacuolization, and prevents loss of cell viability in cells expressing Rac1(G12V). Together the results suggest that perturbations of endosome morphology associated with Ras-induced methuosis are due to downstream activation of Rac1, combined with reciprocal inactivation of Arf6. The latter appears to be mediated through Rac1 stimulation of GIT1. Further insights into this pathway could suggest opportunities for induction of methuosis in cancers that are resistant to apoptotic cell death. PMID:20713492

SYTO probes: markers of apoptotic cell demise.

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Wlodkowic, Donald; Skommer, Joanna

2007-10-01

As mechanistic studies on tumor cell death advance towards their ultimate translational goal, there is a need for specific, rapid, and high-throughput analytical tools to detect diverse cell demise modes. Patented DNA-binding SYTO probes, for example, are gaining increasing interest as easy-to-use markers of caspase-dependent apoptotic cell death. They are proving convenient for tracking apoptosis in diverse hematopoietic cell lines and primary tumor samples, and, due to their spectral characteristics, appear to be useful for the development of multiparameter flow cytometry assays. Herein, several protocols for multiparametric assessment of apoptotic events using SYTO probes are provided. There are protocols describing the use of green fluorescent SYTO 16 and red fluorescent SYTO 17 dyes in combination with plasma membrane permeability markers. Another protocol highlights the multiparametric use of SYTO 16 dye in conjunction with the mitochondrial membrane potential sensitive probe, tetramethylrhodamine methyl ester (TMRM), and the plasma membrane permeability marker, 7-aminoactinomycin D (7-AAD).

Non-thermal plasma induces mitochondria-mediated apoptotic signaling pathway via ROS generation in HeLa cells.

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Li, Wei; Yu, K N; Ma, Jie; Shen, Jie; Cheng, Cheng; Zhou, Fangjian; Cai, Zhiming; Han, Wei

2017-11-01

Non-thermal plasma (NTP) has been proposed as a novel therapeutic method for anticancer treatment. Although increasing evidence suggests that NTP selectively induces apoptosis in some types of tumor cells, the molecular mechanisms underlying this phenomenon remain unclear. In this study, we further investigated possible molecular mechanisms for NTP-induced apoptosis of HeLa cells. The results showed that NTP exposure significantly inhibited the growth and viability of HeLa cells. Morphological observation and flow cytometry analysis demonstrated that NTP exposure induced HeLa cell apoptosis. NTP exposure also activated caspase-9 and caspase-3, which subsequently cleaved poly (ADP- ribose) polymerase. Furthermore, NTP exposure suppressed Bcl-2 expression, enhanced Bax expression and translocation to mitochondria, activated mitochondria-mediated apoptotic pathway, followed by the release of cytochrome c. Further studies showed that NTP treatment led to ROS generation, whereas blockade of ROS generation by N-acetyl-l-cysteine (NAC, ROS scavengers) significantly prevented NTP-induced mitochondrial alteration and subsequent apoptosis of HeLa cells via suppressing Bax translocation, cytochrome c and caspase-3 activation. Taken together, our results indicated that NTP exposure induced mitochondria-mediated intrinsic apoptosis of HeLa cells was activated by ROS generation. These findings provide insights to the therapeutic potential and clinical research of NTP as a novel tool in cervical cancer treatment. Copyright © 2017. Published by Elsevier Inc.

The phosphatidylserine receptor has essential functions during embryogenesis but not in apoptotic cell removal

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Hafner Martin

2004-08-01

Full Text Available Abstract Background Phagocytosis of apoptotic cells is fundamental to animal development, immune function and cellular homeostasis. The phosphatidylserine receptor (Ptdsr on phagocytes has been implicated in the recognition and engulfment of apoptotic cells and in anti-inflammatory signaling. To determine the biological function of the phosphatidylserine receptor in vivo, we inactivated the Ptdsr gene in the mouse. Results Ablation of Ptdsr function in mice causes perinatal lethality, growth retardation and a delay in terminal differentiation of the kidney, intestine, liver and lungs during embryogenesis. Moreover, eye development can be severely disturbed, ranging from defects in retinal differentiation to complete unilateral or bilateral absence of eyes. Ptdsr -/- mice with anophthalmia develop novel lesions, with induction of ectopic retinal-pigmented epithelium in nasal cavities. A comprehensive investigation of apoptotic cell clearance in vivo and in vitro demonstrated that engulfment of apoptotic cells was normal in Ptdsr knockout mice, but Ptdsr-deficient macrophages were impaired in pro- and anti-inflammatory cytokine signaling after stimulation with apoptotic cells or with lipopolysaccharide. Conclusion Ptdsr is essential for the development and differentiation of multiple organs during embryogenesis but not for apoptotic cell removal. Ptdsr may thus have a novel, unexpected developmental function as an important differentiation-promoting gene. Moreover, Ptdsr is not required for apoptotic cell clearance by macrophages but seems to be necessary for the regulation of macrophage cytokine responses. These results clearly contradict the current view that the phosphatidylserine receptor primarily functions in apoptotic cell clearance.

Anti-apoptotic peptides protect against radiation-induced cell death

International Nuclear Information System (INIS)

McConnell, Kevin W.; Muenzer, Jared T.; Chang, Kathy C.; Davis, Chris G.; McDunn, Jonathan E.; Coopersmith, Craig M.; Hilliard, Carolyn A.; Hotchkiss, Richard S.; Grigsby, Perry W.; Hunt, Clayton R.

2007-01-01

The risk of terrorist attacks utilizing either nuclear or radiological weapons has raised concerns about the current lack of effective radioprotectants. Here it is demonstrated that the BH4 peptide domain of the anti-apoptotic protein Bcl-xL can be delivered to cells by covalent attachment to the TAT peptide transduction domain (TAT-BH4) and provide protection in vitro and in vivo from radiation-induced apoptotic cell death. Isolated human lymphocytes treated with TAT-BH4 were protected against apoptosis following exposure to 15 Gy radiation. In mice exposed to 5 Gy radiation, TAT-BH4 treatment protected splenocytes and thymocytes from radiation-induced apoptotic cell death. Most importantly, in vivo radiation protection was observed in mice whether TAT-BH4 treatment was given prior to or after irradiation. Thus, by targeting steps within the apoptosis signaling pathway it is possible to develop post-exposure treatments to protect radio-sensitive tissues

Immune responses of dendritic cells after acquiring antigen from apoptotic hepatocholangioma cells caused by γ-ray

International Nuclear Information System (INIS)

Wu Gang; Gu Hongguang; Han Benli; Pei Xuetao

2002-01-01

Objective: To investigate the induction of cytotoxic T lymphocytes (CTLs) in antitumor responsiveness and therapeutic effects after dendritic cells (DCs) acquired antigen from apoptotic hepatocholangioma cells. Methods: DCs from blood mononuclear cells that maintain the characteristics of immaturity-anti-gen-capturing and-processing capacity were established in vitro by using granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin-4. Then, apoptosis in hepatocholangioma cells was induced with γ-radiation. The experimental groups included (1) co-culture of DCs, and apoptotic cancer cells and T cells; (2) co-culture of DCs necrotic cancer cells and T cells; (3) co-culture of DCs-cultured cancer cell and T cells. These cells were co-cultured for 7 days. DCs and T cell were enriched separately. Finally, antitumor response test was carried out. Results: These cells had typical dendritic morphology, expressed high levels of CD1a, B7 and acquired antigen from apoptotic cells caused by γ-rays and induced an increased T cell-stimulatory capacity in MLR. Conclusions: DCs obtained from blood mononuclear cells using GM-CSF and IL-4 and DCs can efficiently present antigen driven from apoptotic cells caused by γ-rays and induce T cells increasing obviously. It can probably become an effective approach of DC transduction with antigen

Proteinase 3 on apoptotic cells disrupts immune silencing in autoimmune vasculitis

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Millet, Arnaud; Martin, Katherine R.; Bonnefoy, Francis; Saas, Philippe; Mocek, Julie; Alkan, Manal; Terrier, Benjamin; Kerstein, Anja; Tamassia, Nicola; Satyanarayanan, Senthil Kumaran; Ariel, Amiram; Ribeil, Jean-Antoine; Guillevin, Loïc; Cassatella, Marco A.; Mueller, Antje; Thieblemont, Nathalie; Lamprecht, Peter; Mouthon, Luc; Perruche, Sylvain; Witko-Sarsat, Véronique

2015-01-01

Granulomatosis with polyangiitis (GPA) is a systemic necrotizing vasculitis that is associated with granulomatous inflammation and the presence of anti-neutrophil cytoplasmic antibodies (ANCAs) directed against proteinase 3 (PR3). We previously determined that PR3 on the surface of apoptotic neutrophils interferes with induction of antiinflammatory mechanisms following phagocytosis of these cells by macrophages. Here, we demonstrate that enzymatically active membrane-associated PR3 on apoptotic cells triggered secretion of inflammatory cytokines, including granulocyte CSF (G-CSF) and chemokines. This response required the IL-1R1/MyD88 signaling pathway and was dependent on the synthesis of NO, as macrophages from animals lacking these pathways did not exhibit a PR3-associated proinflammatory response. The PR3-induced microenvironment facilitated recruitment of inflammatory cells, such as macrophages, plasmacytoid DCs (pDCs), and neutrophils, which were observed in close proximity within granulomatous lesions in the lungs of GPA patients. In different murine models of apoptotic cell injection, the PR3-induced microenvironment instructed pDC-driven Th9/Th2 cell generation. Concomitant injection of anti-PR3 ANCAs with PR3-expressing apoptotic cells induced a Th17 response, revealing a GPA-specific mechanism of immune polarization. Accordingly, circulating CD4+ T cells from GPA patients had a skewed distribution of Th9/Th2/Th17. These results reveal that PR3 disrupts immune silencing associated with clearance of apoptotic neutrophils and provide insight into how PR3 and PR3-targeting ANCAs promote GPA pathophysiology. PMID:26436651

A neurodegenerative disease mutation that accelerates the clearance of apoptotic cells.

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Kao, Aimee W; Eisenhut, Robin J; Martens, Lauren Herl; Nakamura, Ayumi; Huang, Anne; Bagley, Josh A; Zhou, Ping; de Luis, Alberto; Neukomm, Lukas J; Cabello, Juan; Farese, Robert V; Kenyon, Cynthia

2011-03-15

Frontotemporal lobar degeneration is a progressive neurodegenerative syndrome that is the second most common cause of early-onset dementia. Mutations in the progranulin gene are a major cause of familial frontotemporal lobar degeneration [Baker M, et al. (2006) Nature 442:916-919 and Cruts M, et al. (2006) Nature 442:920-924]. Although progranulin is involved in wound healing, inflammation, and tumor growth, its role in the nervous system and the mechanism by which insufficient levels result in neurodegeneration are poorly understood [Eriksen and Mackenzie (2008) J Neurochem 104:287-297]. We have characterized the normal function of progranulin in the nematode Caenorhabditis elegans. We found that mutants lacking pgrn-1 appear grossly normal, but exhibit fewer apoptotic cell corpses during development. This reduction in corpse number is not caused by reduced apoptosis, but instead by more rapid clearance of dying cells. Likewise, we found that macrophages cultured from progranulin KO mice displayed enhanced rates of apoptotic-cell phagocytosis. Although most neurodegenerative diseases are thought to be caused by the toxic effects of aggregated proteins, our findings suggest that susceptibility to neurodegeneration may be increased by a change in the kinetics of programmed cell death. We propose that cells that might otherwise recover from damage or injury are destroyed in progranulin mutants, which in turn facilitates disease progression.

Find-me and eat-me signals in apoptotic cell clearance: progress and conundrums

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2010-01-01

Everyday we turnover billions of cells. The quick, efficient, and immunologically silent disposal of the dying cells requires a coordinated orchestration of multiple steps, through which phagocytes selectively recognize and engulf apoptotic cells. Recent studies have suggested an important role for soluble mediators released by apoptotic cells that attract phagocytes (“find-me” signals). New information has also emerged on multiple receptors that can recognize phosphatidylserine, the key “eat-me” signal exposed on the surface of apoptotic cells. This perspective discusses recent exciting progress, gaps in our understanding, and the conflicting issues that arise from the newly acquired knowledge. PMID:20805564

The Acetone Extract of Sclerocarya birrea (Anacardiaceae) Possesses Antiproliferative and Apoptotic Potential against Human Breast Cancer Cell Lines (MCF-7)

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Tanih, Nicoline Fri; Ndip, Roland Ndip

2013-01-01

Interesting antimicrobial data from the stem bark of Sclerocarya birrea, which support its use in traditional medicine for the treatment of many diseases, have been delineated. The current study was aimed to further study some pharmacological and toxicological properties of the plant to scientifically justify its use. Anticancer activity of water and acetone extracts of S. birrea was evaluated on three different cell lines, HT-29, HeLa, and MCF-7 using the cell titre blue viability assay in 96-well plates. Apoptosis was evaluated using the acridine orange and propidium iodide staining method, while morphological structure of treated cells was examined using SEM. The acetone extract exhibited remarkable antiproliferative activities on MCF-7 cell lines at dose- and time-dependent manners (24 h and 48 h of incubation). The extract also exerted apoptotic programmed cell death in MCF-7 cells with significant effect on the DNA. Morphological examination also displayed apoptotic characteristics in the treated cells, including clumping, condensation, and culminating to budding of the cells to produce membrane-bound fragmentation, as well as formation of apoptotic bodies. The acetone extract of S. birrea possesses antiproliferative and apoptotic potential against MCF-7-treated cells and could be further exploited as a potential lead in anticancer therapy. PMID:23576913

Co-culture of apoptotic breast cancer cells with immature dendritic cells: a novel approach for DC-based vaccination in breast cancer

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Zheng, Jin [Department of Oncology, State Key Discipline of Cell Biology, Xijing Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China); Department of Traditional Chinese and Western Medicine of Oncology, Tangdu Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China); Liu, Qiang [Department of Hematology, Tangdu Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China); Yang, Jiandong [Department of Hepatobiliary Surgery, Xijing Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China); Ren, Qinyou [Department of Traditional Chinese and Western Medicine of Oncology, Tangdu Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China); Cao, Wei [Department of Interventional Radiology, Tangdu Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China); Yang, Jingyue; Yu, Zhaocai [Department of Oncology, State Key Discipline of Cell Biology, Xijing Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China); Yu, Fang [Department of Gastrointestinal Surgery, Xijing Hospital of Digestive Diseases, the Fourth Military Medical University, Xi' an, Shaanxi (China); Wu, Yanlan [Department of Infectious Diseases, Tangdu Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China); Shi, Hengjun [Department of Traditional Chinese and Western Medicine of Oncology, Tangdu Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China); Liu, Wenchao [Department of Oncology, State Key Discipline of Cell Biology, Xijing Hospital, the Fourth Military Medical University, Xi' an, Shaanxi (China)

2012-04-27

A dendritic cell (DC)-based vaccine strategy could reduce the risk of recurrence and improve the survival of breast cancer patients. However, while therapy-induced apoptosis of hepatocellular and colorectal carcinoma cells can enhance maturation and antigen presentation of DCs, whether this effect occurs in breast cancer is currently unknown. In the present study, we investigated the effect of doxorubicin (ADM)-induced apoptotic MCF-7 breast cancer cells on the activation of DCs. ADM-induced apoptotic MCF-7 cells could effectively induce immature DC (iDC) maturation. The mean fluorescence intensity (MFI) of DC maturity marker CD83 was 23.3 in the ADM-induced apoptotic MCF-7 cell group compared with 8.5 in the MCF-7 cell group. The MFI of DC co-stimulatory marker CD86 and HLA-DR were also increased after iDCs were treated with ADM-induced apoptotic MCF-7 cells. Furthermore, the proliferating autologous T-lymphocytes increased from 14.2 to 40.3% after incubated with DCs induced by apoptotic MCF-7 cells. The secretion of interferon-γ by these T-lymphocytes was also increased. In addition, cell-cell interaction between apoptotic MCF-7 cells and iDCs, but not soluble factors released by apoptotic MCF-7 cells, was crucial for the maturation of iDCs. These findings constitute a novel in vitro DC-based vaccine strategy for the treatment of breast cancer by ADM-induced apoptotic MCF-7 cells.

Co-culture of apoptotic breast cancer cells with immature dendritic cells: a novel approach for DC-based vaccination in breast cancer

International Nuclear Information System (INIS)

Zheng, Jin; Liu, Qiang; Yang, Jiandong; Ren, Qinyou; Cao, Wei; Yang, Jingyue; Yu, Zhaocai; Yu, Fang; Wu, Yanlan; Shi, Hengjun; Liu, Wenchao

2012-01-01

A dendritic cell (DC)-based vaccine strategy could reduce the risk of recurrence and improve the survival of breast cancer patients. However, while therapy-induced apoptosis of hepatocellular and colorectal carcinoma cells can enhance maturation and antigen presentation of DCs, whether this effect occurs in breast cancer is currently unknown. In the present study, we investigated the effect of doxorubicin (ADM)-induced apoptotic MCF-7 breast cancer cells on the activation of DCs. ADM-induced apoptotic MCF-7 cells could effectively induce immature DC (iDC) maturation. The mean fluorescence intensity (MFI) of DC maturity marker CD83 was 23.3 in the ADM-induced apoptotic MCF-7 cell group compared with 8.5 in the MCF-7 cell group. The MFI of DC co-stimulatory marker CD86 and HLA-DR were also increased after iDCs were treated with ADM-induced apoptotic MCF-7 cells. Furthermore, the proliferating autologous T-lymphocytes increased from 14.2 to 40.3% after incubated with DCs induced by apoptotic MCF-7 cells. The secretion of interferon-γ by these T-lymphocytes was also increased. In addition, cell-cell interaction between apoptotic MCF-7 cells and iDCs, but not soluble factors released by apoptotic MCF-7 cells, was crucial for the maturation of iDCs. These findings constitute a novel in vitro DC-based vaccine strategy for the treatment of breast cancer by ADM-induced apoptotic MCF-7 cells

Expression of caspase-3 gene in apoptotic HL-60 cell and different human tumor cell lines

International Nuclear Information System (INIS)

Li Xiaoming; Song Tianbao

1999-01-01

Objective: To research the expression of caspase-3 gene in the apoptotic and the control HL-60 cells and in the different human tumor cell lines. Methods: Caspase-3 mRNA in the control and γ-radiation-induced apoptotic HL-60 cells, and in the 6 types of human tumor cell lines, was analysed by Northern blot. Results: The caspase-3 gene transcript was more highly expressed in leukemia cells HL-60, CEM, K562 and neuroblastoma SH-SY5Y than in cervical adenocarcinoma HeLa and breast carcinoma MCF7, and more highly in the radiation-induced apoptotic HL-60 than in the control HL-60 cells. Conclusion: The high level of expression of caspase-3 may aid the efforts to understand the tumor cell sensitivity to radiation, apoptosis and its inherent ability to survive

A Novel Non-Apoptotic Role of Procaspase-3 in the Regulation of Mitochondrial Biogenesis Activators.

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Kim, Ji-Soo; Ha, Ji-Young; Yang, Sol-Ji; Son, Jin H

2018-01-01

The executioner caspase-3 has been proposed as a pharmacological intervention target to preserve degenerating dopaminergic (DA) neurons because apoptotic mechanisms involving caspase-3 contribute, at least in part, to the loss of DA neurons in patients and experimental models of Parkinson's disease (PD). Here, we determined that genetic intervention of caspase-3 was sufficient to prevent cell death against oxidative stress (OS), accompanied by unexpected severe mitochondrial dysfunction. Specifically, as we expected, caspase-3-deficient DA neuronal cells were very significantly resistant to OS-induced cell death, while the activation of the initiator caspase-9 by OS was preserved. Moreover, detailed phenotypic characterization of caspase-3-deficient DA cells revealed severe mitochondrial dysfunction, including an accumulation of damaged mitochondria with a characteristic swollen structure and broken cristae, reduced membrane potential, increased levels of reactive oxygen species (ROS), and deficits in mitochondrial oxidative phosphorylation (OXPHOS) enzymes. Of great interest, we found that mitochondrial biogenesis was dramatically decreased in caspase-3-deficient DA cells, whereas their capability of mitophagy was normal. In accordance with this observation, caspase-3 gene knock down (KD) resulted in dramatically decreased expression of the key transcriptional activators of mitochondrial biogenesis, such as Tfam and Nrf-1, implicating a non-apoptotic role of procaspase-3 in mitochondrial biogenesis. Therefore, a prolonged anti-apoptotic intervention targeting caspase-3 should be considered with caution due to the potential adverse effects in mitochondria dynamics resulting from a novel potential functional role of procaspase-3 in mitochondrial biogenesis via regulating the expression of mitochondrial biogenesis activators. J. Cell. Biochem. 119: 347-357, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Multicolor fluorescence technique to detect apoptotic cells in advanced coronary atherosclerotic plaques

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C Soldani

2009-06-01

Full Text Available Apoptosis occurring in atherosclerotic lesions has been suggested to be involved in the evolution and the structural stability of the plaques. It is still a matter of debate whether apoptosis mainly involves vascular smooth muscle cells (vSMCs in the fibrous tissue or inflammatory (namely foam cells, thus preferentially affecting the cell-poor lipid core of the atherosclerotic plaques. The aim of the present investigation was to detect the presence of apoptotic cells and to estimate their percentage in a series of atherosclerotic plaques obtained either by autopsy or during surgical atherectomy. Apoptotic cells were identified on paraffinembedded sections on the basis of cell nuclear morphology after DNA staining and/or by cytochemical reactions (TUNEL assay, immunodetection of the proteolytic poly (ADP-ribose polymerase-1 [PARP-1] fragment; biochemical procedures (identifying DNA fragmentation or PARP-1 proteolysis were also used. Indirect immunofluorescence techniques were performed to label specific antigens for either vSMCs or macrophages (i.e., the cells which are most likely prone to apoptosis in atherosclerotic lesions: the proper selection of fluorochrome labeling allowed the simultaneous detection of the cell phenotype and the apoptotic characteristics, by multicolor fluorescence techniques. Apoptotic cells proved to be less than 5% of the whole cell population, in atherosclerotic plaque sections: this is, in fact, a too low cell fraction to be detected by widely used biochemical methods, such as agarose gel electrophoresis of low-molecular-weight DNA or Western-blot analysis of PARP-1 degradation. Most apoptotic cells were of macrophage origin, and clustered in the tunica media, near or within the lipid-rich core; only a few TUNEL-positive cells were labeled for antigens specific for vSMCs. These results confirm that, among the cell populations in atherosclerotic plaques, macrophage foam-cells are preferentially involved in apoptosis

The effect of bystander medium on the apoptotic process in HPV-G cells

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Maguire, P.; Lyng, F.; Seymour, C.; Mothersill, C.

2003-01-01

Full text: It has been shown in recent years that in both in vivo and in vitro situations irradiated cells cause what is known as the bystander effect. This presently unknown factor causes chromosomal aberrations, initiation of apoptosis and reduced clonogenic survival. Using the medium transfer method to study the bystander effect, this study investigated early events in the apoptotic cascade, which leads to cell death in cells receiving medium from irradiated cells but which were not themselves irradiated. Medium from irradiated ( 0.005Gy to 5Gy) human HPV G keratinocytes was harvested one hour after irradiation, sterile filtered and transferred on to unirradiated HPV-G cells. The appearance of apoptotic markers in the apoptotic cascade was monitored over a period of 48 hours following medium transfer. These apoptotic markers include loss of mitochondrial membrane potential, cytochrome c release and the activity of the death inducing caspase 3. Clonogenic survival of HPV-G cells over a nine day period was also monitored to assess the final survival of the cells. A TUNEL assay, which indicated the level of apoptosis over a 72 hour period after exposure to bystander medium was also performed. Data collected in this study indicates that for very low doses (0.005Gy) the appearance of well-characterised early 'apoptotic' markers such as changes in mitochondrial membrane potential doesn't mean the cell has committed to the apoptotic cascade leading to cell death. This has been illustrated for bystander medium from 0.005Gy irradiated cells, which causes mitochondrial membrane potential depolarisation after six-hour exposure but little difference has been noted for clonogenic survival for exposure to 0.005Gy bystander medium from that of the control. The results may help clarify how cells sector to death or survival following receipt of a signal from a radiation event

Detection of apoptotic cells using propidium iodide staining

NARCIS (Netherlands)

Newbold, Andrea; Martin, Ben P.; Cullinane, Carleen; Bots, Michael

2014-01-01

Flow cytometry assays are often used to detect apoptotic cells in in vitro cultures. Depending on the experimental model, these assays can also be useful in evaluating apoptosis in vivo. In this protocol, we describe a propidium iodide (PI) flow cytometry assay to evaluate B-cell lymphomas that have

Apoptotic potential and cell sensitivity to fractionated radiotherapy

International Nuclear Information System (INIS)

Rupnow, Brent A.; Murtha, Albert D.; Alarcon, Rodolfo M.; Giaccia, Amato J.; Knox, Susan J.

1997-01-01

Purpose/Objective: At present, the relationship between sensitivity to radiation-induced apoptosis and overall cellular radiosensitivity remains unclear. In particular, the relationship of apoptotic sensitivity to the survival of cells following fractionated irradiation has not been well studied. The purpose of the present study was to determine if increasing cell sensitivity to radiation-induced apoptosis would result in decreased clonogenic survival following single dose and fractionated irradiation in vitro. Materials and Methods: To address this, we chose a cell line (Rat-1MycER) in which the sensitivity to radiation-induced apoptosis could be altered by switching on or off the activity of a conditional c-Myc allele (c-MycER). The c-MycER construct expresses a full length c-Myc protein fused to a modified hormone binding domain of the estrogen receptor. Only in the presence of the estrogen analog 4-hydroxytamoxifen (4HT), does the conditional c-MycER become active. Apoptosis following irradiation in these cells (with and without c-MycER activation) was analyzed by flow cytometry to determine the percentage of cells undergoing apoptosis following various radiation doses and at different times after irradiation. Additionally, clonogenic survival analysis was performed following single radiation doses from 0 to 10 Gy and following five fractions of 2 or 4 Gy each. Survival of cells with and without c-MycER activation was compared. Furthermore, the effect of overexpressing the anti-apoptotic Bcl-2 gene on apoptosis induction and clonogenic survival of these cells was examined. Results: Rat-1MycER cells were strongly sensitized to radiation-induced apoptosis in a dose and time dependent manner when MycER was activated relative to cells treated without c-MycER activation. This c-Myc-mediated sensitivity to radiation-induced apoptosis was suppressed by overexpression of the anti-apoptotic protein Bcl-2. In addition to increasing apoptosis, activating c-MycER prior to

Homeostatic Mass Control in Gastric Non-Neoplastic Epithelia under Infection of Helicobacter pylori: An Immunohistochemical Analysis of Cell Growth, Stem Cells and Programmed Cell Death

International Nuclear Information System (INIS)

Kato, Kenji; Hasui, Kazuhisa; Wang, Jia; Kawano, Yoshifumi; Aikou, Takashi; Murata, Fusayoshi

2008-01-01

We evaluated homeostatic mass control in non-neoplastic gastric epithelia under Helicobacter pylori (HP) infection in the macroscopically normal-appearing mucosa resected from the stomach with gastric cancer, immunohistochemically analyzing the proliferation, kinetics of stem cells and programmed cell death occurring in them. Ki67 antigen-positive proliferating cells were found dominantly in the elongated neck portion, sparsely in the fundic areas and sporadically in the stroma with chronic infiltrates. CD117 could monitor the kinetics of gastric stem cells and showed its expression in two stages of gastric epithelial differentiation, namely, in transient cells from the gastric epithelial stem cells to the foveolar and glandular cells in the neck portion and in what are apparently progenitor cells from the gastric stem cells in the stroma among the infiltrates. Most of the nuclei were positive for ssDNA in the almost normal mucosa, suggesting DNA damage. Cleaved caspase-3-positive foveolar cells were noted under the surface, suggesting the suppression of apoptosis in the surface foveolar cells. Besides such apoptosis of the foveolar cells, in the severely inflamed mucosa apoptotic cells were found in the neck portion where most of the cells were Ki67 antigen-positive proliferating cells. Beclin-1 was recognized in the cytoplasm and in a few nuclei of the fundic glandular cells, suggesting their autophagic cell death and mutated beclin-1 in the nuclei. Taken together, the direct and indirect effects of HP infection on the gastric epithelial proliferation, differentiation and programmed cell death suggested the in-situ occurrence of gastric cancer under HP infection

Cytotoxicity and apoptotic effects of nickel oxide nanoparticles in cultured HeLa cells

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Kezban Ada

2010-04-01

Full Text Available The aim of this study was to observe the cytotoxicity and apoptotic effects of nickel oxide nanoparticles on humancervix epithelioid carcinoma cell line (HeLa. Nickel oxide precursors were synthesized by an nickel sulphate-excess ureareaction in boiling aqueous solution. The synthesized NiO nanoparticles (<200 nm were investigated by X-ray diffractionanalysis and transmission electron microscopy techniques. For cytotoxicity experiments, HeLa cells were incubated in50-500 μg/mL NiO for 2, 6, 12 and 16 hours. The viable cells were counted with a haemacytometer using light microscopy.The cytotoxicity was observed low in 50-200 μg/mL concentration for 16 h, but high in 400-500 μg/mL concentration for2-6 h. HeLa cells' cytoplasm membrane was lysed and detached from the well surface in 400 μg/mL concentration NiOnanoparticles. Double staining and M30 immunostaining were performed to quantify the number of apoptotic cells in cultureon the basis of apoptotic cell nuclei scores. The apoptotic effect was observed 20% for 16 h incubation.

Mitotic and apoptotic activity in colorectal neoplasia.

Science.gov (United States)

Kohoutova, Darina; Pejchal, Jaroslav; Bures, Jan

2018-05-18

Colorectal cancer (CRC) is third most commonly diagnosed cancer worldwide. The aim of the prospective study was to evaluate mitosis and apoptosis of epithelial cells at each stage of colorectal neoplasia. A total of 61 persons were enrolled into the study: 18 patients with non-advanced colorectal adenoma (non-a-A), 13 patients with advanced colorectal adenoma (a-A), 13 patients with CRC and 17 controls: individuals with normal findings on colonoscopy. Biopsy samples were taken from pathology (patients) and healthy mucosa (patients and healthy controls). Samples were formalin-fixed paraffin-embedded and stained with haematoxylin-eosin. Mitotic and apoptotic activity were evaluated in lower and upper part of the crypts and in the superficial compartment. Apoptotic activity was also assessed using detection of activated caspase-3. In controls, mitotic activity was present in lower part of crypts, accompanied with low apoptotic activity. Mitotic and apoptotic activity decreased (to almost zero) in upper part of crypts. In superficial compartment, increase in apoptotic activity was observed. Transformation of healthy mucosa into non-a-A was associated with significant increase of mitotic activity in lower and upper part of the crypts and with significant increase of apoptotic activity in all three compartments; p colorectal neoplasia were observed. Detection of activated caspase-3 confirmed the above findings in apoptotic activity. Significant dysregulation of mitosis and apoptosis during the progression of colorectal neoplasia, corresponding with histology, was confirmed. In patients with sporadic colorectal neoplasia, healthy mucosa does not display different mitotic and apoptotic activity compared to mucosa in healthy controls and therefore adequate endoscopic/surgical removal of colorectal neoplasia is sufficient.

Peroxynitrite decomposition catalyst prevents apoptotic cell death in a human astrocytoma cell line incubated with supernatants of HIV-infected macrophages

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Perno Carlo

2002-09-01

Full Text Available Abstract Background Oxidative stress has shown to contribute in the mechanisms underlying apoptotic cell death occuring in AIDS-dementia complex. Here we investigated the role of peroxynitrite in apoptosis occurring in astroglial cells incubated with supernatants of HIV-infected human primary macrophages (M/M. Results Flow cytometric analysis (FACS of human cultured astrocytes shortly incubated with HIV-1-infected M/M supernatants showed apoptotic cell death, an effect accompanied by pronounced staining for nitrotyrosine (footprint of peroxynitrite and by abnormal formation of malondialdehyde (MDA. Pretreatment of astrocytes with the peroxynitrite decomposition catalyst FeTMPS antagonized HIV-related astrocytic apoptosis, MDA formation and nitrotyrosine staining. Conclusions Taken together, our results suggest that inibition of peroxynitrite leads to protection against peroxidative stress accompanying HIV-related apoptosis of astrocytes. Overall results support the role of peroxynitrite in HIV-related programmed death of astrocytes and suggest the use of peroxynitrite decomposition catalyst to counteract HIV-1-related neurological disorders.

The control and execution of programmed cell death

International Nuclear Information System (INIS)

Begum, R.; Pathak, N.; Hasnain, S.E.; Sah, N.K.; Athar, M.

1999-01-01

Apoptosis or programmed cell death is a highly conserved genetically controlled response of metazoan cells to commit suicide. Non apoptotic programmed cell death seems to operate in single celled eukaryotes implying that evolution of PCD has preceded the evolution of multicellularity. PCD plays a crucial role in the regulation of cellular and tissue homeostasis and any aberrations in apoptosis leads to several diseases including cancer, neurodegenerative disorders and AIDS. The mechanisms by which apoptosis is controlled are varied. In some cells, members of bcl-2 family or p53 are crucial for regulating the apoptosis programme, whereas in other cells Fas ligand is more important. bcl-2 family members have a prime role in the regulation of cell death at all stages including development, whereas cell death during development is independent of p53. bcl-2 family members being localized on the outer mitochondrial membrane, control the mitochondrial homeostasis and cytochrome c redistribution and thereby regulate the cell death process. p53 promotes DNA damage mediated cell death after growth arrest and failed DNA repair. Caspases play a key role in the execution of cell death by mediating highly specific cleavages of crucial cellular proteins collectively manifesting the apoptotic phenotype. Protein inhibitors like crm A, p35 and IAPs could prevent/control apoptosis induced by a broad array of cell death stimuli by several mechanisms specially interfering in caspase activation or caspase activity. Among endonucleases, caspase activated DNase (CAD) plays a crucial role in DNA fragmentation, a biochemical hallmark of apoptosis. As regulation of cell death seems to be as complex as regulation of cell proliferation, multiple kinase mediated regulatory mechanisms might control the apoptotic process. Thus, in spite of intensive research over the past few years, the field of apoptosis still remains fertile to unravel among others, the molecular mechanisms of cytochrome c

The control and execution of programmed cell death

Energy Technology Data Exchange (ETDEWEB)

Begum, R.; Pathak, N.; Hasnain, S.E.; Sah, N.K. [National Inst. of Immunology, New Delhi (India). Eukaryotic Gene Expression Lab.; Taneja, T.K.; Mohan, M. [National Inst. of Immunology, New Delhi (India). Eukaryotic Gene Expression Lab.]|[Dept. of Medical Elementology and Toxicology, New Delhi (India); Athar, M. [Dept. of Medical Elementology and Toxicology, New Delhi (India)

1999-07-01

Apoptosis or programmed cell death is a highly conserved genetically controlled response of metazoan cells to commit suicide. Non apoptotic programmed cell death seems to operate in single celled eukaryotes implying that evolution of PCD has preceded the evolution of multicellularity. PCD plays a crucial role in the regulation of cellular and tissue homeostasis and any aberrations in apoptosis leads to several diseases including cancer, neurodegenerative disorders and AIDS. The mechanisms by which apoptosis is controlled are varied. In some cells, members of bcl-2 family or p53 are crucial for regulating the apoptosis programme, whereas in other cells Fas ligand is more important. bcl-2 family members have a prime role in the regulation of cell death at all stages including development, whereas cell death during development is independent of p53. bcl-2 family members being localized on the outer mitochondrial membrane, control the mitochondrial homeostasis and cytochrome c redistribution and thereby regulate the cell death process. p53 promotes DNA damage mediated cell death after growth arrest and failed DNA repair. Caspases play a key role in the execution of cell death by mediating highly specific cleavages of crucial cellular proteins collectivley manifesting the apoptotic phenotype. Protein inhibitors like crm A, p35 and IAPs could prevent/control apoptosis induced by a broad array of cell death stimuli by several mechanisms specially interfering in caspase activation or caspase activity. Among endonucleases, caspase activated DNase (CAD) plays a crucial role in DNA fragmentation, a biochemical hallmark of apoptosis. As regulation of cell death seems to be as complex as regulation of cell proliferation, multiple kinase mediated regulatory mechanisms might control the apoptotic process. Thus, in spite of intensive research over the past few years, the field of apoptosis still remains fertile to unravel among others, the molecular mechanisms of cytochrome c

Reemergence of apoptotic cells between fractionated doses in irradiated murine tumors

International Nuclear Information System (INIS)

Meyn, R.E.; Hunter, N.R.; Milas, L.

1994-01-01

The purpose of this investigation was to follow up our previous studies on the development of apoptosis in irradiated murine tumors by testing whether an apoptotic subpopulation of cells reemerges between fractionated exposures. Mice bearing a murine ovarian carcinoma, OCa-I, were treated in vivo with two fractionation protocols: two doses of 12.5 Gy separated by various times out to 5 days and multiple daily fractions of 2.5 Gy. Animals were killed 4 h after the last dose in each protocol, and the percent apoptosis was scored from stained histological sections made from the irradiated tumors according to the specific features characteristic of this mode of cell death. The 12.5+12.5 Gy protocol yielded a net total percent apoptosis of about 45% when the two doses were separated by 5 days (total dose = 25 Gy), whereas the 2.5 Gy per day protocol yielded about 50% net apoptotic cells when given for 5 days (total dose = 12.5 Gy). These values are to be compared to the value of 36% apoptotic cells that is yielded by large single doses (> 25 Gy). Thus, these results indicate that an apoptotic subpopulation of cells reemerged between the fractions in both protocols, but the kinetics appeared to be delayed in the 12.5+12.5 Gy vs. the multiple 2.5 Gy protocol. This reemergence of cells with the propensity for radiation-induced apoptosis between fractionated exposures is consistent with a role for this mode of cell death in the response of tumors to radiotherapy and may represent the priming of a new subpopulation of tumor cells for apoptosis as part of normal tumor homeostasis to counterbalance cell division. 25 refs., 3 figs., 1 tab

Repeated Exposure of Epithelial Cells to Apoptotic Cells Induces the Specific Selection of an Adaptive Phenotype: Implications for Tumorigenesis.

Science.gov (United States)

Feng, Lanfei; Vujicic, Snezana; Dietrich, Michael E; Litbarg, Natalia; Setty, Suman; Antoni, Angelika; Rauch, Joyce; Levine, Jerrold S

2018-05-16

The consequences of apoptosis extend beyond mere death of the cell. We have shown that receptor-mediated recognition of apoptotic target cells by viable kidney proximal tubular epithelial cells (PTECs) inhibits PTEC proliferation, growth, and survival. Here we tested the hypothesis that continual exposure to apoptotic targets can induce a phenotypic change in responding PTECs, as in other instances of natural selection. In particular, we demonstrate that repeated exposure to apoptotic targets leads to emergence of a PTEC line (denoted BU.MPT SEL ) resistant to apoptotic target-induced death. Resistance is exquisitely specific. Not only are BU.MPT SEL responders fully resistant to apoptotic target-induced death (~85% survival versus exposure in selected versus non-selected responders indicated that the acquired resistance of BU.MPT SEL cells lies in a regulatory step affecting the generation of the pro-apoptotic protein, truncated BH3 interacting-domain death agonist (tBID), most likely at the level of BID cleavage by caspase-8. This specific adaptation has especial relevance for cancer, in which the prominence and persistence of cell death entail magnification of the post-mortem effects of apoptotic cells. Just as cancer cells acquire specific resistance to chemotherapeutic agents, we propose that cancer cells may also adapt to their ongoing exposure to apoptotic targets. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

In vitro assays for predicting tumor cell response to radiation by apoptotic pathways

International Nuclear Information System (INIS)

Algan, Oe.; Hanks, G.E.; Biade, S.; Chapman, J.D.

1995-01-01

Purpose: We had previously shown that the rate of spontaneous and radiation-induced apoptosis was significantly greater in well-differentiated compared to anaplastic Dunning prostate carcinomas. The goal of this study was to define the most useful assay for quantifying radiation-induced apoptotic cell death and to determine if measured rates of radiation-induced apoptosis in tumor cell populations can predict treatment outcome. Materials and Methods: The time course and extent of radiation-induced apoptosis after single doses of Cesium-137 gamma-rays were measured by five different assays. These included gross DNA degradation, nucleosome ladder formation, labeling of 3'-OH ends in DNA with an immunofluorescence probe, immunofluorescence vital stains (LIVE/DEAD[reg] EUKOLIGHT TM ) and trypan blue. The majority of these studies were performed with DU-145 human prostate cells. Data was analyzed to determine the component of cell inactivation resulting from apoptosis with the modified linear quadratic equation, -1n (SF) = (α a + α p ) D + β p D 2 , were α a represents cell inactivation by radiation-induced apoptosis, α p and β p represent cell death by proliferative mechanisms and D represents radiation dose. Results: These studies indicated that DU-145 cell death after radiation occurs over two distinct time periods. The first phase of death begins shortly after irradiation and plateaus within 16-24 hr. This process of cell death has properties consistent with apoptosis as determined by 3'-OH DNA end-labeling and nucleosome ladder assays. The second phase of cell death (determined by viability staining) begins approximately 48 hr after irradiation and continues until the remainder of inactivated cells express their death. This longer phase of cell inactivation probably represents proliferative cell death and other non-apoptotic mechanisms. The five different assays were performed on DU-145 cells 24 hr after irradiation with 10 Gy. Significant nucleosome ladders

Mitochondrial apoptotic pathways induced by Drosophila programmed cell death regulators

International Nuclear Information System (INIS)

Claveria, Cristina; Torres, Miguel

2003-01-01

Multicellular organisms eliminate unwanted or damaged cells by cell death, a process essential to the maintenance of tissue homeostasis. Cell death is a tightly regulated event, whose alteration by excess or defect is involved in the pathogenesis of many diseases such as cancer, autoimmune syndromes, and neurodegenerative processes. Studies in model organisms, especially in the nematode Caenorhabditis elegans, have been crucial in identifying the key molecules implicated in the regulation and execution of programmed cell death. In contrast, the study of cell death in Drosophila melanogaster, often an excellent model organism, has identified regulators and mechanisms not obviously conserved in other metazoans. Recent molecular and cellular analyses suggest, however, that the mechanisms of action of the main programmed cell death regulators in Drosophila include a canonical mitochondrial pathway

Induction of discrete apoptotic pathways by bromo-substituted indirubin derivatives in invasive breast cancer cells

Energy Technology Data Exchange (ETDEWEB)

Nicolaou, Katerina A. [Department of Biological Sciences, University of Cyprus, Nicosia (Cyprus); Liapis, Vasilis; Evdokiou, Andreas [Department of Surgery, Basil Hetzel Institute, Adelaide University, Adelaide (Australia); Constantinou, Constantina [St. George' s University of London Medical School at the University of Nicosia, Nicosia (Cyprus); Magiatis, Prokopios; Skaltsounis, Alex L. [Faculty of Pharmacy, University of Athens, Athens (Greece); Koumas, Laura; Costeas, Paul A. [Center for Study of Hematological Malignancies, Nicosia (Cyprus); Constantinou, Andreas I., E-mail: andreasc@ucy.ac.cy [Department of Biological Sciences, University of Cyprus, Nicosia (Cyprus)

2012-08-17

Highlights: Black-Right-Pointing-Pointer The effects of 6BIO and 7BIO are evaluated against five breast cancer cell lines. Black-Right-Pointing-Pointer 6BIO induces a caspase dependent apoptotic effect via the intrinsic pathway. Black-Right-Pointing-Pointer 7BIO promotes G{sub 2}/M cells cycle arrest. Black-Right-Pointing-Pointer 7BIO triggers a caspase-8 mediated apoptotic pathway. Black-Right-Pointing-Pointer 7BIO triggers and a caspase independent pathway. -- Abstract: Indirubin derivatives gained interest in recent years for their anticancer and antimetastatic properties. The objective of the present study was to evaluate and compare the anticancer properties of the two novel bromo-substituted derivatives 6-bromoindirubin-3 Prime -oxime (6BIO) and 7-bromoindirubin-3 Prime -oxime (7BIO) in five different breast cancer cell lines. Cell viability assays identified that 6BIO and 7BIO are most effective in preventing the proliferation of the MDA-MB-231-TXSA breast cancer cell line from a total of five breast cancer cell lined examined. In addition it was found that the two compounds induce apoptosis via different mechanisms. 6BIO induces caspase-dependent programmed cell death through the intrinsic (mitochondrial) caspase-9 pathway. 7BIO up-regulates p21 and promotes G{sub 2}/M cell cycle arrest which is subsequently followed by the activation of two different apoptotic pathways: (a) a pathway that involves the upregulation of DR4/DR5 and activation of caspase-8 and (b) a caspase independent pathway. In conclusion, this study provides important insights regarding the molecular pathways leading to cell cycle arrest and apoptosis by two indirubin derivatives that can find clinical applications in targeted cancer therapeutics.

Apoptotic Cell Death Induced by Resveratrol Is Partially Mediated by the Autophagy Pathway in Human Ovarian Cancer Cells.

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Fangfang Lang

Full Text Available Resveratrol (trans-3,4,5'-trihydroxystilbene is an active compound in food, such as red grapes, peanuts, and berries. Resveratrol exhibits an anticancer effect on various human cancer cells. However, the mechanism of resveratrol-induced anti-cancer effect at the molecular level remains to be elucidated. In this study, the mechanism underlying the anti-cancer effect of resveratrol in human ovarian cancer cells (OVCAR-3 and Caov-3 was investigated using various molecular biology techniques, such as flow cytometry, western blotting, and RNA interference, with a major focus on the potential role of autophagy in resveratrol-induced apoptotic cell death. We demonstrated that resveratrol induced reactive oxygen species (ROS generation, which triggers autophagy and subsequent apoptotic cell death. Resveratrol induced ATG5 expression and promoted LC3 cleavage. The apoptotic cell death induced by resveratrol was attenuated by both pharmacological and genetic inhibition of autophagy. The autophagy inhibitor chloroquine, which functions at the late stage of autophagy, significantly reduced resveratrol-induced cell death and caspase 3 activity in human ovarian cancer cells. We also demonstrated that targeting ATG5 by siRNA also suppressed resveratrol-induced apoptotic cell death. Thus, we concluded that a common pathway between autophagy and apoptosis exists in resveratrol-induced cell death in OVCAR-3 human ovarian cancer cells.

Apoptotic intrinsic pathway proteins predict survival in canine cutaneous mast cell tumours.

Science.gov (United States)

Barra, C N; Macedo, B M; Cadrobbi, K G; Pulz, L H; Huete, G C; Kleeb, S R; Xavier, J G; Catão-Dias, J L; Nishiya, A T; Fukumasu, H; Strefezzi, R F

2018-03-01

Mast cell tumours (MCTs) are the most frequent canine round cell neoplasms and show variable biological behaviours with high metastatic and recurrence rates. The disease is treated surgically and wide margins are recommended. Adjuvant chemotherapy and radiotherapy used in this disease cause DNA damage in neoplastic cells, which is aimed to induce apoptotic cell death. Resisting cell death is a hallmark of cancer, which contributes to the development and progression of tumours. The aim of this study was to investigate the expression of the proteins involved in the apoptotic intrinsic pathway and to evaluate their potential use as prognostic markers for canine cutaneous MCTs. Immunohistochemistry for BAX, BCL2, APAF1, Caspase-9, and Caspase-3 was performed in 50 canine cases of MCTs. High BAX expression was associated with higher mortality rate and shorter survival. BCL2 and APAF1 expressions offered additional prognostic information to the histopathological grading systems. The present results indicate that variations in the expression of apoptotic proteins are related to malignancy of cutaneous MCTs in dogs. © 2017 John Wiley & Sons Ltd.

Protein C Inhibitor (PCI) Binds to Phosphatidylserine Exposing Cells with Implications in the Phagocytosis of Apoptotic Cells and Activated Platelets

Science.gov (United States)

Rieger, Daniela; Assinger, Alice; Einfinger, Katrin; Sokolikova, Barbora; Geiger, Margarethe

2014-01-01

Protein C Inhibitor (PCI) is a secreted serine protease inhibitor, belonging to the family of serpins. In addition to activated protein C PCI inactivates several other proteases of the coagulation and fibrinolytic systems, suggesting a regulatory role in hemostasis. Glycosaminoglycans and certain negatively charged phospholipids, like phosphatidylserine, bind to PCI and modulate its activity. Phosphatidylerine (PS) is exposed on the surface of apoptotic cells and known as a phagocytosis marker. We hypothesized that PCI might bind to PS exposed on apoptotic cells and thereby influence their removal by phagocytosis. Using Jurkat T-lymphocytes and U937 myeloid cells, we show here that PCI binds to apoptotic cells to a similar extent at the same sites as Annexin V, but in a different manner as compared to live cells (defined spots on ∼10–30% of cells). PCI dose dependently decreased phagocytosis of apoptotic Jurkat cells by U937 macrophages. Moreover, the phagocytosis of PS exposing, activated platelets by human blood derived monocytes declined in the presence of PCI. In U937 cells the expression of PCI as well as the surface binding of PCI increased with time of phorbol ester treatment/macrophage differentiation. The results of this study suggest a role of PCI not only for the function and/or maturation of macrophages, but also as a negative regulator of apoptotic cell and activated platelets removal. PMID:25000564

The regulation of apoptotic cell death

Directory of Open Access Journals (Sweden)

Amarante-Mendes G.P.

1999-01-01

Full Text Available Apoptosis is a fundamental biological phenomenon in which the death of a cell is genetically and biochemically regulated. Different molecules are involved in the regulation of the apoptotic process. Death receptors, coupled to distinct members of the caspases as well as other adapter molecules, are involved in the initiation of the stress signals (The Indictment. Members of the Bcl-2 family control at the mitochondrial level the decision between life and death (The Judgement. The effector caspases are responsible for all morphological and biochemical changes related to apoptosis including the "eat-me" signals perceived by phagocytes and neighboring cells (The Execution. Finally, apoptosis would have little biological significance without the recognition and removal of the dying cells (The Burial.

Apoptotic effects of bovine apo-lactoferrin on HeLa tumor cells.

Science.gov (United States)

Luzi, Carla; Brisdelli, Fabrizia; Iorio, Roberto; Bozzi, Argante; Carnicelli, Veronica; Di Giulio, Antonio; Lizzi, Anna Rita

2017-01-01

Lactoferrin (Lf), a cationic iron-binding glycoprotein of 80 kDa present in body secretions, is known as a compound with marked antimicrobial activity. In the present study, the apoptotic effect of iron-free bovine lactoferrin (apo-bLf) on human epithelial cancer (HeLa) cells was examined in association with reactive oxygen species and glutathione (GSH) levels. Apoptotic effect of iron-free bovine lactoferrin inhibited the growth of HeLa cells after 48 hours of treatment while the diferric-bLf was ineffective in the concentration range tested (from 1 to 12.5 μM). Western blot analysis showed that key apoptotic regulators including Bax, Bcl-2, Sirt1, Mcl-1, and PARP-1 were modulated by 1.25 μM of apo-bLf. In the same cell line, apo-bLf induced apoptosis together with poly (ADP-ribose) polymerase cleavage, caspase activation, and a significant drop of NAD + . In addition, apo-bLf-treated HeLa cells showed a marked increase of reactive oxygen species level and a significant GSH depletion. On the whole, apo-bLf triggered apoptosis of HeLa cells upon oxygen radicals burst and GSH decrease. Copyright © 2017 John Wiley & Sons, Ltd.

Mitochondrial fission proteins regulate programmed cell death in yeast

OpenAIRE

Fannjiang, Yihru; Cheng, Wen-Chih; Lee, Sarah J.; Qi, Bing; Pevsner, Jonathan; McCaffery, J. Michael; Hill, R. Blake; Basañez, Gorka; Hardwick, J. Marie

2004-01-01

The possibility that single-cell organisms undergo programmed cell death has been questioned in part because they lack several key components of the mammalian cell death machinery. However, yeast encode a homolog of human Drp1, a mitochondrial fission protein that was shown previously to promote mammalian cell death and the excessive mitochondrial fragmentation characteristic of apoptotic mammalian cells. In support of a primordial origin of programmed cell death involving mitochondria, we fo...

Macrophages discriminate glycosylation patterns of apoptotic cell-derived microparticles.

Science.gov (United States)

Bilyy, Rostyslav O; Shkandina, Tanya; Tomin, Andriy; Muñoz, Luis E; Franz, Sandra; Antonyuk, Volodymyr; Kit, Yuriy Ya; Zirngibl, Matthias; Fürnrohr, Barbara G; Janko, Christina; Lauber, Kirsten; Schiller, Martin; Schett, Georg; Stoika, Rostyslav S; Herrmann, Martin

2012-01-02

Inappropriate clearance of apoptotic remnants is considered to be the primary cause of systemic autoimmune diseases, like systemic lupus erythematosus. Here we demonstrate that apoptotic cells release distinct types of subcellular membranous particles (scMP) derived from the endoplasmic reticulum (ER) or the plasma membrane. Both types of scMP exhibit desialylated glycotopes resulting from surface exposure of immature ER-derived glycoproteins or from surface-borne sialidase activity, respectively. Sialidase activity is activated by caspase-dependent mechanisms during apoptosis. Cleavage of sialidase Neu1 by caspase 3 was shown to be directly involved in apoptosis-related increase of surface sialidase activity. ER-derived blebs possess immature mannosidic glycoepitopes and are prioritized by macrophages during clearance. Plasma membrane-derived blebs contain nuclear chromatin (DNA and histones) but not components of the nuclear envelope. Existence of two immunologically distinct types of apoptotic blebs may provide new insights into clearance-related diseases.

Anti-apoptotic effect of hyperglycemia can allow survival of potentially autoreactive T cells.

Science.gov (United States)

Ramakrishnan, P; Kahn, D A; Baltimore, D

2011-04-01

Thymocyte development is a tightly controlled multi-step process involving selective elimination of self-reactive and non-functional T cells by apoptosis. This developmental process depends on signaling by Notch, IL-7 and active glucose metabolism. In this study, we explored the requirement of glucose for thymocyte survival and found that in addition to metabolic regulation, glucose leads to the expression of anti-apoptotic genes. Under hyperglycemic conditions, both mouse and human thymocytes demonstrate enhanced survival. We show that glucose-induced anti-apoptotic genes are dependent on NF-κB p65 because high glucose is unable to attenuate normal ongoing apoptosis of thymocytes isolated from p65 knockout mice. Furthermore, we demonstrate that in vivo hyperglycemia decreases apoptosis of thymocytes allowing for survival of potentially self-reactive thymocytes. These results imply that hyperglycemic conditions could contribute to the development of autoimmunity through dysregulated thymic selection. © 2011 Macmillan Publishers Limited

T Cell Zone Resident Macrophages Silently Dispose of Apoptotic Cells in the Lymph Node.

Science.gov (United States)

Baratin, Myriam; Simon, Léa; Jorquera, Audrey; Ghigo, Clément; Dembele, Doulaye; Nowak, Jonathan; Gentek, Rebecca; Wienert, Stephan; Klauschen, Frederick; Malissen, Bernard; Dalod, Marc; Bajénoff, Marc

2017-08-15

In lymph nodes (LNs), dendritic cells (DCs) are thought to dispose of apoptotic cells, a function pertaining to macrophages in other tissues. We found that a population of CX3CR1 + MERTK + cells located in the T cell zone of LNs, previously identified as DCs, are efferocytic macrophages. Lineage-tracing experiments and shield chimeras indicated that these T zone macrophages (TZM) are long-lived macrophages seeded in utero and slowly replaced by blood monocytes after birth. Imaging the LNs of mice in which TZM and DCs express different fluorescent proteins revealed that TZM-and not DCs-act as the only professional scavengers, clearing apoptotic cells in the LN T cell zone in a CX3CR1-dependent manner. Furthermore, similar to other macrophages, TZM appear inefficient in priming CD4 T cells. Thus, efferocytosis and T cell activation in the LN are uncoupled processes designated to macrophages and DCs, respectively, with implications to the maintenance of immune homeostasis. Copyright © 2017 Elsevier Inc. All rights reserved.

Targeting multiple pro-apoptotic signaling pathways with curcumin in prostate cancer cells.

Directory of Open Access Journals (Sweden)

Mariela Rivera

Full Text Available Curcumin, an extract from the turmeric rhizome (Curcuma longa, is known to exhibit anti-inflammatory, antioxidant, chemopreventive and antitumoral activities against aggressive and recurrent cancers. Accumulative data indicate that curcumin may induce cancer cell death. However, the detailed mechanism underlying its pro-apoptotic and anti-cancer effects remains to be elucidated. In the present study, we examined the signaling pathways triggered by curcumin, specifically, the exact molecular mechanisms of curcumin-induced apoptosis in highly metastatic human prostate cancer cells. The effect of curcumin was evaluated using for the first time in prostate cancer, a gel-free shotgun quantitative proteomic analysis coupled with Tandem Mass Tag isobaric labeling-based-signaling networks. Results were confirmed at the gene expression level by qRT-PCR and at the protein expression level by western blot and flow cytometry. Our findings revealed that curcumin induced an Endoplasmic Reticulum stress-mediated apoptosis in PC3. The mechanisms by which curcumin promoted cell death in these cells were associated with cell cycle arrest, increased reactive oxygen species, autophagy and the Unfolded Protein Response. Furthermore, the upregulation of ER stress was measured using key indicators of ER stress: Glucose-Regulated Protein 78, Inositol-Requiring Enzyme 1 alpha, Protein Disulfide isomerase and Calreticulin. Chronic ER stress induction was concomitant with the upregulation of pro-apoptotic markers (caspases 3,9,12 and Poly (ADP-ribose polymerase. The downregulated proteins include anti-apoptotic and anti-tumor markers, supporting their curcumin-induced pro-apoptotic role in prostate cancer cells. Taken together, these data suggest that curcumin may serve as a promising anticancer agent by inducing a chronic ER stress mediated cell death and activation of cell cycle arrest, UPR, autophagy and oxidative stress responses.

Targeting multiple pro-apoptotic signaling pathways with curcumin in prostate cancer cells

Science.gov (United States)

Rivera, Mariela; Ramos, Yanilda; Rodríguez-Valentín, Madeline; López-Acevedo, Sheila; Cubano, Luis A.; Zou, Jin; Zhang, Qiang; Wang, Guangdi

2017-01-01

Curcumin, an extract from the turmeric rhizome (Curcuma longa), is known to exhibit anti-inflammatory, antioxidant, chemopreventive and antitumoral activities against aggressive and recurrent cancers. Accumulative data indicate that curcumin may induce cancer cell death. However, the detailed mechanism underlying its pro-apoptotic and anti-cancer effects remains to be elucidated. In the present study, we examined the signaling pathways triggered by curcumin, specifically, the exact molecular mechanisms of curcumin-induced apoptosis in highly metastatic human prostate cancer cells. The effect of curcumin was evaluated using for the first time in prostate cancer, a gel-free shotgun quantitative proteomic analysis coupled with Tandem Mass Tag isobaric labeling-based-signaling networks. Results were confirmed at the gene expression level by qRT-PCR and at the protein expression level by western blot and flow cytometry. Our findings revealed that curcumin induced an Endoplasmic Reticulum stress-mediated apoptosis in PC3. The mechanisms by which curcumin promoted cell death in these cells were associated with cell cycle arrest, increased reactive oxygen species, autophagy and the Unfolded Protein Response. Furthermore, the upregulation of ER stress was measured using key indicators of ER stress: Glucose-Regulated Protein 78, Inositol-Requiring Enzyme 1 alpha, Protein Disulfide isomerase and Calreticulin. Chronic ER stress induction was concomitant with the upregulation of pro-apoptotic markers (caspases 3,9,12) and Poly (ADP-ribose) polymerase. The downregulated proteins include anti-apoptotic and anti-tumor markers, supporting their curcumin-induced pro-apoptotic role in prostate cancer cells. Taken together, these data suggest that curcumin may serve as a promising anticancer agent by inducing a chronic ER stress mediated cell death and activation of cell cycle arrest, UPR, autophagy and oxidative stress responses. PMID:28628644

Sesamol induced apoptotic effect in lung adenocarcinoma cells through both intrinsic and extrinsic pathways.

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Siriwarin, Boondaree; Weerapreeyakul, Natthida

2016-07-25

Sesamol is a phenolic lignan found in sesame seeds (Sesamum indicum L.) and sesame oil. The anticancer effects and molecular mechanisms underlying its apoptosis-inducing effect were investigated in human lung adenocarcinoma (SK-LU-1) cells. Sesamol inhibited SK-LU-1 cell growth with an IC50 value of 2.7 mM and exhibited less toxicity toward normal Vero cells after 48 h of treatment (Selective index = 3). Apoptotic bodies-the hallmark of apoptosis-were observed in sesamol-treated SK-LU-1 cells, stained with DAPI. Sesamol increased the activity of caspase 8, 9, and 3/7, indicating that apoptotic cell death occurred through both extrinsic and intrinsic pathways. Sesamol caused the loss of mitochondrial transmembrane potential signifying intrinsic apoptosis induction. Decreasing Bid expression revealed crosstalk between the intrinsic and extrinsic apoptotic pathways; demonstrating clearly that sesamol induces apoptosis through both pathways in human lung adenocarcinoma (SK-LU-1) cells. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Untangling the Roles of Anti-Apoptosis in Regulating Programmed Cell Death using Humanized Yeast Cells

International Nuclear Information System (INIS)

Clapp, Caitlin; Portt, Liam; Khoury, Chamel; Sheibani, Sara; Eid, Rawan; Greenwood, Matthew; Vali, Hojatollah; Mandato, Craig A.; Greenwood, Michael T.

2012-01-01

Genetically programmed cell death (PCD) mechanisms, including apoptosis, are important for the survival of metazoans since it allows, among things, the removal of damaged cells that interfere with normal function. Cell death due to PCD is observed in normal processes such as aging and in a number of pathophysiologies including hypoxia (common causes of heart attacks and strokes) and subsequent tissue reperfusion. Conversely, the loss of normal apoptotic responses is associated with the development of tumors. So far, limited success in preventing unwanted PCD has been reported with current therapeutic approaches despite the fact that inhibitors of key apoptotic inducers such as caspases have been developed. Alternative approaches have focused on mimicking anti-apoptotic processes observed in cells displaying increased resistance to apoptotic stimuli. Hormesis and pre-conditioning are commonly observed cellular strategies where sub-lethal levels of pro-apoptotic stimuli lead to increased resistance to higher or lethal levels of stress. Increased expression of anti-apoptotic sequences is a common mechanism mediating these protective effects. The relevance of the latter observation is exemplified by the observation that transgenic mice overexpressing anti-apoptotic genes show significant reductions in tissue damage following ischemia. Thus strategies aimed at increasing the levels of anti-apoptotic proteins, using gene therapy or cell penetrating recombinant proteins are being evaluated as novel therapeutics to decrease cell death following acute periods of cell death inducing stress. In spite of its functional and therapeutic importance, more is known regarding the processes involved in apoptosis than anti-apoptosis. The genetically tractable yeast Saccharomyces cerevisiae has emerged as an exceptional model to study multiple aspects of PCD including the mitochondrial mediated apoptosis observed in metazoans. To increase our knowledge of the process of anti

Induction of apoptotic cell death by putrescine

DEFF Research Database (Denmark)

Takao, Koichi; Rickhag, Karl Mattias; Hegardt, Cecilia

2006-01-01

that overexpression of a metabolically stable ODC in CHO cells induced a massive cell death unless the cells were grown in the presence of the ODC inhibitor alpha-difluoromethylornithine (DFMO). Cells overexpressing wild-type (unstable) ODC, on the other hand, were not dependent on the presence of DFMO...... for their growth. The induction of cell death was correlated with a dramatic increase in cellular putrescine levels. Analysis using flow cytometry revealed perturbed cell cycle kinetics, with a large accumulation of cells with sub-G1 amounts of DNA, which is a typical sign of apoptosis. Another strong indication...... of apoptosis was the finding that one of the key enzymes in the apoptotic process, caspase-3, was induced when DFMO was omitted from the growth medium. Furthermore, inhibition of the caspase activity significantly reduced the recruitment of cells to the sub-G1 fraction. In conclusion, deregulation of polyamine...

Free cholesterol accumulation impairs antioxidant activities and aggravates apoptotic cell death in menadione-induced oxidative injury.

Science.gov (United States)

Lee, Waisin; Xu, Mingjing; Li, Yue; Gu, Yong; Chen, Jianping; Wong, Derek; Fung, Peter C W; Shen, Jiangang

2011-10-01

Although the relationship between hypercholesterolemia and oxidative stress has been extensively investigated, direct evidence regarding to the roles of cholesterol accumulation in the generations of reactive oxygen species (ROS) and apoptotic cell death under oxidative stress is lack. In this study, we investigated productions of superoxide anions (O(2)(-)) and nitric oxide (NO), and apoptotic cell death in wild type Chinese hamster ovary (CHO) cells and cholesterol accumulated CHO cells genetically and chemically. Oxidative stress was induced by menadione challenge. The results revealed that abundance of free cholesterol (FC) promoted menadione-induced O(2)(-) and NO productions. FC accumulation down-regulated eNOS expression but up-regulated NADPH oxidases, and inhibited the activities of superoxide dismutase (SOD) and catalase. Treatment of menadione increased the expressions of iNOS and qp91 phox, enhanced the activities of SOD and catalase in the wild-type CHO cells but inhibited the activity of glutathione peroxidase in the cholesterol accumulated CHO cells. Moreover, FC abundance promoted apoptotic cell death in these cells. Taken together, those results suggest that free cholesterol accumulation aggravates menadione-induced oxidative stress and exacerbates apoptotic cell death. Copyright © 2011 Elsevier Inc. All rights reserved.

Differential regulation of caspase-9 by ionizing radiation- and UV-induced apoptotic pathways in thymic cells

Energy Technology Data Exchange (ETDEWEB)

Okamoto, Mayumi; Koga, Satomi [Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Hiroshima 727-0023 (Japan); Tatsuka, Masaaki, E-mail: tatsuka@pu-hiroshima.ac.jp [Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Hiroshima 727-0023 (Japan)

2010-06-01

In mouse thymic lymphoma 3SB cells bearing wild type p53, ionizing radiation (IR) and UV light are potent triggers of caspase-3-dependent apoptosis. Although cytochrome c was released from mitochondria as expected, caspase-9 activation was not observed in UV-exposed cells. Laser scanning confocal microscopy analysis showed that caspase-9 is localized in an unusual punctuated pattern in UV-induced apoptotic cells. In agreement with differences in the status of caspase-9 activation between IR and UV, subcellular protein fractionation experiments showed that pro-apoptotic apoptosis protease-activating factor 1 (Apaf-1), normally a part of the apoptosome assembled in response to the release of cytochrome c from mitochondria, and B-cell lymphoma extra long (Bcl-xL), an inhibitor of the change in mitochondrial membrane permeability, were redistributed by the IR-exposure but not by the UV-exposure. Instead of the sequestration of the capase-9/apoptosome activation in UV-induced apoptotic cells, the extrinsic apoptotic signaling generated by caspase-8 activation and consequent activation of B-cell lymphoma extra long (Bid) to release cytochrome c from mitochondria was observed. Thus, the post-mitochondrial apoptotic pathway downstream of cytochrome c release cannot operate the apoptosome function in UV-induced apoptosis in thymic 3SB cells. The intracellular redistribution and sequestration of apoptosis-related proteins upon mitochondrion-based apoptotic signaling was identified as a novel cellular mechanism to respond to DNA damage in an agent type-specific manner. This finding suggests that the kind of the critical ultimate apoptosis-inducing DNA lesion complex form resulting from the agent-specific DNA damage responses is important to determine which of apoptosis signals would be activated.

A histochemical comparison of methyl green-pyronin, and hematoxylin and eosin for detecting apoptotic cells in oral squamous cell carcinoma, oral leukoplakia, oral submucous fibrosis and normal oral mucosa.

Science.gov (United States)

Sumedha, S; Kotrashetti, V S; Somannavar, P; Nayak, R; Babji, D

2015-05-01

Analysis of apoptotic cells in oral pathological states could be useful for determining the rates of tissue turnover, which would help determine prognosis. The use of histochemical stains such as hematoxylin and eosin (H & E) and methyl green-pyronin (MGP) can provide a simple and cost-effective method for detecting apoptotic cells. We compared the efficacy of MGP and H & E for detecting apoptotic cells in oral squamous cell carcinoma (OSCC), oral leukoplakia (OL), oral submucous fibrosis (OSMF) and normal oral mucosa (NOM). Ten cases each of OSCC, OSMF, OL and NOM were retrieved from the archives and two serial sections were stained, one with H & E and the other with MGP. Apoptotic cells were identified at 100 x magnification and the apoptotic index was calculated. Apoptotic cells were distinguished more readily in MGP stained sections than in those stained with H & E. Also, the apoptotic cell count was greater in OSCC compared to OL, OSMF and NOM. We concluded that MGP staining can be used as a routine, cost-effective method for detecting apoptotic cells.

Transglutaminase 2 is needed for the formation of an efficient phagocyte portal in macrophages engulfing apoptotic cells.

Science.gov (United States)

Tóth, Beáta; Garabuczi, Eva; Sarang, Zsolt; Vereb, György; Vámosi, György; Aeschlimann, Daniel; Blaskó, Bernadett; Bécsi, Bálint; Erdõdi, Ferenc; Lacy-Hulbert, Adam; Zhang, Ailiang; Falasca, Laura; Birge, Raymond B; Balajthy, Zoltán; Melino, Gerry; Fésüs, László; Szondy, Zsuzsa

2009-02-15

Transglutaminase 2 (TG2), a protein cross-linking enzyme with many additional biological functions, acts as coreceptor for integrin beta(3). We have previously shown that TG2(-/-) mice develop an age-dependent autoimmunity due to defective in vivo clearance of apoptotic cells. Here we report that TG2 on the cell surface and in guanine nucleotide-bound form promotes phagocytosis. Besides being a binding partner for integrin beta(3), a receptor known to mediate the uptake of apoptotic cells via activating Rac1, we also show that TG2 binds MFG-E8 (milk fat globulin EGF factor 8), a protein known to bridge integrin beta(3) to apoptotic cells. Finally, we report that in wild-type macrophages one or two engulfing portals are formed during phagocytosis of apoptotic cells that are characterized by accumulation of integrin beta(3) and Rac1. In the absence of TG2, integrin beta(3) cannot properly recognize the apoptotic cells, is not accumulated in the phagocytic cup, and its signaling is impaired. As a result, the formation of the engulfing portals, as well as the portals formed, is much less efficient. We propose that TG2 has a novel function to stabilize efficient phagocytic portals.

Ion transport in a human lens epithelial cell line exposed to hyposmotic and apoptotic stress.

Science.gov (United States)

Chimote, Ameet A; Adragna, Norma C; Lauf, Peter K

2010-04-01

Membrane transport changes in human lens epithelial (HLE-B3) cells under hyposmotic and apoptotic stress were compared. Cell potassium content, K(i), uptake of the K congener rubidium, Rb(i), and water content were measured after hyposmotic stress induced by hypotonicity, and apoptotic stress by the protein-kinase inhibitor staurosporine (STP). Cell water increased in hyposmotic (150 mOsm) as compared to isosmotic (300 mOsm) balanced salt solution (BSS) by >2-fold at 5 min and decreased within 15 min to baseline values accompanied by a 40% K(i) loss commensurate with cell swelling and subsequent cell shrinkage likely due to regulatory volume decrease (RVD). Loss of K(i), and accompanying water, and Rb(i) uptake in hyposmotic BSS were prevented by clotrimazole (CTZ) suggesting water shifts associated with K and Rb flux via intermediate conductance K (IK) channels, also detected at the mRNA and protein level. In contrast, 2 h after 2 microM STP exposure, the cells lost approximately 40% water and approximately 60% K(i), respectively, consistent with apoptotic volume decrease (AVD). Indeed, water and K(i) loss was at least fivefold greater after hyposmotic than after apoptotic stress. High extracellular K and 2 mM 4-aminopyridine (4-AP) but not CTZ significantly reduced apoptosis. Annexin labeling phosphatidylserine (PS) at 15 min suggested loss of lipid asymmetry. Quantitative PCR revealed significant IK channel expression during prolonged hyposmotic stress. Results suggest in HLE-B3 cells, IK channels likely partook in and were down regulated after RVD, whereas pro-apoptotic STP-activation of 4-AP-sensitive voltage-gated K channels preceded or accompanied PS externalization before subsequent apoptosis. J. Cell. Physiol. 223: 110-122, 2010. (c) 2009 Wiley-Liss, Inc.

Non-canonical programmed cell death mechanisms triggered by natural compounds.

Science.gov (United States)

Diederich, Marc; Cerella, Claudia

2016-10-01

Natural compounds are the fundament of pharmacological treatments and more than 50% of all anticancer drugs are of natural origins or at least derived from scaffolds present in Nature. Over the last 25 years, molecular mechanisms triggered by natural anticancer compounds were investigated. Emerging research showed that molecules of natural origins are useful for both preventive and therapeutic purposes by targeting essential hallmarks and enabling characteristics described by Hanahan and Weinberg. Moreover, natural compounds were able to change the differentiation status of selected cell types. One of the earliest response of cells treated by pharmacologically active compounds is the change of its morphology leading to ultra-structural perturbations: changes in membrane composition, cytoskeleton integrity, alterations of the endoplasmic reticulum, mitochondria and of the nucleus lead to formation of morphological alterations that are a characteristic of both compound and cancer type preceding cell death. Apoptosis and autophagy were traditionally considered as the most prominent cell death or cell death-related mechanisms. By now multiple other cell death modalities were described and most likely involved in response to chemotherapeutic treatment. It can be hypothesized that especially necrosis-related phenotypes triggered by various treatments or evolving from apoptotic or autophagic mechanisms, provide a more efficient therapeutic outcome depending on cancer type and genetic phenotype of the patient. In fact, the recent discovery of multiple regulated forms of necrosis and the initial elucidation of the corresponding cell signaling pathways appear nowadays as important tools to clarify the immunogenic potential of non-canonical forms of cell death induction. Copyright © 2016 Elsevier Ltd. All rights reserved.

Time-resolved, single-cell analysis of induced and programmed cell death via non-invasive propidium iodide and counterstain perfusion.

Science.gov (United States)

Krämer, Christina E M; Wiechert, Wolfgang; Kohlheyer, Dietrich

2016-09-01

Conventional propidium iodide (PI) staining requires the execution of multiple steps prior to analysis, potentially affecting assay results as well as cell vitality. In this study, this multistep analysis method has been transformed into a single-step, non-toxic, real-time method via live-cell imaging during perfusion with 0.1 μM PI inside a microfluidic cultivation device. Dynamic PI staining was an effective live/dead analytical tool and demonstrated consistent results for single-cell death initiated by direct or indirect triggers. Application of this method for the first time revealed the apparent antibiotic tolerance of wild-type Corynebacterium glutamicum cells, as indicated by the conversion of violet fluorogenic calcein acetoxymethyl ester (CvAM). Additional implementation of this method provided insight into the induced cell lysis of Escherichia coli cells expressing a lytic toxin-antitoxin module, providing evidence for non-lytic cell death and cell resistance to toxin production. Finally, our dynamic PI staining method distinguished necrotic-like and apoptotic-like cell death phenotypes in Saccharomyces cerevisiae among predisposed descendants of nutrient-deprived ancestor cells using PO-PRO-1 or green fluorogenic calcein acetoxymethyl ester (CgAM) as counterstains. The combination of single-cell cultivation, fluorescent time-lapse imaging, and PI perfusion facilitates spatiotemporally resolved observations that deliver new insights into the dynamics of cellular behaviour.

Bioactive compounds from crocodile (Crocodylus siamensis) white blood cells induced apoptotic cell death in hela cells.

Science.gov (United States)

Patathananone, Supawadee; Thammasirirak, Sompong; Daduang, Jureerut; Chung, Jing Gung; Temsiripong, Yosapong; Daduang, Sakda

2016-08-01

Crocodile (Crocodylus siamensis) white blood cell extracts (WBCex) were examined for anticancer activity in HeLa cell lines using the MTT assay. The percentage viability of HeLa cells significantly deceased after treatment with WBCex in a dose- and time-dependent manner. The IC50 dose was suggested to be approximately 225 μg/mL protein. Apoptotic cell death occurred in a time-dependent manner based on investigation by flow cytometry using annexin V-FITC and PI staining. DAPI nucleic acid staining indicated increased chromatin condensation. Caspase-3, -8 and -9 activities also increased, suggesting the induction of the caspase-dependent apoptotic pathway. Furthermore, the mitochondrial membrane potential (ΔΨm ) of HeLa cells was lost as a result of increasing levels of Bax and reduced levels of Bcl-2, Bcl-XL, Bcl-Xs, and XIAP. The decreased ΔΨm led to the release of cytochrome c and the activation of caspase-9 and -3. Apoptosis-inducing factor translocated into the nuclei, and endonuclease G (Endo G) was released from the mitochondria. These results suggest that anticancer agents in WBCex can induce apoptosis in HeLa cells via both caspase-dependent and -independent pathways. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 986-997, 2016. © 2015 Wiley Periodicals, Inc.

Antitumor and apoptotic effects of cucurbitacin a in A-549 lung ...

African Journals Online (AJOL)

Background: The main aim of this study was to demonstrate the antitumor potential of cucurbitacin A on A-549 NSCLC (non-small cell lung cancer cells). The effects of Cucurbitacin A on apoptotic induction, cell physic, cell cycle failure and m-TOR/PI3K/Akt signalling pathway were also investigated in the present study.

Dynamic release of nuclear RanGTP triggers TPX2-dependent microtubule assembly during the apoptotic execution phase.

Science.gov (United States)

Moss, David K; Wilde, Andrew; Lane, Jon D

2009-03-01

During apoptosis, the interphase microtubule network is dismantled then later replaced by a novel, non-centrosomal microtubule array. These microtubules assist in the peripheral redistribution of nuclear fragments in the apoptotic cell; however, the regulation of apoptotic microtubule assembly is not understood. Here, we demonstrate that microtubule assembly depends upon the release of nuclear RanGTP into the apoptotic cytoplasm because this process is blocked in apoptotic cells overexpressing dominant-negative GDP-locked Ran (T24N). Actin-myosin-II contractility provides the impetus for Ran release and, consequently, microtubule assembly is blocked in blebbistatin- and Y27632-treated apoptotic cells. Importantly, the spindle-assembly factor TPX2 (targeting protein for Xklp2), colocalises with apoptotic microtubules, and siRNA silencing of TPX2, but not of the microtubule motors Mklp1 and Kid, abrogates apoptotic microtubule assembly. These data provide a molecular explanation for the assembly of the apoptotic microtubule network, and suggest important similarities with the process of RanGTP- and TPX2-mediated mitotic spindle formation.

Effects of Malnutrition on Neutrophil/Mononuclear Cell Apoptotic Functions in Children with Acute Lymphoblastic Leukemia.

Science.gov (United States)

Cakir, Fatma Betul; Berrak, Su Gülsün; Aydogan, Gonul; Tulunay, Aysin; Timur, Cetin; Canpolat, Cengiz; Eksioglu Demiralp, Emel

2017-04-01

Recent studies claim that apoptosis may explain immune dysfunction observed in malnutrition. The objective of this study was to determine the effect of malnutrition on apoptotic functions of phagocytic cells in acute lymphoblastic leukemia (ALL). Twenty-eight ALL patients (13 with malnutrition) and thirty controls were enrolled. Neutrophil and mononuclear cell apoptosis of ALL patients and the control group were studied on admission before chemotherapy and repeated at a minimum of three months after induction of chemotherapy or when the nutritional status of leukemic children improved. The apoptotic functions of both ALL groups on admission were significantly lower than those of the control group. The apoptotic functions were lower in ALL patients with malnutrition than those in ALL patients without malnutrition, but this was not statistically significant. The repeated apoptotic functions of both ALL groups were increased to similar values with the control group. This increase was found to be statistically significant. The apoptotic functions in ALL patients were not found to be affected by malnutrition. However, after dietary intervention, increased apoptotic functions in both ALL patient groups deserve mentioning. Dietary intervention should always be recommended as malnutrition or cachexia leads to multiple complications. Enhanced apoptosis might originate also from remission state of cancer.

Apoptotic pathways as regulators of recombination

International Nuclear Information System (INIS)

Gauny, S.S.; Kronenberg, A.; Liu, W.-C.

2003-01-01

Apoptosis, or programmed cell death (PCD), is a fundamental process that protects organismal integrity. In earlier work, we demonstrated that over-expression of either of two anti-apoptotic members of the BCL-2 family (BCL-2 or BCL-X L could elevate the frequency of radiation-induced mutations at the autosomal TK1 locus in human TK6 lymphoblasts that express wild-type TP53. Ectopic expression of BCL-X L also elevated the frequencies of double-strand break-induced gene conversion. The purpose of this study is to determine if BCL-2 family proteins promote radiation mutagenesis indirectly through their suppression of PCD, or whether the 'pro-mutagenic' function of these proteins can be separated from their anti-apoptotic function. We developed stable transfectants of TK6 cells that express a mutated form of BCL-X L with a single amino acid substitution in the BH1 domain that is known to interfere with the ability to suppress PCD (BCL-X L gly159ala). We also developed stable transfectants of TK6 cells that express a dominant negative caspase-9 that suppresses PCD. The results to date indicate that the mutated form of BCL-X L (gly159ala) does not suppress x-ray-induced PCD in TK6 cells, but it elevates radiation-induced TK1 mutant frequencies to the same extent as high level expression of wild-type BCL-X L . These data suggest that the anti-apoptotic function of BCL-2 family proteins is not required to elevate radiation mutagenesis. Separate experiments using TK6 cells that express a dominant negative caspase-9 indicate that this protein inhibits x-ray-induced PCD but TK1 mutant frequencies are not elevated. Taken together, the results suggest there is a separate function of BCL-2 family proteins that elevates radiation-induced mutagenesis independent of the well-known anti-apoptotic effect of these proteins of importance in human carcinogenesis

Increased endothelial apoptotic cell density in human diabetic erectile tissue--comparison with clinical data.

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Costa, Carla; Soares, Raquel; Castela, Angela; Adães, Sara; Hastert, Véronique; Vendeira, Pedro; Virag, Ronald

2009-03-01

Erectile dysfunction (ED) is a common complication of diabetes. Endothelial cell (EC) dysfunction is one of the main mechanisms of diabetic ED. However, loss of EC integrity has never been assessed in human diabetic corpus cavernosum. To identify and quantify apoptotic cells in human diabetic and normal erectile tissue and to compare these results with each patient's clinical data and erection status. Eighteen cavernosal samples were collected, 13 from diabetics with ED and 5 from nondiabetic individuals. Cavernosal structure and cell proliferation status were evaluated by immunohistochemistry. Tissue integrity was assessed by terminal transferase dUTP nick end labeling assay, an index of apoptotic cell density (ACD) established and compared with each patient age, type of diabetes, arterial risk factors number, arterial/veno-occlusive disease, response to intracavernous vasoactive injections (ICI), and penile nitric oxide release test (PNORT). Establish an index of ACD and correlate those results with patient clinical data. Nondiabetic samples presented few scattered cells in apoptosis and an ACD of 7.15 +/- 0.44 (mean apoptotic cells/tissue area mm(2) +/- standard error). The diabetic group showed an increased ACD of 23.82 +/- 1.53, and apoptotic cells were located specifically at vascular sites. Rehabilitation of these endothelial lesions seemed impaired, as no evidence of EC proliferation was observed. Furthermore, higher ACD in diabetic individuals correlated to poor response to PNORT and to ICI. We provided evidence for the first time that loss of cavernosal EC integrity is a crucial event involved in diabetic ED. Furthermore, we were able to establish a threshold between ACD values and cavernosal tissue functionality, as assessed by PNORT and vasoactive ICI.

Cypripedin, a phenanthrenequinone from Dendrobium densiflorum, sensitizes non-small cell lung cancer H460 cells to cisplatin-mediated apoptosis.

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Wattanathamsan, Onsurang; Treesuwan, Surassawadee; Sritularak, Boonchoo; Pongrakhananon, Varisa

2018-03-01

The life-threatening potential of lung cancer has increased over the years due to its acquisition of chemotherapeutic resistance, especially to cisplatin, a first-line therapy. In response to this development, researchers have turned their attention to several compounds derived from natural origins, including cypripedin (CYP), a phenanthrenequinone substance extracted from Dendrobium densiflorum. The aim of the present study was to investigate the ability of CYP to induce apoptosis and enhance cisplatin-mediated death of human lung cancer NCI-H460 cells using cell viability and apoptosis assays. The induction of apoptosis by CYP was observed at a concentration of > 50 μM with the appearance of morphological changes, including DNA condensation and chromatin fragmentation. Together with, CYP was able to activate caspase-3 and downregulate the anti-apoptotic proteins Bcl-2 and Bcl-xL. Also, a non-cytotoxic dose of CYP synergistically potentiated the effect of cisplatin in non-small cell lung cancer line H460 cells, which clearly exhibited the apoptotic phenotype. Western blot analysis revealed that the underlying mechanism involved the downregulation of anti-apoptotic Bcl-xL, whereas the levels of other apoptotic regulatory proteins were not altered. This study provides interesting information on the potent effect of CYP as a chemotherapeutic sensitizer that could be further developed to improve the clinical outcomes of lung cancer patients.

Poncirin Induces Apoptosis in AGS Human Gastric Cancer Cells through Extrinsic Apoptotic Pathway by up-Regulation of Fas Ligand.

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Saralamma, Venu Venkatarame Gowda; Nagappan, Arulkumar; Hong, Gyeong Eun; Lee, Ho Jeong; Yumnam, Silvia; Raha, Suchismita; Heo, Jeong Doo; Lee, Sang Joon; Lee, Won Sup; Kim, Eun Hee; Kim, Gon Sup

2015-09-18

Poncirin, a natural bitter flavanone glycoside abundantly present in many species of citrus fruits, has various biological benefits such as anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer activities. The anti-cancer mechanism of Poncirin remains elusive to date. In this study, we investigated the anti-cancer effects of Poncirin in AGS human gastric cancer cells (gastric adenocarcinoma). The results revealed that Poncirin could inhibit the proliferation of AGS cells in a dose-dependent manner. It was observed Poncirin induced accumulation of sub-G1 DNA content, apoptotic cell population, apoptotic bodies, chromatin condensation, and DNA fragmentation in a dose-dependent manner in AGS cells. The expression of Fas Ligand (FasL) protein was up-regulated dose dependently in Poncirin-treated AGS cells Moreover, Poncirin in AGS cells induced activation of Caspase-8 and -3, and subsequent cleavage of poly(ADP-ribose) polymerase (PARP). Inhibitor studies' results confirm that the induction of caspase-dependent apoptotic cell death in Poncirin-treated AGS cells was led by the Fas death receptor. Interestingly, Poncirin did not show any effect on mitochondrial membrane potential (ΔΨm), pro-apoptotic proteins (Bax and Bak) and anti-apoptotic protein (Bcl-xL) in AGS-treated cells followed by no activation in the mitochondrial apoptotic protein caspase-9. This result suggests that the mitochondrial-mediated pathway is not involved in Poncirin-induced cell death in gastric cancer. These findings suggest that Poncirin has a potential anti-cancer effect via extrinsic pathway-mediated apoptosis, possibly making it a strong therapeutic agent for human gastric cancer.

Atractylenolide-I Protects Human SH-SY5Y Cells from 1-Methyl-4-Phenylpyridinium-Induced Apoptotic Cell Death

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Sandeep Vasant More

2017-05-01

Full Text Available Oxidative stress and apoptosis are the major mechanisms that induce dopaminergic cell death. Our study investigates the protective effects of atractylenolide-I (ATR-I on 1-methyl-4-phenylpyridinium (MPP+-induced cytotoxicity in human dopaminergic SH-SY5Y cells, as well as its underlying mechanism. Our experimental data indicates that ATR-I significantly inhibits the loss of cell viability induced by MPP+ in SH-SY5Y cells. To further unravel the mechanism, we examined the effect of ATR-I on MPP+-induced apoptotic cell death characterized by an increase in the Bax/Bcl-2 mRNA ratio, the release of cytochrome-c, and the activation of caspase-3 leading to elevated levels of cleaved poly(ADP-ribose polymerase (PARP resulting in SH-SY5Y cell death. Our results demonstrated that ATR-I decreases the level of pro-apoptotic proteins induced by MPP+ and also restored Bax/Bcl-2 mRNA levels, which are critical for inducing apoptosis. In addition, ATR-I demonstrated a significant increase in the protein expression of heme-oxygenase in MPP+-treated SH-SY5Y cells. These results suggest that the pharmacological effect of ATR-I may be, at least in part, caused by the reduction in pro-apoptotic signals and also by induction of anti-oxidant protein.

Evaluation of apoptotic cell death in normal and chondrodystrophic canine intervertebral discs

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Marie Klauser

2012-02-01

Full Text Available Disc degeneration occurs commonly in dogs. A variety of factors is thought to contribute an inappropriate disc matrix that isolate cells in the disc and lead to apoptosis. Disc herniation with radiculopathy and discogenic pain are the results of the degenerative process. The objective of this prospective study was to determine the extent of apoptosis in intact and herniated intervertebral discs of chondrodystrophic dogs and non-chondrodystrophic dogs. In addition, the nucleus pulposus (NP was histologically compared between non-chondrodystrophic and chondrodystrophic dogs. Thoracolumbar intervertebral discs and parts of the extruded nucleus pulposus were harvested from 45 dogs. Samples were subsequently stained with haematoxylin-eosin and processed to detect cleaved caspase-3 and poly(ADP-ribose polymerase. A significant greater degree of apoptosis was observed in herniated NPs of chondrodystrophic dogs compared to non- chondrodystrophic dogs with poly (ADP-ribose polymerase and cleaved caspase- 3 detection. Within the group of chondrodystrophic dogs, dogs with an intact disc and younger than 6 years showed a significant lower incidence of apoptosis in the NP compared to the herniated NP of chondrodystrophic dogs. The extent of apoptosis in the annulus fibrosus was not different between the intact disc from chondrodystrophic and non- chondrodystrophic dogs. An age-related increase of apoptotic cells in NP and annulus fibrosus was found in the intact non-herniated intervertebral discs. Histologically, absence of notochordal cells and occurrence of chondroid metaplasia were observed in the nucleus pulposus of chondrodystrophic dogs. As a result, we found that apoptosis plays a role in disc degeneration in chondrodystrophic dogs.

Apoptosis in fish: environmental factors and programmed cell death.

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AnvariFar, Hossein; Amirkolaie, Abdolsamad Keramat; Miandare, Hamed Kolangi; Ouraji, Hossein; Jalali, M Ali; Üçüncü, Sema İşisağ

2017-06-01

Apoptosis, a form of programmed cell death, is a critical component in maintaining homeostasis and growth in all tissues and plays a significant role in immunity and cytotoxicity. In contrast to necrosis or traumatic cell death, apoptosis is a well-controlled and vital process characterized mainly by cytoplasmic shrinkage, chromatin condensation, DNA fragmentation, membrane blebbing and apoptotic bodies. Our understanding of apoptosis is partly based on observations in invertebrates but mainly in mammals. Despite the great advantages of fish models in studying vertebrate development and diseases and the tremendous interest observed in recent years, reports on apoptosis in fish are still limited. Although apoptotic machinery is well conserved between aquatic and terrestrial organisms throughout the history of evolution, some differences exist in key components of apoptotic pathways. Core parts of apoptotic machinery in fish are virtually expressed as equivalent to the mammalian models. Some differences are, however, evident, such as the extrinsic and intrinsic pathways of apoptosis including lack of a C-terminal region in the Fas-associated protein with a death domain in fish. Aquatic species inhabit a complex and highly fluctuating environment, making these species good examples to reveal features of apoptosis that may not be easily investigated in mammals. Therefore, in order to gain a wider view on programmed cell death in fish, interactions between the main environmental factors, chemicals and apoptosis are discussed in this review. It is indicated that apoptosis can be induced in fish by exposure to environmental stressors during different stages of the fish life cycle.

Phenethyl Isothiocyanate Induces Apoptotic Cell Death Through the Mitochondria-dependent Pathway in Gefitinib-resistant NCI-H460 Human Lung Cancer Cells In Vitro.

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Hsia, Te-Chun; Huang, Yi-Ping; Jiang, Yi-Wen; Chen, Hsin-Yu; Cheng, Zheng-Yu; Hsiao, Yung-Ting; Chen, Cheng-Yen; Peng, Shu-Fen; Chueh, Fu-Shin; Chou, Yu-Cheng; Chung, Jing-Gung

2018-04-01

Some lung cancer patients treated with gefitinib develop resistance to this drug resulting in unsatisfactory treatment outcomes. Phenethyl isothiocyanate (PEITC), present in our common cruciferous vegetables, exhibits anticancer activities in many human cancer cell lines. Currently, there is no available information on the possible modification of gefitinib resistance of lung cancer in vitro by PEITC. Thus, the effects of PEITC on gefitinib resistant lung cancer NCI-H460 cells were investigated in vitro. The total cell viability, apoptotic cell death, production of reactive oxygen species (ROS) and Ca 2+ , levels of mitochondria membrane potential (ΔΨ m ) and caspase-3, -8 and -9 activities were measured by flow cytometry assay. PEITC induced chromatin condensation was examined by DAPI staining. PEITC-induced cell morphological changes, decreased total viable cell number and induced apoptotic cell death in NCI-H460 and NCI-H460/G cells. PEITC decreased ROS production in NCI-H460 cells, but increased production in NCI-H460/G cells. PEITC increased Ca 2+ production, decreased the levels of ΔΨ m and increased caspase-3, -8 and -9 activities in both NCI-H460 and NCI-H460/G cells. Western blotting was used to examine the effect of apoptotic cell death associated protein expression in NCI-H460 NCI-H460/G cells after exposure to PEITC. Results showed that PEITC increased expression of cleaved caspase-3, PARP, GADD153, Endo G and pro-apoptotic protein Bax in NCI-H460/G cells. Based on these results, we suggest that PEITC induces apoptotic cell death via the caspase- and mitochondria-dependent pathway in NCI-H460/G cells. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Titanium dioxide induces apoptotic cell death through reactive oxygen species-mediated Fas upregulation and Bax activation

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Yoon TH

2012-03-01

Full Text Available Ki-Chun Yoo1, Chang-Hwan Yoon1, Dongwook Kwon2, Kyung-Hwan Hyun1, Soo Jung Woo1, Rae-Kwon Kim1, Eun-Jung Lim1, Yongjoon Suh1, Min-Jung Kim1, Tae Hyun Yoon2, Su-Jae Lee11Laboratory of Molecular Biochemistry, 2Laboratory of Nanoscale Characterization and Environmental Chemistry, Department of Chemistry, Hanyang University, Seoul, Republic of KoreaBackground: Titanium dioxide (TiO2 has been widely used in many areas, including biomedicine, cosmetics, and environmental engineering. Recently, it has become evident that some TiO2 particles have a considerable cytotoxic effect in normal human cells. However, the molecular basis for the cytotoxicity of TiO2 has yet to be defined.Methods and results: In this study, we demonstrated that combined treatment with TiO2 nanoparticles sized less than 100 nm and ultraviolet A irradiation induces apoptotic cell death through reactive oxygen species-dependent upregulation of Fas and conformational activation of Bax in normal human cells. Treatment with P25 TiO2 nanoparticles with a hydrodynamic size distribution centered around 70 nm (TiO2P25–70 together with ultraviolet A irradiation-induced caspase-dependent apoptotic cell death, accompanied by transcriptional upregulation of the death receptor, Fas, and conformational activation of Bax. In line with these results, knockdown of either Fas or Bax with specific siRNA significantly inhibited TiO2-induced apoptotic cell death. Moreover, inhibition of reactive oxygen species with an antioxidant, N-acetyl-L-cysteine, clearly suppressed upregulation of Fas, conformational activation of Bax, and subsequent apoptotic cell death in response to combination treatment using TiO2P25–70 and ultraviolet A irradiation.Conclusion: These results indicate that sub-100 nm sized TiO2 treatment under ultraviolet A irradiation induces apoptotic cell death through reactive oxygen species-mediated upregulation of the death receptor, Fas, and activation of the preapoptotic protein

Corn silk maysin induces apoptotic cell death in PC-3 prostate cancer cells via mitochondria-dependent pathway.

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Lee, Jisun; Lee, Seul; Kim, Sun-Lim; Choi, Ji Won; Seo, Jeong Yeon; Choi, Doo Jin; Park, Yong Il

2014-12-05

Despite recent advances in prostate cancer diagnostics and therapeutics, the overall survival rate still remains low. This study was aimed to assess potential anti-cancer activity of maysin, a major flavonoid of corn silk (CS, Zea mays L.), in androgen-independent human prostate cancer cells (PC-3). Maysin was isolated from CS of Kwangpyeongok, a Korean hybrid corn, via methanol extraction and preparative C18 reverse phase column chromatography. Maysin cytotoxicity was determined by either monitoring cell viability in various cancer cell lines by MTT assay or morphological changes. Apoptotic cell death was assessed by annexin V-FITC/PI double staining, depolarization of mitochondrial membrane potential (MMP), expression levels of Bcl-2 and pro-caspase-3 and by terminal transferase mediated dUTP-fluorescein nick end labeling (TUNEL) staining. Underlying mechanism in maysin-induced apoptosis of PC-3 cells was explored by evaluating its effects on Akt and ERK pathway. Maysin dose-dependently reduced the PC-3 cell viability, with an 87% reduction at 200 μg/ml. Maysin treatment significantly induced apoptotic cell death, DNA fragmentation, depolarization of MMP, and reduction in Bcl-2 and pro-caspase-3 expression levels. Maysin also significantly attenuated phosphorylation of Akt and ERK. A combined treatment with maysin and other known anti-cancer agents, including 5-FU, etoposide, cisplatin, or camptothecin, synergistically enhanced PC-3 cell death. These results suggested for the first time that maysin inhibits the PC-3 cancer cell growth via stimulation of mitochondria-dependent apoptotic cell death and may have a strong therapeutic potential for the treatment of either chemo-resistant or androgen-independent human prostate cancer. Copyright © 2014 Elsevier Inc. All rights reserved.

Nitric oxide and calcium ions in apoptotic esophageal carcinoma cells induced by arsenite

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Shen, Zhong-Ying; Shen, Wen-Ying; Chen, Ming-Hua; Shen, Jian; Cai, Wei-Jie; Yi, Zeng

2002-01-01

AIM: To Quantitatively analyze the nitri oxide (NO) and Ca2+ in apoptosis of esophageal carcinoma cells induced by arsenic trioxide (As2O3). METHODS: The cell line SHEEC1, a malignant esophageal epithelial cell induced by HPV in synergy with TPA in our laboratory, was cultured in a serum-free medium and treated with As2O3. Before and after administration of As2O3, NO production in cultured medium was detected quantitatively using the Griess Colorimetric method. Intracellular Ca2+ was labeled by using the fluorescent dye Fluo3-AM and detected under confocal laser scanning microscope (CLSM), which was able to acquire data in real-time enabling Ca2+ dynamics of individual cells in vitro. The apoptotic cells were examined under electron microscopy. RESULTS: Intracellular concentration of Ca2+ increased from 1.00 units to 1.09-1.38 units of fluorescent intensity at As2O3 treatment and NO products subsequently released from As2O3-treated cells increased from 0.98-1.00 × 10-2 μmol·L-1 up to 1.48-1.52 × 10-2 μmol·L-1 and maintained in a high level continuously. Finally apoptosis of cells occurred, chromatin being agglutinated, cells shrunk, nuclei became round and mitochondria swelled. CONCLUSION: Ca2+ and NO increased with cell damage and apoptosis in cells treated by As2O3. The Ca2+ is an initial messenger to the apoptotic pathway. To investigate Ca2+ and NO will be a new direction for studying the apoptotic signaling messenger of the esophageal carcinoma cells induced by As2O3. PMID:11833068

Neuroprotective effects of corn silk maysin via inhibition of H2O2-induced apoptotic cell death in SK-N-MC cells.

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Choi, Doo Jin; Kim, Sun-Lim; Choi, Ji Won; Park, Yong Il

2014-07-25

Neuroprotective effects of maysin, which is a flavone glycoside that was isolated from the corn silk (CS, Zea mays L.) of a Korean hybrid corn Kwangpyeongok, against oxidative stress (H2O2)-induced apoptotic cell death of human neuroblastoma SK-N-MC cells were investigated. Maysin cytotoxicity was determined by measuring cell viability using MTT and lactate dehydrogenase (LDH) assays. Intracellular reactive oxygen species (ROS) were measured using a 2,7-dichlorofluorescein diacetate (DCF-DA) assay. Apoptotic cell death was monitored by annexin V-FITC/PI double staining and by a TUNEL assay. Antioxidant enzyme mRNA levels were determined by real-time PCR. The cleavage of poly (ADP-ribose) polymerase (PARP) was measured by western blotting. Maysin pretreatment reduced the cytotoxic effect of H2O2 on SK-N-MC cells, as shown by the increase in cell viability and by reduced LDH release. Maysin pretreatment also dose-dependently reduced the intracellular ROS level and inhibited PARP cleavage. In addition, DNA damage and H2O2-induced apoptotic cell death were significantly attenuated by maysin pretreatment. Moreover, maysin pretreatment (5-50 μg/ml) for 2h significantly and dose-dependently increased the mRNA levels of antioxidant enzymes (CAT, GPx-1, SOD-1, SOD-2 and HO-1) in H2O2 (200 μM)-insulted cells. These results suggest that CS maysin has neuroprotective effects against oxidative stress (H2O2)-induced apoptotic death of human brain SK-N-MC cells through its antioxidative action. This report is the first regarding neuroprotective health benefits of corn silk maysin by its anti-apoptotic action and by triggering the expression of intracellular antioxidant enzyme systems in SK-N-MC cells. Copyright © 2014 Elsevier Inc. All rights reserved.

ROS-mediated apoptotic cell death in prostate cancer LNCaP cells induced by biosurfactant stabilized CdS quantum dots.

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Singh, Braj R; Singh, Brahma N; Khan, W; Singh, H B; Naqvi, A H

2012-08-01

Cadmium sulfide (CdS) quantum dots (QDs) have raised great attention because of their superior optical properties and wide utilization in biological and biomedical studies. However, little is known about the cell death mechanisms of CdS QDs in human cancer cells. This study was designed to investigate the possible mechanisms of apoptosis induced by biosurfactant stabilized CdS QDs (denoted as "bsCdS QDs") in human prostate cancer LNCaP cells. It was also noteworthy that apoptosis correlated with reactive oxygen species (ROS) production, mitochondrial damage, oxidative stress and chromatin condensation in a dose- and time-dependent manner. Results also showed involvement of caspases, Bcl-2 family proteins, heat shock protein 70, and a cell-cycle checkpoint protein p53 in apoptosis induction by bsCdS QDs in LNCaP cells. Moreover, pro-apoptotic protein Bax was upregulated and the anti-apoptotic proteins, survivin and NF-κB were downregulated in bsCdS QDs exposed cells. Protection of N-acetyl cysteine (NAC) against ROS clearly suggested the implication of ROS in hyper-activation of apoptosis and cell death. It is encouraging to conclude that biologically stabilized CdS QDs bear the potential of its applications in biomedicine, such as tumor therapy specifically by inducing caspase-dependent apoptotic cell death of human prostate cancer LNCaP cells. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

Manganese induces mitochondrial dynamics impairment and apoptotic cell death: a study in human Gli36 cells.

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Alaimo, Agustina; Gorojod, Roxana M; Miglietta, Esteban A; Villarreal, Alejandro; Ramos, Alberto J; Kotler, Mónica L

2013-10-25

Manganese (Mn) is an essential trace element due to its participation in many physiological processes. However, overexposure to this metal leads to a neurological disorder known as Manganism whose clinical manifestations and molecular mechanisms resemble Parkinson's disease. Several lines of evidence implicate astrocytes as an early target of Mn neurotoxicity being the mitochondria the most affected organelles. The aim of this study was to investigate the possible mitochondrial dynamics alterations in Mn-exposed human astrocytes. Therefore, we employed Gli36 cells which express the astrocytic markers GFAP and S100B. We demonstrated that Mn triggers the mitochondrial apoptotic pathway revealed by increased Bax/Bcl-2 ratio, by the loss of mitochondrial membrane potential and by caspase-9 activation. This apoptotic program may be in turn responsible of caspase-3/7 activation, PARP-1 cleavage, chromatin condensation and fragmentation. In addition, we determined that Mn induces deregulation in mitochondria-shaping proteins (Opa-1, Mfn-2 and Drp-1) expression levels in parallel with the disruption of the mitochondrial network toward to an exacerbated fragmentation. Since mitochondrial dynamics is altered in several neurodegenerative diseases, these proteins could become future targets to be considered in Manganism treatment. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Orphan Nuclear Receptor NR4A1 Binds a Novel Protein Interaction Site on Anti-apoptotic B Cell Lymphoma Gene 2 Family Proteins.

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Godoi, Paulo H C; Wilkie-Grantham, Rachel P; Hishiki, Asami; Sano, Renata; Matsuzawa, Yasuko; Yanagi, Hiroko; Munte, Claudia E; Chen, Ya; Yao, Yong; Marassi, Francesca M; Kalbitzer, Hans R; Matsuzawa, Shu-Ichi; Reed, John C

2016-07-01

B cell lymphoma gene 2 (Bcl-2) family proteins are key regulators of programmed cell death and important targets for drug discovery. Pro-apoptotic and anti-apoptotic Bcl-2 family proteins reciprocally modulate their activities in large part through protein interactions involving a motif known as BH3 (Bcl-2 homology 3). Nur77 is an orphan member of the nuclear receptor family that lacks a BH3 domain but nevertheless binds certain anti-apoptotic Bcl-2 family proteins (Bcl-2, Bfl-1, and Bcl-B), modulating their effects on apoptosis and autophagy. We used a combination of NMR spectroscopy-based methods, mutagenesis, and functional studies to define the interaction site of a Nur77 peptide on anti-apoptotic Bcl-2 family proteins and reveal a novel interaction surface. Nur77 binds adjacent to the BH3 peptide-binding crevice, suggesting the possibility of cross-talk between these discrete binding sites. Mutagenesis of residues lining the identified interaction site on Bcl-B negated the interaction with Nur77 protein in cells and prevented Nur77-mediated modulation of apoptosis and autophagy. The findings establish a new protein interaction site with the potential to modulate the apoptosis and autophagy mechanisms governed by Bcl-2 family proteins. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Cross-talk between miR-471-5p and autophagy component proteins regulates LC3-associated phagocytosis (LAP) of apoptotic germ cells.

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Panneerdoss, Subbarayalu; Viswanadhapalli, Suryavathi; Abdelfattah, Nourhan; Onyeagucha, Benjamin C; Timilsina, Santosh; Mohammad, Tabrez A; Chen, Yidong; Drake, Michael; Vuori, Kristiina; Kumar, T Rajendra; Rao, Manjeet K

2017-09-19

Phagocytic clearance of apoptotic germ cells by Sertoli cells is vital for germ cell development and differentiation. Here, using a tissue-specific miRNA transgenic mouse model, we show that interaction between miR-471-5p and autophagy member proteins regulates clearance of apoptotic germ cells via LC3-associated phagocytosis (LAP). Transgenic mice expressing miR-471-5p in Sertoli cells show increased germ cell apoptosis and compromised male fertility. Those effects are due to defective engulfment and impaired LAP-mediated clearance of apoptotic germ cells as miR-471-5p transgenic mice show lower levels of Dock180, LC3, Atg12, Becn1, Rab5 and Rubicon in Sertoli cells. Our results reveal that Dock180 interacts with autophagy member proteins to constitute a functional LC3-dependent phagocytic complex. We find that androgen regulates Sertoli cell phagocytosis by controlling expression of miR-471-5p and its target proteins. These findings suggest that recruitment of autophagy machinery is essential for efficient clearance of apoptotic germ cells by Sertoli cells using LAP.Although phagocytic clearance of apoptotic germ cells by Sertoli cells is essential for spermatogenesis, little of the mechanism is known. Here the authors show that Sertoli cells employ LC3-associated phagocytosis (LAP) by recruiting autophagy member proteins to clear apoptotic germ cells.

Effect of Transient Maternal Hypotension on Apoptotic Cell Death in Foetal Rat Brain

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Hamit Özyürek

2014-03-01

Full Text Available Background: Intrauterine perfusion insufficiency induced by transient maternal hypotension has been reported to be associated with foetal brain malformations. However, the effects of maternal hypotension on apoptotic processes in the foetal brain have not been investigated experimentally during the intrauterine period. Aims: The aim of this study was to investigate the effects of transient maternal hypotension on apoptotic cell death in the intrauterine foetal brain. Study Design: Animal experimentation. Methods: Three-month-old female Wistar albino rats were allocated into four groups (n=5 each. The impact of hypoxic/ischemic injury induced by transient maternal hypotension on the 15th day of pregnancy (late gestation in rats was investigated at 48 (H17 group or 96 hours (H19 group after the insult. Control groups underwent the same procedure except for induction of hypotension (C17 and H17 groups. Brain sections of one randomly selected foetus from each pregnant rat were histopathologically evaluated for hypoxic/ischemic injury in the metencephalon, diencephalon, and telencephalon by terminal transferase-mediated dUTP nick end labelling and active cysteine-dependent aspartate-directed protease-3 (caspase-3 positivity for cell death. Results: The number of terminal transferase-mediated dUTP nick end labelling (+ cells in all the areas examined was comparable in both hypotension and control groups. The H17 group had active caspase-3 (+ cells in the metencephalon and telencephalon, sparing diencephalon, whereas the C19 and H19 groups had active caspase-3 (+ cells in all three regions. The number of active caspase-3 (+ cells in the telencephalon in the H19 group was higher compared with the metencephalon and diencephalon and compared with H17 group (p<0.05. Conclusion: Our results suggest that prenatal hypoxic/ischemic injury triggers apoptotic mechanisms. Therefore, blockade of apoptotic pathways, considering the time pattern of the insult, may

Methadone as an inducer of apoptotic process in cheek mucosae cells in rats

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Małgorzata Stępień

2017-11-01

Full Text Available Methadone is an opioid medication which can reduce withdrawal symptoms in people addicted to heroin and other drugs. Methadone is used also as a pain reliever and as part of drug addiction detoxification program. Apoptosis is the physiological process that plays a critical role in development and tissue homeostasis. The progress of apoptosis is regulated by signal cascades. The aim of this study was to asses how methadone induces apoptotic process in cheek mucosae cells in rats. Forty albino rats wares divided into two parts and five subgroups each. The biggest histological changes of cheek mucosae was observed in the groups with methadone. There is no indication of ability to regeneration in short time after treatment.

Long-term treatment of anterior pituitary cells with nitric oxide induces programmed cell death.

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Velardez, Miguel Omar; Poliandri, Ariel Hernán; Cabilla, Jimena Paula; Bodo, Cristian Carlos Armando; Machiavelli, Leticia Inés; Duvilanski, Beatriz Haydeé

2004-04-01

Nitric oxide (NO) plays a complex role in modulating programmed cell death. It can either protect the cell from apoptotic death or mediate apoptosis, depending on its concentration and the cell type and/or status. In this study, we demonstrate that long-term exposition to NO induces cell death of anterior pituitary cells from Wistar female rats. DETA NONOate (Z)-1-[2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate, 1 mm], a NO donor that releases NO for an extended period of time, decreased cellular viability and prolactin release from primary cultures of anterior pituitary cells. Morphological studies showed an increase in the number of cells with chromatin condensation and nuclear fragmentation at 24 and 48 h after DETA/NO exposure. DNA internucleosomal fragmentation was also observed at the same time. Reversibility of the NO effect on cellular viability and prolactin release was observed only when the cells were incubated with DETA/NO for less than 6 h. Most apoptotic cells were immunopositive for prolactin, suggesting a high susceptibility of lactotrophs to the effect of NO. The cytotoxic effect of NO is dependent of caspase-9 and caspase-3, but seems to be independent of oxidative stress or nitrosative stress. Our results show that the exposition of anterior pituitary cells to NO for long periods induces programmed cell death of anterior pituitary cells.

Anti-Proliferative and Apoptotic Effects of Beta-Ionone in Human Leukemia Cell Line K562

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Zohreh Faezizadeh

2016-06-01

Full Text Available Background Beta-ionone is an aroma compound found in the Rosaceae family. Some evidence supported that beta-ionone has a great potential for cancer prevention. To date, the anti-proliferative and apoptotic effects of beta-ionone in human leukemia cell line K562 were not studied. Objectives Hence, we investigated whether beta-ionone could inhibit cell growth and induce apoptosis in the K562 cells. Materials and Methods In this experimental study, human leukemia cell line K562 was cultured and anti-proliferation effect of beta-ionone with different doses (25 - 400 µm at different times (24 - 96 hours on treated cells was evaluated by the MTT assay. To determine apoptosis rate, the Hoechst 33342 staining and flow cytometry was performed. Results The MTT assay showed that beta-ionone inhibited proliferation of K562 cells in a dose-dependent manner significantly (P = 0.0008. Moreover, the increased apoptotic rate was found after incubation of K562 cells with 200 µm beta-ionone. The Hoechst staining and flow cytometry analysis indicated that beta-ionone could increase apoptosis of K562 cells in a dose-dependent manner. Conclusions The results demonstrated that beta-ionone has anti-proliferative and apoptotic effects on K562 cells, and in the future may be used in the treatment of some leukemia sub-types.

Association of anti-apoptotic Mcl-1L isoform expression with radioresistance of oral squamous carcinoma cells

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Palve, Vinayak C; Teni, Tanuja R

2012-01-01

Oral cancer is a common cancer and a major health problem in the Indian subcontinent. At our laboratory Mcl-1, an anti-apoptotic member of the Bcl-2 family has been demonstrated to be overexpressed in oral cancers and to predict outcome in oral cancer patients treated with definitive radiotherapy. To study the role of Mcl-1 isoforms in radiation response of oral squamous carcinoma cells (OSCC), we investigated in the present study, the association of Mcl-1 isoform expression with radiosensitivity of OSCC, using siRNA strategy. The time course expression of Mcl-1 splice variants (Mcl-1L, Mcl-1S & Mcl-1ES) was studied by RT-PCR, western blotting & immunofluorescence, post-irradiation in oral cell lines [immortalized FBM (radiosensitive) and tongue cancer AW8507 & AW13516 (radioresistant)]of relatively differing radiosensitivities. The effect of Mcl-1L knockdown alone or in combination with ionizing radiation (IR) on cell proliferation, apoptosis & clonogenic survival, was investigated in AW8507 & AW13516 cells. Further the expression of Mcl-1L protein was assessed in radioresistant sublines generated by fractionated ionizing radiation (FIR). Three to six fold higher expression of anti-apoptotic Mcl-1L versus pro-apoptotic Mcl-1S was observed at mRNA & protein levels in all cell lines, post-irradiation. Sustained high levels of Mcl-1L, downregulation of pro-apoptotic Bax & Bak and a significant (P < 0.05) reduction in apoptosis was observed in the more radioresistant AW8507, AW13516 versus FBM cells, post-IR. The ratios of anti to pro-apoptotic proteins were high in AW8507 as compared to FBM. Treatment with Mcl-1L siRNA alone or in combination with IR significantly (P < 0.01) increased apoptosis viz. 17.3% (IR), 25.3% (siRNA) and 46.3% (IR plus siRNA) and upregulated pro-apoptotic Bax levels in AW8507 cells. Combination of siRNA & IR treatment significantly (P < 0.05) reduced cell proliferation and clonogenic survival of radioresistant AW8507 & AW13516 cells

Expression of defender against apoptotic death (DAD-1) in iris and dianthus petals

NARCIS (Netherlands)

Kop, van der D.A.M.; Ruys, G.; Dees, D.; Schoot, van der C.; Boer, de A.D.; Doorn, van W.G.

2003-01-01

The gene defender against apoptotic death (DAD-1) prevents programmed cell death in animal cells. We investigated the expression pattern of DAD-1 in petals of iris (Iris x hollandica cv. Blue Magic) and carnation (Dianthus caryophyllus cv. Etarro). DAD-1 expression in Iris petals was strongly

Lactadherin inhibits secretory phospholipase A2 activity on pre-apoptotic leukemia cells.

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Steffen Nyegaard

Full Text Available Secretory phospholipase A2 (sPLA2 is a critical component of insect and snake venoms and is secreted by mammalian leukocytes during inflammation. Elevated secretory PLA2 concentrations are associated with autoimmune diseases and septic shock. Many sPLA2's do not bind to plasma membranes of quiescent cells but bind and digest phospholipids on the membranes of stimulated or apoptotic cells. The capacity of these phospholipases to digest membranes of stimulated or apoptotic cells correlates to the exposure of phosphatidylserine. In the present study, the ability of the phosphatidyl-L-serine-binding protein, lactadherin to inhibit phospholipase enzyme activity has been assessed. Inhibition of human secretory phospholipase A2-V on phospholipid vesicles exceeded 90%, whereas inhibition of Naja mossambica sPLA2 plateaued at 50-60%. Lactadherin inhibited 45% of activity of Naja mossambica sPLA2 and >70% of human secretory phospholipase A2-V on the membranes of human NB4 leukemia cells treated with calcium ionophore A23187. The data indicate that lactadherin may decrease inflammation by inhibiting sPLA2.

Apoptotic-cell-derived membrane microparticles and IFN-α induce an inflammatory immune response.

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Niessen, Anna; Heyder, Petra; Krienke, Stefan; Blank, Norbert; Tykocinski, Lars-Oliver; Lorenz, Hanns-Martin; Schiller, Martin

2015-07-15

A dysregulation in the clearance of apoptotic material is considered a major pathogenetic factor for the emergence of autoimmune diseases. Apoptotic-cell-derived membrane microparticles (AdMPs), which are released from the cell surface during apoptosis, have been implicated in the pathogenesis of autoimmunity. Also of importance are cytokines, such as interferon-α (IFN-α), which is known to be a major player in patients with systemic lupus erythematosus (SLE). This study investigates the combined effect of AdMPs and IFN-α on professional phagocytes. In the presence of IFN-α, phagocytosis of AdMPs by human monocytes was significantly increased in a dose-dependent manner. The combination of AdMPs and raised IFN-α concentrations resulted in an increase in the secretion of pro-inflammatory cytokines and an upregulation of surface molecule expression involved in antigen uptake. In addition, macrophage polarisation was shifted towards a more inflammatory type of cell. The synergism between IFN-α and AdMPs seemed to be mediated by an upregulation of phosphorylated STAT1. Our results indicate that IFN-α, together with AdMPs, amplify the initiation and maintenance of inflammation. This mechanism might especially play a crucial role in disorders with a defective clearance of apoptotic material. © 2015. Published by The Company of Biologists Ltd.

A study on apoptotic signaling pathway in HL-60 cells induced by radiation

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Kim, Hye Jung; Moon, Sung Keun; Lee, Jae Hoon; Moon, Sun Rock

2001-01-01

The mechanical insights of death at cancer cells by ionizing radiation are not yet clearly defined. Recent evidences have demonstrated that radiation therapy may induce cell death via activation of signaling pathway for apoptosis in target cells. This study is designed whether ionizing radiation may activate the signaling cascades of apoptosis including caspase family cysteine proteases, Bcl2/Bax, cytochrome c and Fas/Fas-L in target cells. HL-60 cells were irradiated in vitro with 6 MV X-ray at dose ranges from 2 Gy to 32 Gy. The cell viability was tested by MTT assay and the extent of apoptosis was determined using agarose gel electrophoresis. The activities of caspase proteases were measured by proteolytic cleavages of substrates. Western blot analysis was used to monitor PARP, caspase-3, Cytochrome-c, BcI-2, Bax, Fas and Fas-L. Ionizing radiation decreases the viability of HL -60 cells in a time and dose dependent manner. Ionizing radiation-induced death in HL- 60 cells is an apoptotic death which is revealed as characteristic ladder-pattern fragmentation at genomic DNA over 16 Gy at 4 hours. Ionizing radiation induces the activation of caspase-2, 3, 6, 8 and 9 of HL --60 cells in a time-dependent manner. The activation of caspase- 3 protease is also evidenced by the digestion of poly (ADP-ribose) polymerase and procaspase 3 with 16Gy ionizing irradiation. Anti-apoptotic Bcl2 expression is decreased but apoptotic Bax expression is increased with mitochondrial cytochrome c release in a time- dependent manner. In addition, expression of Fas and Fas-L is also increased in a time dependent manner. These data suggest that ionizing radiation-induced apoptosis is mediated by the activation of various signaling pathways including caspase family cysteine proteases, BcI 2 /Bax, Fas and Fas-L in a time and dose dependent manner

Phosphatidylserine-Liposomes Promote Tolerogenic Features on Dendritic Cells in Human Type 1 Diabetes by Apoptotic Mimicry

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Silvia Rodriguez-Fernandez

2018-02-01

Full Text Available Type 1 diabetes (T1D is a metabolic disease caused by the autoimmune destruction of insulin-producing β-cells. With its incidence increasing worldwide, to find a safe approach to permanently cease autoimmunity and allow β-cell recovery has become vital. Relying on the inherent ability of apoptotic cells to induce immunological tolerance, we demonstrated that liposomes mimicking apoptotic β-cells arrested autoimmunity to β-cells and prevented experimental T1D through tolerogenic dendritic cell (DC generation. These liposomes contained phosphatidylserine (PS—the main signal of the apoptotic cell membrane—and β-cell autoantigens. To move toward a clinical application, PS-liposomes with optimum size and composition for phagocytosis were loaded with human insulin peptides and tested on DCs from patients with T1D and control age-related subjects. PS accelerated phagocytosis of liposomes with a dynamic typical of apoptotic cell clearance, preserving DCs viability. After PS-liposomes phagocytosis, the expression pattern of molecules involved in efferocytosis, antigen presentation, immunoregulation, and activation in DCs concurred with a tolerogenic functionality, both in patients and control subjects. Furthermore, DCs exposed to PS-liposomes displayed decreased ability to stimulate autologous T cell proliferation. Moreover, transcriptional changes in DCs from patients with T1D after PS-liposomes phagocytosis pointed to an immunoregulatory prolife. Bioinformatics analysis showed 233 differentially expressed genes. Genes involved in antigen presentation were downregulated, whereas genes pertaining to tolerogenic/anti-inflammatory pathways were mostly upregulated. In conclusion, PS-liposomes phagocytosis mimics efferocytosis and leads to phenotypic and functional changes in human DCs, which are accountable for tolerance induction. The herein reported results reinforce the potential of this novel immunotherapy to re-establish immunological

The TAM-family receptor Mer mediates production of HGF through the RhoA-dependent pathway in response to apoptotic cells.

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Park, Hyun-Jung; Baen, Ji-Yeon; Lee, Ye-Ji; Choi, Youn-Hee; Kang, Jihee Lee

2012-08-01

The TAM receptor protein tyrosine kinases Tyro3, Axl, and Mer play important roles in macrophage function. We investigated the roles of the TAM receptors in mediating the induction of hepatocyte growth factor (HGF) during the interaction of macrophages with apoptotic cells. Mer-specific neutralizing antibody, small interfering RNA (siRNA), and a recombinant Mer protein (Mer/Fc) inhibited HGF mRNA and protein expression, as well as activation of RhoA, Akt, and specific mitogen-activated protein (MAP) kinases in response to apoptotic cells. Inhibition of Axl or Tyro3 with specific antibodies, siRNA, or Fc-fusion proteins did not prevent apoptotic cell-induced HGF mRNA and protein expression and did not inhibit activation of the postreceptor signaling molecules RhoA and certain MAP kinases, including extracellular signal-regulated protein kinase and c-Jun NH(2)-terminal kinase. However, Axl- and Tyro3-specific blockers did inhibit the activation of Akt and p38 MAP kinase in response to apoptotic cells. In addition, none of the TAM receptors mediated the effects of apoptotic cells on transforming growth factor-β or epidermal growth factor mRNA expression. However, they were involved in the induction of vascular endothelial growth factor mRNA expression. Our data provide evidence that when macrophages interact with apoptotic cells, only Mer of the TAM-family receptors is responsible for mediating transcriptional HGF production through a RhoA-dependent pathway.

Histochemical detection and comparison of apoptotic cells in the gingival epithelium using hematoxylin and eosin and methyl green-pyronin: A pilot study.

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Nayak, Aarati; Raikar, Anita; Kotrashetti, Vijaylaxmi; Nayak, Ramakant; Shree, Sumedha; Kambali, Soumya

2016-01-01

Apoptosis plays a critical role in the regulation of inflammation and host immune response. It helps in tissue homeostasis and a disturbance in this is often associated with disease. The use of histochemical stains like hematoxylin and eosin (H and E) and methyl green-pyronin (MGP) can provide a simple and cost-effective method for the detection of apoptotic cells. Study intended to analyze the expression of apoptosis in the gingival epithelium of healthy subjects and in patients with chronic periodontitis, using H and E and MGP. It is also proposed to correlate the apoptotic index (AI) of healthy individuals and those with chronic periodontitis. Twenty gingival biopsies were harvested from which ten samples were of healthy subjects and ten subjects who suffered from chronic periodontitis. Apoptotic cells were analyzed using MGP and H and E under light microscopy. Apoptotic cells were identified at ×100 magnification and AI was calculated. Apoptotic cells were easily distinguishable in MGP stained sections when compared to those stained using H and E. Moreover, apoptotic cell count was higher in chronic periodontitis. Statistical analyses were done by Tukey's multiple post hoc procedure. The study reveals that MGP staining can be used in a routine basic laboratory set up as one of the cost-effective methods for the detection of apoptotic cells.

Histochemical detection and comparison of apoptotic cells in the gingival epithelium using hematoxylin and eosin and methyl green-pyronin: A pilot study

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Aarati Nayak

2016-01-01

Full Text Available Background: Apoptosis plays a critical role in the regulation of inflammation and host immune response. It helps in tissue homeostasis and a disturbance in this is often associated with disease. The use of histochemical stains like hematoxylin and eosin (H and E and methyl green-pyronin (MGP can provide a simple and cost-effective method for the detection of apoptotic cells. Aim: Study intended to analyze the expression of apoptosis in the gingival epithelium of healthy subjects and in patients with chronic periodontitis, using H and E and MGP. It is also proposed to correlate the apoptotic index (AI of healthy individuals and those with chronic periodontitis. Materials and Methods: Twenty gingival biopsies were harvested from which ten samples were of healthy subjects and ten subjects who suffered from chronic periodontitis. Apoptotic cells were analyzed using MGP and H and E under light microscopy. Results: Apoptotic cells were identified at ×100 magnification and AI was calculated. Apoptotic cells were easily distinguishable in MGP stained sections when compared to those stained using H and E. Moreover, apoptotic cell count was higher in chronic periodontitis. Statistical analyses were done by Tukey's multiple post hoc procedure. Conclusion: The study reveals that MGP staining can be used in a routine basic laboratory set up as one of the cost-effective methods for the detection of apoptotic cells.

De-novo NAD+ synthesis regulates SIRT1-FOXO1 apoptotic pathway in response to NQO1 substrates in lung cancer cells.

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Liu, Huiying; Xing, Rong; Cheng, Xuefang; Li, Qingran; Liu, Fang; Ye, Hui; Zhao, Min; Wang, Hong; Wang, Guangji; Hao, Haiping

2016-09-20

Tryptophan metabolism is essential in diverse kinds of tumors via regulating tumor immunology. However, the direct role of tryptophan metabolism and its signaling pathway in cancer cells remain largely elusive. Here, we establish a mechanistic link from L-type amino acid transporter 1 (LAT1) mediated transport of tryptophan and the subsequent de-novo NAD+ synthesis to SIRT1-FOXO1 regulated apoptotic signaling in A549 cells in response to NQO1 activation. In response to NQO1 activation, SIRT1 is repressed leading to the increased cellular accumulation of acetylated FOXO1 that transcriptionally activates apoptotic signaling. Decreased uptake of tryptophan due to the downregulation of LAT1 coordinates with PARP-1 hyperactivation to induce rapid depletion of NAD+ pool. Particularly, the LAT1-NAD+-SIRT1 signaling is activated in tumor tissues of patients with non-small cell lung cancer. Because NQO1 activation is characterized with oxidative challenge induced DNA damage, these results suggest that LAT1 and de-novo NAD+ synthesis in NSCLC cells may play essential roles in sensing excessive oxidative stress.

In vitro evidence for participation of DEC-205 expressed by thymic cortical epithelial cells in clearance of apoptotic thymocytes.

NARCIS (Netherlands)

Small, M; Kraal, G.

2003-01-01

Binding of apoptotic cells was compared after incubation of thymocytes with two clones of murine thymic stromal cells to which CD4(+)/CD8(+) thymocytes attach. With the BA/10, but not the BA/2, clone, thymocytes with apoptotic morphology were bound irreversibly. These tightly bound thymocytes were

Regulation of Intrinsic and Extrinsic Apoptotic Pathways in Osteosarcoma Cells Following Oleandrin Treatment.

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Ma, Yunlong; Zhu, Bin; Yong, Lei; Song, Chunyu; Liu, Xiao; Yu, Huilei; Wang, Peng; Liu, Zhongjun; Liu, Xiaoguang

2016-11-23

Our previous study has reported the anti-tumor effect of oleandrin on osteosarcoma (OS) cells. In the current study, we mainly explored its potential regulation on intrinsic and extrinsic apoptotic pathway in OS cells. Cells apoptosis, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were detected using fluorescence staining and flow cytometry. Caspase-3 activity was detected using a commercial kit. The levels of cytoplasmic cytochrome c, mitochondrial cytochrome c, bcl-2, bax, caspase-9, Fas, FasL, caspase-8 and caspase-3 were detected by Western blotting. z-VAD-fmk was applied to block both intrinsic and extrinsic apoptosis pathways, and cells apoptosis was also tested. Furthermore, we used z-LEHD-fmk and Fas blocking antibody to inhibit intrinsic and extrinsic pathways, separately, and the selectivity of oleandrin on these pathways was explored. Results showed that oleandrin induced the apoptosis of OS cells, which was accompanied by an increase in ROS and a decrease in MMP. Furthermore, cytochrome c level was reduced in mitochondria but elevated in the cytoplasm. Caspase-3 activity was enhanced by oleandrin in a concentration- and time-dependent manner. Oleandrin also down-regulated the expression of bcl-2, but up-regulated bax, caspase-9, Fas, FasL, caspase-8 and caspase-3. In addition, the suppression of both apoptotic pathways by z-VAD-fmk greatly reverted the oleandrin-induced apoptosis. Moreover, the suppression of one pathway by a corresponding inhibitor did not affect the regulation of oleandrin on another pathway. Taken together, we concluded that oleandrin induced apoptosis of OS cells via activating both intrinsic and extrinsic apoptotic pathways.

To the Large Nucleolar Bodies in Apoptotic Leukaemic Granulocytic Progenitors without Further Differentiation. Are Large Nucleoli Always Present in Proliferating Cells?

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Smetana, K; Kuželová, K; Zápotocký, M; Hrkal, Z

2017-01-01

Large nucleoli have generally been believed to be present in less differentiated and proliferating cells including the malignant ones. Such nucleoli have also been considered to be active in the biosynthetic process and major cell developmental activities. In contrast, after cytostatic treatment, apoptotic leukaemic progenitors still containing nuclei did not exhibit substantial reduction of the nucleolar size but displayed decreased nucleolar biosynthetic activity. The present study was undertaken to provide more information on the large nucleoli in spontaneously occurring apoptotic leukaemic progenitors without further differentiation. Leukaemic progenitors of established cell lineages originating from leukaemic patients represented a very convenient model for such study. Some of them exhibit morphological signs of the spontaneously occurring apoptotic process. Since such signs are expressed by nuclear and cytoplasmic morphological variability, the present study dealt with spontaneously occurring apoptotic progenitors with preserved nuclei characterized by heavy chromatin condensation and occasional fragmentation. Based of nucleolar body and nuclear maximal diameter measurements it seems to be clear that the nucleolar size in these cells was not substantially reduced, contrary to that of the nucleus. However, large nucleolar bodies in spontaneously occurring apoptotic cells were characterized by markedly reduced biosynthetic activity, as expressed by the decreased number of nucleolar transcription markers such as nucleolar fibrillar centres. In conclusion, large nucleoli may be present not only in proliferating, but also in spontaneously occurring apoptotic cells.

The role of baculovirus apoptotic suppressors in AcMNPV-mediated translation arrest in Ld652Y cells

International Nuclear Information System (INIS)

Thiem, Suzanne M.; Chejanovsky, Nor

2004-01-01

Infecting the insect cell line IPLB-Ld652Y with the baculovirus Autographa californica multinucleocapsid nucleopolyhedrovirus (AcMNPV) results in global translation arrest, which correlates with the presence of the AcMNPV apoptotic suppressor, p35. In this study, we investigated the role of apoptotic suppression on AcMNPV-induced translation arrest. Infecting cells with AcMNPV bearing nonfunctional mutant p35 did not result in global translation arrest. In contrast, global translation arrest was observed in cells infected with AcMNPV in which p35 was replaced with Opiap, Cpiap, or p49, baculovirus apoptotic suppressors that block apoptosis by different mechanisms than p35. These results indicated that suppressing apoptosis triggered translation arrest in AcMNPV-infected Ld652Y cells. Experiments using the DNA synthesis inhibitor aphidicolin and temperature shift experiments, using the AcMNPV replication mutants ts8 and ts8Δp35, indicated that translation arrest initiated during the early phase of infection, but events during the late phase were required for global translation arrest. Peptide caspase inhibitors could not substitute for baculovirus apoptotic suppressors to induce translation arrest in Ld652Y cells infected with a p35-null virus. However, if the p35-null-AcMNPV also carried hrf-1, a novel baculovirus host range gene, progeny virus was produced and treatment with peptide caspase inhibitors enhanced translation of a late viral gene transcript. Together, these results indicate that translation arrest in AcMNPV-infected Ld652Y cells is due to the anti-apoptotic function of p35, but suggests that rather than simply preventing caspase activation, its activity enhances signaling to a separate translation arrest pathway, possibly by stimulating the late stages of the baculovirus infection cycle

Reactive oxygen species induced by Streptococcus pyogenes invasion trigger apoptotic cell death in infected epithelial cells.

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Aikawa, Chihiro; Nozawa, Takashi; Maruyama, Fumito; Tsumoto, Kohei; Hamada, Shigeyuki; Nakagawa, Ichiro

2010-06-01

Streptococcus pyogenes (group A streptococcus, GAS), one of the most common pathogens of humans, attaches and invades into human pharyngeal or skin epithelial cells. We have previously reported that induction of apoptosis is associated with GAS invasion, which induces mitochondrial dysfunction and apoptotic cell death. We demonstrate here that GAS-induced apoptosis is mediated by reactive oxygen species (ROS) production. Both the induction of apoptosis and ROS production markedly increased upon invasion of wild-type GAS strain JRS4 into HeLa cells; however, the apoptotic response was not observed in fibronectin-binding protein F1-disrupted mutant SAM1-infected cells. In Bcl-2-overexpressing HeLa cells (HBD98-2-4), the induction of apoptosis, ROS production and mitochondrial dysfunction were significantly suppressed, whereas the numbers of invaded GAS was not different between HeLa (mock cells) and the HeLa HBD98-2-4 cells. Whereas Rac1 activation occurred during GAS invasion, ROS production in GAS-infected cells was clearly inhibited by transfection with the Rac1 mutants (L37 or V12L37), but not by the dominant active mutant (V12L61) or by the dominant negative mutant (N17). These observations indicate that GAS invasion triggers ROS production through Rac1 activation and generated ROS induced mitochondrial dysfunction leading to cellular apoptosis.

Both the caspase CSP-1 and a caspase-independent pathway promote programmed cell death in parallel to the canonical pathway for apoptosis in Caenorhabditis elegans.

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Daniel P Denning

Full Text Available Caspases are cysteine proteases that can drive apoptosis in metazoans and have critical functions in the elimination of cells during development, the maintenance of tissue homeostasis, and responses to cellular damage. Although a growing body of research suggests that programmed cell death can occur in the absence of caspases, mammalian studies of caspase-independent apoptosis are confounded by the existence of at least seven caspase homologs that can function redundantly to promote cell death. Caspase-independent programmed cell death is also thought to occur in the invertebrate nematode Caenorhabditis elegans. The C. elegans genome contains four caspase genes (ced-3, csp-1, csp-2, and csp-3, of which only ced-3 has been demonstrated to promote apoptosis. Here, we show that CSP-1 is a pro-apoptotic caspase that promotes programmed cell death in a subset of cells fated to die during C. elegans embryogenesis. csp-1 is expressed robustly in late pachytene nuclei of the germline and is required maternally for its role in embryonic programmed cell deaths. Unlike CED-3, CSP-1 is not regulated by the APAF-1 homolog CED-4 or the BCL-2 homolog CED-9, revealing that csp-1 functions independently of the canonical genetic pathway for apoptosis. Previously we demonstrated that embryos lacking all four caspases can eliminate cells through an extrusion mechanism and that these cells are apoptotic. Extruded cells differ from cells that normally undergo programmed cell death not only by being extruded but also by not being engulfed by neighboring cells. In this study, we identify in csp-3; csp-1; csp-2 ced-3 quadruple mutants apoptotic cell corpses that fully resemble wild-type cell corpses: these caspase-deficient cell corpses are morphologically apoptotic, are not extruded, and are internalized by engulfing cells. We conclude that both caspase-dependent and caspase-independent pathways promote apoptotic programmed cell death and the phagocytosis of cell

SIGN-R1 and complement factors are involved in the systemic clearance of radiation-induced apoptotic cells in whole-body irradiated mice

International Nuclear Information System (INIS)

Park, Jin-Yeon; Loh, SoHee; Cho, Eun-hee; Choi, Hyeong-Jwa; Na, Tae-Young; Nemeno, Judee Grace E.; Lee, Jeong Ik; Yoon, Taek Joon; Choi, In-Soo; Lee, Minyoung; Lee, Jae-Seon; Kang, Young-Sun

2015-01-01

Although SIGN-R1-mediated complement activation pathway has been shown to enhance the systemic clearance of apoptotic cells, the role of SIGN-R1 in the clearance of radiation-induced apoptotic cells has not been characterized and was investigated in this study. Our data indicated that whole-body γ-irradiation of mice increased caspase-3 + apoptotic lymphocyte numbers in secondary lymphoid organs. Following γ-irradiation, SIGN-R1 and complements (C4 and C3) were simultaneously increased only in the mice spleen tissue among the assessed tissues. In particular, C3 was exclusively activated in the spleen. The delayed clearance of apoptotic cells was markedly prevalent in the spleen and liver of SIGN-R1 KO mice, followed by a significant increase of CD11b + cells. These results indicate that SIGN-R1 and complement factors play an important role in the systemic clearance of radiation-induced apoptotic innate immune cells to maintain tissue homeostasis after γ-irradiation. - Highlights: • Splenic SIGN-R1 + macrophages are activated after γ-irradiation. • C3 and C4 levels increased and C3 was activated in the spleen after γ-irradiation. • SIGN-R1 mediated the systemic clearance of radiation-induced apoptotic cells in spleen and liver

SIGN-R1 and complement factors are involved in the systemic clearance of radiation-induced apoptotic cells in whole-body irradiated mice

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Park, Jin-Yeon; Loh, SoHee; Cho, Eun-hee [Department of Biomedical Science & Technology, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, 143-701 (Korea, Republic of); Choi, Hyeong-Jwa [Division of Radiation Effect, Korea Institute of Radiological and Medical Sciences, 215-4, 75 Nowon gil Nowon-Gu, Seoul, 139-706 (Korea, Republic of); Na, Tae-Young [College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-741 (Korea, Republic of); Nemeno, Judee Grace E.; Lee, Jeong Ik [Regenerative Medicine Laboratory, Department of Veterinary Medicine, College of Veterinary Medicine, Konkuk University, Seoul, 143-701 (Korea, Republic of); Yoon, Taek Joon [Department of Food and Nutrition, Yuhan College, Bucheon, Gyeonggi-do, 422-749 (Korea, Republic of); Choi, In-Soo [Department of Infectious Diseases, College of Veterinary Medicine, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, 143-701 (Korea, Republic of); Lee, Minyoung [Division of Radiation Effect, Korea Institute of Radiological and Medical Sciences, 215-4, 75 Nowon gil Nowon-Gu, Seoul, 139-706 (Korea, Republic of); Lee, Jae-Seon [Department of Biomedical Sciences, College of Medicine, Inha University, Incheon, 400-712 (Korea, Republic of); Kang, Young-Sun, E-mail: kangys1967@naver.com [Department of Biomedical Science & Technology, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, 143-701 (Korea, Republic of); Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, 143-701 (Korea, Republic of)

2015-08-07

Although SIGN-R1-mediated complement activation pathway has been shown to enhance the systemic clearance of apoptotic cells, the role of SIGN-R1 in the clearance of radiation-induced apoptotic cells has not been characterized and was investigated in this study. Our data indicated that whole-body γ-irradiation of mice increased caspase-3{sup +} apoptotic lymphocyte numbers in secondary lymphoid organs. Following γ-irradiation, SIGN-R1 and complements (C4 and C3) were simultaneously increased only in the mice spleen tissue among the assessed tissues. In particular, C3 was exclusively activated in the spleen. The delayed clearance of apoptotic cells was markedly prevalent in the spleen and liver of SIGN-R1 KO mice, followed by a significant increase of CD11b{sup +} cells. These results indicate that SIGN-R1 and complement factors play an important role in the systemic clearance of radiation-induced apoptotic innate immune cells to maintain tissue homeostasis after γ-irradiation. - Highlights: • Splenic SIGN-R1{sup +} macrophages are activated after γ-irradiation. • C3 and C4 levels increased and C3 was activated in the spleen after γ-irradiation. • SIGN-R1 mediated the systemic clearance of radiation-induced apoptotic cells in spleen and liver.

Inhibition of Autophagy Potentiates Atorvastatin-Induced Apoptotic Cell Death in Human Bladder Cancer Cells in Vitro

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Kang, Minyong; Jeong, Chang Wook; Ku, Ja Hyeon; Kwak, Cheol; Kim, Hyeon Hoe

2014-01-01

Statins are cholesterol reduction agents that exhibit anti-cancer activity in several human cancers. Because autophagy is a crucial survival mechanism for cancer cells under stress conditions, cooperative inhibition of autophagy acts synergistically with other anti-cancer drugs. Thus, this study investigates whether combined treatment of atorvastatin and autophagy inhibitors results in enhancing the cytotoxic effects of atorvastatin, upon human bladder cancer cells, T24 and J82, in vitro. To measure cell viability, we performed the EZ-Cytox cell viability assay. We examined apoptosis by flow cytometry using annexin-V/propidium iodide (PI and western blot using procaspase-3 and poly (ADP-ribose) polymerase (PARP) antibodies. To examine autophagy activation, we evaluated the co-localization of LC3 and LysoTracker by immunocytochemistry, as well as the expression of LC3 and p62/sequestosome-1 (SQSTM1) by western blot. In addition, we assessed the survival and proliferation of T24 and J82 cells by a clonogenic assay. We found that atorvastatin reduced the cell viability of T24 and J82 cells via apoptotic cell death and induced autophagy activation, shown by the co-localization of LC3 and LysoTracker. Moreover, pharmacologic inhibition of autophagy significantly enhanced atorvastatin-induced apoptosis in T24 and J82 cells. In sum, inhibition of autophagy potentiates atorvastatin-induced apoptotic cell death in human bladder cancer cells in vitro, providing a potential therapeutic approach to treat bladder cancer. PMID:24815071

Human Parvovirus B19 Induced Apoptotic Bodies Contain Altered Self-Antigens that are Phagocytosed by Antigen Presenting Cells

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Thammasri, Kanoktip; Rauhamäki, Sanna; Wang, Liping; Filippou, Artemis; Kivovich, Violetta; Marjomäki, Varpu; Naides, Stanley J.; Gilbert, Leona

2013-01-01

Human parvovirus B19 (B19V) from the erythrovirus genus is known to be a pathogenic virus in humans. Prevalence of B19V infection has been reported worldwide in all seasons, with a high incidence in the spring. B19V is responsible for erythema infectiosum (fifth disease) commonly seen in children. Its other clinical presentations include arthralgia, arthritis, transient aplastic crisis, chronic anemia, congenital anemia, and hydrops fetalis. In addition, B19V infection has been reported to trigger autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. However, the mechanisms of B19V participation in autoimmunity are not fully understood. B19V induced chronic disease and persistent infection suggests B19V can serve as a model for viral host interactions and the role of viruses in the pathogenesis of autoimmune diseases. Here we investigate the involvement of B19V in the breakdown of immune tolerance. Previously, we demonstrated that the non-structural protein 1 (NS 1) of B19V induces apoptosis in non-permissive cells lines and that this protein can cleave host DNA as well as form NS1-DNA adducts. Here we provide evidence that through programmed cell death, apoptotic bodies (ApoBods) are generated by B19V NS1 expression in a non-permissive cell line. Characterization of purified ApoBods identified potential self-antigens within them. In particular, signature self-antigens such as Smith, ApoH, DNA, histone H4 and phosphatidylserine associated with autoimmunity were present in these ApoBods. In addition, when purified ApoBods were introduced to differentiated macrophages, recognition, engulfment and uptake occurred. This suggests that B19V can produce a source of self-antigens for immune cell processing. The results support our hypothesis that B19V NS1-DNA adducts, and nucleosomal and lysosomal antigens present in ApoBods created in non-permissive cell lines, are a source of self-antigens. PMID:23776709

Programmed cell death and cell extrusion in rat duodenum

DEFF Research Database (Denmark)

Schauser, Kirsten; Larsson, Lars-Inge

2005-01-01

The small intestinal epithelium is continously renewed through a balance between cell division and cell loss. How this balance is achieved is uncertain. Thus, it is unknown to what extent programmed cell death (PCD) contributes to intestinal epithelial cell loss. We have used a battery...... of techniques detecting the events associated with PCD in order to better understand its role in the turnover of the intestinal epithelium, including modified double- and triple-staining techniques for simultaneously detecting multiple markers of PCD in individual cells. Only a partial correlation between TUNEL...... positivity for DNA fragmentation, c-jun phosphorylation on serine-63, positivity for activated caspase-3 and apoptotic morphology was observed. Our results show that DNA fragmentation does not invariable correlate to activation of caspase-3. Moreover, many cells were found to activate caspase-3 early...

Preparation of anastrozole loaded PEG-PLA nanoparticles: evaluation of apoptotic response of breast cancer cell lines.

Science.gov (United States)

Alyafee, Yusra A; Alaamery, Manal; Bawazeer, Shahad; Almutairi, Mansour S; Alghamdi, Badr; Alomran, Nawaf; Sheereen, Atia; Daghestani, Maha; Massadeh, Salam

2018-01-01

Anastrozole (ANS) is an aromatase inhibitor that is widely used as a treatment for breast cancer in postmenopausal women. Despite the wide use of ANS, it is associated with serious side effects due to uncontrolled delivery. In addition, ANS exhibits low solubility and short plasma half-life. Nanotechnology-based drug delivery has the potential to enhance the efficacy of drugs and overcome undesirable side effects. In this study, we aimed to prepare novel ANS-loaded PLA-PEG-PLA nanoparticles (ANS-NPs) and to compare the apoptotic response of MCF-7 cell line to both ANS and ANS-loaded NPs. ANS-NPs were synthesized using double emulsion method and characterized using different methods. The apoptotic response was evaluated by assessing cell viability, morphology, and studying changes in the expression of MAPK3 , MCL1 , and c-MYC apoptotic genes in MCF-7 cell lines. ANS was successfully encapsulated within PLA-PEG-PLA, forming monodisperse therapeutic NPs with an encapsulation efficiency of 67%, particle size of 186±27.13, and a polydispersity index of 0.26±0.11 with a sustained release profile extended over 144 hours. In addition, results for cell viability and for gene expression represent a similar apoptotic response between the free ANS and ANS-NPs. The synthesized ANS-NPs showed a similar therapeutic effect as the free ANS, which provides a rationale to pursue pre-clinical evaluation of ANS-NPs on animal models.

Oxidized low-density lipoprotein-induced apoptotic dendritic cells as a novel therapy for atherosclerosis

NARCIS (Netherlands)

Frodermann, Vanessa; van Puijvelde, Gijs H M; Wierts, Laura; Lagraauw, H Maxime; Foks, Amanda C; van Santbrink, Peter J; Bot, Ilze; Kuiper, Johan; de Jager, Saskia C A

2015-01-01

Modulation of immune responses may form a powerful approach to treat atherosclerosis. It was shown that clearance of apoptotic cells results in tolerance induction to cleared Ags by dendritic cells (DCs); however, this seems impaired in atherosclerosis because Ag-specific tolerance is lacking. This

Bee venom protects SH-SY5Y human neuroblastoma cells from 1-methyl-4-phenylpyridinium-induced apoptotic cell death.

Science.gov (United States)

Doo, Ah-Reum; Kim, Seung-Nam; Kim, Seung-Tae; Park, Ji-Yeun; Chung, Sung-Hyun; Choe, Bo-Young; Chae, Younbyoung; Lee, Hyejung; Yin, Chang-Shik; Park, Hi-Joon

2012-01-06

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by progressive selective loss of dopaminergic neurons in the substantia nigra. Recently, bee venom was reported to protect dopaminergic neurons in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine induced mice PD model, however, the underlying mechanism is not fully understood. The objective of the present study is to investigate the neuroprotective mechanism of bee venom against Parkinsonian toxin, 1-methyl-4-phenylpyridine (MPP(+)), in SH-SY5Y human neuroblastoma cells. Our results revealed that bee venom pretreatment (1-100 ng/ml) increased the cell viability and decreased apoptosis assessed by DNA fragmentation and caspase-3 activity assays in MPP(+)-induced cytotoxicity in SH-SY5Y cells. Bee venom increased the anti-apoptotic Bcl-2 expression and decreased the pro-apoptotic Bax, cleaved PARP expressions. In addition, bee venom prevented the MPP(+)-induced suppression of Akt phosphorylation, and the neuroprotective effect of bee venom against MPP(+)-induced cytotoxicity was inhibited by a phosphatidylinositol 3-kinase (PI3K) inhibitor, LY294002. These results suggest that the anti-apoptotic effect of bee venom is mediated by the cell survival signaling, the PI3K/Akt pathway. These results provide new evidence for elucidating the mechanism of neuroprotection of bee venom against PD. Copyright © 2011 Elsevier B.V. All rights reserved.

ANTIPROLIFERATIVE AND APOPTOTIC EFFECTS OF THE ESSENTIAL OIL OF ORIGANUM ONITES AND CARVACROL ON HEP-G2 CELLS

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Özlem TOMSUK

2011-08-01

Full Text Available The essential oil Origanum onites L. and its phenolic constituent carvacrol were examined for their cytotoxic and apoptotic effects in a human hepatocellular carcinoma cells Hep-G2. WST-1 and neutral red uptake assays were performed to determine the inhibitory effects of the oil and carvacrol on the growth of the cells. Possible induction of apoptosis by Origanum oil and carvacrol was further investigated by acridine orange/ethidium bromide (AO/EB staining. Results showed that the Ori- ganum oil and carvacrol was significantly cytotoxic and induced apoptosis in Hep-G2 cells. IC₅₀ value of essential oil and carvacrol was found about 0,009% (v/v and 500 μM, respectively. After incuba- tion of the cells with Origanum oil and carvacrol, characteristics of apoptotic morphology such as chromatin condensation, shrinkage of the cells and cytoplasmic blebbing was observed. In conclusion, both essential oil and its major constituent carvacrol significantly exhibited cytotoxic and apoptotic activities in hepatocellular carcinoma cells, indicating its potential for use as an anticancer agent.

ARP2, a novel pro-apoptotic protein expressed in epithelial prostate cancer LNCaP cells and epithelial ovary CHO transformed cells.

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Mas-Oliva, Jaime; Navarro-Vidal, Enrique; Tapia-Vieyra, Juana Virginia

2014-01-01

Neoplastic epithelial cells generate the most aggressive types of cancers such as those located in the lung, breast, colon, prostate and ovary. During advanced stages of prostate cancer, epithelial cells are associated to the appearance of androgen-independent tumors, an apoptotic-resistant phenotype that ultimately overgrows and promotes metastatic events. We have previously identified and electrophysiologically characterized a novel Ca(2+)-permeable channel activated during apoptosis in the androgen-independent prostate epithelial cancer cell line, LNCaP. In addition, we reported for the first time the cloning and characterization of this channel-like molecule named apoptosis regulated protein 2 (ARP2) associated to a lethal influx of Ca(2+) in Xenopus oocytes. In the present study, LNCaP cells and Chinese hamster ovary cells (CHO cell line) transfected with arp2-cDNA are induced to undergo apoptosis showing an important impact on cell viability and activation of caspases 3 and 7 when compared to serum deprived grown cells and ionomycin treated cells. The subcellular localization of ARP2 in CHO cells undergoing apoptosis was studied using confocal microscopy. While apoptosis progresses, ARP2 initially localized in the peri-nuclear region of cells migrates with time towards the plasma membrane region. Based on the present results and those of our previous studies, the fact that ARP2 constitutes a novel cation channel is supported. Therefore, ARP2 becomes a valuable target to modulate the influx and concentration of calcium in the cytoplasm of epithelial cancer cells showing an apoptotic-resistant phenotype during the onset of an apoptotic event.

Externalization and recognition by macrophages of large subunit of eukaryotic translation initiation factor 3 in apoptotic cells

International Nuclear Information System (INIS)

Nakai, Yuji; Shiratsuchi, Akiko; Manaka, Junko; Nakayama, Hiroshi; Takio, Koji; Zhang Jianting; Suganuma, Tatsuo; Nakanishi, Yoshinobu

2005-01-01

We previously isolated a monoclonal antibody named PH2 that inhibits phosphatidylserine-mediated phagocytosis of apoptotic cells by macrophages [C. Fujii, A. Shiratsuchi, J. Manaka, S. Yonehara, Y. Nakanishi. Cell Death Differ. 8 (2001) 1113-1122]. We report here the identification of the cognate antigen. A protein bound by PH2 in Western blotting was identified as the 170-kDa subunit of eukaryotic translation initiation factor 3 (eIF3 p170/eIF3a). When eIF3a was expressed in a culture cell line as a protein fused to green fluorescence protein, the fusion protein was detected at the cell surface only after the induction of apoptosis. The same phenomenon was seen when the localization of endogenous eIF3a was determined using anti-eIF3a antibody, and eIF3a seemed to be partially degraded during apoptosis. Furthermore, bacterially expressed N-terminal half of eIF3a fused to glutathione S-transferase bound to the surface of macrophages and inhibited phagocytosis of apoptotic cells by macrophages when it was added to phagocytosis reactions. These results collectively suggest that eIF3a translocates to the cell surface upon apoptosis, probably after partial degradation, and bridges apoptotic cells and macrophages to enhance phagocytosis

Involvement of DNA-PK and ATM in radiation- and heat-induced DNA damage recognition and apoptotic cell death

International Nuclear Information System (INIS)

Tomita, Masanori

2010-01-01

Exposure to ionizing radiation and hyperthermia results in important biological consequences, e.g. cell death, chromosomal aberrations, mutations, and DNA strand breaks. There is good evidence that the nucleus, specifically cellular DNA, is the principal target for radiation-induced cell lethality. DNA double-strand breaks (DSBs) are considered to be the most serious type of DNA damage induced by ionizing radiation. On the other hand, verifiable mechanisms which can lead to heat-induced cell death are damage to the plasma membrane and/or inactivation of heat-labile proteins caused by protein denaturation and subsequent aggregation. Recently, several reports have suggested that DSBs can be induced after hyperthermia because heat-induced phosphorylated histone H2AX (γ-H2AX) foci formation can be observed in several mammalian cell lines. In mammalian cells, DSBs are repaired primarily through two distinct and complementary mechanisms: non-homologous end joining (NHEJ), and homologous recombination (HR) or homology-directed repair (HDR). DNA-dependent protein kinase (DNA-PK) and ataxia-telangiectasia mutated (ATM) are key players in the initiation of DSB repair and phosphorylate and/or activate many substrates, including themselves. These phosphorylated substrates have important roles in the functioning of cell cycle checkpoints and in cell death, as well as in DSB repair. Apoptotic cell death is a crucial cell suicide mechanism during development and in the defense of homeostasis. If DSBs are unrepaired or misrepaired, apoptosis is a very important system which can protect an organism against carcinogenesis. This paper reviews recently obtained results and current topics concerning the role of DNA-PK and ATM in heat- or radiation-induced apoptotic cell death. (author)

Host cell killing by the West Nile Virus NS2B-NS3 proteolytic complex: NS3 alone is sufficient to recruit caspase-8-based apoptotic pathway

International Nuclear Information System (INIS)

Ramanathan, Mathura P.; Chambers, Jerome A.; Pankhong, Panyupa; Chattergoon, Michael; Attatippaholkun, Watcharee; Dang, Kesen; Shah, Neelima; Weiner, David B.

2006-01-01

The West Nile Virus (WNV) non-structural proteins 2B and 3 (NS2B-NS3) constitute the proteolytic complex that mediates the cleavage and processing of the viral polyprotein. NS3 recruits NS2B and NS5 proteins to direct protease and replication activities. In an effort to investigate the biology of the viral protease, we cloned cDNA encoding the NS2B-NS3 proteolytic complex from brain tissue of a WNV-infected dead crow, collected from the Lower Merion area (Merion strain). Expression of the NS2B-NS3 gene cassette induced apoptosis within 48 h of transfection. Electron microscopic analysis of NS2B-NS3-transfected cells revealed ultra-structural changes that are typical of apoptotic cells including membrane blebbing, nuclear disintegration and cytoplasmic vacuolations. The role of NS3 or NS2B in contributing to host cell apoptosis was examined. NS3 alone triggers the apoptotic pathways involving caspases-8 and -3. Experimental results from the use of caspase-specific inhibitors and caspase-8 siRNA demonstrated that the activation of caspase-8 was essential to initiate apoptotic signaling in NS3-expressing cells. Downstream of caspase-3 activation, we observed nuclear membrane ruptures and cleavage of the DNA-repair enzyme, PARP in NS3-expressing cells. Nuclear herniations due to NS3 expression were absent in the cells treated with a caspase-3 inhibitor. Expression of protease and helicase domains themselves was sufficient to trigger apoptosis generating insight into the apoptotic pathways triggered by NS3 from WNV

Apoptotic effect of a novel kefir product, PFT, on multidrug-resistant myeloid leukemia cells via a hole-piercing mechanism

Science.gov (United States)

GHONEUM, MAMDOOH; GIMZEWSKI, JAMES

2014-01-01

We examined the apoptotic effect of a novel Probiotics Fermentation Technology (PFT) kefir grain product; PFT is a natural mixture composed primarily of Lactobacillus kefiri P-IF, a specific strain of L. kefiri with unique growth characteristics. The aim of this study was to examine the apoptotic effect of PFT on human multidrug-resistant (MDR) myeloid leukemia (HL60/AR) cells in vitro and explore the mechanistic approach underlying its effect. HL60/AR cells were cultured with PFT (0.6–5.0 mg/ml) for 3 days. The apoptotic effect of PFT was assessed through examination of percent apoptosis, caspase 3 activation, Bcl-2 expression levels and changes in mitochondrial membrane potential (MMP). PFT induced apoptosis in HL60/AR cells in a dose-dependent manner which was maximal at 67.5% for 5 mg/ml. Induction of apoptosis was associated with activation of caspase 3, decreased expression of Bcl-2 and decreased polarization of MMP. In addition, PFT showed a unique characteristic of piercing holes in HL60/AR cells, as indicated by AFM studies. This hole induction may be responsible for the apoptotic effect on cancer cells. These results suggest that PFT may act as a potential therapy for the treatment of MDR leukemia. PMID:24430613

Cordycepin enhances cisplatin apoptotic effect through caspase/MAPK pathways in human head and neck tumor cells

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Chen YH

2013-07-01

Full Text Available Ying-Hui Chen,1,2,* Jo-Yu Wang,3,* Bo-Syong Pan,3,4 Yi-Fen Mu,3 Meng-Shao Lai,3,4 Edmund Cheung So,5 Thian-Sze Wong,6 Bu-Miin Huang3,4 1Department of Anesthesia, Chi-Mei Medical Center, Liouying, 2Department of Nursing, Min-Hwei College of Health Care Management, 3Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, 4The Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, 5Department of Anesthesia, An Nan Hospital, China Medical University, Tainan, Taiwan; 6Department of Surgery, University of Hong Kong Medical Center, Faculty of Medicine, The University of Hong Kong, Hong Kong *Authors contributed equally to this work Purpose: The present study aims to investigate whether the combination treatment of cordycepin (an extracted pure compound from Cordyceps sinensis and cisplatin (a platinum-based chemotherapy drug has better apoptotic effect in head and neck squamous cell carcinoma (HNSCC. Methods: The apoptotic influences of cordycepin and/or cisplatin treatments to human OC3, OEC-M1, and FaDu HNSCC cells were investigated by morphological observations, viability assay, flow cytometry assay, and Western blotting methods. Results: Data showed that the cell death phenomenon increased as the dosage of cordycepin or cisplatin increased, and it appeared more in cordycepin plus cisplatin cotreatment among three cell lines. Cell survival rates significantly decreased as the dosage of cordycepin or cisplatin increased, and the better apoptotic effects were observed in cotreatment. Cell cycle analysis further demonstrated that percentages of subG1 cells in cordycepin or cisplatin treatments significantly increased, suggesting that cells underwent apoptosis, and cordycepin plus cisplatin induced many more subG1 cells. Furthermore, cordycepin or cisplatin induced caspase-8, caspase-9, caspase-3, and poly adenosine diphosphate-ribose polymerase protein cleavages, and stimulated c

Involvement of caspase-12-dependent apoptotic pathway in ionic radiocontrast urografin-induced renal tubular cell injury

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Wu, Cheng Tien [Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Weng, Te I. [Department of Forensic Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Chen, Li Ping [Department of Dentistry, Chang Gang Memorial Hospital, Chang Gang University, Taoyuan, Taiwan (China); Chiang, Chih Kang [Department of Integrated Diagnostics and Therapeutics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China); Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan (China); Liu, Shing Hwa, E-mail: shinghwaliu@ntu.edu.tw [Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Department of Urology, National Taiwan University Hospital, Taipei, Taiwan (China)

2013-01-01

Contrast medium (CM) induces a direct toxic effect on renal tubular cells. This toxic effect subjects in the disorder of CM-induced nephropathy. Our previous work has demonstrated that CM shows to activate the endoplasmic reticulum (ER)-related adaptive unfolding protein response (UPR) activators. Glucose-regulated protein 78 (GRP78)/eukaryotic initiation factor 2α (eIF2α)-related pathways play a protective role during the urografin (an ionic CM)-induced renal tubular injury. However, the involvement of ER stress-related apoptotic signals in the urografin-induced renal tubular cell injury remains unclear. Here, we examined by the in vivo and in vitro experiments to explore whether ER stress-regulated pro-apoptotic activators participate in urografin-induced renal injury. Urografin induced renal tubular dilation, tubular cells detachment, and necrosis in the kidneys of rats. The tubular apoptosis, ER stress-related pro-apoptotic transcriptional factors, and kidney injury marker-1 (kim-1) were also conspicuously up-regulated in urografin-treated rats. Furthermore, treatment of normal rat kidney (NRK)-52E tubular cells with urografin augmented the expressions of activating transcription factor-6 (ATF-6), C/EBP homologous protein (CHOP), Bax, caspase-12, JNK, and inositol-requiring enzyme (IRE) 1 signals. Urografin-induced renal tubular cell apoptosis was not reversed by the inhibitors of ATF-6, JNK signals or CHOP siRNA transfection, but it could be partially reversed by the inhibitor of caspase-12. Taken together, the present results and our previous findings suggest that exposure of CM/urografin activates the ER stress-regulated survival- and apoptosis-related signaling pathways in renal tubular cells. Caspase-12-dependent apoptotic pathway may be partially involved in the urografin-induced nephropathy. -- Highlights: ► Ionic contrast medium-urografin induces renal tubular cell apoptosis. ► Urografin induces the ER stress-regulated survival and apoptosis

Molecular interactions of prodiginines with the BH3 domain of anti-apoptotic Bcl-2 family members.

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Ali Hosseini

Full Text Available Prodigiosin and obatoclax, members of the prodiginines family, are small molecules with anti-cancer properties that are currently under preclinical and clinical trials. The molecular target(s of these agents, however, is an open question. Combining experimental and computational techniques we find that prodigiosin binds to the BH3 domain in some BCL-2 protein families, which play an important role in the apoptotic programmed cell death. In particular, our results indicate a large affinity of prodigiosin for MCL-1, an anti-apoptotic member of the BCL-2 family. In melanoma cells, we demonstrate that prodigiosin activates the mitochondrial apoptotic pathway by disrupting MCL-1/BAK complexes. Computer simulations with the PELE software allow the description of the induced fit process, obtaining a detailed atomic view of the molecular interactions. These results provide new data to understand the mechanism of action of these molecules, and assist in the development of more specific inhibitors of anti-apoptotic BCL-2 proteins.

Synergistic apoptotic response between valproic acid and fludarabine in chronic lymphocytic leukaemia (CLL) cells involves the lysosomal protease cathepsin B

International Nuclear Information System (INIS)

Yoon, J-Y; Szwajcer, D; Ishdorj, G; Benjaminson, P; Xiao, W; Kumar, R; Johnston, J B; Gibson, S B

2013-01-01

Fludarabine, a nucleoside analogue, is commonly used in combination with other agents for the treatment of chronic lymphocytic leukaemia (CLL). In previous studies, valproic acid (VPA), an inhibitor of histone deacetylases, combined with fludarabine to synergistically increase apoptotic cell death in CLL cells. In the present study, we found that the combination of fludarabine and VPA decreases the level of the anti-apoptotic proteins Mcl-1 and XIAP in primary CLL cells. Treatment with fludarabine alone, or in combination with VPA, led to the loss of lysosome integrity, and chemical inhibition of the lysosomal protease cathepsin B, using CA074-Me, was sufficient to reduce apoptosis. VPA treatment increased cathepsin B levels and activities in primary CLL cells, thereby priming CLL cells for lysosome-mediated cell death. Six previously treated patients with relapsed CLL were treated with VPA, followed by VPA/fludarabine combination. The combined therapy resulted in reduced lymphocyte count in five out of six and reduced lymph node sizes in four out of six patients. In vivo VPA treatment increased histone-3 acetylation and cathepsin B expression levels. Thus, the synergistic apoptotic response with VPA and fludarabine in CLL is mediated by cathepsin B activation leading to a decrease in the anti-apoptotic proteins

Phagocytosis (cannibalism) of apoptotic neutrophils by tumor cells in gastric micropapillary carcinomas.

Science.gov (United States)

Barresi, Valeria; Branca, Giovanni; Ieni, Antonio; Rigoli, Luciana; Tuccari, Giovanni; Caruso, Rosario Alberto

2015-05-14

To identify those with a micropapillary pattern, ascertain relative frequency and document clinicopathological characteristics by reviewing gastric carcinomas. One hundred and fifty-one patients diagnosed with gastric cancer who underwent gastrectomy were retrospectively studied and the presence of a regional invasive micropapillary component was evaluated by light microscopy. All available hematoxylin-eosin (HE)-stained slides were histologically reviewed and 5 tumors were selected as putative micropapillary carcinoma when cancer cell clusters without a vascular core within empty lymphatic-like space comprised at least 5% of the tumor. Tumor tissues from these 5 invasive gastric carcinomas were immunostained using an anti-mucin 1 (MUC1) antibody (clone MA695) to detect the characteristic inside-out pattern and with D2-40 antibody to determine the presence of intratumoral lymph vessels. Detection of intraepithelial neutrophil apoptosis was evaluated in consecutive histological tissue sections by three independent methods, namely light microscopy with HE staining, the conventional terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method and immunohistochemistry for activated caspase-3 (clone C92-605). Among 151 gastric cancers resected for cure, 5 (3.3%) were adenocarcinomas with a micropapillary component. Four of the patients died of disease from 6 to 23 mo and one patient was alive with metastases at 9 mo. All patients had advanced-stage cancer (≥ pT2) and lymph node metastasis. Positive MUC1 immunostaining on the stroma-facing surface (inside-out pattern) of the carcinomatous cluster cells, together with negative immunostaining for D2-40 in the cells limiting lymphatic-like spaces, confirmed the true micropapillary pattern in these gastric neoplasms. In all five cases, several micropapillae were infiltrated by neutrophils. HE staining, TUNEL assay and immunostaining for caspase-3 demonstrated apoptotic neutrophils within

Molecular analysis of the apoptotic effects of BPA in acute myeloid leukemia cells

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Del Pozzo Giovanna

2009-06-01

Full Text Available Abstract Background: BPA (bisphenol A or 2,2-bis(4-hydroxy-phenolpropane is present in the manufacture of polycarbonate plastic and epoxy resins, which can be used in impact-resistant safety equipment and baby bottles, as protective coatings inside metal food containers, and as composites and sealants in dentistry. Recently, attention has focused on the estrogen-like and carcinogenic adverse effects of BPA. Thus, it is necessary to investigate the cytotoxicity and apoptosis-inducing activity of this compound. Methods: Cell cycle, apoptosis and differentiation analyses; western blots. Results: BPA is able to induce cell cycle arrest and apoptosis in three different acute myeloid leukemias. Although some granulocytic differentiation concomitantly occurred in NB4 cells upon BPA treatment, the major action was the induction of apoptosis. BPA mediated apoptosis was caspase dependent and occurred by activation of extrinsic and intrinsic cell death pathways modulating both FAS and TRAIL and by inducing BAD phosphorylation in NB4 cells. Finally, also non genomic actions such as the early decrease of both ERK and AKT phosphorylation were induced by BPA thus indicating that a complex intersection of regulations occur for the apoptotic action of BPA. Conclusion: BPA is able to induce apoptosis in leukemia cells via caspase activation and involvement of both intrinsic and extrinsic pathways of apoptosis.

Silver nanoparticles of different sizes induce a mixed type of programmed cell death in human pancreatic ductal adenocarcinoma

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Zielinska, Ewelina; Zauszkiewicz-Pawlak, Agata; Wojcik, Michal; Inkielewicz-Stepniak, Iwona

2018-01-01

Pancreatic ductal adenocarcinoma, with the high resistance to chemotherapeutic agents, remains the fourth leading cause of cancer-death in the world. Due to the wide range of biological activity and unique properties, silver nanoparticles (AgNPs) are indicated as agents with potential to overcome barriers involved in chemotherapy failure. Therefore, in our study we decided to assess the ability of AgNPs to kill pancreatic cancer cells, and then to identify the molecular mechanism underlying this effect. Moreover, we evaluated the cytotoxicity of AgNPs against non-tumor cell of the same tissue (hTERT-HPNE cells) for comparison. Our results indicated that AgNPs with size of 2.6 and 18 nm decreased viability, proliferation and caused death of pancreatic cancer cells in a size- and concentration-dependent manner. Ultrastructural analysis identified that cellular uptake of AgNPs resulted in apoptosis, autophagy, necroptosis and mitotic catastrophe. These alterations were associated with increased pro-apoptotic protein Bax and decreased level of anti-apoptotic protein Bcl-2. Moreover, AgNPs significantly elevated the level of tumor suppressor p53 protein as well as necroptosis- and autophagy-related proteins: RIP-1, RIP-3, MLKL and LC3-II, respectively. In addition, we found that PANC-1 cells were more vulnerable to AgNPs-induced cytotoxicity compared to pancreatic non-tumor cells. In conclusion, AgNPs by inducing mixed type of programmed cell death in PANC-1 cells, could provide a new therapeutic strategy to overcome chemoresistance in one of the deadliest human cancer. PMID:29435134

Caloric restriction suppresses apoptotic cell death in the mammalian cochlea and leads to prevention of presbycusis.

Science.gov (United States)

Someya, Shinichi; Yamasoba, Tatsuya; Weindruch, Richard; Prolla, Tomas A; Tanokura, Masaru

2007-10-01

Presbycusis is characterized by an age-related progressive decline of auditory function, and arises mainly from the degeneration of hair cells or spiral ganglion (SG) cells in the cochlea. Here we show that caloric restriction suppresses apoptotic cell death in the mouse cochlea and prevents late onset of presbycusis. Calorie restricted (CR) mice, which maintained body weight at the same level as that of young control (YC) mice, retained normal hearing and showed no cochlear degeneration. CR mice also showed a significant reduction in the number of TUNEL-positive cells and cleaved caspase-3-positive cells relative to middle-age control (MC) mice. Microarray analysis revealed that CR down-regulated the expression of 24 apoptotic genes, including Bak and Bim. Taken together, our findings suggest that loss of critical cells through apoptosis is an important mechanism of presbycusis in mammals, and that CR can retard this process by suppressing apoptosis in the inner ear tissue.

Title of paper: the induction of P-53 independent programmed cell death (apoptosis) with ionizing radiation and 5-fluorouracil (5-FU) in the HT-29 human colon carcinoma cell line

International Nuclear Information System (INIS)

Blackstock, A. Wm.; Gill, Misha; Hess, Suzanne M.; Fisher, Robert W.; Leadon, Steven A.; Tepper, Joel E.

1996-01-01

Purpose/Objective: The role of programmed cell death (apoptosis) as a cellular response to cancer therapy such as radiation or chemotherapy is the subject of much study, and manipulation of the apoptotic response in tumor cells may be valuable in the treatment of a variety of cancers. Both p53 dependent and independent apoptotic pathways have been identified; p53 is mutated in at least 50 % of human cancers and a majority of radiation resistant tumors contain p53 mutations. This study is designed to examine the induction of programmed cell death in a human colon carcinoma cell line that possesses two mutated p53 alleles. Ionizing radiation alone, or in combination with the chemotherapeutic drug 5-fluorouracil (5-FU), were used to elicit the apoptotic response. This study will focus on whether these treatments can induce a significant apoptotic response in cells that have mutated p53 alleles. Materials and Methods: HT-29 cells were assessed for clonogenic survival after being plated at a variety of densities, and treated with single graded doses of radiation (0, 1, 2, 4, 6, 8, 10 Gy) either alone or immediately prior to a 24 hour exposure to 5-FU (2 ug/ml). The extent of radiation and 5-FU-induced apoptosis was determined in the HT-29 cell line after single doses of 0, 2, 5, and 10 Gy either alone or immediately prior to a 24 hour incubation in 5-FU (2 ug/ml). Three separate assays were used to evaluate the apoptotic response. Cells undergoing apoptosis undergo gross morphological changes including a condensation of chromatin, membrane blebbing, and an eventual release of membrane bound cytoplasmic fragments. Hematoxylin and eosin staining were used to visualize some of these morphological changes. Another characteristic of the apoptotic response is the activation of an endonuclease that cleaves DNA into specific fragments. Accordingly, an ELISA cell death assay (Boehringer Mannheim, Indianapolis IN) was used to quantitate cytoplasmic histone-associated DNA

Aged garlic extract and S-allylcysteine prevent apoptotic cell death in a chemical hypoxia model

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Marisol Orozco-Ibarra

Full Text Available BACKGROUND: Aged garlic extract (AGE and its main constituent S-allylcysteine (SAC are natural antioxidants with protective effects against cerebral ischemia or cancer, events that involve hypoxia stress. Cobalt chloride (CoCl2 has been used to mimic hypoxic conditions through the stabilization of the α subunit of hypoxia inducible factor (HIF-Ια and up-regulation of HIF-1a-dependent genes as well as activation of hypoxic conditions such as reactive oxygen species (ROS generation, loss of mitochondrial membrane potential and apoptosis. The present study was designed to assess the effect of AGE and SAC on the CoCl2-chemical hypoxia model in PC12 cells RESULTS: We found that CoCl2 induced the stabilization of HIF-1a and its nuclear localization. CoCl2 produced ROS and apoptotic cell death that depended on hypoxia extent. The treatment with AGE and SAC decreased ROS and protected against CoCl2-induced apoptotic cell death which depended on the CoCl2 concentration and incubation time. SAC or AGE decreased the number of cells in the early and late stages of apoptosis. Interestingly, this protective effect was associated with attenuation in HIF-1a stabilization, activity not previously reported for AGE and SAC CONCLUSIONS: Obtained results show that AGE and SAC decreased apoptotic CoCl2-induced cell death. This protection occurs by affecting the activity of HIF-1a and supports the use of these natural compounds as a therapeutic alternative for hypoxic conditions

Agmatine Attenuates Brain Edema and Apoptotic Cell Death after Traumatic Brain Injury.

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Kim, Jae Young; Lee, Yong Woo; Kim, Jae Hwan; Lee, Won Taek; Park, Kyung Ah; Lee, Jong Eun

2015-07-01

Traumatic brain injury (TBI) is associated with poor neurological outcome, including necrosis and brain edema. In this study, we investigated whether agmatine treatment reduces edema and apoptotic cell death after TBI. TBI was produced by cold injury to the cerebral primary motor cortex of rats. Agmatine was administered 30 min after injury and once daily until the end of the experiment. Animals were sacrificed for analysis at 1, 2, or 7 days after the injury. Various neurological analyses were performed to investigate disruption of the blood-brain barrier (BBB) and neurological dysfunction after TBI. To examine the extent of brain edema after TBI, the expression of aquaporins (AQPs), phosphorylation of mitogen-activated protein kinases (MAPKs), and nuclear translocation of nuclear factor-κB (NF-κB) were investigated. Our findings demonstrated that agmatine treatment significantly reduces brain edema after TBI by suppressing the expression of AQP1, 4, and 9. In addition, agmatine treatment significantly reduced apoptotic cell death by suppressing the phosphorylation of MAPKs and by increasing the nuclear translocation of NF-κB after TBI. These results suggest that agmatine treatment may have therapeutic potential for brain edema and neural cell death in various central nervous system diseases.

Nickel oxide nanoparticles exert cytotoxicity via oxidative stress and induce apoptotic response in human liver cells (HepG2).

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Ahamed, Maqusood; Ali, Daoud; Alhadlaq, Hisham A; Akhtar, Mohd Javed

2013-11-01

Increasing use of nickel oxide nanoparticles (NiO NPs) necessitates an improved understanding of their potential impact on human health. Previously, toxic effects of NiO NPs have been investigated, mainly on airway cells. However, information on effect of NiO NPs on human liver cells is largely lacking. In this study, we investigated the reactive oxygen species (ROS) mediated cytotoxicity and induction of apoptotic response in human liver cells (HepG2) due to NiO NPs exposure. Prepared NiO NPs were crystalline and spherical shaped with an average diameter of 44 nm. NiO NPs induced cytotoxicity (cell death) and ROS generation in HepG2 cells in dose-dependent manner. Further, ROS scavenger vitamin C reduced cell death drastically caused by NiO NPs exposure indicating that oxidative stress plays an important role in NiO NPs toxicity. Micronuclei induction, chromatin condensation and DNA damage in HepG2 cells treated with NiO NPs suggest that NiO NPs induced cell death via apoptotic pathway. Quantitative real-time PCR analysis showed that following the exposure of HepG2 cells to NiO NPs, the expression level of mRNA of apoptotic genes (bax and caspase-3) were up-regulated whereas the expression level of anti-apoptotic gene bcl-2 was down-regulated. Moreover, activity of caspase-3 enzyme was also higher in NiO NPs treated cells. To the best of our knowledge this is the first report demonstrating that NiO NPs caused cytotoxicity via ROS and induced apoptosis in HepG2 cells, which is likely to be mediated through bax/bcl-2 pathway. This work warrants careful assessment of Ni NPs before their commercial and industrial applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

ANTITUMOR AND APOPTOTIC EFFECTS OF CUCURBITACIN A IN A-549 LUNG CARCINOMA CELLS IS MEDIATED VIA G2/M CELL CYCLE ARREST AND M-TOR/PI3K/AKT SIGNALLING PATHWAY.

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Wang, Wen-Dong; Liu, Yan; Su, Yuan; Xiong, Xian-Zhi; Shang, Dan; Xu, Juan-Juan; Liu, Hong-Ju

2017-01-01

The main aim of this study was to demonstrate the antitumor potential of cucurbitacin A on A-549 NSCLC (non-small cell lung cancer cells). The effects of Cucurbitacin A on apoptotic induction, cell physic, cell cycle failure and m-TOR/PI3K/Akt signalling pathway were also investigated in the present study. MTT assay and clonogenic assay were carried out to study effects of this compound on cell cytotoxicity and colony forming tendency in A-549 cells. Moreover, phase and fluorescence microscopic techniques were used to examine the effects on cell morphology and induction of apoptosis. The effects on cell cycle phase distribution were investigated by flow cytometry and effects on m-TOR/PI3K/Akt signalling proteins were assessed by western blot analysis. Results showed that cucurbitacin A induced dose-dependent cytotoxic effects along with suppressing the colony forming tendency in these cells. Cucurbitacin A also induced morphological changes in these cells featuring chromatin condensation, cell shrinkage and apoptotic body formation. G2/M phase cell cycle collapse was also induced by Cucurbitacin A along with inhibition of expression levels of m-TOR/PI3K/Akt proteins. In conclusion, cucurbitacin A inhibits cancer growth in A-549 NSCLC cells by inducing apoptosis, targeting m-TOR/PI3K/Akt signalling pathway and G2/M cell cycle.

Apoptotic DNA Degradation into Oligonucleosomal Fragments, but Not Apoptotic Nuclear Morphology, Relies on a Cytosolic Pool of DFF40/CAD Endonuclease*

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Iglesias-Guimarais, Victoria; Gil-Guiñon, Estel; Gabernet, Gisela; García-Belinchón, Mercè; Sánchez-Osuna, María; Casanelles, Elisenda; Comella, Joan X.; Yuste, Victor J.

2012-01-01

Apoptotic cell death is characterized by nuclear fragmentation and oligonucleosomal DNA degradation, mediated by the caspase-dependent specific activation of DFF40/CAD endonuclease. Here, we describe how, upon apoptotic stimuli, SK-N-AS human neuroblastoma-derived cells show apoptotic nuclear morphology without displaying concomitant internucleosomal DNA fragmentation. Cytotoxicity afforded after staurosporine treatment is comparable with that obtained in SH-SY5Y cells, which exhibit a complete apoptotic phenotype. SK-N-AS cell death is a caspase-dependent process that can be impaired by the pan-caspase inhibitor q-VD-OPh. The endogenous inhibitor of DFF40/CAD, ICAD, is correctly processed, and dff40/cad cDNA sequence does not reveal mutations altering its amino acid composition. Biochemical approaches show that both SH-SY5Y and SK-N-AS resting cells express comparable levels of DFF40/CAD. However, the endonuclease is poorly expressed in the cytosolic fraction of healthy SK-N-AS cells. Despite this differential subcellular distribution of DFF40/CAD, we find no differences in the subcellular localization of both pro-caspase-3 and ICAD between the analyzed cell lines. After staurosporine treatment, the preferential processing of ICAD in the cytosolic fraction allows the translocation of DFF40/CAD from this fraction to a chromatin-enriched one. Therefore, the low levels of cytosolic DFF40/CAD detected in SK-N-AS cells determine the absence of DNA laddering after staurosporine treatment. In these cells DFF40/CAD cytosolic levels can be restored by the overexpression of their own endonuclease, which is sufficient to make them proficient at degrading their chromatin into oligonucleosome-size fragments after staurosporine treatment. Altogether, the cytosolic levels of DFF40/CAD are determinants in achieving a complete apoptotic phenotype, including oligonucleosomal DNA degradation. PMID:22253444

Loss of functional E-cadherin renders cells more resistant to the apoptotic agent taxol in vitro

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Ferreira, Paulo; Oliveira, Maria Jose; Beraldi, Eliana; Mateus, Ana Rita; Nakajima, Takashi; Gleave, Martin; Yokota, Jun; Carneiro, Fatima; Huntsman, David; Seruca, Raquel; Suriano, Gianpaolo

2005-01-01

Experimental evidence supports a role for E-cadherin in suppressing invasion, metastasis, and proliferation. Germline mutations of the E-cadherin represent the genetic cause of hereditary diffuse gastric cancer (HDGC). In this type of tumor, isolated cancer cells permeate the basal membrane and paradoxically survive in the gastric wall in the absence of contact with neighbor epithelial cells or with the extracellular matrix. This suggests that upon E-cadherin deregulation, cells acquired resistance to apoptosis. To test this hypothesis, CHO cells stably expressing either wild-type E-cadherin or the HDGC-related germline mutations T340A and V832M were seeded either on a thin layer of collagen type I or on plastic and then subjected to the apoptotic agent taxol. We found that in vitro functional E-cadherin renders cells more sensitive to the effect of taxol. Our results also indicate that this effect is associated to decreased level of the anti-apoptotic bcl-2 protein

Bifidobacterium breve reduces apoptotic epithelial cell shedding in an exopolysaccharide and MyD88-dependent manner.

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Hughes, K R; Harnisch, L C; Alcon-Giner, C; Mitra, S; Wright, C J; Ketskemety, J; van Sinderen, D; Watson, A J M; Hall, L J

2017-01-01

Certain members of the microbiota genus Bifidobacterium are known to positively influence host well-being. Importantly, reduced bifidobacterial levels are associated with inflammatory bowel disease (IBD) patients, who also have impaired epithelial barrier function, including elevated rates of apoptotic extrusion of small intestinal epithelial cells (IECs) from villi-a process termed 'cell shedding'. Using a mouse model of pathological cell shedding, we show that mice receiving Bifidobacterium breve UCC2003 exhibit significantly reduced rates of small IEC shedding. Bifidobacterial-induced protection appears to be mediated by a specific bifidobacterial surface exopolysaccharide and interactions with host MyD88 resulting in downregulation of intrinsic and extrinsic apoptotic responses to protect epithelial cells under highly inflammatory conditions. Our results reveal an important and previously undescribed role for B. breve, in positively modulating epithelial cell shedding outcomes via bacterial- and host-dependent factors, supporting the notion that manipulation of the microbiota affects intestinal disease outcomes. © 2017 The Authors.

Kaurene diterpene induces apoptosis in U87 human malignant glioblastoma cells by suppression of anti-apoptotic signals and activation of cysteine proteases

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Lizarte, F.S. Neto; Tirapelli, D.P.C. [Universidade de São Paulo, Departamento de Cirurgia e Anatomia, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Ambrosio, S.R. [Universidade de Franca, Núcleo de Pesquisa em Ciências e Tecnologia, Franca, SP (Brazil); Tirapelli, C.R. [Universidade de São Paulo, Laboratório de Farmacologia, Departamento de Enfermagem Psiquiátrica e Ciências Humanas, Escola de Enfermagem de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Oliveira, F.M. [Universidade de São Paulo, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Novais, P.C. [Universidade de São Paulo, Departamento de Cirurgia e Anatomia, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Peria, F.M.; Oliveira, H.F. [Universidade de São Paulo, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Carlotti, C.G. Junior; Tirapelli, L.F. [Universidade de São Paulo, Departamento de Cirurgia e Anatomia, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil)

2013-01-11

Gliomas are the most common and malignant primary brain tumors in humans. Studies have shown that classes of kaurene diterpene have anti-tumor activity related to their ability to induce apoptosis. We investigated the response of the human glioblastoma cell line U87 to treatment with ent-kaur-16-en-19-oic acid (kaurenoic acid, KA). We analyzed cell survival and the induction of apoptosis using flow cytometry and annexin V staining. Additionally, the expression of anti-apoptotic (c-FLIP and miR-21) and apoptotic (Fas, caspase-3 and caspase-8) genes was analyzed by relative quantification (real-time PCR) of mRNA levels in U87 cells that were either untreated or treated with KA (30, 50, or 70 µM) for 24, 48, and 72 h. U87 cells treated with KA demonstrated reduced viability, and an increase in annexin V- and annexin V/PI-positive cells was observed. The percentage of apoptotic cells was 9% for control cells, 26% for cells submitted to 48 h of treatment with 50 µM KA, and 31% for cells submitted to 48 h of treatment with 70 µM KA. Similarly, in U87 cells treated with KA for 48 h, we observed an increase in the expression of apoptotic genes (caspase-8, -3) and a decrease in the expression of anti-apoptotic genes (miR-21 and c-FLIP). KA possesses several interesting properties and induces apoptosis through a unique mechanism. Further experiments will be necessary to determine if KA may be used as a lead compound for the development of new chemotherapeutic drugs for the treatment of primary brain tumors.

Kaurene diterpene induces apoptosis in U87 human malignant glioblastoma cells by suppression of anti-apoptotic signals and activation of cysteine proteases

International Nuclear Information System (INIS)

Lizarte, F.S. Neto; Tirapelli, D.P.C.; Ambrosio, S.R.; Tirapelli, C.R.; Oliveira, F.M.; Novais, P.C.; Peria, F.M.; Oliveira, H.F.; Carlotti, C.G. Junior; Tirapelli, L.F.

2013-01-01

Gliomas are the most common and malignant primary brain tumors in humans. Studies have shown that classes of kaurene diterpene have anti-tumor activity related to their ability to induce apoptosis. We investigated the response of the human glioblastoma cell line U87 to treatment with ent-kaur-16-en-19-oic acid (kaurenoic acid, KA). We analyzed cell survival and the induction of apoptosis using flow cytometry and annexin V staining. Additionally, the expression of anti-apoptotic (c-FLIP and miR-21) and apoptotic (Fas, caspase-3 and caspase-8) genes was analyzed by relative quantification (real-time PCR) of mRNA levels in U87 cells that were either untreated or treated with KA (30, 50, or 70 µM) for 24, 48, and 72 h. U87 cells treated with KA demonstrated reduced viability, and an increase in annexin V- and annexin V/PI-positive cells was observed. The percentage of apoptotic cells was 9% for control cells, 26% for cells submitted to 48 h of treatment with 50 µM KA, and 31% for cells submitted to 48 h of treatment with 70 µM KA. Similarly, in U87 cells treated with KA for 48 h, we observed an increase in the expression of apoptotic genes (caspase-8, -3) and a decrease in the expression of anti-apoptotic genes (miR-21 and c-FLIP). KA possesses several interesting properties and induces apoptosis through a unique mechanism. Further experiments will be necessary to determine if KA may be used as a lead compound for the development of new chemotherapeutic drugs for the treatment of primary brain tumors

Straw blood cell count, growth, inhibition and comparison to apoptotic bodies

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Tomkins Jeffrey P

2008-05-01

Full Text Available Abstract Background Mammalian cells transform into individual tubular straw cells naturally in tissues and in response to desiccation related stress in vitro. The transformation event is characterized by a dramatic cellular deformation process which includes: condensation of certain cellular materials into a much smaller tubular structure, synthesis of a tubular wall and growth of filamentous extensions. This study continues the characterization of straw cells in blood, as well as the mechanisms of tubular transformation in response to stress; with specific emphasis placed on investigating whether tubular transformation shares the same signaling pathway as apoptosis. Results There are approximately 100 billion, unconventional, tubular straw cells in human blood at any given time. The straw blood cell count (SBC is 45 million/ml, which accounts for 6.9% of the bloods dry weight. Straw cells originating from the lungs, liver and lymphocytes have varying nodules, hairiness and dimensions. Lipid profiling reveals severe disruption of the plasma membrane in CACO cells during transformation. The growth rates for the elongation of filaments and enlargement of rabbit straw cells is 0.6~1.1 (μm/hr and 3.8 (μm3/hr, respectively. Studies using apoptosis inhibitors and a tubular transformation inhibitor in CACO2 cells and in mice suggested apoptosis produced apoptotic bodies are mediated differently than tubular transformation produced straw cells. A single dose of 0.01 mg/kg/day of p38 MAPK inhibitor in wild type mice results in a 30% reduction in the SBC. In 9 domestic animals SBC appears to correlate inversely with an animal's average lifespan (R2 = 0.7. Conclusion Straw cells are observed residing in the mammalian blood with large quantities. Production of SBC appears to be constant for a given animal and may involve a stress-inducible protein kinase (P38 MAPK. Tubular transformation is a programmed cell survival process that diverges from apoptosis

Involvement of apoptotic cell death and cell cycle perturbation in retinoic acid-induced cleft palate in mice

International Nuclear Information System (INIS)

Okano, Junko; Suzuki, Shigehiko; Shiota, Kohei

2007-01-01

Retinoic acid (RA), a metabolite of vitamin A, plays a key role in a variety of biological processes and is essential for normal embryonic development. On the other hand, exogenous RA could cause cleft palate in offspring when it is given to pregnant animals at either the early or late phases of palatogenesis, but the pathogenetic mechanism of cleft palate caused by excess RA remains not fully elucidated. The aim of the present study was to investigate the effects of excess of RA on early palatogenesis in mouse fetuses and analyze the teratogenic mechanism, especially at the stage prior to palatal shelf elevation. We gave all-trans RA (100 mg/kg) orally to E11.5 ICR pregnant mice and observed the changes occurring in the palatal shelves of their fetuses. It was found that apoptotic cell death increased not only in the epithelium of the palatal shelves but also in the tongue primordium, which might affect tongue withdrawal movement during palatogenesis and impair the horizontal elevation of palatal shelves. In addition, RA was found to prevent the G 1 /S progression of palatal mesenchymal cells through upregulation of p21 Cip1 , leading to Rb hypophospholylation. Thus, RA appears to cause G 1 arrest in palatal mesenchymal cells in a similar manner as in various cancer and embryonic cells. It is likely that apoptotic cell death and cell cycle disruption are involved in cleft palate formation induced by RA

Reactive oxygen species are key mediators of the nitric oxide apoptotic pathway in anterior pituitary cells.

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Machiavelli, Leticia I; Poliandri, Ariel H; Quinteros, Fernanda A; Cabilla, Jimena P; Duvilanski, Beatriz H

2007-03-01

We previously showed that long-term exposure of anterior pituitary cells to nitric oxide (NO) induces apoptosis. The intracellular signals underlying this effect remained unclear. In this study, we searched for possible mechanisms involved in the early stages of the NO apoptotic cascade. Caspase 3 was activated by NO with no apparent disruption of mitochondrial membrane potential. NO caused a rapid increase of reactive oxygen species (ROS), and this increase seems to be dependent of mitochondrial electron transport chain. The antioxidant N-acetyl-cysteine avoided ROS increase, prevented the NO-induced caspase 3 activation, and reduced the NO apoptotic effect. Catalase was inactivated by NO, while glutathione peroxidase (GPx) activity and reduced glutathione (GSH) were not modified at first, but increased at later times of NO exposure. The increase of GSH level is important for the scavenging of the NO-induced ROS overproduction. Our results indicate that ROS have an essential role as a trigger of the NO apoptotic cascade in anterior pituitary cells. The permanent inhibition of catalase may strengthen the oxidative damage induced by NO. GPx activity and GSH level augment in response to the oxidative damage, though this increase seems not to be enough to rescue the cells from the NO effect.

Proposed Pharmacological Countermeasures Against Apoptotic Cell Death in Experimental Models Mimicking Space Environment Damage

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Lulli, Matteo; Papucci, Laura; Witort, Ewa; Donnini, Martino; Lapucci, Andrea; Lazzarano, Stefano; Mazzoni, Tiziano; Simoncini, Madine; Falciani, Piergiuseppe; Capaccioli, Sergio

2008-06-01

Several damaging agents have been suggested to affect human vision during long term space travels. Recently, apoptosis induced by DNA-damaging agents has emerged as frequent pathogenetic mechanism of ophthalmologic pathologies. Here, we propose two countermeasures: coenzyme Q10 and bcl-2 downregulation preventing antisense oligoribonucleotides (ORNs), aimed to inhibit cellular apoptotic death. Our studies have been carried out on retina and neuronal cultured cells treated with the following apoptotic stimuli mimicking space environment: a several-day exposure to either 3H-labeled tymidine or to the genotoxic drug doxorubicin, UV irradiation, hypoxia and glucose/growth factor starvation (Locke medium). The preliminary results clearly indicate that CoQ10, as well as bcl-2 down-regulation preventing ORNs, significantly counteract apoptosis in response to different DNA damaging agents in cultured eye and in neuronal cells. This supports the possibility that both could be optimal countermeasures against ophthalmologic lesions during space explorations.

Targeting Toll-like receptor 7/8 enhances uptake of apoptotic leukemic cells by monocyte-derived dendritic cells but interferes with subsequent cytokine-induced maturation.

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van den Ancker, Willemijn; van Luijn, Marvin M; Ruben, Jurjen M; Westers, Theresia M; Bontkes, Hetty J; Ossenkoppele, Gert J; de Gruijl, Tanja D; van de Loosdrecht, Arjan A

2011-01-01

Therapeutic vaccination with dendritic cells (DC) is an emerging investigational therapy for eradication of minimal residual disease in acute myeloid leukemia. Various strategies are being explored in manufacturing DC vaccines ex vivo, e.g., monocyte-derived DC (MoDC) loaded with leukemia-associated antigens (LAA). However, the optimal source of LAA and the choice of DC-activating stimuli are still not well defined. Here, loading with leukemic cell preparations (harboring both unknown and known LAA) was explored in combination with a DC maturation-inducing cytokine cocktail (CC; IL-1β, IL-6, TNF-α, and PGE(2)) and Toll-like receptor ligands (TLR-L) to optimize uptake. Since heat shock induced apoptotic blasts were more efficiently taken up than lysates, we focused on uptake of apoptotic leukemic cells. Uptake of apoptotic blast was further enhanced by the TLR7/8-L R848 (20-30%); in contrast, CC-induced maturation inhibited uptake. CC, and to a lesser extent R848, enhanced the ability of MoDC to migrate and stimulate T cells. Furthermore, class II-associated invariant chain peptide expression was down-modulated after R848- or CC-induced maturation, indicating enhanced processing and presentation of antigenic peptides. To improve both uptake and maturation, leukemic cells and MoDC were co-incubated with R848 for 24 h followed by addition of CC. However, this approach interfered with CC-mediated MoDC maturation as indicated by diminished migratory and T cell stimulatory capacity, and the absence of IL-12 production. Taken together, our data demonstrate that even though R848 improved uptake of apoptotic leukemic cells, the sequential use of R848 and CC is counter-indicated due to its adverse effects on MoDC maturation.

dp53 Restrains ectopic neural stem cell formation in the Drosophila brain in a non-apoptotic mechanism involving Archipelago and cyclin E.

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Yingshi Ouyang

Full Text Available Accumulating evidence suggests that tumor-initiating stem cells or cancer stem cells (CSCs possibly originating from normal stem cells may be the root cause of certain malignancies. How stem cell homeostasis is impaired in tumor tissues is not well understood, although certain tumor suppressors have been implicated. In this study, we use the Drosophila neural stem cells (NSCs called neuroblasts as a model to study this process. Loss-of-function of Numb, a key cell fate determinant with well-conserved mammalian counterparts, leads to the formation of ectopic neuroblasts and a tumor phenotype in the larval brain. Overexpression of the Drosophila tumor suppressor p53 (dp53 was able to suppress ectopic neuroblast formation caused by numb loss-of-function. This occurred in a non-apoptotic manner and was independent of Dacapo, the fly counterpart of the well-characterized mammalian p53 target p21 involved in cellular senescence. The observation that dp53 affected Edu incorporation into neuroblasts led us to test the hypothesis that dp53 acts through regulation of factors involved in cell cycle progression. Our results show that the inhibitory effect of dp53 on ectopic neuroblast formation was mediated largely through its regulation of Cyclin E (Cyc E. Overexpression of Cyc E was able to abrogate dp53's ability to rescue numb loss-of-function phenotypes. Increasing Cyc E levels by attenuating Archipelago (Ago, a recently identified transcriptional target of dp53 and a negative regulator of Cyc E, had similar effects. Conversely, reducing Cyc E activity by overexpressing Ago blocked ectopic neuroblast formation in numb mutant. Our results reveal an intimate connection between cell cycle progression and NSC self-renewal vs. differentiation control, and indicate that p53-mediated regulation of ectopic NSC self-renewal through the Ago/Cyc E axis becomes particularly important when NSC homeostasis is perturbed as in numb loss-of-function condition. This has

Exocytosis of macrophage lysosomes leads to digestion of apoptotic adipocytes and foam cell formation[S

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Haka, Abigail S.; Barbosa-Lorenzi, Valéria C.; Lee, Hyuek Jong; Falcone, Domenick J.; Hudis, Clifford A.; Dannenberg, Andrew J.

2016-01-01

Many types of apoptotic cells are phagocytosed and digested by macrophages. Adipocytes can be hundreds of times larger than macrophages, so they are too large to be digested by conventional phagocytic processes. The nature of the interaction between macrophages and apoptotic adipocytes has not been studied in detail. We describe a cellular process, termed exophagy, that is important for macrophage clearance of dead adipocytes and adipose tissue homeostasis. Using mouse models of obesity, human tissue, and a cell culture model, we show that macrophages form hydrolytic extracellular compartments at points of contact with dead adipocytes using local actin polymerization. These compartments are acidic and contain lysosomal enzymes delivered by exocytosis. Uptake and complete degradation of adipocyte fragments, which are released by extracellular hydrolysis, leads to macrophage foam cell formation. Exophagy-mediated foam cell formation is a highly efficient means by which macrophages internalize large amounts of lipid, which may ultimately overwhelm the metabolic capacity of the macrophage. This process provides a mechanism for degradation of objects, such as dead adipocytes, that are too large to be phagocytosed by macrophages. PMID:27044658

BAD-mediated apoptotic pathway is associated with human cancer development.

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Stickles, Xiaomang B; Marchion, Douglas C; Bicaku, Elona; Al Sawah, Entidhar; Abbasi, Forough; Xiong, Yin; Bou Zgheib, Nadim; Boac, Bernadette M; Orr, Brian C; Judson, Patricia L; Berry, Amy; Hakam, Ardeshir; Wenham, Robert M; Apte, Sachin M; Berglund, Anders E; Lancaster, Johnathan M

2015-04-01

The malignant transformation of normal cells is caused in part by aberrant gene expression disrupting the regulation of cell proliferation, apoptosis, senescence and DNA repair. Evidence suggests that the Bcl-2 antagonist of cell death (BAD)-mediated apoptotic pathway influences cancer chemoresistance. In the present study, we explored the role of the BAD-mediated apoptotic pathway in the development and progression of cancer. Using principal component analysis to derive a numeric score representing pathway expression, we evaluated clinico-genomic datasets (n=427) from corresponding normal, pre-invasive and invasive cancers of different types, such as ovarian, endometrial, breast and colon cancers in order to determine the associations between the BAD-mediated apoptotic pathway and cancer development. Immunofluorescence was used to compare the expression levels of phosphorylated BAD [pBAD (serine-112, -136 and -155)] in immortalized normal and invasive ovarian, colon and breast cancer cells. The expression of the BAD-mediated apoptotic pathway phosphatase, PP2C, was evaluated by RT-qPCR in the normal and ovarian cancer tissue samples. The growth-promoting effects of pBAD protein levels in the immortalized normal and cancer cells were assessed using siRNA depletion experiments with MTS assays. The expression of the BAD-mediated apoptotic pathway was associated with the development and/or progression of ovarian (n=106, pBAD-mediated apoptotic pathway is thus associated with the development of human cancers likely influenced by the protein levels of pBAD.

Primula auriculata Extracts Exert Cytotoxic and Apoptotic Effects against HT-29 Human Colon Adenocarcinoma Cells.

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Behzad, Sahar; Ebrahim, Karim; Mosaddegh, Mahmoud; Haeri, Ali

2016-01-01

Primula auriculata (Tootia) is one of the most important local medicinal plants in Hamedan district, Iran. To investigate cytotoxicity and apoptosis induction of crude methanolic extract and different fraction of it, we compared several methods on HT-29 human colon Adenocarcinoma cells. Cancer cell proliferation was measured by 3-(4, 5‑dimethylthiazolyl)2, 5‑diphenyl‑tetrazolium bromide (MTT) assay and apoptosis induction was analyzed by fluorescence microscopy (acridin orange/ethidium bromide, annexin V/propidium iodide staining, TUNEL assay and Caspase-3 activity assay). Crude methanolic extract (CM) inhibited the growth of malignant cells in a dose-dependent manner. Among solvent fractions, the dichloromethane fraction (CF) was found to be the most toxic compared to other fractions. With double staining methods, high percentage of 40 µg/mL of (CM) and (CF) treated cells exhibited typical characteristics of apoptotic cells. Apoptosis induction was also revealed by apoptotic fragmentation of nuclear DNA and activation of caspas-3 in treated cells. These findings indicate that crude methanolic extract and dichloromethan fraction of P.auriculata induced apoptosis and inhibited proliferation in colon cancer cells and could be used as a source for new lead structures in drug design to combat colon cancer.

C1q protein binds to the apoptotic nucleolus and causes C1 protease degradation of nucleolar proteins.

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Cai, Yitian; Teo, Boon Heng Dennis; Yeo, Joo Guan; Lu, Jinhua

2015-09-11

In infection, complement C1q recognizes pathogen-congregated antibodies and elicits complement activation. Among endogenous ligands, C1q binds to DNA and apoptotic cells, but whether C1q binds to nuclear DNA in apoptotic cells remains to be investigated. With UV irradiation-induced apoptosis, C1q initially bound to peripheral cellular regions in early apoptotic cells. By 6 h, binding concentrated in the nuclei to the nucleolus but not the chromatins. When nucleoli were isolated from non-apoptotic cells, C1q also bound to these structures. In vivo, C1q exists as the C1 complex (C1qC1r2C1s2), and C1q binding to ligands activates the C1r/C1s proteases. Incubation of nucleoli with C1 caused degradation of the nucleolar proteins nucleolin and nucleophosmin 1. This was inhibited by the C1 inhibitor. The nucleoli are abundant with autoantigens. C1q binding and C1r/C1s degradation of nucleolar antigens during cell apoptosis potentially reduces autoimmunity. These findings help us to understand why genetic C1q and C1r/C1s deficiencies cause systemic lupus erythematosus. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

TNF alpha induces ABCA1 through NF-kappa B in macrophages and in phagocytes ingesting apoptotic cells

NARCIS (Netherlands)

Gerbod-Giannone, Marie-Christine; Li, Yankun; Holleboom, Adriaan; Han, Seongah; Hsu, Li-Chung; Tabas, Ira; Tall, Alan R.

2006-01-01

Recent evidence suggests that tumor necrosis factor alpha (TNF alpha) signaling in vascular cells can have antiatherogenic consequences, but the mechanisms are poorly understood. TNFa is released by free cholesterol loaded apoptotic macrophages, and the clearance of these cells by phagocytic

Metal stress induces programmed cell death in aquatic fungi

International Nuclear Information System (INIS)

Azevedo, Maria-Manuel; Almeida, Bruno; Ludovico, Paula; Cassio, Fernanda

2009-01-01

Aquatic hyphomycetes are a group of fungi that play a key role in organic matter turnover in both clean and metal-polluted streams. We examined the ability of Cu or Zn to induce programmed cell death (PCD) in three aquatic hyphomycete species through the evaluation of typical apoptotic markers, namely reactive oxygen species (ROS) accumulation, caspase-like activity, nuclear morphological alterations, and the occurrence of DNA strand breaks assessed by TUNEL assay. The exposure to both metals induced apoptotic events in all tested aquatic fungi. The most tolerant fungi either to Zn (Varicosporium elodeae) or Cu (Heliscussubmersus) exhibited higher levels of PCD markers, suggesting that PCD processes might be linked to fungal resistance/tolerance to metal stress. Moreover, different patterns of apoptotic markers were found, namely a PCD process independent of ROS accumulation in V. elodeae exposed to Cu, or independent of caspase-like activity in Flagellospora curta exposed to Zn, or even without the occurrence of DNA strand breaks in F. curta exposed to Cu. This suggests that a multiplicity of PCD pathways might be operating in aquatic hyphomycetes. The occurrence of a tightly regulated cell death pathway, such as PCD, in aquatic hyphomycetes under metal stress might be a part of the mechanisms underlying fungal acclimation in metal-polluted streams, because it would allow the rapid removal of unwanted or damaged cells sparing nutrients and space for the fittest ones.

Increase in the fraction of necrotic, not apoptotic, cells in SiHa xenograft tumours shortly after irradiation

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Olive, P.L.; Vikse, C.M.; Vanderbyl, S.

1999-01-01

Background and purpose: Approximately 18% of the cells recovered by rapid mechanical dissociation of SiHa xenograft tumours contain large numbers of DNA strand breaks. The number of damaged cells increases to 30-40% 4-6 h after exposure to 5 or 15 Gy, returning to normal levels by 12 h. This observation is reminiscent of the rate of production of apoptotic cells in other murine and human xenograft tumours. The nature of this damage, rate of development and relation to cell proliferation rate were therefore examined in detail.Materials and methods: SiHa human cervical carcinoma cells were grown as xenograft tumours in SCID mice. Single-cell suspensions were prepared as a function of time after irradiation of the mouse and examined for DNA damage using the alkaline comet assay. Cell cycle progression was measured by flow cytometry evaluation of anti-bromodeoxyuridine-labelled tumour cells.Results: Significant numbers of apoptotic cells could not be detected in irradiated SiHa tumours using an end-labelling assay, electron microscopy, or histological examination of thin sections. Instead, xenograft cells exhibiting extensive DNA damage in the comet assay were predominantly necrotic cells. The increase in the proportion of heavily damaged cells 4-6 h after irradiation could be the result of an interplay between several factors including loss of viable cells and change in production or loss of necrotic cells. Analysis of the progression of BrdUrd-labelled cells confirmed that while 35% of cells from untreated SiHa tumours had divided and entered G 1 phase by 6 h after BrdUrd injection, none of the labelled cells from tumours exposed to 5 or 15 Gy had progressed to G 1 .Conclusions: The increase in the percentage of SiHa tumour cells with extensive DNA damage 4-6 h after irradiation is attributable to necrosis, not apoptosis. Cell cycle progression and cell loss are likely to influence the kinetics of appearance of both apoptotic and necrotic cells in irradiated tumours

Pro-apoptotic signaling induced by Retinoic acid and dsRNA is under the control of Interferon Regulatory Factor-3 in breast cancer cells.

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Bernardo, Ana R; Cosgaya, José M; Aranda, Ana; Jiménez-Lara, Ana M

2017-07-01

Breast cancer is one of the most lethal malignancies for women. Retinoic acid (RA) and double-stranded RNA (dsRNA) are considered signaling molecules with potential anticancer activity. RA, co-administered with the dsRNA mimic polyinosinic-polycytidylic acid (poly(I:C)), synergizes to induce a TRAIL (Tumor-Necrosis-Factor Related Apoptosis-Inducing Ligand)- dependent apoptotic program in breast cancer cells. Here, we report that RA/poly(I:C) co-treatment, synergically, induce the activation of Interferon Regulatory Factor-3 (IRF3) in breast cancer cells. IRF3 activation is mediated by a member of the pathogen recognition receptors, Toll-like receptor-3 (TLR3), since its depletion abrogates IRF3 activation by RA/poly(I:C) co-treatment. Besides induction of TRAIL, apoptosis induced by RA/poly(I:C) correlates with the increased expression of pro-apoptotic TRAIL receptors, TRAIL-R1/2, and the inhibition of the antagonistic receptors TRAIL-R3/4. IRF3 plays an important role in RA/poly(I:C)-induced apoptosis since IRF3 depletion suppresses caspase-8 and caspase-3 activation, TRAIL expression upregulation and apoptosis. Interestingly, RA/poly(I:C) combination synergizes to induce a bioactive autocrine/paracrine loop of type-I Interferons (IFNs) which is ultimately responsible for TRAIL and TRAIL-R1/2 expression upregulation, while inhibition of TRAIL-R3/4 expression is type-I IFN-independent. Our results highlight the importance of IRF3 and type-I IFNs signaling for the pro-apoptotic effects induced by RA and synthetic dsRNA in breast cancer cells.

Caffeine Induces Cell Death via Activation of Apoptotic Signal and Inactivation of Survival Signal in Human Osteoblasts

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Wen-Hsiung Chan

2008-05-01

Full Text Available Caffeine consumption is a risk factor for osteoporosis, but the precise regulatory mechanisms are currently unknown. Here, we show that cell viability decreases in osteoblasts treated with caffeine in a dose-dependent manner. This cell death is attributed primarily to apoptosis and to a smaller extent, necrosis. Moreover, caffeine directly stimulates intracellular oxidative stress. Our data support caffeine-induced apoptosis in osteoblasts via a mitochondria-dependent pathway. The apoptotic biochemical changes were effectively prevented upon pretreatment with ROS scavengers, indicating that ROS plays a critical role as an upstream controller in the caffeine-induced apoptotic cascade. Additionally, p21-activated protein kinase 2 (PAK2 and c-Jun N-terminal kinase (JNK were activated in caffeine-treated osteoblasts. Experiments further found that PAK2 activity is required for caffeine-induced JNK activation and apoptosis. Importantly, our data also show that caffeine triggers cell death via inactivation of the survival signal, including the ERK- and Akt-mediated anti-apoptotic pathways. Finally, exposure of rats to dietary water containing 10~20 μM caffeine led to bone mineral density loss. These results demonstrate for the first time that caffeine triggers apoptosis in osteoblasts via activation of mitochondria-dependent cell death signaling and inactivation of the survival signal, and causes bone mineral density loss in vivo.

Freezing and post-thaw apoptotic behaviour of cells in the presence of palmitoyl nanogold particles

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Thirumala, Sreedhar; Forman, Julianne M; Monroe, W Todd; Devireddy, Ram V

2007-01-01

The aim of this study was to evaluate the freezing response of HeLa and Jurkat cells in the presence of commercially available nanoparticles, NPs (Palmitoyl Nanogold[reg], Nanoprobes). The cells were incubated with NPs for either 5 min or 3 h, and a calorimeter technique was then used to generate the volumetric shrinkage response during freezing at 20 deg. C min -1 . Concomitantly, we also examined the effect of a commonly used cryoprotectant, dimethylsulfoxide, DMSO (10% v/v ratio) on the freezing response of HeLa and Jurkat cells. By fitting a model of water transport to the experimentally determined volumetric shrinkage data, the reference hydraulic conductivity, L pg (μm/min-atm) and activation energy, E Lp (kcal mol -1 ) were obtained. For HeLa cells, the values of L pg ranged from 0.08 to 0.23 μm/min-atm, while E Lp ranged from 10.9 to 37.4 kcal mol -1 . For Jurkat cells these parameter values ranged from 0.05 to 0.16 μm/min-atm and 9.5 to 35.9 kcal mol -1 . A generic optimal cooling rate equation was then used to predict the optimal rates of freezing HeLa and Jurkat cells in the presence and absence of DMSO and NPs. The post-thaw viability and apoptotic response of HeLa and Jurkat cells was further investigated by cooling cells at three rates in the presence and absence of DMSO and NPs using a commercially available controlled rate freezer. Jurkat cells treated in this manner demonstrated an increase in their adhesive properties after 18 h incubation and adhered strongly to the bottom of the culture plate. This observation prevented further analysis of Jurkat apoptotic and necrotic post-thaw responses. There was no significant effect of NPs or DMSO alone on HeLa cell viability prior to freezing. The post-thaw results from HeLa cells show that the NPs increased the measured post-freeze apoptotic response when cooled at 1 deg. C min -1 , suggesting a possible therapeutic use of NPs in cryodestructive procedures

Mis-targeting of the mitochondrial protein LIPT2 leads to apoptotic cell death.

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Emanuele Bernardinelli

Full Text Available Lipoyl(Octanoyl Transferase 2 (LIPT2 is a protein involved in the post-translational modification of key energy metabolism enzymes in humans. Defects of lipoic acid synthesis and transfer start to emerge as causes of fatal or severe early-onset disease. We show that the first 31 amino acids of the N-terminus of LIPT2 represent a mitochondrial targeting sequence and inhibition of the transit of LIPT2 to the mitochondrion results in apoptotic cell death associated with activation of the apoptotic volume decrease (AVD current in normotonic conditions, as well as over-activation of the swelling-activated chloride current (IClswell, mitochondrial membrane potential collapse, caspase-3 cleavage and nuclear DNA fragmentation. The findings presented here may help elucidate the molecular mechanisms underlying derangements of lipoic acid biosynthesis.

Efficient internalization of mesoporous silica particles of different sizes by primary human macrophages without impairment of macrophage clearance of apoptotic or antibody-opsonized target cells

International Nuclear Information System (INIS)

Witasp, Erika; Kupferschmidt, Natalia; Bengtsson, Linnea; Hultenby, Kjell; Smedman, Christian; Paulie, Staffan; Garcia-Bennett, Alfonso E.; Fadeel, Bengt

2009-01-01

Macrophage recognition and ingestion of apoptotic cell corpses, a process referred to as programmed cell clearance, is of considerable importance for the maintenance of tissue homeostasis and in the resolution of inflammation. Moreover, macrophages are the first line of defense against microorganisms and other foreign materials including particles. However, there is sparse information on the mode of uptake of engineered nanomaterials by primary macrophages. In this study, mesoporous silica particles with cubic pore geometries and covalently fluorescein-grafted particles were synthesized through a novel route, and their interactions with primary human monocyte-derived macrophages were assessed. Efficient and active internalization of mesoporous silica particles of different sizes was observed by transmission electron microscopic and flow cytometric analysis and studies using pharmacological inhibitors suggested that uptake occurred through a process of endocytosis. Moreover, uptake of silica particles was independent of serum factors. The silica particles with very high surface areas due to their porous structure did not impair cell viability or function of macrophages, including the ingestion of different classes of apoptotic or opsonized target cells. The current findings are relevant to the development of mesoporous materials for drug delivery and other biomedical applications.

Study of morphological changes in breast cancer cells MCF-7 under the action of pro-apoptotic agents with laser modulation interference microscope MIM-340

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Nebogatikov, V.; Nikitiuk, A.; Konysheva, A.; Ignatyev, P.; Grishko, V.; Naimark, O.

2017-09-01

Quantitative phase microscopy is a new method to measure and evaluate the microlevel processes characterized by the high resolution and providing ample opportunities to quantitatively analyze various parameters, including specimens from biological matter. In this study, a laser interference microscope was used to evaluate the state of cancer cells (living and apoptotic). Apoptotic cancer cells were obtained by treatment of MCF-7 cells with the use of betulin-based α-bromomethyl ketone (BMK) derivative. When using the microscope, the main differences in the morphometric parameters of living and apoptotic cells such as height, diameter, perimeter, area and volume were appraised. The criteria that can be used as markers of apoptosis activation were identified.

TIPE attenuates the apoptotic effect of radiation and cisplatin and promotes tumor growth via JNK and p38 activation in Raw264.7 and EL4 cells.

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Liu, Yao; Ni, Xiao Yan; Chen, Rui Ling; Li, Juan; Gao, Feng Guang

2018-06-01

Tumor necrosis factor α‑induced protein 8 (TIPE) is highly expressed in many types of malignancies. Apoptosis is the process of programmed cell death which maintains the balance of cell survival and death. TIPE is involved in the carcinogenesis of many tumor types, yet the exact role of TIPE in defective apoptosis‑associated carcinogenesis remains uncertain. In the present study, TIPE‑overexpressing Raw264.7 and EL4 cells and vector control cells were treated with 4 mJ/cm2 ultraviolet radiation or 2 µg/ml cisplatin. Following ultraviolet irradiation, TIPE overexpression decreased the percentage of apoptotic cells as detected by flow cytometric and reversed the cisplatin‑mediated decrease in mitochondrial membrane potential by JC‑1 assay. Western blot analyses also revealed that TIPE overexpression inhibited cisplatin‑induced activation of caspase‑3 and ‑9 and PARP. Secondly, TIPE overexpression increased the levels of phosphorylated JNK, MEK and p38. Moreover, inhibition of JNK and p38, but not MEK, efficiently abolished the cell pro‑survival effect of TIPE. Most importantly, an in vivo tumor implantation model revealed that TIPE overexpression augmented the volume and weight of the implanted tumors, indicating that TIPE facilitated tumor formation. We found that TIPE exhibited an anti‑apoptotic effect via JNK and p38 activation, which ultimately promoted tumor. Hence, the present study revealed that activation of JNK and p38 kinases contribute to the TIPE‑mediated anti‑apoptotic effect, indicating that JNK and p38 may be potential therapeutic molecules for TIPE overexpression‑associated diseases.

Cannabidiol restores intestinal barrier dysfunction and inhibits the apoptotic process induced by Clostridium difficile toxin A in Caco-2 cells.

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Gigli, Stefano; Seguella, Luisa; Pesce, Marcella; Bruzzese, Eugenia; D'Alessandro, Alessandra; Cuomo, Rosario; Steardo, Luca; Sarnelli, Giovanni; Esposito, Giuseppe

2017-12-01

Clostridium difficile toxin A is responsible for colonic damage observed in infected patients. Drugs able to restore Clostridium difficile toxin A-induced toxicity have the potential to improve the recovery of infected patients. Cannabidiol is a non-psychotropic component of Cannabis sativa, which has been demonstrated to protect enterocytes against chemical and/or inflammatory damage and to restore intestinal mucosa integrity. The purpose of this study was to evaluate (a) the anti-apoptotic effect and (b) the mechanisms by which cannabidiol protects mucosal integrity in Caco-2 cells exposed to Clostridium difficile toxin A. Caco-2 cells were exposed to Clostridium difficile toxin A (30 ng/ml), with or without cannabidiol (10 -7 -10 -9  M), in the presence of the specific antagonist AM251 (10 -7  M). Cytotoxicity assay, transepithelial electrical resistence measurements, immunofluorescence analysis and immunoblot analysis were performed in the different experimental conditions. Clostridium difficile toxin A significantly decreased Caco-2 cells' viability and reduced transepithelial electrical resistence values and RhoA guanosine triphosphate (GTP), bax, zonula occludens-1 and occludin protein expression, respectively. All these effects were significantly and concentration-dependently inhibited by cannabidiol, whose effects were completely abolished in the presence of the cannabinoid receptor type 1 (CB1) antagonist, AM251. Cannabidiol improved Clostridium difficile toxin A-induced damage in Caco-2 cells, by inhibiting the apoptotic process and restoring the intestinal barrier integrity, through the involvement of the CB1 receptor.

Activated cathepsin L is associated with the switch from autophagy to apoptotic death of SH-SY5Y cells exposed to 6-hydroxydopamine

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Li, Lingyun, E-mail: lingyunlee@126.com [Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123 (China); Experimental Center, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Gao, Luyan [Experimental Center, The Second Affiliated Hospital of Soochow University, Suzhou 215004 (China); Song, Yunzhen; Qin, Zheng-Hong [Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123 (China); Liang, Zhongqin, E-mail: liangzhongqin@suda.edu.cn [Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123 (China)

2016-02-12

Autophagy and apoptosis are common responses to pathological damage in the process of Parkinson's disease (PD), and lysosome dysfunction may contribute to the etiology of PD's neurodegenerative process. In this study, we demonstrated that the neurotoxin 6-hydroxydopamine (6-OHDA) increased autophagy in SH-SY5Y cells, as determined by detection of the lysosome marker lysosomal-associated membrane protein1, the autophagy protein light chain 3 (LC3)-II and the autophagy substrate P62 protein. Meanwhile, autophagy repression with 3-methyladenine accelerated the activation of caspase-3 and PARP and aggravated the cell apoptotic death induced by 6-OHDA. Furthermore, we found that 6-OHDA treatment resulted in a transient increase in the intracellular and nuclear expression of cathepsin L (CTSL). The CTSL inhibitor, Z-FY-CHO, could promote autophagy, decrease accumulation of P62, and block activation of caspase-3 and PARP. Taken together, these results suggest that activation of autophagy may primarily be a protective process in SH-SY5Y cell death induced by 6-OHDA, and the nuclear translocation of CTSL could enhance the cell apoptotic cascade via disturbing autophagy-apoptotic systems in SH-SY5Y cells. Our findings highlight the potential role of CTSL in the cross talk between autophagy and apoptosis, which might be considered a therapeutic strategy for treatment of pathologic conditions associated with neurodegeneration. - Highlights: • Inhibition of autophagy aggravated the cell apoptotic death in SH-SY5Y cells. • Activation of cathepsin L impaired the autophagy pathway. • Activation of cathepsin L enhanced the cell apoptotic cascade. • Cathepsin L involves in the cross talk between autophagy and apoptosis.

A BioDesign Approach to Obtain High Yields of Biosimilars by Anti-apoptotic Cell Engineering: a Case Study to Increase the Production Yield of Anti-TNF Alpha Producing Recombinant CHO Cells.

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Gulce Iz, Sultan; Inevi, Muge Anil; Metiner, Pelin Saglam; Tamis, Duygu Ayyildiz; Kisbet, Nazli

2018-01-01

Recent developments in medical biotechnology have facilitated to enhance the production of monoclonal antibodies (mAbs) and recombinant proteins in mammalian cells. Human mAbs for clinical applications have focused on three areas, particularly cancer, immunological disorders, and infectious diseases. Tumor necrosis factor alpha (TNF-α), which has both proinflammatory and immunoregulatory functions, is an important target in biopharmaceutical industry. In this study, a humanized anti-TNF-α mAb producing stable CHO cell line which produces a biosimilar of Humira (adalimumab) was used. Adalimumab is a fully human anti-TNF mAb among the top-selling mAb products in recent years as a biosimilar. Products from mammalian cell bioprocesses are a derivative of cell viability and metabolism, which is mainly disrupted by cell death in bioreactors. Thus, different strategies are used to increase the product yield. Suppression of apoptosis, also called anti-apoptotic cell engineering, is the most remarkable strategy to enhance lifetime of cells for a longer production period. In fact, using anti-apoptotic cell engineering as a BioDesign approach was inspired by nature; nature gives prolonged life span to some cells like stem cells, tumor cells, and memory B and T cells, and researchers have been using this strategy for different purposes. In this study, as a biomimicry approach, anti-apoptotic cell engineering was used to increase the anti-TNF-α mAb production from the humanized anti-TNF-α mAb producing stable CHO cell line by Bcl-xL anti-apoptotic protein. It was shown that transient transfection of CHO cells by the Bcl-xL anti-apoptotic protein expressing plasmid prolonged the cell survival rate and protected cells from apoptosis. The transient expression of Bcl-xL using CHO cells enhanced the anti-TNF-α production. The production of anti-TNF-α in CHO cells was increased up to 215 mg/L with an increase of 160% after cells were transfected with Bcl-xL expressing plasmid

Mitochondrial fission proteins regulate programmed cell death in yeast.

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Fannjiang, Yihru; Cheng, Wen-Chih; Lee, Sarah J; Qi, Bing; Pevsner, Jonathan; McCaffery, J Michael; Hill, R Blake; Basañez, Gorka; Hardwick, J Marie

2004-11-15

The possibility that single-cell organisms undergo programmed cell death has been questioned in part because they lack several key components of the mammalian cell death machinery. However, yeast encode a homolog of human Drp1, a mitochondrial fission protein that was shown previously to promote mammalian cell death and the excessive mitochondrial fragmentation characteristic of apoptotic mammalian cells. In support of a primordial origin of programmed cell death involving mitochondria, we found that the Saccharomyces cerevisiae homolog of human Drp1, Dnm1, promotes mitochondrial fragmentation/degradation and cell death following treatment with several death stimuli. Two Dnm1-interacting factors also regulate yeast cell death. The WD40 repeat protein Mdv1/Net2 promotes cell death, consistent with its role in mitochondrial fission. In contrast to its fission function in healthy cells, Fis1 unexpectedly inhibits Dnm1-mediated mitochondrial fission and cysteine protease-dependent cell death in yeast. Furthermore, the ability of yeast Fis1 to inhibit mitochondrial fission and cell death can be functionally replaced by human Bcl-2 and Bcl-xL. Together, these findings indicate that yeast and mammalian cells have a conserved programmed death pathway regulated by a common molecular component, Drp1/Dnm1, that is inhibited by a Bcl-2-like function.

Peptide-Based Photoelectrochemical Cytosensor Using a Hollow-TiO2/EG/ZnIn2S4 Cosensitized Structure for Ultrasensitive Detection of Early Apoptotic Cells and Drug Evaluation.

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Wu, Rong; Fan, Gao-Chao; Jiang, Li-Ping; Zhu, Jun-Jie

2018-02-07

The ability to rapidly detect apoptotic cells and accurately evaluate therapeutic effects is significant in cancer research. To address this target, a biocompatible, ultrasensitive photoelectrochemical (PEC) cytosensing platform was developed based on electrochemically reduced graphene (EG)/ZnIn 2 S 4 cosensitized TiO 2 coupled with specific recognition between apoptotic cells and phosphatidylserine-binding peptide (PSBP). In this strategy, the HL-60 cells were selected as a model and C005, nilotinib, and imatinib were selected as apoptosis inducers to show cytosensing performances. In particular, a TiO 2 photoactive substrate was designed as hollow spheres to enhance the PEC performance. Graphene was electrodeposited on the hollow TiO 2 -modified electrode to accelerate electron transfer and increase conductivity, followed by in situ growth of ZnIn 2 S 4 nanocrystals as photosensitizers via successive ionic layer adsorption and reaction method, forming a TiO 2 /EG/ZnIn 2 S 4 cosensitized structure that was used as a PEC matrix to immobilize PSBP for the recognition of early apoptotic cells. The detection of apoptotic cells was based on steric hindrance originating from apoptotic cell capture to induce an obvious decrease in the photocurrent signal. The ultrahigh sensitivity of the cytosensor resulted from enhanced PEC performance, bioactivity, and high binding affinity between PSBP and apoptotic cells. Compared with other assays, incorporate toxic elements were avoided, such as Cd, Ru, and Te, which ensured normal cell growth and are appropriate for cell analysis. The designed PEC cytosensor showed a low detection limit of apoptotic cells (as low as three cells), a wide linear range from 1 × 10 3 to 5 × 10 7 cells/mL, and an accurate evaluation of therapeutic effects. It also exhibited good specificity, reproducibility, and stability.

To the nucleolar density and size in apoptotic human leukemic myeloblasts produced in vitro by Trichostatin A

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K Smetana

2009-08-01

Full Text Available The present study was designed to provide more information on nucleoli in apoptotic cells, which were represented in the present study by cultured leukemic myeloblasts (Kasumi-1 cells. The apoptotic process in these cells was produced by trichostatin A (TSA that is a histone deacetylase inhibitor with strong cytostatic effects. The selected TSA concentration added to cultures facilitated to study apoptotic and notapoptotic cells in one and the same specimen. The nucleolar diameter and density were determined using computer assisted measurement and densitometry in specimens stained for RNA. In comparison with not-apoptotic cells, in apoptotic cells, nucleolar mean diameter did not change significantly and nucleolar RNA density was also not apparently different. On the other hand, the cytoplasmic RNA density in apoptotic cells was markedly reduced. Thus it seemed to be possible that the transcribed RNA remained “frozen” within the nucleolus but its transport to the cytoplasm decreased or stopped. However, the possibility of the RNA degradation in the cytoplasm of apoptotic cells based on the present study cannot be eliminated. At this occasion it should be added that AgNORs reflecting nucleolar biosynthetic and cell proliferation activity in apoptotic cells decreased in number or disappeared. The presented results also indicated that large nucleoli intensely stained for RNA need not be necessarily related to the high nucleolar biosynthetic or cell proliferation activity and may be also present in apoptotic cells responding to the cytostatic treatment.

WNT7b mediates macrophage-induced programmed cell death in patterning of the vasculature

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Lobov, Ivan B.; Rao, Sujata; Carroll, Thomas J.; Vallance, Jefferson E.; Ito, Masataka; Ondr, Jennifer K.; Kurup, Savita; Glass, Donald A.; Patel, Millan S.; Shu, Weiguo; Morrisey, Edward E.; McMahon, Andrew P.; Karsenty, Gerard; Lang, Richard A.

2005-01-01

Macrophages have a critical role in inflammatory and immune responses through their ability to recognize and engulf apoptotic cells1. Here we show that macrophages initiate a cell-death programme in target cells by activating the canonical WNT pathway. We show in mice that macrophage WNT7b is a short-range paracrine signal required for WNT-pathway responses and programmed cell death in the vascular endothelial cells of the temporary hyaloid vessels of the developing eye. These findings indica...

Fibered confocal fluorescence microscopy for imaging apoptotic DNA fragmentation at the single-cell level in vivo

International Nuclear Information System (INIS)

Al-Gubory, Kais H.

2005-01-01

The major characteristic of cell death by apoptosis is the loss of nuclear DNA integrity by endonucleases, resulting in the formation of small DNA fragments. The application of confocal imaging to in vivo monitoring of dynamic cellular events, like apoptosis, within internal organs and tissues has been limited by the accessibility to these sites. Therefore, the aim of the present study was to test the feasibility of fibered confocal fluorescence microscopy (FCFM) to image in situ apoptotic DNA fragmentation in surgically exteriorized sheep corpus luteum in the living animal. Following intra-luteal administration of a fluorescent DNA-staining dye, YO-PRO-1, DNA cleavage within nuclei of apoptotic cells was serially imaged at the single-cell level by FCFM. This imaging technology is sufficiently simple and rapid to allow time series in situ detection and visualization of cells undergoing apoptosis in the intact animal. Combined with endoscope, this approach can be used for minimally invasive detection of fluorescent signals and visualization of cellular events within internal organs and tissues and thereby provides the opportunity to study biological processes in the natural physiological environment of the cell in living animals

The extrinsic and intrinsic apoptotic pathways are involved in manganese toxicity in rat astrocytoma C6 cells.

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Alaimo, Agustina; Gorojod, Roxana M; Kotler, Mónica L

2011-08-01

Manganese (Mn) is a trace element known to be essential for maintaining the proper function and regulation of many biochemical and cellular reactions. However, chronic exposure to high levels of Mn in occupational or environmental settings can lead to its accumulation in the brain resulting in a degenerative brain disorder referred to as Manganism. Astrocytes are the main Mn store in the central nervous system and several lines of evidence implicate these cells as major players in the role of Manganism development. In the present study, we employed rat astrocytoma C6 cells as a sensitive experimental model for investigating molecular mechanisms involved in Mn neurotoxicity. Our results show that C6 cells undergo reactive oxygen species-mediated apoptotic cell death involving caspase-8 and mitochondrial-mediated pathways in response to Mn. Exposed cells exhibit typical apoptotic features, such as chromatin condensation, cell shrinkage, membrane blebbing, caspase-3 activation and caspase-specific cleavage of the endogenous substrate poly (ADP-ribose) polymerase. Participation of the caspase-8 dependent pathway was assessed by increased levels of FasL, caspase-8 activation and Bid cleavage. The involvement of the mitochondrial pathway was demonstrated by the disruption of the mitochondrial membrane potential, the opening of the mitochondrial permeability transition pore, cytochrome c release, caspase-9 activation and the increased mitochondrial levels of the pro-apoptotic Bcl-2 family proteins. In addition, our data also shows for the first time that mitochondrial fragmentation plays a relevant role in Mn-induced apoptosis. Taking together, these findings contribute to a deeper elucidation of the molecular signaling mechanisms underlying Mn-induced apoptosis. Copyright © 2011 Elsevier B.V. All rights reserved.

Activation of the intrinsic-apoptotic pathway in LNCaP prostate cancer cells by genistein- topotecan combination treatments

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Vanessa Hörmann

2013-03-01

Full Text Available ABSTRACTBackground: Prostate cancer is the second most common cancer in American men. The development of alternative preventative and/or treatment options utilizing a combination of phytochemicals and chemotherapeutic drugs could be an attractive alternative compared to conventional carcinoma treatments. Genistein isoflavone is the primary dietary phytochemical found in soy and has demonstrated anti-tumor activities in LNCaP prostate cancer cells. Topotecan Hydrochloride (Hycamtin is an FDA-approved chemotherapy for secondary treatment of lung, ovarian and cervical cancers. The purpose of this study was to detail the potential activation of the intrinsic apoptotic pathway in LNCaP prostate cancer cells through genistein-topotecan combination treatments.Methods: LNCaP cells were cultured in complete RPMI medium in a monolayer (70-80% confluency at 37ºC and 5% CO2. Treatment consisted of single and combination groups of genistein and topotecan for 24 hours. The treated cells were assayed for i growth inhibition through trypan blue exclusion assay and microphotography , ii classification of cellular death through acridine/ ethidium bromide fluorescent staining, and iii activation of the intrinsic apoptotic pathway through Jc-1: mitochondrial membrane potential assay, cytochrome c release and Bcl-2 protein expression.Results: The overall data indicated that genistein-topotecan combination was significantly more efficacious in reducing the prostate carcinoma’s viability compared to the single treatment options. In all treatment groups, cell death occurred primarily through the activation of the intrinsic apoptotic pathway.Conclusion: The combination of topotecan and genistein has the potential to lead to treatment options with equal therapeutic efficiency as traditional chemo- and radiation therapies, but lower cell cytotoxicity and fewer side effects in patients.

Histone deacetylase inhibitors strongly sensitise neuroblastoma cells to TRAIL-induced apoptosis by a caspases-dependent increase of the pro- to anti-apoptotic proteins ratio

International Nuclear Information System (INIS)

Mühlethaler-Mottet, Annick; Flahaut, Marjorie; Bourloud, Katia Balmas; Auderset, Katya; Meier, Roland; Joseph, Jean-Marc; Gross, Nicole

2006-01-01

Neuroblastoma (NB) is the second most common solid childhood tumour, an aggressive disease for which new therapeutic strategies are strongly needed. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in most tumour cells, but not in normal tissues and therefore represents a valuable candidate in apoptosis-inducing therapies. Caspase-8 is silenced in a subset of highly malignant NB cells, which results in full TRAIL resistance. In addition, despite constitutive caspase-8 expression, or its possible restoration by different strategies, NB cells remain weakly sensitive to TRAIL indicating a need to develop strategies to sensitise NB cells to TRAIL. Histone deacetylase inhibitors (HDACIs) are a new class of anti-cancer agent inducing apoptosis or cell cycle arrest in tumour cells with very low toxicity toward normal cells. Although HDACIs were recently shown to increase death induced by TRAIL in weakly TRAIL-sensitive tumour cells, the precise involved sensitisation mechanisms have not been fully identified. NB cell lines were treated with various doses of HDACIs and TRAIL, then cytotoxicity was analysed by MTS/PMS proliferation assays, apoptosis was measured by the Propidium staining method, caspases activity by colorimetric protease assays, and (in)activation of apoptotic proteins by immunoblotting. Sub-toxic doses of HDACIs strongly sensitised caspase-8 positive NB cell lines to TRAIL induced apoptosis in a caspases dependent manner. Combined treatments increased the activation of caspases and Bid, and the inactivation of the anti-apoptotic proteins XIAP, Bcl-x, RIP, and survivin, thereby increasing the pro- to anti-apoptotic protein ratio. It also enhanced the activation of the mitochondrial pathway. Interestingly, the kinetics of caspases activation and inactivation of anti-apoptotic proteins is accelerated by combined treatment with TRAIL and HDACIs compared to TRAIL alone. In contrast, cell surface expression of TRAIL

99mTc rh-Annexin V for imaging apoptotic cells: Clinical experience

International Nuclear Information System (INIS)

Abdel-Dayem, H.M.; Sadek, S.; Heiba, S.; Steinmetz, N.; Cho, J.; Cook, W.; Klein, P.

2002-01-01

Introduction: 99m Tc rh-Annexin V (Apomate, Theseus Imaging Corp., Boston, MA), an investigational nuclear medicine agent for imaging apoptotic and necrotic cell death, is currently in Phase II-III clinical trials. Potential applications being evaluated include identification and localization of acute myocardial infarction, non-invasive assessment of cardiac transplant rejection, and early prediction of cancer chemotherapy response. The purposes of this presentation are: 1) To familiarize attendees with the biological basis of 99m Tc-Annexin V localization, the labeling procedure, biodistribution following I.V. injection, and dosimetric data; 2) In patients with acute myocardial infarction (AMI), dual isotope SPECT using 99m Tc-Annexin V and Thallium-201 was performed within 4 days from onset of AMI and 6 weeks later. It demonstrates the increased uptake of 99m Tc-Annexin V in the recent MI area correlating with the perfusion defect in the Thallium study. 99m Tc-Annexin V disappears in the follow-up scan 6 weeks later indicating that 99m Tc-Annexin V will be a clinically useful agent for determining the size and location of recent AMI and for differentiating AMI from myocardial scar. 3) To demonstrate examples of current applications in oncology for predicting chemo- and radiotherapy response in patients with small and non-small cell lung cancer, Hodgkin's and non-Hodgkin's malignant lymphoma and recurrent, metastatic or inoperable breast carcinoma. Early results show significant correlation with treatment response and patient survival. 4) To demonstrate unusual site of 99m Tc-Annexin V uptake in subdural hematoma and non-lactating breast 4 weeks post partum. In light of the current clinical studies of 99m Tc-Annexin V (Apomate) imaging and the potential approval for clinical use in the future, it is important for practicing nuclear medicine physicians to be aware of the normal distribution, expected patterns of uptake in various pathologic conditions, and unusual

Glycine tomentella Hayata inhibits IL-1β and IL-6 production, inhibits MMP-9 activity, and enhances RAW264.7 macrophage clearance of apoptotic cells

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Sun Yu-Shu

2010-11-01

Full Text Available Abstract Background To assess the effects of Glycine tomentella Hayata (GTH, a traditional herbal medicine for treatment of rheumatic diseases on the expression of the proinflammatory cytokines and on the clearance of apoptotic cells by macrophages. Methods RAW264.7 cells were cultured with lipopolysaccharide (LPS in the presence or absence of ethanol extract of GTH. The expression of proinflammatory cytokines IL-1β, IL-6, and TNF-α, and inducible nitric oxide synthase (iNOS and transglutaminase 2 (TG2 were assayed by reverse transcriptase-polymerase chain reaction (RT-PCR and enzyme-linked immunosorbent assay (ELISA. Matrix metalloproteinase (MMP-2 and MMP-9 were assayed by gelatin zymography. For detecting uptake of apoptotic cells, RAW264.7 cells were cultured with carboxyfluorescein diacetate (CFDA-stained apoptotic cells and assayed by flow cytometry. Results The major components of GTH analyzed by high-performance liquid chromatography (HPLC chromatogram were daidzein (42.5%, epicatechin (28.8%, and naringin (9.4%. GTH treatment inhibited the expression of proinflammatory cytokines IL-1β, IL-6 and MMP-9 but did not affect the expression of TNF-α and iNOS. GTH significantly enhanced the expression of TG2 and the clearance of apoptotic cells by RAW264.7 macrophages. Conclusions GTH inhibits proinflammatory cytokine secretion and MMP-9 activity, enhances apoptotic cell uptake and up-regulates TG2 expression. Our data show that GTH might have beneficial effects on rheumatic diseases.

Anti-apoptotic effects of pan-caspase inhibitor (Z-VAD), SOD or catalase on antimycin A-induced HeLa cell death.

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Han, Yong Hwan; Kim, Suhn Hee; Kim, Sung Zoo; Park, Woo Hyun

2009-01-01

Antimycin A (AMA) is an inhibitor of the electron transport chain in mitochondria. In this study, we investigated the anti-apoptotic effects of pan-caspase inhibitor (Z-VAD), superoxide dismutase (SOD) or catalase on AMA-induced HeLa cell death in relation to the cell cycle. Treatment with Z-VAD, SOD or catalase rescued some HeLa cells from AMA-induced apoptosis, but did not prevent the growth inhibition of HeLa cells by AMA. DNA flow cytometric analysis indicated that treatment with AMA significantly induced an S-phase arrest of the cell cycle at 72 h. Interestingly, Z-VAD, SOD and catalase intensified S-phase arrest in AMA-treated cells. In conclusion, treatment with Z-VAD, SOD or catalase decreased apoptotic levels in AMA-treated cells, which was associated with the enhancement of the S-phase arrest of the cell cycle in these cells.

Classification of Normal and Apoptotic Cells from Fluorescence Microscopy Images Using Generalized Polynomial Chaos and Level Set Function.

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Du, Yuncheng; Budman, Hector M; Duever, Thomas A

2016-06-01

Accurate automated quantitative analysis of living cells based on fluorescence microscopy images can be very useful for fast evaluation of experimental outcomes and cell culture protocols. In this work, an algorithm is developed for fast differentiation of normal and apoptotic viable Chinese hamster ovary (CHO) cells. For effective segmentation of cell images, a stochastic segmentation algorithm is developed by combining a generalized polynomial chaos expansion with a level set function-based segmentation algorithm. This approach provides a probabilistic description of the segmented cellular regions along the boundary, from which it is possible to calculate morphological changes related to apoptosis, i.e., the curvature and length of a cell's boundary. These features are then used as inputs to a support vector machine (SVM) classifier that is trained to distinguish between normal and apoptotic viable states of CHO cell images. The use of morphological features obtained from the stochastic level set segmentation of cell images in combination with the trained SVM classifier is more efficient in terms of differentiation accuracy as compared with the original deterministic level set method.

Lack of a functional VHL gene product sensitizes renal cell carcinoma cells to the apoptotic effects of the protein synthesis inhibitor verrucarin A.

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Woldemichael, Girma M; Turbyville, Thomas J; Vasselli, James R; Linehan, W Marston; McMahon, James B

2012-08-01

Verrucarin A (VA) is a small molecule derived from the fungal plant pathogen Myrothecium verrucaria and was identified as a selective inhibitor of clear cell renal cell carcinoma (CCRCC) cell proliferation in a high-throughput screen of a library of naturally occurring small molecules. CCRCC arises as a result of loss-of-function mutations in the von Hippel-Lindau (VHL) gene. Here we show that VA inhibits protein translation initiation culminating in apoptosis through the extrinsic signaling pathway. Reintroduction of the VHL gene in CCRCC cells afforded resistance to VA's apoptotic effects. This resistance is mediated in part by the formation of stress granules that entrap signaling molecules that initiate the apoptotic signaling cascade. The VHL gene product was found to be a component of stress granules that develop as result of VA treatment. These findings reveal an important role for the VHL gene product in cytotoxic stress response and have important implications for the rational development of VA-related compounds in chemotherapeutic targeting of CCRCC.

The Study of Apoptotic Effect of p-Coumaric Acid on Breast Cancer Cells MCF-7

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M Kolahi

2016-06-01

Full Text Available Introduction: Polyphenolic compounds have anti proliferative and induced apoptotic features on cancer cells. p-Coumaric acid can be abundantly found in fruits, vegetables, plant production and honey. .  Breast cancer is the most frequently diagnosed cancer among women in the world. This study aimed to investigate the effect and mechanism of p- coumaric acid on apoptosis of MCF-7 breast cancer cells. Methods: In order to study appoptic effect of p- coumaric acid, MCF-7 breast cancer cells were treated with different concentrations of p- coumaric acid (10, 37, 70, 150 and 300 mM for 24 h. Cell viability was determined using MTT assay. Apoptosis markers including phosphatidylserine exposure at the outer leaflet of the plasma membrane were measured using flow cytometery for Annexin V affinity. Results: Cell viability of MCF-7 cells was decreased with increasing of p- coumaric acid concentration. Maximal effect of p- coumaric acid was observed in cells that treated with 300 mM for 24h (p< 0.05. Viability assay showed that the IC50 of p- coumaric acid in MCF-7 cells was about 40 mM. p- coumaric acid at dose of 300 mM significantly increased the late apoptotic cells with Annexin V+ and propium iodide (PI+ features after 24 h treatment. Conclusion: The results of this study showed that p- coumaric acid had effective appoptic activity against MCF-7 cells. The results can be helpful in understanding the anticancer mechanism of p- coumaric acid and using it was suggested as an alternative or complementary drug in cancer chemotherapy.

DNA Repair in Human Pluripotent Stem Cells Is Distinct from That in Non-Pluripotent Human Cells

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Luo, Li Z.; Park, Sang-Won; Bates, Steven E.; Zeng, Xianmin; Iverson, Linda E.; O'Connor, Timothy R.

2012-01-01

The potential for human disease treatment using human pluripotent stem cells, including embryonic stem cells and induced pluripotent stem cells (iPSCs), also carries the risk of added genomic instability. Genomic instability is most often linked to DNA repair deficiencies, which indicates that screening/characterization of possible repair deficiencies in pluripotent human stem cells should be a necessary step prior to their clinical and research use. In this study, a comparison of DNA repair pathways in pluripotent cells, as compared to those in non-pluripotent cells, demonstrated that DNA repair capacities of pluripotent cell lines were more heterogeneous than those of differentiated lines examined and were generally greater. Although pluripotent cells had high DNA repair capacities for nucleotide excision repair, we show that ultraviolet radiation at low fluxes induced an apoptotic response in these cells, while differentiated cells lacked response to this stimulus, and note that pluripotent cells had a similar apoptotic response to alkylating agent damage. This sensitivity of pluripotent cells to damage is notable since viable pluripotent cells exhibit less ultraviolet light-induced DNA damage than do differentiated cells that receive the same flux. In addition, the importance of screening pluripotent cells for DNA repair defects was highlighted by an iPSC line that demonstrated a normal spectral karyotype, but showed both microsatellite instability and reduced DNA repair capacities in three out of four DNA repair pathways examined. Together, these results demonstrate a need to evaluate DNA repair capacities in pluripotent cell lines, in order to characterize their genomic stability, prior to their pre-clinical and clinical use. PMID:22412831

Comparative studies of cytotoxic and apoptotic properties of different extracts and the essential oil of Lavandula angustifolia on malignant and normal cells.

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Tayarani-Najaran, Zahra; Amiri, Atefeh; Karimi, Gholamreza; Emami, Seyed Ahmad; Asili, Javad; Mousavi, Seyed Hadi

2014-01-01

Lavender (Lavandula angustifolia Mill.) is a bush-like shrub from Lamiaceae. The herb has been used in alternative medicine for several centuries. In this study, the cytotoxicity and the mechanisms of cell death induced by 3 different extracts of aerial parts and the essential oil of L. angustifolia were compared in normal and cancerous human cells. Malignant (HeLa and MCF-7 cell lines) and nonmalignant (human fibroblasts) cells were incubated with different concentrations of the plant extracts. Cell viability was quantified by MTS assay. Apoptotic cells were determined using propidium iodide staining of DNA fragmentation by flow cytometry (sub-G1 peak). The molecules as apoptotic signal translation, including Bax and cleaved PARP, were identified by Western blot. Ethanol and n-hexane extracts and essential oil exhibited significant cytotoxicity to malignant cells but marginal cytotoxicity to human fibroblasts in vitro and induced a sub-G1 peak in flow cytometry histogram of treated cells compared to the control. Western blot analysis demonstrated that EtOH and n-hexane extracts upregulated Bax expression, also it induced cleavage of PARP in HeLa cells compared to the control. In conclusion, L. angustifolia has cytotoxic and apoptotic effects in HeLa and MCF-7 cell lines, and apoptosis is proposed as the possible mechanism of action.

E-Cigarette Vapor Induces an Apoptotic Response in Human Gingival Epithelial Cells Through the Caspase-3 Pathway.

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Rouabhia, Mahmoud; Park, Hyun Jin; Semlali, Abdelhabib; Zakrzewski, Andrew; Chmielewski, Witold; Chakir, Jamila

2017-06-01

Electronic cigarettes represent an increasingly significant proportion of today's consumable tobacco products. E-cigarettes contain several chemicals which may promote oral diseases. The aim of this study was to investigate the effect of e-cigarette vapor on human gingival epithelial cells. Results show that e-cigarette vapor altered the morphology of cells from small cuboidal form to large undefined shapes. Both single and multiple exposures to e-cigarette vapor led to a bulky morphology with large faint nuclei and an enlarged cytoplasm. E-cigarette vapor also increased L-lactate dehydrogenase (LDH) activity in the targeted cells. This activity was greater with repeated exposures. Furthermore, e-cigarette vapor increased apoptotic/necrotic epithelial cell percentages compared to that observed in the control. Epithelial cell apoptosis was confirmed by TUNEL assay showing that exposure to e-cigarette vapor increased apoptotic cell numbers, particularly after two and three exposures. This negative effect involved the caspase-3 pathway, the activity of which was greater with repeated exposure and which decreased following the use of caspase-3 inhibitor. The adverse effects of e-cigarette vapor on gingival epithelial cells may lead to dysregulated gingival cell function and result in oral disease. J. Cell. Physiol. 232: 1539-1547, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Helicobacter pylori counteracts the apoptotic action of its VacA toxin by injecting the CagA protein into gastric epithelial cells.

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Amanda Oldani

2009-10-01

Full Text Available Infection with Helicobacter pylori is responsible for gastritis and gastroduodenal ulcers but is also a high risk factor for the development of gastric adenocarcinoma and lymphoma. The most pathogenic H. pylori strains (i.e., the so-called type I strains associate the CagA virulence protein with an active VacA cytotoxin but the rationale for this association is unknown. CagA, directly injected by the bacterium into colonized epithelium via a type IV secretion system, leads to cellular morphological, anti-apoptotic and proinflammatory effects responsible in the long-term (years or decades for ulcer and cancer. VacA, via pinocytosis and intracellular trafficking, induces epithelial cell apoptosis and vacuolation. Using human gastric epithelial cells in culture transfected with cDNA encoding for either the wild-type 38 kDa C-terminal signaling domain of CagA or its non-tyrosine-phosphorylatable mutant form, we found that, depending on tyrosine-phosphorylation by host kinases, CagA inhibited VacA-induced apoptosis by two complementary mechanisms. Tyrosine-phosphorylated CagA prevented pinocytosed VacA to reach its target intracellular compartments. Unphosphorylated CagA triggered an anti-apoptotic activity blocking VacA-induced apoptosis at the mitochondrial level without affecting the intracellular trafficking of the toxin. Assaying the level of apoptosis of gastric epithelial cells infected with wild-type CagA(+/VacA(+H. pylori or isogenic mutants lacking of either CagA or VacA, we confirmed the results obtained in cells transfected with the CagA C-ter constructions showing that CagA antagonizes VacA-induced apoptosis. VacA toxin plays a role during H. pylori stomach colonization. However, once bacteria have colonized the gastric niche, the apoptotic action of VacA might be detrimental for the survival of H. pylori adherent to the mucosa. CagA association with VacA is thus a novel, highly ingenious microbial strategy to locally protect its

Membrane microdomain-associated uroplakin IIIa contributes to Src-dependent mechanisms of anti-apoptotic proliferation in human bladder carcinoma cells

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Shigeru Kihira

2012-08-01

Our previous study demonstrated that tyrosine phosphorylation of p145met/β-subunit of hepatocyte growth factor receptor by epidermal growth factor receptor and Src contributes to the anti-apoptotic growth of human bladder carcinoma cell 5637 under serum-starved conditions. Here, we show that some other cell lines of human bladder carcinoma, but not other types of human cancer cells, also exhibit Src-dependent, anti-apoptotic proliferation under serum-starved conditions, and that low-density, detergent-insoluble membrane microdomains (MD serve as a structural platform for signaling events involving p145met, EGFR, and Src. As an MD-associated molecule that may contribute to bladder carcinoma-specific cellular function, we identified uroplakin IIIa (UPIIIa, an urothelium-specific protein. Results obtained so far revealed: 1 UPIIIa undergoes partial proteolysis in serum-starved cells; 2 a specific antibody to the extracellular domain of UPIIIa inhibits the proteolysis of UPIIIa and the activation of Src, and promotes apoptosis in serum-starved cells; and 3 knockdown of UPIIIa by short interfering RNA also promotes apoptosis in serum-starved cells. GM6001, a potent inhibitor of matrix metalloproteinase (MMP, inhibits the proteolysis of UPIIIa and promotes apoptosis in serum-starved cells. Furthermore, serum starvation promotes expression and secretion of the heparin-binding EGF-like growth factor in a manner that depends on the functions of MMP, Src, and UPIIIa. These results highlight a hitherto unknown signaling network involving a subset of MD-associated molecules in the anti-apoptotic mechanisms of human bladder carcinoma cells.

Identification of chosen apoptotic (TIAR and TIA-1) markers expression in thyroid tissues from adolescents with immune and non-immune thyroid diseases

International Nuclear Information System (INIS)

Bossowski, A.; Czarnocka, B.; Lyczkowska, A.; Bardadin, K.; Czerwinska, J.; Moniuszko, A.; Dadan, J.; Bossowska, A.

2010-01-01

The aim of this study was to estimate sodium iodide symporter (NIS) and thyroid peroxidase (TPO) expression in thyrocytes from patients with GD and no-toxic multi nodular goitre (NTMG) in relationship with apoptotic (TIAR and TIA-1) markers. The investigation was performed on thyroid cells isolated from post operation thyroid tissues from 15 patients aged 12-21 years old with GD and 15 cases aged 13-21 years old with NTMG. Detection of NIS and TPO was performed by immunohistochemistry. Analysis of apoptotic markers in thyroid tissues was performed using antibodies to TIAR and TIA-1 by Western Blot and immunohistochemistry. Identification of pro apoptotic TIAR and TIA-1 molecules in the thyroid tissues revealed a higher expression of both proteins in patients with Graves' disease (+++; +, respectively) in comparison to patients with NTNG (+; 0). In addition, TIAR expression was detected in three bands [p50, p42, p38 (kDa)] and TIA-1 in two bands [p22, p17 (kDa)]. using Western Blot test in patients with thyroid autoimmune diseases. In patients with NTNG expression of both apoptotic proteins was lower and identified in single bands: 42 (kDa) for TIAR and 17 (kDa) for TIA-1. The analysis of expression of NIS and TPO in thyroid follicular cells was higher in patients with Graves' disease in compared to their detection in patients with NTMG. In addition, degree of thyroid antigen expression positive correlated with amount of pro apoptotic markers (TIAR, p<0.001; TIA-1, p<0.025 for NIS; TIAR, p<0.012 for TPO). We conclude that elevated expression of NIS and TPO in Graves' disease is associated with higher stimulation and activation of apoptosis in thyroid follicular cells during autoimmune process. (authors)

Apoptotic activity and gene responses in Drosophila melanogaster S2 cells, induced by azadirachtin A.

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Xu, Lin; Li, Sheng; Ran, Xueqin; Liu, Chang; Lin, Rutao; Wang, Jiafu

2016-09-01

Azadirachtin has been used as an antifeedant and growth disruption agent for many insect species. Previous investigations have reported the apoptotic effects of azadirachtin on some insect cells, but the molecular mechanisms are still not clear. This study investigated the underlying molecular mechanisms for the apoptotic effects induced by azadirachtin on Drosophila melanogaster S2 cells in vitro. The results of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay demonstrated that azadirachtin exhibited significant cytotoxicity to S2 cells in a time- and dose-dependent manner. The changes in cellular morphology and the DNA fragmentation demonstrated that azadirachtin induced remarkable apoptosis of S2 cells. Expression levels of 276 genes were found to be significantly changed in S2 cells after exposure to azadirachtin, as detected by Drosophila genome array. Among these genes, calmodulin (CaM) was the most highly upregulated gene. Azadirachtin was further demonstrated to trigger intracellular Ca(2+) release in S2 cells. The genes related to the apoptosis pathway, determined from chip data, were validated by the real-time quantitative polymerase chain reaction method. The results showed that azadirachtin-mediated intracellular Ca(2+) release was the primary event that triggered apoptosis in Drosophila S2 cells through both pathways of the Ca(2+) -CaM and EcR/Usp signalling cascade. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Anti-Apoptotic Signature in Thymic Squamous Cell Carcinomas - Functional Relevance of Anti-Apoptotic BIRC3 Expression in the Thymic Carcinoma Cell Line 1889c.

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Huang, Bei; Belharazem, Djeda; Li, Li; Kneitz, Susanne; Schnabel, Philipp A; Rieker, Ralf J; Körner, Daniel; Nix, Wilfred; Schalke, Berthold; Müller-Hermelink, Hans Konrad; Ott, German; Rosenwald, Andreas; Ströbel, Philipp; Marx, Alexander

2013-01-01

The molecular pathogenesis of thymomas and thymic carcinomas (TCs) is poorly understood and results of adjuvant therapy are unsatisfactory in case of metastatic disease and tumor recurrence. For these clinical settings, novel therapeutic strategies are urgently needed. Recently, limited sequencing efforts revealed that a broad spectrum of genes that play key roles in various common cancers are rarely affected in thymomas and TCs, suggesting that other oncogenic principles might be important. This made us re-analyze historic expression data obtained in a spectrum of thymomas and thymic squamous cell carcinomas (TSCCs) with a custom-made cDNA microarray. By cluster analysis, different anti-apoptotic signatures were detected in type B3 thymoma and TSCC, including overexpression of BIRC3 in TSCCs. This was confirmed by qRT-PCR in the original and an independent validation set of tumors. In contrast to several other cancer cell lines, the BIRC3-positive TSCC cell line, 1889c showed spontaneous apoptosis after BIRC3 knock-down. Targeting apoptosis genes is worth testing as therapeutic principle in TSCC.

Anti-apoptotic signature in thymic squamous cell carcinomas - functional relevance of anti-apoptotic BIRC3 expression in the thymic carcinoma cell line 1889c

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Bei eHuang

2013-12-01

Full Text Available The molecular pathogenesis of thymomas and thymic carcinomas (TCs is poorly understood and results of adjuvant therapy are unsatisfactory in case of metastatic disease and tumor recurrence. For these clinical settings, novel therapeutic strategies are urgently needed. Recently, limited sequencing efforts revealed that a broad spectrum of genes that play key roles in various common cancers are rarely affected in thymomas and thymic carcinomas, suggesting that other oncogenic principles might be important. This made us re-analyze historic expression data obtained in a spectrum of thymomas and thymic squamous cell carcinomas (TSCC with a custom made cDNA microarray. By cluster analysis, different anti-apoptotic signatures were detected in type B3 thymoma and TSCC, including overexpression of BIRC3 in TSCCs. This was confirmed by qRT-PCR in the original and an independent validation set of tumors. In contrast to several other cancer cell lines, the BIRC3-positive TSCC cell line, 1889c showed spontaneous apoptosis after BIRC3 knock-down. Targeting apoptosis genes is worth testing as therapeutic principle in TSCC.

Intrinsic, pro-apoptotic effects of IGFBP-3 on breast cancer cells are reversible: Involvement of PKA, Rho and ceramide.

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Claire M Perks

2011-05-01

Full Text Available We established previously that IGFBP-3 could exert positive or negative effects on cell function depending upon the extracellular matrix composition and by interacting with integrin signalling. To elicit its pro-apoptotic effects IGFBP-3 bound to caveolin-1 and the beta 1 integrin receptor and increased their association culminating in MAPK activation. Disruption of these complexes or blocking the beta 1 integrin receptor reversed these intrinsic actions of IGFBP-3. In this study we have examined the signalling pathway between integrin receptor binding and MAPK activation that mediates the intrinsic, pro-apoptotic actions of IGFBP-3. We found on inhibiting protein kinase A(PKA, Rho associated kinase (ROCK and ceramide, the accentuating effects of IGFBP-3 on apoptotic triggers were reversed, such that IGFBP-3 then conferred cell survival. We established that IGFBP-3 activated Rho, the upstream regulator of ROCK and that beta1 integrin and PKA were upstream of Rho activation, whereas the involvement of ceramide was downstream. The beta 1 integrin, PKA, Rho and ceramide were all upstream of MAPK activation. These data highlight key components involved in the pro-apoptotic effects of IGFBP-3 and that inhibiting them leads to a reversal in the action of IGFBP-3.

RACK1 downregulates levels of the pro-apoptotic protein Fem1b in apoptosis-resistant colon cancer cells.

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Subauste, M Cecilia; Ventura-Holman, Tereza; Du, Liqin; Subauste, Jose S; Chan, Shing-Leng; Yu, Victor C; Maher, Joseph F

2009-12-01

Evasion of apoptosis plays an important role in colon cancer progression. Following loss of the Apc tumor suppressor gene in mice, the gene encoding Fem1b is upregulated early in neoplastic intestinal epithelium. Fem1b is a pro-apoptotic protein that interacts with Fas, TNFR1 and Apaf-1, and increased expression of Fem1b induces apoptosis of cancer cells. Fem1b is a homolog of FEM-1, a protein in Caenorhabditis elegans that is negatively regulated by ubiquitination and proteasomal degradation. To study Fem1b regulation in colon cancer progression, we used apoptotis-sensitive SW480 cells, derived from a primary colon cancer, and their isogenic, apoptosis-resistant counterparts SW620 cells, derived from a subsequent metastatic lesion in the same patient. Treatment with proteasome inhibitor increased Fem1b protein levels in SW620 cells, but not in SW480 cells. In SW620 cells we found that endogenous Fem1b co-immunoprecipitates in complexes with RACK1, a protein known to mediate ubiquitination and proteasomal degradation of other pro-apoptotic proteins and to be upregulated in colon cancer. Full-length Fem1b, or the N-terminal region of Fem1b, associated with RACK1 when co-expressed in HEK293T cells, and RACK1 stimulated ubiquitination of Fem1b. RACK1 overexpression in SW620 cells led to downregulation of Fem1b protein levels. Conversely, downregulation of RACK1 led to upregulation of Fem1b protein levels, associated with induction of apoptosis, and this apoptosis was inhibited by blocking Fem1b protein upregulation. In conclusion, RACK1 downregulates levels of the pro-apoptotic protein Fem1b in metastatic, apoptosis-resistant colon cancer cells, which may promote apoptosis-resistance during progression of colon cancer.

Cobalt iron oxide nanoparticles induce cytotoxicity and regulate the apoptotic genes through ROS in human liver cells (HepG2).

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Ahamed, Maqusood; Akhtar, Mohd Javed; Khan, M A Majeed; Alhadlaq, Hisham A; Alshamsan, Aws

2016-12-01

Cobalt iron oxide (CoFe 2 O 4 ) nanoparticles (CIO NPs) have been one of the most widely explored magnetic NPs because of their excellent chemical stability, mechanical hardness and heat generating potential. However, there is limited information concerning the interaction of CIO NPs with biological systems. In this study, we investigated the reactive oxygen species (ROS) mediated cytotoxicity and apoptotic response of CIO NPs in human liver cells (HepG2). Diameter of crystalline CIO NPs was found to be 23nm with a band gap of 1.97eV. CIO NPs induced cell viability reduction and membrane damage, and degree of induction was dose- and time-dependent. CIO NPs were also found to induce oxidative stress revealed by induction of ROS, depletion of glutathione and lower activity of superoxide dismutase enzyme. Real-time PCR data has shown that mRNA level of tumor suppressor gene p53 and apoptotic genes (bax, CASP3 and CASP9) were higher, while the expression level of anti-apoptotic gene bcl-2 was lower in cells following exposure to CIO NPs. Activity of caspase-3 and caspase-9 enzymes was also higher in CIO NPs exposed cells. Furthermore, co-exposure of N-acetyl-cysteine (ROS scavenger) efficiently abrogated the modulation of apoptotic genes along with the prevention of cytotoxicity caused by CIO NPs. Overall, we observed that CIO NPs induced cytotoxicity and apoptosis in HepG2 cells through ROS via p53 pathway. This study suggests that toxicity mechanisms of CIO NPs should be further investigated in animal models. Copyright © 2016 Elsevier B.V. All rights reserved.

Exposure to apoptotic activated CD4+ T cells induces maturation and APOBEC3G-mediated inhibition of HIV-1 infection in dendritic cells.

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Venkatramanan Mohanram

Full Text Available Dendritic cells (DCs are activated by signaling via pathogen-specific receptors or exposure to inflammatory mediators. Here we show that co-culturing DCs with apoptotic HIV-infected activated CD4(+ T cells (ApoInf or apoptotic uninfected activated CD4(+ T cells (ApoAct induced expression of co-stimulatory molecules and cytokine release. In addition, we measured a reduced HIV infection rate in DCs after co-culture with ApoAct. A prerequisite for reduced HIV infection in DCs was activation of CD4(+ T cells before apoptosis induction. DCs exposed to ApoAct or ApoInf secreted MIP-1α, MIP-1β, MCP-1, and TNF-α; this effect was retained in the presence of exogenous HIV. The ApoAct-mediated induction of co-stimulatory CD86 molecules and reduction of HIV infection in DCs were partially abrogated after blocking TNF-α using monoclonal antibodies. APOBEC3G expression in DCs was increased in co-cultures of DCs and ApoAct but not by apoptotic resting CD4(+ T cells (ApoRest. Silencing of APOBEC3G in DC abrogated the HIV inhibitory effect mediated by ApoAct. Sequence analyses of an env region revealed significant induction of G-to-A hypermutations in the context of GG or GA dinucleotides in DNA isolated from DCs exposed to HIV and ApoAct. Thus, ApoAct-mediated DC maturation resulted in induction of APOBEC3G that was important for inhibition of HIV-infection in DCs. These findings underscore the complexity of differential DC responses evoked upon interaction with resting as compared with activated dying cells during HIV infection.

Uptake of apoptotic leukocytes by synovial lining macrophages inhibits immune complex-mediated arthritis.

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van Lent, P L; Licht, R; Dijkman, H; Holthuysen, A E; Berden, J H; van den Berg, W B

2001-11-01

Previously we have shown that synovial lining macrophages (SLMs) determine the onset of experimental immune complex-mediated arthritis (ICA). During joint inflammation, many leukocytes undergo apoptosis, and removal of leukocytes by SLMs may regulate resolution of inflammation. In this study we investigated binding and uptake of apoptotic leukocytes by SLMs and its impact on the onset of murine experimental arthritis. We used an in vitro model to evaluate phagocytosis of apoptotic cells on chemotaxis. Phagocytosis of apoptotic thymocytes resulted in a significant decrease (58%) of chemotactic activity for polymorphonuclear neutrophils (PMNs). If apoptotic cells were injected directly into a normal murine knee joint, SLMs resulted in a prominent uptake of cells. After ICA induction, electron micrographs showed that apoptotic leukocytes were evidently present in SLMs on days 1 and 2. Injection of apoptotic leukocytes into the knee joint 1 h before induction of ICA significantly inhibited PMN infiltration into the knee joint at 24 h (61% decrease). This study indicates that uptake of apoptotic leukocytes by SLM reduces chemotactic activity and inhibits the onset of experimental arthritis. These findings indicate an important mechanism in the resolution of joint inflammation.

Eclalbasaponin II induces autophagic and apoptotic cell death in human ovarian cancer cells

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Yoon Jin Cho

2016-09-01

Full Text Available Triterpenoids echinocystic acid and its glycosides, isolated from several Eclipta prostrata, have been reported to possess various biological activities such as anti-inflammatory, anti-bacterial, and anti-diabetic activity. However, the cytotoxicity of the triterpenoids in human cancer cells and their molecular mechanism of action are poorly understood. In the present study, we found that eclalbasaponin II with one glucose moiety has potent cytotoxicity in three ovarian cancer cells and two endometrial cancer cells compared to an aglycone echinocystic acid and eclalbasaponin I with two glucose moiety. Eclalbasaponin II treatment dose-dependently increased sub G1 population. Annexin V staining revealed that eclalbasaponin II induced apoptosis in SKOV3 and A2780 ovarian cancer cells. In addition, eclalbasaponin II-induced cell death was associated with characteristics of autophagy; an increase in acidic vesicular organelle content and elevation of the levels of LC3-II. Interestingly, autophagy inhibitor BaF1 suppressed the eclalbasaponin II-induced apoptosis. Moreover, eclalbasaponin II activated JNK and p38 signaling and inhibited the mTOR signaling. We further demonstrated that pre-treatment with a JNK and p38 inhibitor and mTOR activator attenuated the eclalbasaponin II-induced autophagy. This suggests that eclalbasaponin II induces apoptotic and autophagic cell death through the regulation of JNK, p38, and mTOR signaling in human ovarian cancer cells.

Distinct apoptotic blocks mediate resistance to panHER inhibitors in HER2+ breast cancer cells.

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Karakas, Bahriye; Ozmay, Yeliz; Basaga, Huveyda; Gul, Ozgur; Kutuk, Ozgur

2018-05-04

Despite the development of novel targeted therapies, de novo or acquired chemoresistance remains a significant factor for treatment failure in breast cancer therapeutics. Neratinib and dacomitinib are irreversible panHER inhibitors, which block their autophosphorylation and downstream signaling. Moreover, neratinib and dacomitinib have been shown to activate cell death in HER2-overexpressing cell lines. Here we showed that increased MCL1 and decreased BIM and PUMA mediated resistance to neratinib in ZR-75-30 and SKBR3 cells while increased BCL-XL and BCL-2 and decreased BIM and PUMA promoted neratinib resistance in BT474 cells. Cells were also cross-resistant to dacomitinib. BH3 profiles of HER2+ breast cancer cells efficiently predicted antiapoptotic protein dependence and development of resistance to panHER inhibitors. Reactivation of ERK1/2 was primarily responsible for acquired resistance in SKBR3 and ZR-75-30 cells. Adding specific ERK1/2 inhibitor SCH772984 to neratinib or dacomitinib led to increased apoptotic response in neratinib-resistant SKBR3 and ZR-75-30 cells, but we did not detect a similar response in neratinib-resistant BT474 cells. Accordingly, suppression of BCL-2/BCL-XL by ABT-737 was required in addition to ERK1/2 inhibition for neratinib- or dacomitinib-induced apoptosis in neratinib-resistant BT474 cells. Our results showed that different mitochondrial apoptotic blocks mediated acquired panHER inhibitor resistance in HER2+ breast cancer cell lines as well as highlighted the potential of BH3 profiling assay in prediction of panHER inhibitor resistance in breast cancer cells. Copyright © 2018 Elsevier B.V. All rights reserved.

Expression Profile of Apoptotic Mediators and Proliferative Markers in Oral Squamous Cell Carcinoma

International Nuclear Information System (INIS)

Ahmed, M.M.

2009-01-01

Oral squamous cell carcinoma (OSCC) represents a major health problem worldwide. It is therefore essential to develop a deeper understanding of its biology. Beside the recent hypothesis of cancer stem cells, the consideration of its cell death and cell proliferation has emerged as important diagnostic and prognostic tools. Purpose of the Study: Detection of the proportion of cell loss monitored by apoptosis-related genes, p53, p21 and Bcl2, and their relationship to the pathological proliferation parameter, PCNA in OSCC. Furthermore, discussion of the hypothesis of cancer stem cell biology in OSCC would be anticipated. Material and Methods: Archival 35 tissue embedded paraffin blocks, that were previously diagnosed as well to moderately differentiated OSCC, were immunohistochemically stained using a panel of antibodies including apoptotic mediators, p53, p21, Bcl2, and proliferation marker, PCNA. Immuno expression was scored using a semiquantitative scale and statistically analyzed. Results: The clinico-pathological data revealed that mean age was 46.9±8.2 and the tongue was the most affected site, followed by the palate then the floor of the mouth. There was no significant difference between metastasizing and non-metastasizing patients regarding age or gender (p=0.174, 0.404, respectively). On the other hand, variable profile patterns of the investigated indicators existed, where PCNA positively immunostaining cells was 100% while P21 recorded the higher percentage of negatively immunoreactive cells (42.9%). A common trait for the studied cell cycle indicators was that the basal and supra basal epithelial cells as well as the peripheral cells of the invading nests were the harbor of immunoreactivity. Meanwhile, Pca immuno positivity was revealed in all epithelial layers plus stromal cells. Conclusions: Assessment of the studied cell cycle regulators may be valuable to judge tumorigenesis of Osac. Furthermore, deregulation of cell cycle control might aid in the

Tuberin and PRAS40 are anti-apoptotic gatekeepers during early human amniotic fluid stem-cell differentiation.

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Fuchs, Christiane; Rosner, Margit; Dolznig, Helmut; Mikula, Mario; Kramer, Nina; Hengstschläger, Markus

2012-03-01

Embryoid bodies (EBs) are three-dimensional multicellular aggregates allowing the in vitro investigation of stem-cell differentiation processes mimicking early embryogenesis. Human amniotic fluid stem (AFS) cells harbor high proliferation potential, do not raise the ethical issues of embryonic stem cells, have a lower risk for tumor development, do not need exogenic induction of pluripotency and are chromosomal stable. Starting from a single human AFS cell, EBs can be formed accompanied by the differentiation into cells of all three embryonic germ layers. Here, we report that siRNA-mediated knockdown of the endogenous tuberous sclerosis complex-2 (TSC2) gene product tuberin or of proline-rich Akt substrate of 40 kDa (PRAS40), the two major negative regulators of mammalian target of rapamycin (mTOR), leads to massive apoptotic cell death during EB development of human AFS cells without affecting the endodermal, mesodermal and ectodermal cell differentiation spectrum. Co-knockdown of endogenous mTOR demonstrated these effects to be mTOR-dependent. Our findings prove this enzyme cascade to be an essential anti-apoptotic gatekeeper of stem-cell differentiation during EB formation. These data allow new insights into the regulation of early stem-cell maintenance and differentiation and identify a new role of the tumor suppressor tuberin and the oncogenic protein PRAS40 with the relevance for a more detailed understanding of the pathogenesis of diseases associated with altered activities of these gene products.

Anti-apoptotic BFL-1 is the major effector in activation-induced human mast cell survival.

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Maria Ekoff

Full Text Available Mast cells are best known for their role in allergic reactions, where aggregation of FcεRI leads to the release of mast cell mediators causing allergic symptoms. The activation also induces a survival program in the cells, i.e., activation-induced mast cell survival. The aim of the present study was to investigate how the activation-induced survival is mediated. Cord blood-derived mast cells and the mast cell line LAD-2 were activated through FcεRI crosslinking, with or without addition of chemicals that inhibit the activity or expression of selected Bcl-2 family members (ABT-737; roscovitine. Cell viability was assessed using staining and flow cytometry. The expression and function of Bcl-2 family members BFL-1 and MCL-1 were investigated using real-time quantitative PCR and siRNA treatment. The mast cell expression of Bfl-1 was investigated in skin biopsies. FcεRI crosslinking promotes activation-induced survival of human mast cells and this is associated with an upregulation of the anti-apoptotic Bcl-2 family member Bfl-1. ABT-737 alone or in combination with roscovitine decreases viability of human mast cells although activation-induced survival is sustained, indicating a minor role for Bcl-X(L, Bcl-2, Bcl-w and Mcl-1. Reducing BFL-1 but not MCL-1 levels by siRNA inhibited activation-induced mast cell survival. We also demonstrate that mast cell expression of Bfl-1 is elevated in birch-pollen-provocated skin and in lesions of atopic dermatitis and psoriasis patients. Taken together, our results highlight Bfl-1 as a major effector in activation-induced human mast cell survival.

Parallel single-cell analysis of active caspase-3/7 in apoptotic and non-apoptotic cells

Czech Academy of Sciences Publication Activity Database

Ledvina, Vojtěch; Janečková, Eva; Matalová, Eva; Klepárník, Karel

2017-01-01

Roč. 409, č. 1 (2017), s. 269-274 ISSN 1618-2642 R&D Projects: GA ČR(CZ) GA14-28254S Institutional support: RVO:68081715 ; RVO:67985904 Keywords : single-cell analysis * bioluminescence * apoptosis * caspase-3/7 Subject RIV: CB - Analytical Chemistry , Separation; EB - Genetics ; Molecular Biology (UZFG-Y) OBOR OECD: Analytical chemistry ; Developmental biology (UZFG-Y) Impact factor: 3.431, year: 2016

Parallel single-cell analysis of active caspase-3/7 in apoptotic and non-apoptotic cells

Czech Academy of Sciences Publication Activity Database

Ledvina, Vojtěch; Janečková, Eva; Matalová, Eva; Klepárník, Karel

2017-01-01

Roč. 409, č. 1 (2017), s. 269-274 ISSN 1618-2642 R&D Projects: GA ČR(CZ) GA14-28254S Institutional support: RVO:68081715 ; RVO:67985904 Keywords : single-cell analysis * bioluminescence * apoptosis * caspase-3/7 Subject RIV: CB - Analytical Chemistry, Separation; EB - Genetics ; Molecular Biology (UZFG-Y) OBOR OECD: Analytical chemistry; Developmental biology (UZFG-Y) Impact factor: 3.431, year: 2016

Apoptotic induction of skin cancer cell death by plant extracts.

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Thuncharoen, Walairat; Chulasiri, Malin; Nilwarangkoon, Sirinun; Nakamura, Yukio; Watanapokasin, Ramida

2013-01-01

The aim of the present study was to investigate the effects of plant extracts on cancer apoptotic induction. Human epidermoid carcinoma A431 cell line, obtained from the American Type Culture Collection (ATCC, Manassas, VA), was maintained in Dulbecco's Modified Eagle Medium (DMEM) supplemented with 10% fetal bovine serum (FBS) at 37 degrees C, 5% carbon dioxide (CO2). Plant extract solutions were obtained from S & J international enterprises public company limited. These plant extracts include 50% hydroglycol extracts from Etlingera elatior (Jack) R.M.Smith (torch ginger; EE), Rosa damascene (damask rose; DR) and Rafflesia kerrii Meijer (bua phut; RM). The cell viability, time and dose dependency were determined by MTT (3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay. A431 cells were treated with the plant extracts and stained with Hoechst 33342 fluorescent staining dye. Cell viability was demonstrated by the inhibitory concentration 50% (IC50). The anti-proliferative effects were shown to be dependent on time and dose. Typical characteristics of apoptosis which are cell morphological changes and chromatin condensation were clearly observed. The plant extracts was shown to be effective for anti-proliferation and induction of apoptosis cell death in skin cancer cells. Therefore, mechanisms underlying the cell death and its potential use for treatment of skin cancer will be further studied.

Investigation of non-thermal plasma effects on lung cancer cells within 3D collagen matrices

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Karki, Surya B.; Thapa Gupta, Tripti; Yildirim-Ayan, Eda; Eisenmann, Kathryn M.; Ayan, Halim

2017-08-01

Recent breakthroughs in plasma medicine have identified a potential application for the non-thermal plasma in cancer therapy. Most studies on the effects of non-thermal plasma on cancer cells have used traditional two-dimensional (2D) monolayer cell culture. However, very few studies are conducted employing non-thermal plasma in animal models. Two dimensional models do not fully mimic the three-dimensional (3D) tumor microenvironment and animal models are expensive and time-consuming. Therefore, we used 3D collagen matrices that closely resemble the native geometry of cancer tissues and provide more physiologically relevant results than 2D models, while providing a more cost effective and efficient precursor to animal studies. We previously demonstrated a role for non-thermal plasma application in promoting apoptotic cell death and reducing the viability of A549 lung adenocarcinoma epithelial cells cultured upon 2D matrices. In this study, we wished to determine the efficacy of non-thermal plasma application in driving apoptotic cell death of A549 lung cancer cells encapsulated within a 3D collagen matrix. The percentage of apoptosis increased as treatment time increased and was time dependent. In addition, the anti-viability effect of plasma was demonstrated. Twenty-four hours post-plasma treatment, 38% and 99% of cell death occurred with shortest (15 s) and longest treatment time (120 s) respectively at the plasma-treated region. We found that plasma has a greater effect on the viability of A549 lung cancer cells on the superficial surface of 3D matrices and has diminishing effects as it penetrates the 3D matrix. We also identified the nitrogen and oxygen species generated by plasma and characterized their penetration in vertical and lateral directions within the 3D matrix from the center of the plasma-treated region. Therefore, the utility of non-thermal dielectric barrier discharge plasma in driving apoptosis and reducing the viability of lung cancer cells

Investigation of non-thermal plasma effects on lung cancer cells within 3D collagen matrices

International Nuclear Information System (INIS)

Karki, Surya B; Gupta, Tripti Thapa; Yildirim-Ayan, Eda; Ayan, Halim; Eisenmann, Kathryn M

2017-01-01

Recent breakthroughs in plasma medicine have identified a potential application for the non-thermal plasma in cancer therapy. Most studies on the effects of non-thermal plasma on cancer cells have used traditional two-dimensional (2D) monolayer cell culture. However, very few studies are conducted employing non-thermal plasma in animal models. Two dimensional models do not fully mimic the three-dimensional (3D) tumor microenvironment and animal models are expensive and time-consuming. Therefore, we used 3D collagen matrices that closely resemble the native geometry of cancer tissues and provide more physiologically relevant results than 2D models, while providing a more cost effective and efficient precursor to animal studies. We previously demonstrated a role for non-thermal plasma application in promoting apoptotic cell death and reducing the viability of A549 lung adenocarcinoma epithelial cells cultured upon 2D matrices. In this study, we wished to determine the efficacy of non-thermal plasma application in driving apoptotic cell death of A549 lung cancer cells encapsulated within a 3D collagen matrix. The percentage of apoptosis increased as treatment time increased and was time dependent. In addition, the anti-viability effect of plasma was demonstrated. Twenty-four hours post-plasma treatment, 38% and 99% of cell death occurred with shortest (15 s) and longest treatment time (120 s) respectively at the plasma-treated region. We found that plasma has a greater effect on the viability of A549 lung cancer cells on the superficial surface of 3D matrices and has diminishing effects as it penetrates the 3D matrix. We also identified the nitrogen and oxygen species generated by plasma and characterized their penetration in vertical and lateral directions within the 3D matrix from the center of the plasma-treated region. Therefore, the utility of non-thermal dielectric barrier discharge plasma in driving apoptosis and reducing the viability of lung cancer cells

Hypoxia-response plasmid vector producing bcl-2 shRNA enhances the apoptotic cell death of mouse rectum carcinoma.

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Fujioka, Takashi; Matsunaga, Naoya; Okazaki, Hiroyuki; Koyanagi, Satoru; Ohdo, Shigehiro

2010-01-01

Hypoxia-induced gene expression frequently occurs in malignant solid tumors because they often have hypoxic areas in which circulation is compromised due to structurally disorganized blood vessels. Hypoxia-response elements (HREs) are responsible for activating gene transcription in response to hypoxia. In this study, we constructed a hypoxia-response plasmid vector producing short hairpin RNA (shRNA) against B-cell leukemia/lymphoma-2 (bcl-2), an anti-apoptotic factor. The hypoxia-response promoter was made by inserting tandem repeats of HREs upstream of cytomegalovirus (CMV) promoter (HRE-CMV). HRE-CMV shbcl-2 vector consisted of bcl-2 shRNA under the control of HRE-CMV promoter. In hypoxic mouse rectum carcinoma cells (colon-26), the production of bcl-2 shRNA driven by HRE-CMV promoter was approximately 2-fold greater than that driven by CMV promoter. A single intratumoral (i.t.) injection of 40 microg HRE-CMV shbcl-2 to colon-26 tumor-bearing mice caused apoptotic cell death, and repetitive treatment with HRE-CMV shbcl-2 (40 microg/mouse, i.t.) also significantly suppressed the growth of colon-26 tumor cells implanted in mice. Apoptotic and anti-tumor effects were not observed in tumor-bearing mice treated with CMV shbcl-2. These results reveal the ability of HRE-CMV shbcl-2 vector to suppress the expression of bcl-2 in hypoxic tumor cells and suggest the usefulness of our constructed hypoxia-response plasmid vector to treat malignant tumors. [Supplementary Figures: available only at http://dx.doi.org/10.1254/jphs.10054FP].

Calcein+/PI- as an early apoptotic feature in Leishmania.

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Louise Basmaciyan

Full Text Available Although leishmaniases are responsible for high morbidity and mortality all over the world, no really satisfying treatment exists. Furthermore, the corresponding parasite Leishmania undergoes a very characteristic form of programmed cell death. Indeed, different stimuli can induce morphological and biochemical apoptotic-like features. However, the key proteins involved in mammal apoptosis, such as caspases and death receptors, are not encoded in the genome of this parasite. Currently, little is known about Leishmania apoptosis, notably owing to the lack of specific tools for programmed cell death analysis in these parasites. Furthermore, there is a need for a better understanding of Leishmania programmed cell death in order (i to better understand the role of apoptosis in unicellular organisms, (ii to better understand apoptosis in general through the study of an ancestral eukaryote, and (iii to identify new therapeutic targets against leishmaniases. To advance understanding of apoptosis in Leishmania, in this study we developed a new tool based on the quantification of calcein and propidium iodide by flow cytometry. This double labeling can be employed to distinguish early apoptosis, late apoptosis and necrosis in Leishmania live cells with a very simple and rapid assay. This paper should, therefore, be of interest for people working on Leishmania and related parasites.

Calcein+/PI- as an early apoptotic feature in Leishmania.

Science.gov (United States)

Basmaciyan, Louise; Azas, Nadine; Casanova, Magali

2017-01-01

Although leishmaniases are responsible for high morbidity and mortality all over the world, no really satisfying treatment exists. Furthermore, the corresponding parasite Leishmania undergoes a very characteristic form of programmed cell death. Indeed, different stimuli can induce morphological and biochemical apoptotic-like features. However, the key proteins involved in mammal apoptosis, such as caspases and death receptors, are not encoded in the genome of this parasite. Currently, little is known about Leishmania apoptosis, notably owing to the lack of specific tools for programmed cell death analysis in these parasites. Furthermore, there is a need for a better understanding of Leishmania programmed cell death in order (i) to better understand the role of apoptosis in unicellular organisms, (ii) to better understand apoptosis in general through the study of an ancestral eukaryote, and (iii) to identify new therapeutic targets against leishmaniases. To advance understanding of apoptosis in Leishmania, in this study we developed a new tool based on the quantification of calcein and propidium iodide by flow cytometry. This double labeling can be employed to distinguish early apoptosis, late apoptosis and necrosis in Leishmania live cells with a very simple and rapid assay. This paper should, therefore, be of interest for people working on Leishmania and related parasites.

Extrinsic and Intrinsic Apoptotic Responses Induced by Shiitake Culinary-Medicinal Mushroom Lentinus edodes (Agaricomycetes) Aqueous Extract against a Larynx Carcinoma Cell Line.

Science.gov (United States)

Finimundy, Tiane C; Scola, Gustavo; Scariot, Fernando J; Dillon, Aldo J P; Moura, Sidnei; Echeverrigaray, Sérgio; Henriques, João Pegas; Roesch-Ely, Mariana

2018-01-01

Cumulative evidence from research studies has shown that the shiitake culinary-medicinal mushroom, Lentinus edodes, is an excellent source of natural antitumor agents and is capable of inhibiting cancer cell growth. However, the cell signaling pathway that leads tumor cells to apoptosis is not well understood because many chemical compounds may be acting. This study investigated the chemopreventive effects of an L. edodes aqueous extract on human HEp-2 epithelial larynx carcinoma cells and normal human MRC-5 lung fibroblasts by identifying proliferative and apoptotic pathways. The chemical characterization of the dry powder was assessed by high-performance liquid chromatography. Antiproliferative and proapoptotic effects induced by the extract were evaluated by assessing proliferative markers, cell sorting through flow cytometry, and expression levels of apoptotic proteins with Western blotting. The results suggest that inhibition of cell proliferation was more prominent in HEp-2 than in MRC-5 cells. Cell death analysis showed the appearance of cell populations in the sub-G1 phase, with late apoptotic signal increased in a dose-dependent manner. In addition, the aqueous extract induced depolarization of mitochondria, activating the generation of intracellular reactive oxygen species in HEp-2 cells. These observations suggest that L. edodes extract may exert a chemopreventive effect, regulating mitotic induction of apoptogenic signals. These findings highlight the mushroom's pharmacological potential in cancer treatment.

[Cell-penetrating chimeric apoptotic peptide AVPI-LMWP/DNA co-delivery system for cancer therapy].

Science.gov (United States)

Tan, Jiao; Wang, Ya-Ping; Wang, Hui-Xin; Liang, Jian-Ming; Zhang, Meng; Sun, Xun; Huang, Yong-Zhuo

2014-12-01

To develop a cell-penetrating chimeric apoptotic peptide AVPI-LMWP/DNA co-delivery system for cancer therapy, we prepared the AVPI-LMWP/pTRAIL self-assembled complexes containing a therapeutic combination of peptide drug AVPI and DNA drug TRAIL. The chimeric apoptotic peptide AVPI-LMWP was synthesized using the standard solid-phase synthesis. The cationic AVPI-LMWP could condense pTRAIL by electrostatic interaction. The physical-chemical properties of the AVPI-LMWP/pTRAIL complexes were characterized. The cellular uptake efficiency and the inhibitory activity of the AVPI-LMWP/pTRAIL complexes on tumor cell were also performed. The results showed that the AVPI-LMWP/pTRAIL complexes were successfully prepared by co-incubation. With the increase of mass ratio (AVPI-LMWP/DNA), the particle size was decreased and the zeta potential had few change. Agarose gel electrophoresis showed that AVPI-LMWP could fully bind and condense pTRAIL at a mass ratio above 15:1. Cellular uptake efficiency was improved along with the increased ratio of W(AVPI-LMWP)/WpTRAIL. The in vitro cytotoxicity experiments demonstrated that the AVPI-LMWP/pTRAIL (W:W = 20:1) complexes was significantly more effective than the pTRAIL, AVPI-LMWP alone or LMWP/pTRAIL complexes on inhibition of HeLa cell growth. Our studies indicated that the AVPI-LMWP/pTRAIL co-delivery system could deliver plasmid into HeLa cell and induce tumor cell apoptosis efficiently, which showed its potential in cancer therapy using combination of apoptoic peptide and gene drugs.

The anti-apoptotic effect of fluid mechanics preconditioning by cells membrane and mitochondria in rats brain microvascular endothelial cells.

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Tian, Shan; Zhu, Fengping; Hu, Ruiping; Tian, Song; Chen, Xingxing; Lou, Dan; Cao, Bing; Chen, Qiulei; Li, Bai; Li, Fang; Bai, Yulong; Wu, Yi; Zhu, Yulian

2018-01-01

Exercise preconditioning is a simple and effective way to prevent ischemia. This paper further provided the mechanism in hemodynamic aspects at the cellular level. To study the anti-apoptotic effects of fluid mechanics preconditioning, Cultured rats brain microvascular endothelial cells were given fluid intervention in a parallel plate flow chamber before oxygen glucose deprivation. It showed that fluid mechanics preconditioning could inhibit the apoptosis of endothelial cells, and this process might be mediated by the shear stress activation of Tie-2 on cells membrane surface and Bcl-2 on the mitochondria surface. Copyright © 2017 Elsevier B.V. All rights reserved.

Lithium attenuates lead induced toxicity on mouse non-adherent bone marrow cells.

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Banijamali, Mahsan; Rabbani-Chadegani, Azra; Shahhoseini, Maryam

2016-07-01

Lead is a poisonous heavy metal that occurs in all parts of environment and causes serious health problems in humans. The aim of the present study was to investigate the possible protective effect of lithium against lead nitrate induced toxicity in non-adherent bone marrow stem cells. Trypan blue and MTT assays represented that exposure of the cells to different concentrations of lead nitrate decreased viability in a dose dependent manner, whereas, pretreatment of the cells with lithium protected the cells against lead toxicity. Lead reduced the number and differentiation status of bone marrow-derived precursors when cultured in the presence of colony stimulating factor (CSF), while the effect was attenuated by lithium. The cells treated with lead nitrate exhibited cell shrinkage, DNA fragmentation, anion superoxide production, but lithium prevented lead action. Moreover, apoptotic indexes such as PARP cleavage and release of HMGB1 induced by lead, were protected by lithium, suggesting anti-apoptotic effect of lithium. Immunoblot analysis of histone H3K9 acetylation indicated that lithium overcame lead effect on acetylation. In conclusion, lithium efficiently reduces lead toxicity suggesting new insight into lithium action which may contribute to increased cell survival. It also provides a potentially new therapeutic strategy for lithium and a cost-effective approach to minimize destructive effects of lead on bone marrow stem cells. Copyright © 2016 Elsevier GmbH. All rights reserved.

The Apoptotic Effects of the P300 Activator on Breast Cancer and Lung Fibroblast Cell Lines

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Mohammad Reza Salahshoor

2013-10-01

Full Text Available Background: P300 is an enzyme that acetylates histones during stress. It alsoacetylates several non-histone proteins, including P53 which is the most important tumorsuppressor gene. P53 plays an important role in the apoptosis of tumor cells. Hereby,this study describes the potency of cholera toxin B subunit as a P300 activator to induceapoptosis in a breast cancer cell line (MCF-7 and a lung fibroblast cell line (MRC-5as a non-tumorigenic control sample. Methods: MCF-7 and MRC-5 were cultured in RPMI-1640 and treated with orwithout cholera toxin B subunit at the concentration of 85.43 μmol/L, based on the half-maximal inhibitory concentration index at different times (24, 48 and 72 h. Thepercentage of apoptotic cells was measured by flow cytometry. Real-time quantitativeRT-PCR was performed to estimate the mRNA expression of P300 in MCF-7 and MRC-5 with cholera toxin B subunit at different times. We used the ELISA and Bradford proteintechniques to detect levels of total and acetylated P53 protein generated in MCF-7 andMRC-5. Results: Our findings indicated that the cholera toxin B subunit effectively andsignificantly induced more apoptosis in MCF-7 compared to MRC-5. We showed thatexpression of P300 up-regulated by increasing the time of the cholera toxin B subunittreatment in MCF-7 but not in MRC-5. In addition, the acetylated and total P53protein levels increased more in MCF-7 cells than in MRC-5 cells.Conclusion: Cholera toxin B subunit induced significant cell death in MCF-7, butit could be well tolerated in MRC-5. Therefore, cholera toxin B subunit can besuggested as an anti-cancer agent.

Anti-Apoptotic Signature in Thymic Squamous Cell Carcinomas – Functional Relevance of Anti-Apoptotic BIRC3 Expression in the Thymic Carcinoma Cell Line 1889c

Science.gov (United States)

Huang, Bei; Belharazem, Djeda; Li, Li; Kneitz, Susanne; Schnabel, Philipp A.; Rieker, Ralf J.; Körner, Daniel; Nix, Wilfred; Schalke, Berthold; Müller-Hermelink, Hans Konrad; Ott, German; Rosenwald, Andreas; Ströbel, Philipp; Marx, Alexander

2013-01-01

The molecular pathogenesis of thymomas and thymic carcinomas (TCs) is poorly understood and results of adjuvant therapy are unsatisfactory in case of metastatic disease and tumor recurrence. For these clinical settings, novel therapeutic strategies are urgently needed. Recently, limited sequencing efforts revealed that a broad spectrum of genes that play key roles in various common cancers are rarely affected in thymomas and TCs, suggesting that other oncogenic principles might be important. This made us re-analyze historic expression data obtained in a spectrum of thymomas and thymic squamous cell carcinomas (TSCCs) with a custom-made cDNA microarray. By cluster analysis, different anti-apoptotic signatures were detected in type B3 thymoma and TSCC, including overexpression of BIRC3 in TSCCs. This was confirmed by qRT-PCR in the original and an independent validation set of tumors. In contrast to several other cancer cell lines, the BIRC3-positive TSCC cell line, 1889c showed spontaneous apoptosis after BIRC3 knock-down. Targeting apoptosis genes is worth testing as therapeutic principle in TSCC. PMID:24427739

Lack of a Functional VHL Gene Product Sensitizes Renal Cell Carcinoma Cells to the Apoptotic Effects of the Protein Synthesis Inhibitor Verrucarin A

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Girma M. Woldemichael

2012-08-01

Full Text Available Verrucarin A (VA is a small molecule derived from the fungal plant pathogen Myrothecium verrucaria and was identified as a selective inhibitor of clear cell renal cell carcinoma (CCRCC cell proliferation in a high-throughput screen of a library of naturally occurring small molecules. CCRCC arises as a result of loss-of-function mutations in the von Hippel-Lindau (VHL gene. Here we show that VA inhibits protein translation initiation culminating in apoptosis through the extrinsic signaling pathway. Reintroduction of the VHL gene in CCRCC cells afforded resistance to VA's apoptotic effects. This resistance is mediated in part by the formation of stress granules that entrap signaling molecules that initiate the apoptotic signaling cascade. The VHL gene product was found to be a component of stress granules that develop as result of VA treatment. These findings reveal an important role for the VHL gene product in cytotoxic stress response and have important implications for the rational development of VA-related compounds in chemotherapeutic targeting of CCRCC.

Lactobacillus casei Exerts Anti-Proliferative Effects Accompanied by Apoptotic Cell Death and Up-Regulation of TRAIL in Colon Carcinoma Cells

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Santarmaki, Valentina; Aindelis, Georgios; Tompoulidou, Evgenia; Lamprianidou, Eleftheria E.; Saxami, Georgia; Ypsilantis, Petros; Lampri, Evangeli S.; Simopoulos, Constantinos; Kotsianidis, Ioannis; Galanis, Alex; Kourkoutas, Yiannis; Dimitrellou, Dimitra; Chlichlia, Katerina

2016-01-01

Probiotic microorganisms such as lactic acid bacteria (LAB) exert a number of strain-specific health-promoting activities attributed to their immunomodulatory, anti-inflammatory and anti-carcinogenic properties. Despite recent attention, our understanding of the biological processes involved in the beneficial effects of LAB strains is still limited. To this end, the present study investigated the growth-inhibitory effects of Lactobacillus casei ATCC 393 against experimental colon cancer. Administration of live Lactobacillus casei (as well as bacterial components thereof) on murine (CT26) and human (HT29) colon carcinoma cell lines raised a significant concentration- and time-dependent anti-proliferative effect, determined by cell viability assays. Specifically, a dramatic decrease in viability of colon cancer cells co-incubated with 109 CFU/mL L. casei for 24 hours was detected (78% for HT29 and 52% for CT26 cells). In addition, live L. casei induced apoptotic cell death in both cell lines as revealed by annexin V and propidium iodide staining. The significance of the in vitro anti-proliferative effects was further confirmed in an experimental tumor model. Oral daily administration of 109 CFU live L. casei for 13 days significantly inhibited in vivo growth of colon carcinoma cells, resulting in approximately 80% reduction in tumor volume of treated mice. Tumor growth inhibition was accompanied by L. casei-driven up-regulation of the TNF-related apoptosis-inducing ligand TRAIL and down-regulation of Survivin. Taken together, these findings provide evidence for beneficial tumor-inhibitory, anti-proliferative and pro-apoptotic effects driven by this probiotic LAB strain. PMID:26849051

Lactobacillus casei Exerts Anti-Proliferative Effects Accompanied by Apoptotic Cell Death and Up-Regulation of TRAIL in Colon Carcinoma Cells.

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Angeliki Tiptiri-Kourpeti

Full Text Available Probiotic microorganisms such as lactic acid bacteria (LAB exert a number of strain-specific health-promoting activities attributed to their immunomodulatory, anti-inflammatory and anti-carcinogenic properties. Despite recent attention, our understanding of the biological processes involved in the beneficial effects of LAB strains is still limited. To this end, the present study investigated the growth-inhibitory effects of Lactobacillus casei ATCC 393 against experimental colon cancer. Administration of live Lactobacillus casei (as well as bacterial components thereof on murine (CT26 and human (HT29 colon carcinoma cell lines raised a significant concentration- and time-dependent anti-proliferative effect, determined by cell viability assays. Specifically, a dramatic decrease in viability of colon cancer cells co-incubated with 10(9 CFU/mL L. casei for 24 hours was detected (78% for HT29 and 52% for CT26 cells. In addition, live L. casei induced apoptotic cell death in both cell lines as revealed by annexin V and propidium iodide staining. The significance of the in vitro anti-proliferative effects was further confirmed in an experimental tumor model. Oral daily administration of 10(9 CFU live L. casei for 13 days significantly inhibited in vivo growth of colon carcinoma cells, resulting in approximately 80% reduction in tumor volume of treated mice. Tumor growth inhibition was accompanied by L. casei-driven up-regulation of the TNF-related apoptosis-inducing ligand TRAIL and down-regulation of Survivin. Taken together, these findings provide evidence for beneficial tumor-inhibitory, anti-proliferative and pro-apoptotic effects driven by this probiotic LAB strain.

Lactobacillus casei Exerts Anti-Proliferative Effects Accompanied by Apoptotic Cell Death and Up-Regulation of TRAIL in Colon Carcinoma Cells.

Science.gov (United States)

Tiptiri-Kourpeti, Angeliki; Spyridopoulou, Katerina; Santarmaki, Valentina; Aindelis, Georgios; Tompoulidou, Evgenia; Lamprianidou, Eleftheria E; Saxami, Georgia; Ypsilantis, Petros; Lampri, Evangeli S; Simopoulos, Constantinos; Kotsianidis, Ioannis; Galanis, Alex; Kourkoutas, Yiannis; Dimitrellou, Dimitra; Chlichlia, Katerina

2016-01-01

Probiotic microorganisms such as lactic acid bacteria (LAB) exert a number of strain-specific health-promoting activities attributed to their immunomodulatory, anti-inflammatory and anti-carcinogenic properties. Despite recent attention, our understanding of the biological processes involved in the beneficial effects of LAB strains is still limited. To this end, the present study investigated the growth-inhibitory effects of Lactobacillus casei ATCC 393 against experimental colon cancer. Administration of live Lactobacillus casei (as well as bacterial components thereof) on murine (CT26) and human (HT29) colon carcinoma cell lines raised a significant concentration- and time-dependent anti-proliferative effect, determined by cell viability assays. Specifically, a dramatic decrease in viability of colon cancer cells co-incubated with 10(9) CFU/mL L. casei for 24 hours was detected (78% for HT29 and 52% for CT26 cells). In addition, live L. casei induced apoptotic cell death in both cell lines as revealed by annexin V and propidium iodide staining. The significance of the in vitro anti-proliferative effects was further confirmed in an experimental tumor model. Oral daily administration of 10(9) CFU live L. casei for 13 days significantly inhibited in vivo growth of colon carcinoma cells, resulting in approximately 80% reduction in tumor volume of treated mice. Tumor growth inhibition was accompanied by L. casei-driven up-regulation of the TNF-related apoptosis-inducing ligand TRAIL and down-regulation of Survivin. Taken together, these findings provide evidence for beneficial tumor-inhibitory, anti-proliferative and pro-apoptotic effects driven by this probiotic LAB strain.

Exon-skipping strategy by ratio modulation between cytoprotective versus pro-apoptotic clusterin forms increased sensitivity of LNCaP to cell death.

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Abdellatif Essabbani

Full Text Available BACKGROUND: In prostate cancer the secreted form of clusterin (sCLU has been described as an anti-apoptotic protein whose expression is increased after therapeutic intervention, whereas, the nuclear protein form nCLU was reported to have pro-apoptotic properties. METHODOLOGY: In order to provide new therapeutic approaches targeting CLU, we developed a strategy based on exon skipping by using a lentiviral construct to preferentially induce the nuclear spliced form of the protein. The molecular construct was transduced in LNCaP cells for testing the modulation of sensitivity of the transduced cells to pro-apoptotic stress. RESULTS AND CONCLUSIONS: We showed an increase of nCLU/sCLU expression ratio in the prostate cancer cell line "LNCaP" after lentiviral vector-U7 nCLU transduction. Moreover, we showed a significant inhibition of cell proliferation in nCLU-U7 LNCaP cells after treatment with cisplatin and after exposure to ionizing radiation compared to control cells. Finally, we showed that nCLU-U7 LNCaP cells exposure to UV-C significantly reduced an increase of cell death compared to control. Finally, we showed that modulating nCLU expression had profound impact on Ku70/Bax interaction as well as Rad17 expression which could be a key mechanism in sensitizing cells to cell death. In conclusion, this is the first report showing that increasing of nCLU/sCLU expression ratio by using an "on demand alternative splicing" strategy successfully increased sensitivity to radiotherapy and chemotherapy of prostate cancer cells.

Branchial lesions associated with abundant apoptotic cells in oysters Ostrea edulis of Galicia (NW Spain).

Science.gov (United States)

Mirella da Silva, P; Villalba, Antonio; Sunila, Inke

2006-06-12

An experiment to evaluate differences in growth, mortality and disease susceptibility among Ostrea edulis stocks was performed. Five families were produced from each of 4 oyster populations (Irish, Greek and 2 Galician). The spat were transferred to a raft in the Ria de Arousa (Galicia, Spain) for grow-out. Monthly samples of each family were histologically processed from 2001 to 2003. One of the pathological conditions discovered by this study was the occurrence of extensive branchial lesions characterized by haemocytic infiltration and loss of branchial architecture. Furthermore, abundant atypical cells occurred among the haemocytes in the lesions in the branchial connective and epithelial tissues, but rarely in the mantle. These cells were contracted in size with nuclei showing chromatin condensation and fragmentation. Some nuclear chromatin aggregated under the nuclear membranes into crescent shapes, whereas others were uniformly dense. Those characteristics suggested that the cells were apoptotic haemocytes, which was confirmed by transmission electron microscopy (TEM) and by a terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labelling (TUNEL) assay using the Apoptag Kit on paraffin sections. A low prevalence of gill lesions was detected in some, but not all, families of every origin peaking in July 2002 and April 2003. No etiologic agent was identified by either histology or TEM; thus, the cause of the abundance of apoptotic cells remains unclear.

Opening up of plasmalemma type-1 VDAC to form apoptotic "find me signal" pathways is essential in early apoptosis - evidence from the pathogenesis of cystic fibrosis resulting from failure of apoptotic cell clearance followed by sterile inflammation.

Science.gov (United States)

Thinnes, Friedrich P

2014-04-01

Cell membrane-standing type-1 VDAC is involved in cell volume regulation and thus apoptosis. The channel has been shown to figure as a pathway for osmolytes of varying classes, ATP included. An early event in apoptotic cell death is the release of "find me signals" by cells that enter the apoptotic process. ATP is one of those signals. Apoptotic cells this way attract phagocytes for an immunologically silent cell clearance. Thus, whenever apoptosis fails by a blockade of plasmalemma type-1 VDAC processes of sterile inflammation must be assumed for cell elimination. This is evident from a close look on the pathogenetic process of cystic fibrosis (CF). However, in normal airway epithelia two different anion channels cooperate to guarantee an appropriate volume of airway surface liquid (ASL) necessary for surface clearing: the cystic fibrosis conductance regulator (CFTR) and the outwardly rectifying chloride channel (ORCC) complex also called "alternate chloride channel" and under the control of the CFTR. There are arguments, that type-1 VDAC forms the channel part of the ORCC complex, and it has been shown that CFTR and type-1 VDAC co-localize in the apical membranes of human surface respiratory epithelium. In cystic fibrosis, the central cAMP-dependent regulation of ion and water transport via functional CFTR is lost. Here, CFTR molecules do not reach the apical membranes of airway epithelia anymore or work in an insufficient way, respectively. In addition, type-1 VDAC is no longer available to work as a "find me signal" pathway. In consequence, clearing away of apoptotic cells is blocked. There are experimental data on the channel characteristics of type-1 VDAC under the anion channel blocker DIDS (4,4-diisothiocyanato-stilbenedisulphonic acid) that argue in favor of this hypothesis. Together, type-1 VDAC should be kept as a "find me signal" pathway, which may give way to several classes of such signals. Copyright © 2014 Elsevier Inc. All rights reserved.

JNK Controls the Onset of Mitosis in Planarian Stem Cells and Triggers Apoptotic Cell Death Required for Regeneration and Remodeling

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Almuedo-Castillo, María; Crespo, Xenia; Seebeck, Florian; Bartscherer, Kerstin; Salò, Emili; Adell, Teresa

2014-01-01

Regeneration of lost tissues depends on the precise interpretation of molecular signals that control and coordinate the onset of proliferation, cellular differentiation and cell death. However, the nature of those molecular signals and the mechanisms that integrate the cellular responses remain largely unknown. The planarian flatworm is a unique model in which regeneration and tissue renewal can be comprehensively studied in vivo. The presence of a population of adult pluripotent stem cells combined with the ability to decode signaling after wounding enable planarians to regenerate a complete, correctly proportioned animal within a few days after any kind of amputation, and to adapt their size to nutritional changes without compromising functionality. Here, we demonstrate that the stress-activated c-jun–NH2–kinase (JNK) links wound-induced apoptosis to the stem cell response during planarian regeneration. We show that JNK modulates the expression of wound-related genes, triggers apoptosis and attenuates the onset of mitosis in stem cells specifically after tissue loss. Furthermore, in pre-existing body regions, JNK activity is required to establish a positive balance between cell death and stem cell proliferation to enable tissue renewal, remodeling and the maintenance of proportionality. During homeostatic degrowth, JNK RNAi blocks apoptosis, resulting in impaired organ remodeling and rescaling. Our findings indicate that JNK-dependent apoptotic cell death is crucial to coordinate tissue renewal and remodeling required to regenerate and to maintain a correctly proportioned animal. Hence, JNK might act as a hub, translating wound signals into apoptotic cell death, controlled stem cell proliferation and differentiation, all of which are required to coordinate regeneration and tissue renewal. PMID:24922054

Programmed Cell Death and Caspase Functions During Neural Development.

Science.gov (United States)

Yamaguchi, Yoshifumi; Miura, Masayuki

2015-01-01

Programmed cell death (PCD) is a fundamental component of nervous system development. PCD serves as the mechanism for quantitative matching of the number of projecting neurons and their target cells through direct competition for neurotrophic factors in the vertebrate peripheral nervous system. In addition, PCD plays roles in regulating neural cell numbers, canceling developmental errors or noise, and tissue remodeling processes. These findings are mainly derived from genetic studies that prevent cells from dying by apoptosis, which is a major form of PCD and is executed by activation of evolutionarily conserved cysteine protease caspases. Recent studies suggest that caspase activation can be coordinated in time and space at multiple levels, which might underlie nonapoptotic roles of caspases in neural development in addition to apoptotic roles. © 2015 Elsevier Inc. All rights reserved.

faloabi@uniben.edu Antiproliferative and Pro-apoptotic activities

African Journals Online (AJOL)

MICHAEL HORSFALL

Keyword: Persea americana, antiproliferative activity, apoptotic effect, flow ... of the stem bark of Persea americana in MCF-7 cell line by flow cytometer. .... of an electric milling machine. ... Flow Cytometric Measurement Of Cell Proliferation:.

Visualization of proteolytic activity associated with the apoptotic response in cancer cells

Science.gov (United States)

Tice, Brian George

Caspases execute programmed cell death, where low levels of caspase activity are linked to cancer. Chemotherapies utilize induction of apoptosis as a key mechanism for cancer treatment, where caspase-3 is a major player involved in dismantling these aberrant cells. The ability to sensitively measure the initial caspase-3 cleavage events during apoptosis is important for understanding the initiation of this complex cellular process, however, current ensemble methods are not sensitive enough to measure single cleavage events in cells. By utilizing the optical properties of plasmon coupling, peptide-linked gold nanoparticles were developed to enable single molecule imaging of caspase-3 activity in two different cancer systems. Au crown nanoparticles were assembled in a multimeric fashion to overcome the high and heterogeneous background scattering of live cells. In a colon cancer (SW620) cell line challenged with tumor necrosis factor-alpha (TNF-alpha), single molecule trajectories show early stage caspase-3 activation within minutes, which was not detectable by ensemble assays until 23 hours. Variability in caspase-3 activation among the population of cells was identified and likely a result of each cell's specific resistance to death receptor-induced apoptosis. Following these studies, improvements by way of sensitivity and selectivity were tailored into an improved nanosensor construct. Au nanoshell dimers were prepared as a comparably bright construct with 1) reduced heterogeneity compared to the synthesis of the crown nanoparticles and 2) a peptide sequence highly selective for caspase-3. Chronic myeloid leukemia (CML) K562 cells were assessed for their early apoptotic response upon treatment with dasatinib, a clinically approved tyrosine kinase inhibitor that specifically targets BCR-ABL. It has been demonstrated that inhibition of BCR-ABL by dasatinib commits K562 cells to apoptosis. Single molecule experiments with Au nanoshell dimers show caspase-3 activation

Preclinical studies identify non-apoptotic low-level caspase-3 as therapeutic target in pemphigus vulgaris.

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Camille Luyet

Full Text Available The majority of pemphigus vulgaris (PV patients suffer from a live-threatening loss of intercellular adhesion between keratinocytes (acantholysis. The disease is caused by auto-antibodies that bind to desmosomal cadherins desmoglein (Dsg 3 or Dsg3 and Dsg1 in mucous membranes and skin. A currently unresolved controversy in PV is whether apoptosis is involved in the pathogenic process. The objective of this study was to perform preclinical studies to investigate apoptotic pathway activation in PV pathogenesis with the goal to assess its potential for clinical therapy. For this purpose, we investigated mouse and human skin keratinocyte cultures treated with PV antibodies (the experimental Dsg3 monospecific antibody AK23 or PV patients IgG, PV mouse models (passive transfer of AK23 or PVIgG into adult and neonatal mice as well as PV patients' biopsies (n=6. A combination of TUNEL assay, analyses of membrane integrity, early apoptotic markers such as cleaved poly-ADP-ribose polymerase (PARP and the collapse of actin cytoskeleton failed to provide evidence for apoptosis in PV pathogenesis. However, the in vitro and in vivo PV models, allowing to monitor progression of lesion formation, revealed an early, transient and low-level caspase-3 activation. Pharmacological inhibition confirmed the functional implication of caspase-3 in major events in PV such as shedding of Dsg3, keratin retraction, proliferation including c-Myc induction, p38MAPK activation and acantholysis. Together, these data identify low-level caspase-3 activation downstream of disrupted Dsg3 trans- or cis-adhesion as a major event in PV pathogenesis that is non-synonymous with apoptosis and represents, unlike apoptotic components, a promising target for clinical therapy. At a broader level, these results posit that an impairment of adhesive functions in concert with low-level, non-lethal caspase-3 activation can evoke profound cellular changes which may be of relevance for other

Non-THC cannabinoids inhibit prostate carcinoma growth in vitro and in vivo: pro-apoptotic effects and underlying mechanisms.

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De Petrocellis, Luciano; Ligresti, Alessia; Schiano Moriello, Aniello; Iappelli, Mariagrazia; Verde, Roberta; Stott, Colin G; Cristino, Luigia; Orlando, Pierangelo; Di Marzo, Vincenzo

2013-01-01

Cannabinoid receptor activation induces prostate carcinoma cell (PCC) apoptosis, but cannabinoids other than Δ(9) -tetrahydrocannabinol (THC), which lack potency at cannabinoid receptors, have not been investigated. Some of these compounds antagonize transient receptor potential melastatin type-8 (TRPM8) channels, the expression of which is necessary for androgen receptor (AR)-dependent PCC survival. We tested pure cannabinoids and extracts from Cannabis strains enriched in particular cannabinoids (BDS), on AR-positive (LNCaP and 22RV1) and -negative (DU-145 and PC-3) cells, by evaluating cell viability (MTT test), cell cycle arrest and apoptosis induction, by FACS scans, caspase 3/7 assays, DNA fragmentation and TUNEL, and size of xenograft tumours induced by LNCaP and DU-145 cells. Cannabidiol (CBD) significantly inhibited cell viability. Other compounds became effective in cells deprived of serum for 24 h. Several BDS were more potent than the pure compounds in the presence of serum. CBD-BDS (i.p.) potentiated the effects of bicalutamide and docetaxel against LNCaP and DU-145 xenograft tumours and, given alone, reduced LNCaP xenograft size. CBD (1-10 µM) induced apoptosis and induced markers of intrinsic apoptotic pathways (PUMA and CHOP expression and intracellular Ca(2+)). In LNCaP cells, the pro-apoptotic effect of CBD was only partly due to TRPM8 antagonism and was accompanied by down-regulation of AR, p53 activation and elevation of reactive oxygen species. LNCaP cells differentiated to androgen-insensitive neuroendocrine-like cells were more sensitive to CBD-induced apoptosis. These data support the clinical testing of CBD against prostate carcinoma. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

Melipona quadrifasciata (Hymenoptera: Apidae) fat body persists through metamorphosis with a few apoptotic cells and an increased autophagy.

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Santos, Douglas Elias; Azevedo, Dihego Oliveira; Campos, Lúcio Antônio Oliveira; Zanuncio, José Cola; Serrão, José Eduardo

2015-03-01

Fat body, typically comprising trophocytes, provides energy during metamorphosis. The fat body can be renewed once the larval phase is complete or recycled and relocated to form the fat body of the adult insect. This study aims to identify the class of programmed cell death that occurs within the fat body cells during the metamorphosis of the stingless bee Melipona quadrifasciata. Using immunodetection techniques, the fat body of the post-defecating larvae and the white-, pink-, brown-, and black-eyed pupae were tested for cleaved caspase-3 and DNA integrity, followed by ultrastructural analysis and identification of autophagy using RT-PCR for the Atg1 gene. The fat body of M. quadrifasciata showed some apoptotic cells positive for cleaved caspase-3, although without DNA fragmentation. During development, the fat body cells revealed an increased number of mitochondria and free ribosomes, in addition to higher amounts of autophagy Atg1 mRNA, than that of the pupae. The fat body of M. quadrifasciata showed few cells which underwent apoptosis, but there was evidence of increased autophagy at the completion of the larval stage. All together, these data show that some fat body cells persist during metamorphosis in the stingless bee M. quadrifasciata.

Antiproliferative and Pro-Apoptotic Effect of Novel Nitro-Substituted Hydroxynaphthanilides on Human Cancer Cell Lines

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Tereza Kauerova

2016-07-01

Full Text Available Ring-substituted hydroxynaphthanilides are considered as cyclic analogues of salicylanilides, compounds possessing a wide range of pharmacological activities, including promising anticancer properties. The aim of this study was to evaluate the potential anticancer effect of novel nitro-substituted hydroxynaphthanilides with a special focus on structure-activity relationships. The antiproliferative effect was assessed by Water Soluble Tetrazolium Salts-1 (WST-1 assay, and cytotoxicity was evaluated via dye exclusion test. Flow cytometry was used for cell cycle analysis and detection of apoptosis using Annexin V-FITC/PI assay. Protein expression was estimated by Western blotting. Our data indicate that the potential to cause the antiproliferative effect increases with the shift of the nitro substituent from the ortho- to the para-position. The most potent compounds, 3-hydroxy-N-(3-nitrophenylnaphthalene-2-carboxamide (2, and 2-hydroxy-N-(4-nitrophenyl-naphthalene-1-carboxamide (6 showed antiproliferative activity against THP-1 and MCF-7 cancer cells without affecting the proliferation of 3T3-L1 non-tumour cells. Compounds 2 and 6 induced the accumulation of THP-1 and MCF-7 cells in G1 phase associated with the downregulation of cyclin E1 protein levels, while the levels of cyclin B1 were not affected. Moreover, compound 2 was found to exert the pro-apoptotic effect on the THP-1 cells. These results suggest that hydroxynaphthanilides might represent a potential model structure for the development of novel anticancer agents.

Mycobacterium tuberculosis infection induces non-apoptotic cell death of human dendritic cells

LENUS (Irish Health Repository)

Ryan, Ruth CM

2011-10-24

Abstract Background Dendritic cells (DCs) connect innate and adaptive immunity, and are necessary for an efficient CD4+ and CD8+ T cell response after infection with Mycobacterium tuberculosis (Mtb). We previously described the macrophage cell death response to Mtb infection. To investigate the effect of Mtb infection on human DC viability, we infected these phagocytes with different strains of Mtb and assessed viability, as well as DNA fragmentation and caspase activity. In parallel studies, we assessed the impact of infection on DC maturation, cytokine production and bacillary survival. Results Infection of DCs with live Mtb (H37Ra or H37Rv) led to cell death. This cell death proceeded in a caspase-independent manner, and without nuclear fragmentation. In fact, substrate assays demonstrated that Mtb H37Ra-induced cell death progressed without the activation of the executioner caspases, 3\\/7. Although the death pathway was triggered after infection, the DCs successfully underwent maturation and produced a host-protective cytokine profile. Finally, dying infected DCs were permissive for Mtb H37Ra growth. Conclusions Human DCs undergo cell death after infection with live Mtb, in a manner that does not involve executioner caspases, and results in no mycobactericidal effect. Nonetheless, the DC maturation and cytokine profile observed suggests that the infected cells can still contribute to TB immunity.

Ultrastructural Complexity of Nuclear Components During Early Apoptotic Phases in Breast Cancer Cells

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Christian Castelli

2001-01-01

Full Text Available Fractal morphometry was used to investigate the ultrastructural features of the plasma membrane, perinuclear membrane and nuclear chromatin in SK‐BR‐3 human breast cancer cells undergoing apoptosis. Cells were incubated with 1 μM calcimycin (A23187 for 24 h. Cells in the early stage of apoptosis had fractal dimension (FD values indicating that their plasma membranes were less rough (lower FD than those of control cells, while their perinuclear membranes were unaffected. Changes of the chromatin texture within the entire nucleus and in selected nuclear domains were more pronounced in treated cells. This confirms that the morphological reorganization imputable to a loss of structural complexity (reduced FD occurs in the early stage of apoptosis, is accompanied by the inhibition of distinct enzymatic events and precedes the onset of conventional cellular markers, which can only be detected during the active phases of the apoptotic process.

Single cell analysis of caspase-3 in apoptotic and non-apoptotic cells during mouse limb development

Czech Academy of Sciences Publication Activity Database

Adamová, Eva; Klepárník, Karel; Matalová, E.

2014-01-01

Roč. 3, - (2014), PP58 ISSN 2052-1219. [European Calcified Tissue Society Congress /41./. 17.05.2014-20.05.2014, Praha] R&D Projects: GA ČR GAP206/11/2377; GA ČR(CZ) GA14-28254S Institutional support: RVO:68081715 Keywords : single cell analysis * caspase-3 * mouse limb development Subject RIV: CB - Analytical Chemistry, Separation

Human breast tumor cells are more resistant to cardiac glycoside toxicity than non-tumorigenic breast cells.

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Rebecca J Clifford

Full Text Available Cardiotonic steroids (CTS, specific inhibitors of Na,K-ATPase activity, have been widely used for treating cardiac insufficiency. Recent studies suggest that low levels of endogenous CTS do not inhibit Na,K-ATPase activity but play a role in regulating blood pressure, inducing cellular kinase activity, and promoting cell viability. Higher CTS concentrations inhibit Na,K-ATPase activity and can induce reactive oxygen species, growth arrest, and cell death. CTS are being considered as potential novel therapies in cancer treatment, as they have been shown to limit tumor cell growth. However, there is a lack of information on the relative toxicity of tumor cells and comparable non-tumor cells. We have investigated the effects of CTS compounds, ouabain, digitoxin, and bufalin, on cell growth and survival in cell lines exhibiting the full spectrum of non-cancerous to malignant phenotypes. We show that CTS inhibit membrane Na,K-ATPase activity equally well in all cell lines tested regardless of metastatic potential. In contrast, the cellular responses to the drugs are different in non-tumor and tumor cells. Ouabain causes greater inhibition of proliferation and more extensive apoptosis in non-tumor breast cells compared to malignant or oncogene-transfected cells. In tumor cells, the effects of ouabain are accompanied by activation of anti-apoptotic ERK1/2. However, ERK1/2 or Src inhibition does not sensitize tumor cells to CTS cytotoxicity, suggesting that other mechanisms provide protection to the tumor cells. Reduced CTS-sensitivity in breast tumor cells compared to non-tumor cells indicates that CTS are not good candidates as cancer therapies.

Role and regulation of apoptotic cell death in the kidney. Y2K update.

Science.gov (United States)

Ortiz, A; Lorz, C; Catalan, M P; Justo, P; Egido, J

2000-08-01

Apoptosis is an active form of cell death that, in balance with mitosis, regulates cell number. Cell number abnormalities are a frequent feature of renal disease. We now review current concepts on the molecular regulation of apoptotic cell death, including the influence of survival and lethal factors from the extracellular microenvironment as well as the role of intracellular regulators of apoptosis, such as death receptors, proapoptotic and antiapoptotic bcl2-related proteins, the mitochondria and caspases. In addition the role of apoptosis in the genesis, persistence and progression and remodeling and resolution of renal injury is discussed. Information on the expression and function of apoptosis regulatory proteins in specific renal syndromes is summarized. Finally, future perspectives in research and clinical intervention are discussed.

Withaferin A Suppresses Anti-apoptotic BCL2, Bcl-xL, XIAP and ...

African Journals Online (AJOL)

apoptotic ... Quantitative real-time polymerase chain reaction (qPCR) was performed using Taq PCR Master ... Keywords: Anti-apoptotic genes, Cervical cancer, Apoptosis, Cell viability, BCL2, .... polyclonal anti-rabbit immunoglobulin HRP-linked.

Taurine protects HK-2 cells from oxidized LDL-induced cytotoxicity via the ROS-mediated mitochondrial and p53-related apoptotic pathways

Energy Technology Data Exchange (ETDEWEB)

Chang, Chun-Yu [Graduate Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Shen, Chao-Yu [School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan (China); Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan (China); School of Medicine, Chung Shan Medical University, Taichung, Taiwan (China); Kang, Chao-Kai [Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan, (China); Sher, Yuh-Pyng [Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan (China); Center for Molecular Medicine, China Medical University Hospital, Taichung 404, Taiwan (China); Sheu, Wayne H.-H. [Graduate Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Division of Endocrinology and Metabolism, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan (China); School of Medicine, National Yang Ming University, Taipei, Taiwan (China); School of Medicine, National Defense Medical Center, Taipei, Taiwan (China); Chang, Chia-Che, E-mail: chia_che@dragon.nchu.edu.tw [Graduate Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan (China); Lee, Tsung-Han, E-mail: thlee@email.nchu.edu.tw [Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan, (China); Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan (China); Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan (China); Department of Biological Science and Technology, China Medical University, Taichung, Taiwan (China)

2014-09-15

Oxidized LDL (oxLDL) induces a pro-oxidative environment and promotes apoptosis, causing the progression of renal diseases in humans. Taurine is a semi-essential amino acid in mammals and has been shown to be a potent endogenous antioxidant. The kidney plays a pivotal role in maintaining the balance of taurine. However, the mechanisms underlying the protective effects of taurine against oxLDL-induced injury in renal epithelial cells have not been clarified. In the present study, we investigated the anti-apoptotic effects of taurine on human proximal tubular epithelial (HK-2) cells exposed to oxLDL and explored the related mechanisms. We observed that oxLDL increased the contents of ROS and of malondialdehyde (MDA), which is a lipid peroxidation by-product that acts as an indicator of the cellular oxidation status. In addition, oxLDL induced cell death and apoptosis in HK-2 cells. Pretreatment with taurine at 100 μM significantly attenuated the oxLDL-induced cytotoxicity. We determined that oxLDL triggered the phosphorylation of ERK and, in turn, the activation of p53 and other apoptosis-related events, including calcium accumulation, destabilization of the mitochondrial permeability and disruption of the balance between pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins. The malfunctions induced by oxLDL were effectively blocked by taurine. Thus, our results suggested that taurine exhibits potential therapeutic activity by preventing oxLDL-induced nephrotoxicity. The inhibition of oxLDL-induced epithelial apoptosis by taurine was at least partially due to its anti-oxidant activity and its ability to modulate the ERK and p53 apoptotic pathways. - Highlights: • Oxidized LDL induced cytotoxicity and apoptosis in HK-2 cells. • Pretreatment with taurine attenuated oxLDL-induced nephrotoxicity. • Taurine protected against renal damages through inhibition of ROS generation. • Taurine prevented apoptosis through modulation of the p53 phosphorylation.

Taurine protects HK-2 cells from oxidized LDL-induced cytotoxicity via the ROS-mediated mitochondrial and p53-related apoptotic pathways

International Nuclear Information System (INIS)

Chang, Chun-Yu; Shen, Chao-Yu; Kang, Chao-Kai; Sher, Yuh-Pyng; Sheu, Wayne H.-H.; Chang, Chia-Che; Lee, Tsung-Han

2014-01-01

Oxidized LDL (oxLDL) induces a pro-oxidative environment and promotes apoptosis, causing the progression of renal diseases in humans. Taurine is a semi-essential amino acid in mammals and has been shown to be a potent endogenous antioxidant. The kidney plays a pivotal role in maintaining the balance of taurine. However, the mechanisms underlying the protective effects of taurine against oxLDL-induced injury in renal epithelial cells have not been clarified. In the present study, we investigated the anti-apoptotic effects of taurine on human proximal tubular epithelial (HK-2) cells exposed to oxLDL and explored the related mechanisms. We observed that oxLDL increased the contents of ROS and of malondialdehyde (MDA), which is a lipid peroxidation by-product that acts as an indicator of the cellular oxidation status. In addition, oxLDL induced cell death and apoptosis in HK-2 cells. Pretreatment with taurine at 100 μM significantly attenuated the oxLDL-induced cytotoxicity. We determined that oxLDL triggered the phosphorylation of ERK and, in turn, the activation of p53 and other apoptosis-related events, including calcium accumulation, destabilization of the mitochondrial permeability and disruption of the balance between pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins. The malfunctions induced by oxLDL were effectively blocked by taurine. Thus, our results suggested that taurine exhibits potential therapeutic activity by preventing oxLDL-induced nephrotoxicity. The inhibition of oxLDL-induced epithelial apoptosis by taurine was at least partially due to its anti-oxidant activity and its ability to modulate the ERK and p53 apoptotic pathways. - Highlights: • Oxidized LDL induced cytotoxicity and apoptosis in HK-2 cells. • Pretreatment with taurine attenuated oxLDL-induced nephrotoxicity. • Taurine protected against renal damages through inhibition of ROS generation. • Taurine prevented apoptosis through modulation of the p53 phosphorylation

Interaction of DNA-lesions induced by sodium fluoride and radiation and its influence in apoptotic induction in cancer cell lines

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Santosh Podder

2015-01-01

Full Text Available Fluoride is an essential trace element but also an environmental contaminant with major sources of exposure being drinking water, food and pesticides. Previous studies showed that sodium fluoride (NaF at 5 mM or more is required to induce apoptosis and chromosome aberrations and proposed that DNA damage and apoptosis play an important role in toxicity of excessive fluoride. The aim of this study is directed to understand the nature of DNA-lesions induced by NaF by allowing its interaction with radiation induced DNA-lesions. NaF 5 mM was used after observing inability to induce DNA damages and apoptosis by single exposure with 50 μM or 1 mM NaF. Co-exposure to NaF and radiation significantly increased the frequency of aberrant metaphases and exchange aberrations in human lymphocytes and arrested the cells in G1 stage instead of apoptotic death. Flow cytometric analysis, DNA fragmentation and PARP-cleavage analysis clearly indicated that 5 mM NaF together with radiation (1 Gy induced apoptosis in both U87 and K562 cells due to down regulation of expression of anti-apoptotic proteins, like Bcl2 in U87 and inhibitors of apoptotic proteins like survivin and cIAP in K562 cells. This study herein suggested that single exposure with extremely low concentration of NaF unable to induce DNA lesions whereas higher concentration induced DNA lesions interact with the radiation-induced DNA lesions. Both are probably repaired rapidly thus showed increased interactive effect. Coexposure to NaF and radiation induces more apoptosis in cancer cell lines which could be due to increased exchange aberrations through lesions interaction and downregulating anti-apoptotic genes.

Lack of a Functional VHL Gene Product Sensitizes Renal Cell Carcinoma Cells to the Apoptotic Effects of the Protein Synthesis Inhibitor Verrucarin A12

Science.gov (United States)

Woldemichael, Girma M; Turbyville, Thomas J; Vasselli, James R; Linehan, W Marston; McMahon, James B

2012-01-01

Verrucarin A (VA) is a small molecule derived from the fungal plant pathogen Myrothecium verrucaria and was identified as a selective inhibitor of clear cell renal cell carcinoma (CCRCC) cell proliferation in a high-throughput screen of a library of naturally occurring small molecules. CCRCC arises as a result of loss-of-function mutations in the von Hippel-Lindau (VHL) gene. Here we show that VA inhibits protein translation initiation culminating in apoptosis through the extrinsic signaling pathway. Reintroduction of the VHL gene in CCRCC cells afforded resistance to VA's apoptotic effects. This resistance is mediated in part by the formation of stress granules that entrap signaling molecules that initiate the apoptotic signaling cascade. The VHL gene product was found to be a component of stress granules that develop as result of VA treatment. These findings reveal an important role for the VHL gene product in cytotoxic stress response and have important implications for the rational development of VA-related compounds in chemotherapeutic targeting of CCRCC. PMID:22952429

Involvement of caspase-dependent and -independent apoptotic pathways in cisplatin-induced apoptosis

Science.gov (United States)

Liu, Lei; Zhang, Yingjie; Wang, Xianwang

2009-02-01

Cisplatin, an efficient anticancer agent, can trigger multiple apoptotic pathways in cancer cells. However, the signal transduction pathways in response to cisplatin-based chemotherapy are complicated, and the mechanism is not fully understood. In current study, we showed that, during cisplatin-induced apoptosis of human lung adenocarcinoma cells, both the caspase-dependent and -independent pathways were activated. Herein, we reported that after cisplatin treatment, the activities of caspase-9/-3 were sharply increased; pre-treatment with Z-LEHD-fmk (inhibitor of caspase-9), Z-DEVD-fmk (inhibitor of caspase-3), and Z-VAD-fmk (a pan-caspase inhibitor) increased cell viability and decreased apoptosis, suggesting that caspase-mediated apoptotic pathway was activated following cisplatin treatment. Confocal imaging of the cells transfected with AIF-GFP demonstrated that AIF release occurred about 9 h after cisplatin treatment. The event proceeded progressively over time, coinciding with a nuclear translocation and lasting for more than 2 hours. Down-regulation of AIF by siRNA also significantly increased cell viability and decreased apoptosis, these results suggested that AIF-mediated caspase-independent apoptotic pathway was involved in cispatin-induced apoptosis. In conclusion, the current study demonstrated that both caspase-dependent and -independent apoptotic pathways were involved in cisplatin-induced apoptosis in human lung adenocarcinoma cells.

Curcumin induces apoptotic cell death of activated human CD4+ T cells via increasing endoplasmic reticulum stress and mitochondrial dysfunction.

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Zheng, Min; Zhang, Qinggao; Joe, Yeonsoo; Lee, Bong Hee; Ryu, Do Gon; Kwon, Kang Beom; Ryter, Stefan W; Chung, Hun Taeg

2013-03-01

Curcumin, a natural polyphenolic antioxidant compound, exerts well-known anti-inflammatory and immunomodulatory effects, the latter which can influence the activation of immune cells including T cells. Furthermore, curcumin can inhibit the expression of pro-inflammatory cytokines and chemokines, through suppression of the NF-κB signaling pathway. The beneficial effects of curcumin in diseases such as arthritis, allergy, asthma, atherosclerosis, diabetes and cancer may be due to its immunomodulatory properties. We studied the potential of curcumin to modulate CD4+ T cells-mediated autoimmune disease, by examining the effects of this compound on human CD4+ lymphocyte activation. Stimulation of human T cells with PHA or CD3/CD28 induced IL-2 mRNA expression and activated the endoplasmic reticulum (ER) stress response. The treatment of T cells with curcumin induced the unfolded protein response (UPR) signaling pathway, initiated by the phosphorylation of PERK and IRE1. Furthermore, curcumin increased the expression of the ER stress associated transcriptional factors XBP-1, cleaved p50ATF6α and C/EBP homologous protein (CHOP) in human CD4+ and Jurkat T cells. In PHA-activated T cells, curcumin further enhanced PHA-induced CHOP expression and reduced the expression of the anti-apoptotic protein Bcl-2. Finally, curcumin treatment induced apoptotic cell death in activated T cells via eliciting an excessive ER stress response, which was reversed by the ER-stress inhibitor 4-phenylbutyric acid or transfection with CHOP-specific siRNA. These results suggest that curcumin can impact both ER stress and mitochondria functional pathways, and thereby could be used as a promising therapy in the context of Th1-mediated autoimmune diseases. Copyright © 2013 Elsevier B.V. All rights reserved.

Downregulated TIPE2 is associated with poor prognosis and promotes cell proliferation in non-small cell lung cancer

International Nuclear Information System (INIS)

Li, Yuexia; Li, Xiaohui; Liu, Gang; Sun, Rongqing; Wang, Lirui; Wang, Jing; Wang, Hongmin

2015-01-01

Highlights: • TIPE2 is down-regulated in NSCLC tissues. • TIPE2 inhibits NSCLC cell proliferation, colony formation and invasion. • TIPE2 reduces the anti-apoptotic Bcl-XL protein and mesenchymal marker N-cadherin expression. - Abstract: The present study aims to investigate the expression pattern of TIPE2 protein and its clinical significance in human non-small cell lung cancer (NSCLC). We investigated the expression levels of TIPE2 in 96 NSCLC tumor samples by immunohistochemistry and then analyzed its clinical significance. Furthermore, the role of TIPE2 on the biological properties of the NSCLC cell line H1299 and A549 was experimentally tested in vitro and in vivo. We found that the expression level of TIPE2 was significantly higher in normal lung tissues compared with NSCLC tissues (P < 0.001), and TIPE2 downregulation was significantly correlated with advanced TNM stage (P = 0.006). TIPE2 expression was lower in lung cancer cell lines than normal bronchial cell line HBE. Transfection of TIPE2 plasmid was performed in H1299 and A549 cells. TIPE2 overexpression inhibited lung cancer cell proliferation, colony formation and cell invasive in vitro, and prevented lung tumor growth in vivo. In addition, TIPE2 transfection reduced the anti-apoptotic Bcl-XL protein and mesenchymal marker N-cadherin expression. Taken together, our results demonstrate that TIPE2 might serve as a tumor suppressor in NSCLC progression

Downregulated TIPE2 is associated with poor prognosis and promotes cell proliferation in non-small cell lung cancer

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Li, Yuexia [Intensive Care Unit, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052 (China); Li, Xiaohui [Department of Cardiovascular Surgery, Henan Provincial People’s Hospital, Zhengzhou, Henan 450003 (China); Liu, Gang; Sun, Rongqing; Wang, Lirui [Intensive Care Unit, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052 (China); Wang, Jing, E-mail: jing_wang1980@163.com [Department of Respiratory Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052 (China); Wang, Hongmin, E-mail: hmwangzz@126.com [Department of Respiratory Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052 (China)

2015-01-30

Highlights: • TIPE2 is down-regulated in NSCLC tissues. • TIPE2 inhibits NSCLC cell proliferation, colony formation and invasion. • TIPE2 reduces the anti-apoptotic Bcl-XL protein and mesenchymal marker N-cadherin expression. - Abstract: The present study aims to investigate the expression pattern of TIPE2 protein and its clinical significance in human non-small cell lung cancer (NSCLC). We investigated the expression levels of TIPE2 in 96 NSCLC tumor samples by immunohistochemistry and then analyzed its clinical significance. Furthermore, the role of TIPE2 on the biological properties of the NSCLC cell line H1299 and A549 was experimentally tested in vitro and in vivo. We found that the expression level of TIPE2 was significantly higher in normal lung tissues compared with NSCLC tissues (P < 0.001), and TIPE2 downregulation was significantly correlated with advanced TNM stage (P = 0.006). TIPE2 expression was lower in lung cancer cell lines than normal bronchial cell line HBE. Transfection of TIPE2 plasmid was performed in H1299 and A549 cells. TIPE2 overexpression inhibited lung cancer cell proliferation, colony formation and cell invasive in vitro, and prevented lung tumor growth in vivo. In addition, TIPE2 transfection reduced the anti-apoptotic Bcl-XL protein and mesenchymal marker N-cadherin expression. Taken together, our results demonstrate that TIPE2 might serve as a tumor suppressor in NSCLC progression.

Serratia marcescens Induces Apoptotic Cell Death in Host Immune Cells via a Lipopolysaccharide- and Flagella-dependent Mechanism*

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Ishii, Kenichi; Adachi, Tatsuo; Imamura, Katsutoshi; Takano, Shinya; Usui, Kimihito; Suzuki, Kazushi; Hamamoto, Hiroshi; Watanabe, Takeshi; Sekimizu, Kazuhisa

2012-01-01

Injection of Serratia marcescens into the blood (hemolymph) of the silkworm, Bombyx mori, induced the activation of c-Jun NH2-terminal kinase (JNK), followed by caspase activation and apoptosis of blood cells (hemocytes). This process impaired the innate immune response in which pathogen cell wall components, such as glucan, stimulate hemocytes, leading to the activation of insect cytokine paralytic peptide. S. marcescens induced apoptotic cell death of silkworm hemocytes and mouse peritoneal macrophages in vitro. We searched for S. marcescens transposon mutants with attenuated ability to induce apoptosis of silkworm hemocytes. Among the genes identified, disruption mutants of wecA (a gene involved in lipopolysaccharide O-antigen synthesis), and flhD and fliR (essential genes in flagella synthesis) showed reduced motility and impaired induction of mouse macrophage cell death. These findings suggest that S. marcescens induces apoptosis of host immune cells via lipopolysaccharide- and flagella-dependent motility, leading to the suppression of host innate immunity. PMID:22859304

Synthesis and Characterization of a New Benzoindole Derivative with Apoptotic Activity Against Colon Cancer Cells.

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Hajiaghaalipour, Fatemeh; Faraj, Fadhil L; Bagheri, Elham; Ali, Hapipah M; Abdulla, Mahmood Ameen; Majid, Nazia A

2017-01-01

Colorectal cancer is the third most common form of cancer in both men and women around the world. The chemistry and biological study of heterocyclic compounds have been an interesting area for a long time in pharmaceutical and medicinal chemistry. A new synthetic compound, 2-(1,1-dimethyl-1H-benzo[e]indol-2-yl)-3-((2-hydroxyphenyl)amino) acrylaldehyde, abbreviated as DBID, was prepared through the reaction of 2-(diformylmethylidene)-1,1- dimethylbenzo[e]indole with 2-aminophenol. The chemical structure of the synthesized compound was characterized by 1H NMR, 13C NMR and APT-NMR spectroscopy and confirmed by elemental analysis (CHN). The compound was screened for the antiproliferation effect against colorectal cancer cell line, HCT 116 and its possible mechanism of action was elucidated. To determine the IC50 value, the MTT assay was used and its apoptosisinducing effect was investigated. DBID inhibited the proliferation of HCT 116 cells with an IC50 of 9.32 µg/ml and significantly increased the levels of caspase -8, -9 and -3/7 in the treated cells compared to untreated cells. Apoptosis features in HCT 116 cell was detected in treated cells by using the AO/PI staining that confirmed that the cells had undergone remarkable morphological changes in apoptotic bodies. Furthermore, this changes in expression of caspase -8, -9 and -3 were confirmed by gene and protein quantification using RT-PCR and western blot analysis, respectively. The current study showed that the DBID compound has demonstrated chemotherapeutic activity which was evidenced by significant increases in the expression and activation of caspase and exploit the apoptotic signaling pathways to trigger cancer cell death. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Quantification of apoptotic DNA fragmentation in a transformed uterine epithelial cell line, HRE-H9, using capillary electrophoresis with laser-induced fluorescence detector (CE-LIF).

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Fiscus, R R; Leung, C P; Yuen, J P; Chan, H C

2001-01-01

Apoptotic cell death of uterine epithelial cells is thought to play an important role in the onset of menstruation and the successful implantation of an embryo during early pregnancy. Abnormal apoptosis in these cells can result in dysmenorrhoea and infertility. In addition, decreased rate of epithelial apoptosis likely contributes to endometriosis. A key step in the onset of apoptosis in these cells is cleavage of the genomic DNA between nucleosomes, resulting in polynucleosomal-sized fragments of DNA. The conventional technique for assessing apoptotic DNA fragmentation uses agarose (slab) gel electrophoresis (i.e. DNA laddering). However, recent technological advances in the use of capillary electrophoresis (CE), particularly the introduction of the laser-induced fluorescence detector (LIF), has made it possible to perform DNA laddering with improved automation and much greater sensitivity. In the present study, we have further developed the CE-LIF technique by using a DNA standard curve to quantify accurately the amount of DNA in the apoptotic DNA fragments and have applied this new quantitative technique to study apoptosis in a transformed uterine epithelial cell line, the HRE-H9 cells. Apoptosis was induced in the HRE-H9 cells by serum deprivation for 5, 7 and 24 h, resulting in increased DNA fragmentation of 2.2-, 3.1- and 6.2-fold, respectively, above the 0 h or plus-serum controls. This ultrasensitive CE-LIF technique provides a novel method for accurately measuring the actions of pro- or anti-apoptotic agents or conditions on uterine epithelial cell lines. Copyright 2001 Academic Press.

Cytotoxic, genotoxic and apoptotic effects of naringenin-oxime relative to naringenin on normal and cancer cell lines

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Abdurrahim Kocyigit

2016-10-01

Conclusions: This study showed that both NG-Ox and NG possess cytotoxic, genotoxic and apoptotic activities through the production of ROS on cells, NG-Ox being the more effective one. Therefore, derived compound of NG might be used as antiproliferative agents for the treatment of cancer.

Cytotoxic and Pro-Apoptotic Effects of Honey Bee Venom and Chrysin on Human Ovarian Cancer Cells

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Elaheh Amini

2015-06-01

Full Text Available Background: The anti-cancer effects of honey bee venom (BV and chrysin might open a new window for treatment of chemo-resistant cancers. This study was designed to evaluate cytotoxic and pro-apoptotic effects of BV and chrysin on A2780cp cistplatin- resistant human ovarian cancer cells. Methods: As per the study objectives, A2780cp cells were categorized to 4 groups: 3 experiment groups (treated either with BV or chrysin or BV + chrysin and 1 control group (untreated cells.  Experiment group cells were cultured and treated by different concentrations of BV and chrysin for 24 hours. Then, experiment and control cells were studied with MTT assay, Annexin V-FITC, DAPI and Acridine Orange / Propidium Iodide statining, flow cytometry, caspase-3 and -9 assay, measurement of intracellular level of reactive oxygen species (ROS and RT-PCR. Results: MTT assay showed that 8 μg/mL BV, 40 µg/ml chrysin and 6 + 15 μg/mL BV + chrysin co-treatment induced 50% cell death on A2780cp cells compared with controls (P < 0.001. Morphological observations by inverted and fluorescent microscopy revealed ROS generation and apoptotic cell death under exposure to BV or chrysin or BV + chrysin co-treatment. Caspase-3 and -9 assay demonstrated that BV and chrysin triggered apoptosis through intrinsic pathway and RT-PCR demonstrated down-regulation of Bcl-2. Conclusion: Honey bee venom and chrysin are effective for destroying chemoresistant ovarian cancer cells through activation of intrinsic apoptosis, which propose them as potential candidates to be used in development of improved chemotherapeutic agents in the future.

Pyridine nucleotides in regulation of cell death and survival by redox and non-redox reactions.

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Novak Kujundžić, Renata; Žarković, Neven; Gall Trošelj, Koraljka

2014-01-01

Changes of the level and ratios of pyridine nucleotides determine metabolism- dependent cellular redox status and the activity of poly(ADP-ribose) polymerases (PARPs) and sirtuins, thereby influencing several processes closely related to cell survival and death. Pyridine nucleotides participate in numerous metabolic reactions whereby their net cellular level remains constant, but the ratios of NAD+/NADP+ and NADH/NADPH oscillate according to metabolic changes in response to diverse stress signals. In non-redox reactions, NAD+ is degraded and quickly, afterward, resynthesized in the NAD+ salvage pathway, unless overwhelming activation of PARP-1 consumes NAD+ to the point of no return, when the cell can no longer generate enough ATP to accommodate NAD+ resynthesis. The activity of PARP-1 is mandatory for the onset of cytoprotective autophagy on sublethal stress signals. It has become increasingly clear that redox status, largely influenced by the metabolism-dependent composition of the pyridine nucleotides pool, plays an important role in the synthesis of pro-apoptotic and anti-apoptotic sphingolipids. Awareness of the involvement of the prosurvival sphingolipid, sphingosine-1-phosphate, in transition from inflammation to malignant transformation has recently emerged. Here, the participation of pyridine nucleotides in redox and non-redox reactions, sphingolipid metabolism, and their role in cell fate decisions is reviewed.

Co-ordinate but disproportionate activation of apoptotic, regenerative and inflammatory pathways characterizes the liver response to acute amebic infection.

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Pelosof, Lorraine C; Davis, Paul H; Zhang, Zhi; Zhang, Xiaochun; Stanley, Samuel L

2006-03-01

The liver has the remarkable ability to respond to injury with repair and regeneration. The protozoan parasite Entamoeba histolytica is the major cause of liver abscess worldwide. We report a transcriptional analysis of the response of mouse liver to E. histolytica infection, the first study looking at acute liver infection by a non-viral pathogen. Focusing on early time points, we identified 764 genes with altered transcriptional levels in amebic liver abscess. The response to infection is rapid and complex, with concurrent increased expression of genes linked to host defence through IL-1, TLR2, or interferon-induced pathways, liver regeneration via activation of IL-6 pathways, and genes associated with programmed cell death possibly through TNFalpha or Fas pathways. A comparison of amebic liver infection with the liver response to partial hepatectomy or toxins reveals striking similarities between amebic liver abscess and non-infectious injury in key components of the liver regeneration pathways. However, the response in amebic liver abscess is biased towards apoptosis when compared with acute liver injury from hepatectomy, toxins, or other forms of liver infection. E. histolytica infection of the liver simultaneously activates inflammatory, regenerative and apoptotic pathways, but the sum of these early responses is biased towards programmed cell death.

Pre-apoptotic response to therapeutic DNA damage involves protein modulation of Mcl-1, Hdm2 and Flt3 in acute myeloid leukemia cells

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Hovland Randi

2007-05-01

Full Text Available Abstract Background Acute myeloid leukemia (AML cells are characterized by non-mutated TP53, high levels of Hdm2, and frequent mutation of the Flt3 receptor tyrosine kinase. The juxtamembrane mutation of FLT3 is the strongest independent marker for disease relapse and is associated with elevated Bcl-2 protein and p53 hyper-phosphorylation in AML. DNA damage forms the basic mechanism of cancer cell eradication in current therapy of AML. Hdm2 and pro-apoptotic Bcl-2 members are among the most intensely induced genes immediately after chemotherapy and Hdm2 is proposed a role in receptor tyrosine kinase regulation. Thus we examined the DNA damage related modulation of these proteins in relation to FLT3 mutational status and induction of apoptosis. Results Within one hour after exposure to ionizing radiation (IR, the AML cells (NB4, MV4-11, HL-60, primary AML cells showed an increase in Flt3 protein independent of mRNA levels, while the Hdm2 protein decreased. The FLT3 mutant MV4-11 cells were resistant to IR accompanied by presence of both Mcl-1 and Hdm2 protein three hours after IR. In contrast, the FLT3 wild type NB4 cells responded to IR with apoptosis and pre-apoptotic Mcl-1 down regulation. Daunorubicin (DNR induced continuing down regulation of Hdm2 and Mcl-1 in both cell lines followed by apoptosis. Conclusion Both IR and DNR treatment resulted in concerted protein modulations of Mcl-1, Hdm2 and Flt3. Cell death induction was associated with persistent attenuation of Mcl-1 and Hdm2. These observations suggest that defining the pathway(s modulating Flt3, Hdm2 and Mcl-1 may propose new strategies to optimize therapy for the relapse prone FLT3 mutated AML patients.

Nogo-B (Reticulon-4B) functions as a negative regulator of the apoptotic pathway through the interaction with c-FLIP in colorectal cancer cells.

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Kawaguchi, Nao; Tashiro, Keitaro; Taniguchi, Kohei; Kawai, Masaru; Tanaka, Keitaro; Okuda, Junji; Hayashi, Michihiro; Uchiyama, Kazuhisa

2018-08-01

Nogo-B is a member of the Nogo/Reticulon-4 family and has been reported to be an inducer of apoptosis in certain types of cancer cells. However, the role of Nogo-B in human cancer remains less understood. Here, we demonstrated the functions of Nogo-B in colorectal cancer cells. In clinical colorectal cancer specimens, Nogo-B was obviously overexpressed, as determined by immunohistochemistry; and Western blot analysis showed its expression level to be significantly up-regulated. Furthermore, knockdown of Nogo-B in two colorectal cancer cell lines, SW480 and DLD-1, by transfection with si-RNA (siR) resulted in significantly reduced cell viability and a dramatic increase in apoptosis with insistent overexpression of cleaved caspase-8 and cleaved PARP. The transfection with Nogo-B plasmid cancelled that apoptosis induced by siRNogoB in SW480 cells. Besides, combinatory treatment with siR-Nogo-B/staurosporine (STS) or siR-Nogo-B/Fas ligand (FasL) synergistically reduced cell viability and increased the expression of apoptotic signaling proteins in colorectal cancer cells. These results strongly support our contention that Nogo-B most likely played an oncogenic role in colorectal cancer cells, mainly by negatively regulating the extrinsic apoptotic pathway in them. Finally, we revealed that suppression of Nogo-B caused down-regulation of c-FLIP, known as a major anti-apoptotic protein, and activation of caspase-8 in the death receptor pathway. Interaction between Nogo-B and c-FLIP was shown by immunoprecipitation and immunofluorescence studies. In conclusion, Nogo-B was shown to play an important negative role in apoptotic signaling through its interaction with c-FLIP in colorectal cancer cells, and may thus become a novel therapeutic target for colorectal cancer. Copyright © 2018 Elsevier B.V. All rights reserved.

Developmental block and programmed cell death in Bos indicus embryos: effects of protein supplementation source and developmental kinetics.

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Sheila Merlo Garcia

Full Text Available The aims of this study were to determine if the protein source of the medium influences zebu embryo development and if developmental kinetics, developmental block and programmed cell death are related. The culture medium was supplemented with either fetal calf serum or bovine serum albumin. The embryos were classified as Fast (n = 1,235 or Slow (n = 485 based on the time required to reach the fourth cell cycle (48 h and 90 h post insemination - hpi -, respectively. The Slow group was further separated into two groups: those presenting exactly 4 cells at 48 hpi (Slow/4 cells and those that reached the fourth cell cycle at 90 hpi (Slow. Blastocyst quality, DNA fragmentation, mitochondrial membrane potential and signs of apoptosis or necrosis were evaluated. The Slow group had higher incidence of developmental block than the Fast group. The embryos supplemented with fetal calf serum had lower quality. DNA fragmentation and mitochondrial membrane potential were absent in embryos at 48 hpi but present at 90 hpi. Early signs of apoptosis were more frequent in the Slow and Slow/4 cell groups than in the Fast group. We concluded that fetal calf serum reduces blastocyst development and quality, but the mechanism appears to be independent of DNA fragmentation. The apoptotic cells detected at 48 hpi reveal a possible mechanism of programmed cell death activation prior to genome activation. The apoptotic cells observed in the slow-developing embryos suggested a relationship between programmed cell death and embryonic developmental kinetics in zebu in vitro-produced embryos.

Akebia saponin PA induces autophagic and apoptotic cell death in AGS human gastric cancer cells.

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Xu, Mei-Ying; Lee, Dong Hwa; Joo, Eun Ji; Son, Kun Ho; Kim, Yeong Shik

2013-09-01

In this study, we investigated the anticancer mechanism of akebia saponin PA (AS), a natural product isolated from Dipsacus asperoides in human gastric cancer cell lines. It was shown that AS-induced cell death is caused by autophagy and apoptosis in AGS cells. The apoptosis-inducing effect of AS was characterized by annexin V/propidium (PI) staining, increase of sub-G1 phase and caspase-3 activation, while the autophagy-inducing effect was indicated by the formation of cytoplasmic vacuoles and microtubule-associated protein 1 light chain-3 II (LC3-II) conversion. The autophagy inhibitor bafilomycin A1 (BaF1) decreased AS-induced cell death and caspase-3 activation, but caspase-3 inhibitor Ac-DEVD-CHO did not affect LC3-II accumulation or AS-induced cell viability, suggesting that AS induces autophagic cell death and autophagy contributes to caspase-3-dependent apoptosis. Furthermore, AS activated p38/c-Jun N-terminal kinase (JNK), which could be inhibited by BaF1, and caspase-3 activation was attenuated by both SB202190 and SP600125, indicating that AS-induced autophagy promotes mitogen-activated protein kinases (MAPKs)-mediated apoptosis. Taken together, these results demonstrate that AS induces autophagic and apoptotic cell death and autophagy plays the main role in akebia saponin PA-induced cell death. Copyright © 2013 Elsevier Ltd. All rights reserved.

Membrane Protected Apoptotic Trophoblast Microparticles Contain Nucleic Acids

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Orozco, Aaron F.; Jorgez, Carolina J.; Horne, Cassandra; Marquez-Do, Deborah A.; Chapman, Matthew R.; Rodgers, John R.; Bischoff, Farideh Z.; Lewis, Dorothy E.

2008-01-01

Microparticles (MPs) that circulate in blood may be a source of DNA for molecular analyses, including prenatal genetic diagnoses. Because MPs are heterogeneous in nature, however, further characterization is important before use in clinical settings. One key question is whether DNA is either bound to aggregates of blood proteins and lipid micelles or intrinsically associated with MPs from dying cells. To test the latter hypothesis, we asked whether MPs derived in vitro from dying cells were similar to those in maternal plasma. JEG-3 cells model extravillous trophoblasts, which predominate during the first trimester of pregnancy when prenatal diagnosis is most relevant. MPs were derived from apoptosis and increased over 48 hours. Compared with necrotic MPs, DNA in apoptotic MPs was more fragmented and resistant to plasma DNases. Membrane-specific dyes indicated that apoptotic MPs had more membranous material, which protects nucleic acids, including RNA. Flow cytometry showed that MPs derived from dying cells displayed light scatter and DNA staining similar to MPs found in maternal plasma. Quantification of maternal MPs using characteristics defined by MPs generated in vitro revealed a significant increase of DNA+ MPs in the plasma of women with preeclampsia compared with plasma from women with normal pregnancies. Apoptotic MPs are therefore a likely source of stable DNA that could be enriched for both early genetic diagnosis and monitoring of pathological pregnancies. PMID:18974299

Comparative Antioxidant, Antiproliferative and Apoptotic Effects of ...

African Journals Online (AJOL)

Purpose: To determine and compare the antioxidant, antiproliferative and apoptotic effects of leaf infusions of Ilex laurina ... Both plant infusions inhibited viability and cell growth of SW480 and SW620 cells. .... 100 g of dry extract, from a gallic acid calibration curve [9]. ..... antioxidant capacity and in vitro inhibition of colon.

Pro-apoptotic Effect of Pifithrin-α on Preimplantation Porcine Fertilized Embryo Development

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Brendan Mulligan

2012-12-01

Full Text Available The aim of this study was to investigate the impact of a reported p53 inhibitor, pifithrin-α (PFT-α, on preimplantation porcine in vitro fertilized (IVF embryo development in culture. Treatment of PFT-α was administered at both early (0 to 48 hpi, and later stages (48 to 168 hpi of preimplantation development, and its impact upon the expression of five genes related to apoptosis (p53, bak, bcl-xL, p66Shc and caspase3, was assessed in resulting d 7 blastocysts, using real-time quantitative PCR. Total cell numbers, along with the number of apoptotic nuclei, as detected by the in situ cell death detection assay, were also calculated on d 7 in treated and non-treated control embryos. The results indicate that PFT-α, when administered at both early and later stages of porcine IVF embryo development, increases the incidence of apoptosis in resulting blastocysts. When administered at early cleavage stages, PFT-α treatment was shown to reduce the developmental competence of porcine IVF embryos, as well as reducing the quality of resulting blastocysts in terms of overall cell numbers. In contrast, at later stages, PFT-α administration resulted in marginally increased blastocyst development rates amongst treated embryos, but did not affect cell numbers. However, PFT-α treatment induced apoptosis and apoptotic related gene expression, in all treated embryos, irrespective of the timing of treatment. Our results indicate that PFT-α may severely compromise the developmental potential of porcine IVF embryos, and is a potent apoptotic agent when placed into porcine embryo culture media. Thus, caution should be exercised when using PFT-α as a specific inhibitor of p53 mediated apoptosis, in the context of porcine IVF embryo culture systems.

PKCη confers protection against apoptosis by inhibiting the pro-apoptotic JNK activity in MCF-7 cells

International Nuclear Information System (INIS)

Rotem-Dai, Noa; Oberkovitz, Galia; Abu-Ghanem, Sara; Livneh, Etta

2009-01-01

Apoptosis is frequently regulated by different protein kinases including protein kinase C family enzymes. Both inhibitory and stimulatory effects were demonstrated for several of the different PKC isoforms. Here we show that the novel PKC isoform, PKCη, confers protection against apoptosis induced by the DNA damaging agents, UVC irradiation and the anti-cancer drug - Camptothecin, of the breast epithelial adenocarcinoma MCF-7 cells. The induced expression of PKCη in MCF-7 cells, under the control of the tetracycline-responsive promoter, resulted in increased cell survival and inhibition of cleavage of the apoptotic marker PARP-1. Activation of caspase-7 and 9 and the release of cytochrome c were also inhibited by the inducible expression of PKCη. Furthermore, JNK activity, required for apoptosis in MCF-7, as indicated by the inhibition of both caspase-7 cleavage and cytochrome c release from the mitochondria in the presence of the JNK inhibitor SP600125, was also suppressed by PKCη expression. Hence, in contrast to most PKC isoforms enhancing JNK activation, our studies show that PKCη is an anti-apoptotic protein, acting as a negative regulator of JNK activity. Thus, PKCη could represent a target for intervention aimed to reduce resistance to anti-cancer treatments.

Induction of apoptosis in non-small cell lung carcinoma A549 cells by PGD₂ metabolite, 15d-PGJ₂.

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Wang, Jun-Jie; Mak, Oi-Tong

2011-11-01

PGD2 (prostaglandin D2) is a mediator in various pathophysiological processes, including inflammation and tumorigenesis. PGD2 can be converted into active metabolites and is known to activate two distinct receptors, DP (PGD2 receptor) and CRTH2/DP2 (chemoattractant receptor-homologous molecule expressed on Th2 cells). In the past, PGD2 was thought to be involved principally in the process of inflammation. However, in recent years, several studies have shown that PGD2 has anti-proliferative ability against tumorigenesis and can induce cellular apoptosis via activation of the caspase-dependent pathway in human colorectal cancer cells, leukaemia cells and eosinophils. In the lung, where PGD2 is highly released when sensitized mast cells are challenged with allergen, the mechanism of PGD2-induced apoptosis is unclear. In the present study, A549 cells, a type of NSCLC (non-small cell lung carcinoma), were treated with PGD2 under various conditions, including while blocking DP and CRTH2/DP2 with the selective antagonists BWA868C and ramatroban respectively. We report here that PGD2 induces A549 cell death through the intrinsic apoptotic pathway, although the process does not appear to involve either DP or CRTH2/DP2. Similar results were also found with H2199 cells, another type of NSCLC. We found that PGD2 metabolites induce apoptosis effectively and that 15d-PGJ2 (15-deoxy-Δ12,14-prostaglandin J2) is a likely candidate for the principal apoptotic inducer in PGD2-induced apoptosis in NSCLC A549 cells.

The antiproliferative and apoptotic effects of apigenin on glioblastoma cells.

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Stump, Trevor A; Santee, Brittany N; Williams, Lauren P; Kunze, Rachel A; Heinze, Chelsae E; Huseman, Eric D; Gryka, Rebecca J; Simpson, Denise S; Amos, Samson

2017-07-01

Glioblastoma (GBM) is highly proliferative, infiltrative, malignant and the most deadly form of brain tumour. The epidermal growth factor receptor (EGFR) is overexpressed, amplified and mutated in GBM and has been shown to play key and important roles in the proliferation, growth and survival of this tumour. The goal of our study was to investigate the antiproliferative, apoptotic and molecular effects of apigenin in GBM. Proliferation and viability tests were carried out using the trypan blue exclusion, MTT and lactate dehydrogenase (LDH) assays. Flow cytometry was used to examine the effects of apigenin on the cell cycle check-points. In addition, we determined the effects of apigenin on EGFR-mediated signalling pathways by Western blot analyses. Our results showed that apigenin reduced cell viability and proliferation in a dose- and time-dependent manner while increasing cytotoxicity in GBM cells. Treatment with apigenin-induced is poly ADP-ribose polymerase (PARP) cleavage and caused cell cycle arrest at the G2M checkpoint. Furthermore, our data revealed that apigenin inhibited EGFR-mediated phosphorylation of mitogen-activated protein kinase (MAPK), AKT and mammalian target of rapamycin (mTOR) signalling pathways and attenuated the expression of Bcl-xL. Our results demonstrated that apigenin has potent inhibitory effects on pathways involved in GBM proliferation and survival and could potentially be used as a therapeutic agent for GBM. © 2017 Royal Pharmaceutical Society.

Cell death triggered by alpha-emitting 213Bi-immunoconjugates in HSC45-M2 gastric cancer cells is different from apoptotic cell death

International Nuclear Information System (INIS)

Seidl, Christof; Schroeck, Hedwig; Seidenschwang, Sabine; Beck, Roswitha; Schwaiger, Markus; Senekowitsch-Schmidtke, Reingard; Schmid, Ernst; Abend, Michael; Becker, Karl-Friedrich; Apostolidis, Christos; Nikula, Tuomo K.; Kremmer, Elisabeth

2005-01-01

Radioimmunotherapy with α-particle-emitting nuclides, such as 213 Bi, is a promising concept for the elimination of small tumour nodules or single disseminated tumour cells. The aim of this study was to investigate cellular damage and the mode of cell death triggered by 213 Bi-immunoconjugates. Human gastric cancer cells (HSC45-M2) expressing d9-E-cadherin were incubated with different levels of activity of 213 Bi-d9MAb targeting d9-E-cadherin and 213 Bi-d8MAb, which does not bind to d9-E-cadherin. Micronucleated (M) cells, abnormal (A) cells and apoptotic (A) [(MAA)] cells were scored microscopically in the MAA assay following fluorescent staining of nuclei and cytoplasm. Chromosomal aberrations were analysed microscopically following Giemsa staining. The effect of z-VAD-fmk, known to inhibit apoptosis, on the prevention of cell death was investigated following treatment of HSC45-M2 cells with sorbitol as well as 213 Bi-d9MAb. Activation of caspase 3 after incubation of HSC45-M2 cells with both sorbitol and 213 Bi-d9MAb was analysed via Western blotting. Following incubation of HSC45-M2 human gastric cancer cells expressing d9-E-cadherin with 213 Bi-d9MAb the number of cells killed increased proportional to the applied activity concentration. Microscopically visible effects of α-irradiation of HSC45-M2 cells were formation of micronuclei and severe chromosomal aberrations. Preferential induction of these lesions with specific 213 Bi-d9MAb compared with unspecific 213 Bi-d8MAb (not targeting d9-E-cadherin) was not observed if the number of floating, i.e. unbound 213 Bi-immunoconjugates per cell exceeded 2 x 10 4 , most likely due to intense crossfire. In contrast to sorbitol-induced cell death, cell death triggered by 213 Bi-immunoconjugates was independent of caspase 3 activation and could not be inhibited by z-VAD-fmk, known to suppress the apoptotic pathway. 213 Bi-immunoconjugates seem to induce a mode of cell death different from apoptosis in HSC45-M2 cells

The Putative Role of the Non-Gastric H+/K+-ATPase ATP12A (ATP1AL1 as Anti-Apoptotic Ion Transporter: Effect of the H+/K+ ATPase Inhibitor SCH28080 on Butyrate-Stimulated Myelomonocytic HL-60 Cells

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Martin Jakab

2014-10-01

decrease it over the course of the next 48 h. This effect can be observed in the overall- and non-apoptotic fraction of both untreated and 1 mM butyrate-treated HL-60 cells, but not in 1 mM butyrate-stimulated phosphatidylserine-positive cells. These cells do not shrink from 24 h to 72 h and have finally a higher MCV than untreated cells unless they are exposed to SCH28080. 10 mM butyrate induces apoptosis within 24 h. Conclusion: In summary we show that in HL-60 cells ATP12A is a functionally active H+/K+ ATPase that may counteract events during early apoptosis like intracellular acidosis, loss of intracellular K+ ions and apoptotic volume decrease. Its expression and/or susceptibility to the H+/K+ ATPase inhibitor SCH28080 becomes most evident in cells exposing phosphatidylserine on the outer leaflet of the cell membrane and therefore during early apoptosis.

Systems analysis of apoptotic priming in ovarian cancer identifies vulnerabilities and predictors of drug response.

Science.gov (United States)

Zervantonakis, Ioannis K; Iavarone, Claudia; Chen, Hsing-Yu; Selfors, Laura M; Palakurthi, Sangeetha; Liu, Joyce F; Drapkin, Ronny; Matulonis, Ursula; Leverson, Joel D; Sampath, Deepak; Mills, Gordon B; Brugge, Joan S

2017-08-28

The lack of effective chemotherapies for high-grade serous ovarian cancers (HGS-OvCa) has motivated a search for alternative treatment strategies. Here, we present an unbiased systems-approach to interrogate a panel of 14 well-annotated HGS-OvCa patient-derived xenografts for sensitivity to PI3K and PI3K/mTOR inhibitors and uncover cell death vulnerabilities. Proteomic analysis reveals that PI3K/mTOR inhibition in HGS-OvCa patient-derived xenografts induces both pro-apoptotic and anti-apoptotic signaling responses that limit cell killing, but also primes cells for inhibitors of anti-apoptotic proteins. In-depth quantitative analysis of BCL-2 family proteins and other apoptotic regulators, together with computational modeling and selective anti-apoptotic protein inhibitors, uncovers new mechanistic details about apoptotic regulators that are predictive of drug sensitivity (BIM, caspase-3, BCL-X L ) and resistance (MCL-1, XIAP). Our systems-approach presents a strategy for systematic analysis of the mechanisms that limit effective tumor cell killing and the identification of apoptotic vulnerabilities to overcome drug resistance in ovarian and other cancers.High-grade serous ovarian cancers (HGS-OvCa) frequently develop chemotherapy resistance. Here, the authors through a systematic analysis of proteomic and drug response data of 14 HGS-OvCa PDXs demonstrate that targeting apoptosis regulators can improve response of these tumors to inhibitors of the PI3K/mTOR pathway.

Synergistic effect of aluminum and ionizing radiation upon ultrastructure, oxidative stress and apoptotic alterations in Paneth cells of rat intestine.

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Eltahawy, N A; Elsonbaty, S M; Abunour, S; Zahran, W E

2017-03-01

Environmental and occupational exposure to aluminum along with ionizing radiation results in serious health problems. This study was planned to investigate the impact of oxidative stress provoked by exposure to ionizing radiation with aluminum administration upon cellular ultra structure and apoptotic changes in Paneth cells of rat small intestine . Animals received daily aluminum chloride by gastric gavage at a dose 0.5 mg/Kg BW for 4 weeks. Whole body gamma irradiation was applied at a dose 2 Gy/week up to 8 Gy. Ileum malondialdehyde, advanced oxidative protein products, protein carbonyl and tumor necrosis factor-alpha were assessed as biomarkers of lipid peroxidation, protein oxidation and inflammation respectively along with superoxide dismutase, catalase, and glutathione peroxidase activities as enzymatic antioxidants. Moreover, analyses of cell cycle division and apoptotic changes were evaluated by flow cytometry. Intestinal cellular ultra structure was investigated using transmission electron microscope.Oxidative and inflammatory stresses assessment in the ileum of rats revealed that aluminum and ionizing radiation exposures exhibited a significant effect upon the increase in oxidative stress biomarkers along with the inflammatory marker tumor necrosis factor-α accompanied by a significant decreases in the antioxidant enzyme activities. Flow cytometric analyses showed significant alterations in the percentage of cells during cell cycle division phases along with significant increase in apoptotic cells. Ultra structurally, intestinal cellular alterations with marked injury in Paneth cells at the sites of bacterial translocation in the crypt of lumens were recorded. The results of this study have clearly showed that aluminum and ionizing radiation exposures induced apoptosis with oxidative and inflammatory disturbance in the Paneth cells of rat intestine, which appeared to play a major role in the pathogenesis of cellular damage. Furthermore, the

Comparative analysis of programmed cell death pathways in filamentous fungi

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Wortman Jennifer R

2005-12-01

Full Text Available Abstract Background Fungi can undergo autophagic- or apoptotic-type programmed cell death (PCD on exposure to antifungal agents, developmental signals, and stress factors. Filamentous fungi can also exhibit a form of cell death called heterokaryon incompatibility (HI triggered by fusion between two genetically incompatible individuals. With the availability of recently sequenced genomes of Aspergillus fumigatus and several related species, we were able to define putative components of fungi-specific death pathways and the ancestral core apoptotic machinery shared by all fungi and metazoa. Results Phylogenetic profiling of HI-associated proteins from four Aspergilli and seven other fungal species revealed lineage-specific protein families, orphan genes, and core genes conserved across all fungi and metazoa. The Aspergilli-specific domain architectures include NACHT family NTPases, which may function as key integrators of stress and nutrient availability signals. They are often found fused to putative effector domains such as Pfs, SesB/LipA, and a newly identified domain, HET-s/LopB. Many putative HI inducers and mediators are specific to filamentous fungi and not found in unicellular yeasts. In addition to their role in HI, several of them appear to be involved in regulation of cell cycle, development and sexual differentiation. Finally, the Aspergilli possess many putative downstream components of the mammalian apoptotic machinery including several proteins not found in the model yeast, Saccharomyces cerevisiae. Conclusion Our analysis identified more than 100 putative PCD associated genes in the Aspergilli, which may help expand the range of currently available treatments for aspergillosis and other invasive fungal diseases. The list includes species-specific protein families as well as conserved core components of the ancestral PCD machinery shared by fungi and metazoa.

Esculetin exerts anti-proliferative effects against non-small-cell lung carcinoma by suppressing specificity protein 1 in vitro.

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Lee, Ra H; Jeon, Young-Joo; Cho, Jin H; Jang, Jeong-Yun; Kong, Il-Keun; Kim, Seok-Ho; Kim, MinSeok S; Chung, Hak-Jae; Oh, Keon B; Park, Seon-Min; Shin, Jae-Cheon; Seo, Jae-Min; Ko, Sungho; Shim, Jung-Hyun; Chae, Jung-Il

2017-01-01

Esculetin, a coumarin derivative, is a phenolic compound isolated from Artemisia capillaris, Citrus limonia, and Euphorbia lathyris. Although it has been reported to have anti-inflammatory, anti-oxidant, and anti-proliferative activities in several human cancers, its anti-proliferative activity against non-small-cell lung carcinoma (NSCLC) and the molecular mechanisms involved have not been adequately elucidated. In this study, we used two NSCLC cell lines (NCI-H358 and NCI-H1299) to investigate the anti-proliferative activity and apoptotic effect of esculetin. Our data showed that esculetin-treated cells exhibited reduced proliferation and apoptotic cell morphologies. Intriguingly, the transcription factor specificity protein 1 (Sp1) was significantly suppressed by esculetin in a dose- and time-dependent manner. Furthermore, the levels of p27 and p21, two key regulators of the cell cycle, were up-regulated by the esculetin-mediated down-regulation of Sp1; the level of a third cell-cycle regulator, survivin, was decreased, resulting in caspase-dependent apoptosis. Therefore, we conclude that esculetin could be a potent anti-proliferative agent in patients with NSCLC.

The anti-apoptotic members of the Bcl-2 family are attractive tumor-associated antigens

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Straten, Per thor; Andersen, Mads Hald; Andersen, Mads Hald

2010-01-01

Anti-apoptotic members of the Bcl-2 family (Bcl-2, Bcl-X(L) and Mcl-2) are pivotal regulators of apoptotic cell death. They are all highly overexpressed in cancers of different origin in which they enhance the survival of the cancer cells. Consequently, they represent prime candidates for anti-ca...

Induction of apoptotic death and retardation of neuronal differentiation of human neural stem cells by sodium arsenite treatment

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Ivanov, Vladimir N., E-mail: vni3@columbia.edu [Center for Radiological Research, Department of Radiation Oncology, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, NY 10032 (United States); Hei, Tom K. [Center for Radiological Research, Department of Radiation Oncology, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, NY 10032 (United States)

2013-04-01

Chronic arsenic toxicity is a global health problem that affects more than 100 million people worldwide. Long-term health effects of inorganic sodium arsenite in drinking water may result in skin, lung and liver cancers and in severe neurological abnormalities. We investigated in the present study whether sodium arsenite affects signaling pathways that control cell survival, proliferation and neuronal differentiation of human neural stem cells (NSC). We demonstrated that the critical signaling pathway, which was suppressed by sodium arsenite in NSC, was the protective PI3K–AKT pathway. Sodium arsenite (2–4 μM) also caused down-regulation of Nanog, one of the key transcription factors that control pluripotency and self-renewal of stem cells. Mitochondrial damage and cytochrome-c release induced by sodium arsenite exposure was followed by initiation of the mitochondrial apoptotic pathway in NSC. Beside caspase-9 and caspase-3 inhibitors, suppression of JNK activity decreased levels of arsenite-induced apoptosis in NSC. Neuronal differentiation of NSC was substantially inhibited by sodium arsenite exposure. Overactivation of JNK1 and ERK1/2 and down-regulation of PI3K–AKT activity induced by sodium arsenite were critical factors that strongly affected neuronal differentiation. In conclusion, sodium arsenite exposure of human NSC induces the mitochondrial apoptotic pathway, which is substantially accelerated due to the simultaneous suppression of PI3K–AKT. Sodium arsenite also negatively affects neuronal differentiation of NSC through overactivation of MEK–ERK and suppression of PI3K–AKT. - Highlights: ► Arsenite induces the mitochondrial apoptotic pathway in human neural stem cells. ► Arsenite-induced apoptosis is strongly upregulated by suppression of PI3K–AKT. ► Arsenite-induced apoptosis is strongly down-regulated by inhibition of JNK–cJun. ► Arsenite negatively affects neuronal differentiation by inhibition of PI3K–AKT.

Induction of apoptotic death and retardation of neuronal differentiation of human neural stem cells by sodium arsenite treatment

International Nuclear Information System (INIS)

Ivanov, Vladimir N.; Hei, Tom K.

2013-01-01

Chronic arsenic toxicity is a global health problem that affects more than 100 million people worldwide. Long-term health effects of inorganic sodium arsenite in drinking water may result in skin, lung and liver cancers and in severe neurological abnormalities. We investigated in the present study whether sodium arsenite affects signaling pathways that control cell survival, proliferation and neuronal differentiation of human neural stem cells (NSC). We demonstrated that the critical signaling pathway, which was suppressed by sodium arsenite in NSC, was the protective PI3K–AKT pathway. Sodium arsenite (2–4 μM) also caused down-regulation of Nanog, one of the key transcription factors that control pluripotency and self-renewal of stem cells. Mitochondrial damage and cytochrome-c release induced by sodium arsenite exposure was followed by initiation of the mitochondrial apoptotic pathway in NSC. Beside caspase-9 and caspase-3 inhibitors, suppression of JNK activity decreased levels of arsenite-induced apoptosis in NSC. Neuronal differentiation of NSC was substantially inhibited by sodium arsenite exposure. Overactivation of JNK1 and ERK1/2 and down-regulation of PI3K–AKT activity induced by sodium arsenite were critical factors that strongly affected neuronal differentiation. In conclusion, sodium arsenite exposure of human NSC induces the mitochondrial apoptotic pathway, which is substantially accelerated due to the simultaneous suppression of PI3K–AKT. Sodium arsenite also negatively affects neuronal differentiation of NSC through overactivation of MEK–ERK and suppression of PI3K–AKT. - Highlights: ► Arsenite induces the mitochondrial apoptotic pathway in human neural stem cells. ► Arsenite-induced apoptosis is strongly upregulated by suppression of PI3K–AKT. ► Arsenite-induced apoptosis is strongly down-regulated by inhibition of JNK–cJun. ► Arsenite negatively affects neuronal differentiation by inhibition of PI3K–AKT

Adoptive Transfer of Dying Cells Causes Bystander-Induced Apoptosis

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Schwulst, Steven J.; Davis, Christopher G.; Coopersmith, Craig M.; Hotchkiss, Richard S.

2009-01-01

The anti-apoptotic Bcl-2 protein has the remarkable ability to prevent cell death from several noxious stimuli. Intriguingly, Bcl-2 overexpression in one cell type has been reported to protect against cell death in neighboring non-Bcl-2 overexpressing cell types. The mechanism of this “trans” protection has been speculated to be secondary to the release of a cytoprotective factor by Bcl-2 overexpressing cells. We employed a series of adoptive transfer experiments in which lymphocytes that overexpress Bcl-2 were administered to either wild type mice or mice lacking mature T and B cells (Rag-1-/-) to detect the presence or absence of the putative protective factor. We were unable to demonstrate “trans” protection. However, adoptive transfer of apoptotic or necrotic cells exacerbated the degree of apoptotic death in neighboring non-Bcl-2 overexpressing cells (p≤0.05). Therefore, this data suggests that dying cells emit signals triggering cell death in neighboring non-Bcl-2 overexpressing cells, i.e. a “trans” destructive effect. PMID:17194455

Three-dimensional apoptotic nuclear behavior analyzed by means of Field Emission in Lens Scanning Electron Microscope

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S. Salucci

2015-09-01

Full Text Available Apoptosis is an essential biological function required during embryogenesis, tissue homeostasis, organ development and immune system regulation. It is an active cell death pathway involved in a variety of pathological conditions. During this process cytoskeletal proteins appear damaged and undergo an enzymatic disassembling, leading to formation of apoptotic features. This study was designed to examine the three-dimensional chromatin behavior and cytoskeleton involvement, in particular actin re-modeling. HL-60 cells, exposed to hyperthermia, a known apoptotic trigger, were examined by means of a Field Emission in Lens Scanning Electron Microscope (FEISEM. Ultrastructural observations revealed in treated cells the presence of apoptotic patterns after hyperthermia trigger. In particular, three-dimensional apoptotic chromatin rearrangements appeared involving the translocation of filamentous actin from cytoplasm to the nucleus. FEISEM immunogold techniques showed actin labeling and its precise three-dimensional localization in the diffuse chromatin, well separated from the condensed one. The actin presence in dispersed chromatin inside the apoptotic nucleus can be considered an important feature, indispensable to permit the apoptotic machinery evolution.

The non-death role of metacaspase proteases

International Nuclear Information System (INIS)

Shrestha, Amit; Megeney, Lynn A.

2012-01-01

The activation of caspase proteases and the targeting of protein substrates act as key steps in the engagement and conduct of apoptosis/programmed cell death. However, the discovery of caspase involvement in diverse non-apoptotic cellular functions strongly suggests that these proteins may have evolved from a core behavior unrelated to the induction of cell death. The presence of similar proteases, termed metacaspases, in single cell organisms supports the contention that such proteins may have co-evolved or derived from a critical non-death function. Indeed, the benefit(s) for single cell life forms to retain proteins solely dedicated to self destruction would be countered by a strong selection pressure to curb or eliminate such processes. Examination of metacaspase biology provides evidence that these ancient protease forerunners of the caspase family also retain versatility in function, i.e., death and non-death cell functions. Here, we provide a critical review that highlights the non-death roles of metacaspases that have been described thus far, and the impact that these observations have for our understanding of the evolution and cellular utility of this protease family.

Metformin combined with aspirin significantly inhibit pancreatic cancer cell growth in vitro and in vivo by suppressing anti-apoptotic proteins Mcl-1 and Bcl-2

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Yue, Wen; Zheng, Xi; Lin, Yong; Yang, Chung S.; Xu, Qing; Carpizo, Darren; Huang, Huarong; DiPaola, Robert S.; Tan, Xiang-Lin

2015-01-01

Metformin and aspirin have been studied extensively as cancer preventive or therapeutic agents. However, the effects of their combination on pancreatic cancer cells have not been investigated. Herein, we evaluated the effects of metformin and aspirin, alone or in combination, on cell viability, migration, and apoptosis as well as the molecular changes in mTOR, STAT3 and apoptotic signaling pathways in PANC-1 and BxPC3 cells. Metformin and aspirin, at relatively low concentrations, demonstrated synergistically inhibitory effects on cell viability. Compared to the untreated control or individual drug, the combination of metformin and aspirin significantly inhibited cell migration and colony formation of both PANC-1 and BxPC-3 cells. Metformin combined with aspirin significantly inhibited the phosphorylation of mTOR and STAT3, and induced apoptosis as measured by caspase-3 and PARP cleavage. Remarkably, metformin combined with aspirin significantly downregulated the anti-apoptotic proteins Mcl-1 and Bcl-2, and upregulated the pro-apoptotic proteins Bim and Puma, as well as interrupted their interactions. The downregulation of Mcl-1 and Bcl-2 was independent of AMPK or STAT3 pathway but partially through mTOR signaling and proteasome degradation. In a PANC-1 xenograft mouse model, we demonstrated that the combination of metformin and aspirin significantly inhibited tumor growth and downregulated the protein expression of Mcl-1 and Bcl-2 in tumors. Taken together, the combination of metformin and aspirin significantly inhibited pancreatic cancer cell growth in vitro and in vivo by regulating the pro- and anti-apoptotic Bcl-2 family members, supporting the continued investigation of this two drug combination as chemopreventive or chemotherapeutic agents for pancreatic cancer. PMID:26056043

Different immunophenotypical apoptotic profiles characterise megakaryocytes of essential thrombocythaemia and primary myelofibrosis.

Science.gov (United States)

Florena, A M; Tripodo, C; Di Bernardo, A; Iannitto, E; Guarnotta, C; Porcasi, R; Ingrao, S; Abbadessa, V; Franco, V

2009-04-01

Essential thrombocythaemia (ET) and primary myelofibrosis (PMF) share some clinical and pathological features, but show different biological behaviour and prognosis. The latest contributions to understanding the nature of these disorders have focused on bone marrow microenvironment remodelling and proliferative stress, recognising megakaryocytes (MKCs) as "key-cells". The aim of this study was to investigate the apoptotic profile of ET and PMF MKCs in order to further characterise the biology of these disorders. Bone marrow biopsy samples from 30 patients with ET, and 30 patients with PMF, were immunophenotypically studied for the expression of pro-apoptotic (Fas, Fas-L, Bax, Bad) and anti-apoptotic (Bcl-2, Bcl-XL, hTERT (human telomerase reverse transcriptase)) molecules and the "executioner" molecule caspase-3. The fraction of MKCs undergoing apoptosis was assessed by deoxynucleotidyl transferase-mediated dUTP nick-end labelling. Only the mitochondrial pathway seemed to be involved in MKC apoptosis. The anti-apoptotic molecule Bcl-XL was predominantly found in ET MKCs (50.5% of ET MKCs versus 35% of PMF MKCs; p = 0.036), while pro-apoptotic molecules Bax and Bad showed a prevalent expression in PMF MKCs (30.5% of ET MKCs versus 55% of PMF MKCs; 41% of ET MKCs versus 52% of PMF MKCs; p = 0.001 and p = 0.068, respectively). A significant fraction of PMF MKCs were committed to apoptosis according to caspase-3 expression and TUNEL, while only few ET cells were committed to apoptosis. hTERT was significantly more expressed in PMF (32% of ET MKCs versus 46% of PMF MKCs; p = 0.022), in agreement with the proliferative nature of this disease. It was found that ET and PMF MKCs, which barely differ in terms of morphology and aggregation, are characterised by markedly different apoptotic profiles. The rather high apoptotic fraction of PMF was able to support the fibrotic nature of this process, while the anti-apoptotic profile of ET cells fits well with their "steady

A shift to organismal stress resistance in programmed cell death mutants.

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Meredith E Judy

Full Text Available Animals have many ways of protecting themselves against stress; for example, they can induce animal-wide, stress-protective pathways and they can kill damaged cells via apoptosis. We have discovered an unexpected regulatory relationship between these two types of stress responses. We find that C. elegans mutations blocking the normal course of programmed cell death and clearance confer animal-wide resistance to a specific set of environmental stressors; namely, ER, heat and osmotic stress. Remarkably, this pattern of stress resistance is induced by mutations that affect cell death in different ways, including ced-3 (cell death defective mutations, which block programmed cell death, ced-1 and ced-2 mutations, which prevent the engulfment of dying cells, and progranulin (pgrn-1 mutations, which accelerate the clearance of apoptotic cells. Stress resistance conferred by ced and pgrn-1 mutations is not additive and these mutants share altered patterns of gene expression, suggesting that they may act within the same pathway to achieve stress resistance. Together, our findings demonstrate that programmed cell death effectors influence the degree to which C. elegans tolerates environmental stress. While the mechanism is not entirely clear, it is intriguing that animals lacking the ability to efficiently and correctly remove dying cells should switch to a more global animal-wide system of stress resistance.

Andrographolide potentiates the antitumor effect of topotecan in acute myeloid leukemia cells through an intrinsic apoptotic pathway.

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Hodroj, Mohammad Hassan; Jardaly, Achraf; Abi Raad, Sarah; Zouein, Annalise; Rizk, Sandra

2018-01-01

Topotecan (TP) is an anticancer drug acting as topoisomerase I inhibitor that is used in the treatment of many types of cancers including leukemia, but it has significant side effects. Andrographolide, a compound extracted from Andrographis paniculata , was recently proven to inhibit the growth of cancer cells and can induce apoptosis. The aim of this study is to investigate the possible synergism between TP and andrographolide in acute myeloid cells in vitro. U937 acute myeloid leukemic cells were cultured using Roswell Park Memorial Institute (RPMI) medium and then treated for 24 h with TP and andrographolide prepared through the dilution of dimethyl sulfoxide (DMSO) stocks with RPMI on the day of treatment. Cell proliferation was assessed using cell proliferation assay upon treatment with both compounds separately and in combination. Cell-cycle study and apoptosis detection were performed by staining the cells with propidium iodide (PI) stain and Annexin V/PI stain, respectively, followed by flow cytometry analysis. Western blotting was used to assess the expression of various proteins involved in apoptotic pathways. Both TP and andrographolide showed an antiproliferative effect in a dose-dependent manner when applied on U937 cells separately; however, pretreating the cells with andrographolide before applying TP exhibited a synergistic effect with lower inhibitory concentrations (half-maximal inhibitory concentration). Treating the cells with TP alone led to specific cell-cycle arrest at S phase that was more prominent upon pretreatment combination with andrographolide. Using Annexin V/PI staining to assess the proapoptotic effect following the pretreatment combination showed an increase in the number of apoptotic cells, which was supported by the Western blot results that manifested an upregulation of several proapoptotic proteins expression. The pretreatment of U937 with andrographolide followed by low doses of TP showed an enhancement in inducing apoptosis

In vitro apoptotic effects of methanol extracts of Dianthus chinensis and Acalypha australis L. targeting specificity protein 1 in human oral cancer cells.

Science.gov (United States)

Shin, Ji-Ae; Kim, Jae-Jin; Choi, Eun-Sun; Shim, Jung-Hyun; Ryu, Mi Heon; Kwon, Ki Han; Park, Hee-Min; Seo, Jin-Young; Lee, Soo-Yeon; Lim, Do-Won; Cho, Nam-Pyo; Cho, Sung-Dae

2013-07-01

The aims of this study were to evaluate the apoptotic activities and molecular mechanisms of methanol extracts of Dianthus chinensis (MEDC) and Acalypha australis L. (MEAL) in human oral cancer cells. The apoptotic effects and related molecular mechanisms of MEDC and MEAL on oral cancer cells were evaluated using MTS assay, DAPI staining, immunostaining, Western blotting, and reverse transcriptase-polymerase chain reaction. Sp1 was overexpressed in oral tumor tissues compared with normal oral mucosa. Downregulation of Sp1 inhibited the growth of SCC-15 and YD-15 oral cancer cells. MEDC and MEAL inhibited cell growth and induced apoptosis in both cell lines by decreasing the expression of Sp1. In addition, treatment of cells with MEDC and MEAL decreased Mcl-1 expression, which is a downstream target of Sp1. Our results indicate that MEDC and MEAL are bioactive natural products that can potentially induce apoptosis of tumor cells that overexpress the Sp1 protein. Copyright © 2012 Wiley Periodicals, Inc.

Developmental Programming: Impact of Prenatal Testosterone Excess on Ovarian Cell Proliferation and Apoptotic Factors in Sheep1

OpenAIRE

Salvetti, Natalia R.; Ortega, Hugo H.; Veiga-Lopez, Almudena; Padmanabhan, Vasantha

2012-01-01

Prenatal testosterone (T) excess leads to reproductive dysfunctions in sheep, which include increased ovarian follicular recruitment and persistence. To test the hypothesis that follicular disruptions in T sheep stem from changes in the developmental ontogeny of ovarian proliferation and apoptotic factors, pregnant Suffolk sheep were injected twice weekly with T propionate or dihydrotestosterone propionate (DHT; a nonaromatizable androgen) from Days 30 to 90 of gestation. Changes in developme...

Apoptotic potential of two Caryophyllaceae species in MCF-7 and MDA-MB-468 cell lines

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M. Mosaddegh

2018-01-01

Full Text Available Background and objectives: Plants have been used to treat diseases like cancer for many years and today the trend towards their use is increasing. One of the most effective mechanisms of plants against cancer is inducing apoptosis. Apoptosis is a programmed cell death which acts opposite to cell division. It starts in response to some stimuli. Despite the effectiveness of apoptosis inducing agents, their use has been limited due to side effects and resistance to these treatments; so, applying medicinal herbs due to their lower cost and toxicity has drawn attentions. Recent research at the Traditional Medicine and Materia Medica Research Center, Shahid Beheshti University of Medical Sciences on two medicinal plants Acanthophyllum bracteatum and A. microcephalum has shown cytotoxic effects of these two species, but the mechanism of their toxicity has remained unknown; thus, the present study was designed to evaluate the apoptotic potential of Acanthophyllum bracteatum and A. microcephalum. Methods: In the present study, the cytotoxic effects of the methanol extract of Acanthophyllum bracteatum and A. microcephalum was evaluated against MCF-7 and MDA-MB-468 cells by MTT assay; furthermore, their apoptosis potential has been evaluated by annexin-V/propidium iodide assay and Hoechst 33258 staining in the same cell lines. Results: The methanol extract of A. microcephalum and A. bracteatum showed cytotoxic effects against MCF-7 and MDA-MB-468 cell lines with IC50 values of 64, 159 and 102, 250 μg/mL, respectively. The results of the apoptosis assays confirmed the potential of the two plants extracts to induce apoptosis in both cell lines while A. microcephalum demonstrated more considerable results. Conclusion: A. microcephalum could be a suitable choice for further breast cancer studies.

Evaluation of chemical composition, antioxidant, antibacterial, cytotoxic and apoptotic effects of Aloysia citrodora extract on colon cancer cell line

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Amir Mirzaie

2016-06-01

Full Text Available Background: Aloysia citrodora belongs to the Verbenaceae family of plants, a well-known herbal medicine in Iran. The aim of the present study was to investigate the chemical composition, antioxidant, antibacterial, cytotoxic and apoptotic effect of A. citrodora extract against human colon cancer (HT29 cells by using real-time polymerase chain reaction and flow-cytometry methods. Methods: This experimental study was carried out in Islamic Azad University, East Tehran Branch, from March to September of 2014. At first, the A. citrodora chemical constituents were analyzed by gas chromatography-mass spectrometry (GC-MS technique. In addition, antioxidant assay, antibacterial and anti-cancer effect was performed using 1,1-diphenyl-2-picrylhydrazyl (DPPH, disk diffusion and 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT methods, respectively. The half maximal inhibitory concentration (IC50 value was calculated. We extracted total RNA molecules by using RNX solution, after which cDNA was synthesized. Finally, the pro-apoptotic (Bax and anti-apoptotic (Bcl2 gene expression was performed by real-time polymerase chain reaction and apoptotic effects were analyzed using Flow-cytometry method. Results: GC-MS analysis of Aloysia citrodora extract was shown 37 major components and the most frequent component was belonged to Spathulenol (17.57% and Caryophyllene oxide (15.15% The antioxidant activity of the extract was IC50= 0.6±0.03 mg/ml. The maximum and minimum antibacterial effects of extract were belonged to gram-negative and gram-positive bacteria, respectively. Cytotoxic results revealed that the A.citrodora extract have IC50= 20.1±0.78 mg/ml against colon cancer (HT29 cell line and real-time polymerase chain reaction results showed the expression level of Bax and Bcl2 was increased and decreased respectively in colon cancer cell line (3.470±0.72 (P< 0.05, 0.43±0.35 (P< 0.05. In addition, the flow-cytometry results indicated the 38

Cell death triggered by alpha-emitting {sup 213}Bi-immunoconjugates in HSC45-M2 gastric cancer cells is different from apoptotic cell death

Energy Technology Data Exchange (ETDEWEB)

Seidl, Christof; Schroeck, Hedwig; Seidenschwang, Sabine; Beck, Roswitha; Schwaiger, Markus; Senekowitsch-Schmidtke, Reingard [Technische Universitaet Muenchen, Department of Nuclear Medicine, Munich (Germany); Schmid, Ernst [National Research Center for Environment and Health, Institute of Radiation Biology, GSF, Neuherberg (Germany); Abend, Michael [German Armed Forces, Institute of Radiobiology, Munich (Germany); Becker, Karl-Friedrich [Technische Universitaet Muenchen, Institute of Pathology, Munich (Germany); National Research Center for Environment and Health, Institute of Pathology, GSF, Neuherberg (Germany); National Research Center for Environment and Health, Institute of Molecular Immunology, GSF, Munich (Germany); Apostolidis, Christos; Nikula, Tuomo K. [European Commission, Institute for Transuranium Elements, Karlsruhe (Germany); Kremmer, Elisabeth [National Research Center for Environment and Health, Institute of Molecular Immunology, GSF, Munich (Germany)

2005-03-01

Radioimmunotherapy with {alpha}-particle-emitting nuclides, such as{sup 213}Bi, is a promising concept for the elimination of small tumour nodules or single disseminated tumour cells. The aim of this study was to investigate cellular damage and the mode of cell death triggered by {sup 213}Bi-immunoconjugates. Human gastric cancer cells (HSC45-M2) expressing d9-E-cadherin were incubated with different levels of activity of {sup 213}Bi-d9MAb targeting d9-E-cadherin and {sup 213}Bi-d8MAb, which does not bind to d9-E-cadherin. Micronucleated (M) cells, abnormal (A) cells and apoptotic (A) [(MAA)] cells were scored microscopically in the MAA assay following fluorescent staining of nuclei and cytoplasm. Chromosomal aberrations were analysed microscopically following Giemsa staining. The effect of z-VAD-fmk, known to inhibit apoptosis, on the prevention of cell death was investigated following treatment of HSC45-M2 cells with sorbitol as well as {sup 213}Bi-d9MAb. Activation of caspase 3 after incubation of HSC45-M2 cells with both sorbitol and {sup 213}Bi-d9MAb was analysed via Western blotting. Following incubation of HSC45-M2 human gastric cancer cells expressing d9-E-cadherin with {sup 213}Bi-d9MAb the number of cells killed increased proportional to the applied activity concentration. Microscopically visible effects of {alpha}-irradiation of HSC45-M2 cells were formation of micronuclei and severe chromosomal aberrations. Preferential induction of these lesions with specific {sup 213}Bi-d9MAb compared with unspecific {sup 213}Bi-d8MAb (not targeting d9-E-cadherin) was not observed if the number of floating, i.e. unbound {sup 213}Bi-immunoconjugates per cell exceeded 2 x 10{sup 4}, most likely due to intense crossfire. In contrast to sorbitol-induced cell death, cell death triggered by {sup 213}Bi-immunoconjugates was independent of caspase 3 activation and could not be inhibited by z-VAD-fmk, known to suppress the apoptotic pathway. {sup 213}Bi-immunoconjugates seem

Signaling mechanisms of apoptosis-like programmed cell death in unicellular eukaryotes.

Science.gov (United States)

Shemarova, Irina V

2010-04-01

In unicellular eukaryotes, apoptosis-like cell death occurs during development, aging and reproduction, and can be induced by environmental stresses and exposure to toxic agents. The essence of the apoptotic machinery in unicellular organisms is similar to that in mammals, but the apoptotic signal network is less complex and of more ancient origin. The review summarizes current data about key apoptotic proteins and mechanisms of the transduction of apoptotic signals by caspase-like proteases and mitochondrial apoptogenic proteins in unicellular eukaryotes. The roles of receptor-dependent and receptor-independent caspase cascades are reviewed. 2010 Elsevier Inc. All rights reserved.

Caffeine-Induced Premature Chromosome Condensation Results in the Apoptosis-Like Programmed Cell Death in Root Meristems of Vicia faba.

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Dorota Rybaczek

Full Text Available We have demonstrated that the activation of apoptosis-like programmed cell death (AL-PCD was a secondary result of caffeine (CF induced premature chromosome condensation (PCC in hydroxyurea-synchronized Vicia faba root meristem cells. Initiation of the apoptotic-like cell degradation pathway seemed to be the result of DNA damage generated by treatment with hydroxyurea (HU [double-stranded breaks (DSBs mostly] and co-treatment with HU/CF [single-stranded breaks (SSBs mainly]. A single chromosome comet assay was successfully used to study different types of DNA damage (neutral variant-DSBs versus alkaline-DSBs or SSBs. The immunocytochemical detection of H2AXS139Ph and PARP-2 were used as markers for DSBs and SSBs, respectively. Acridine orange and ethidium bromide (AO/EB were applied for quantitative immunofluorescence measurements of dead, dying and living cells. Apoptotic-type DNA fragmentation and positive TUNEL reaction finally proved that CF triggers AL-PCD in stressed V. faba root meristem cells. In addition, the results obtained under transmission electron microscopy (TEM further revealed apoptotic-like features at the ultrastructural level of PCC-type cells: (i extensive vacuolization; (ii abnormal chromatin condensation, its marginalization and concomitant degradation; (iii formation of autophagy-like vesicles (iv protoplast shrinkage (v fragmentation of cell nuclei and (vi extensive degeneration of the cells. The results obtained have been discussed with respect to the vacuolar/autolytic type of plant-specific AL-PCD.

Characterization of a serine protease-mediated cell death program activated in human leukemia cells

International Nuclear Information System (INIS)

O'Connell, A.R.; Holohan, C.; Torriglia, A.; Lee, B.F.; Stenson-Cox, C.

2006-01-01

Tightly controlled proteolysis is a defining feature of apoptosis and caspases are critical in this regard. Significant roles for non-caspase proteases in cell death have been highlighted. Staurosporine causes a rapid induction of apoptosis in virtually all mammalian cell types. Numerous studies demonstrate that staurosporine can activate cell death under caspase-inhibiting circumstances. The aim of this study was to investigate the proteolytic mechanisms responsible for cell death under these conditions. To that end, we show that inhibitors of serine proteases can delay cell death in one such system. Furthermore, through profiling of proteolytic activation, we demonstrate, for the first time, that staurosporine activates a chymotrypsin-like serine protease-dependent cell death in HL-60 cells independently, but in parallel with the caspase controlled systems. Features of the serine protease-mediated system include cell shrinkage and apoptotic morphology, regulation of caspase-3, altered nuclear morphology, generation of an endonuclease and DNA degradation. We also demonstrate a staurosporine-induced activation of a putative 16 kDa chymotrypsin-like protein during apoptosis

CXCL12 suppresses cisplatin-induced apoptosis through activation of JAK2/STAT3 signaling in human non-small-cell lung cancer cells

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Wang M

2017-06-01

Full Text Available Meng Wang,1 Tie Lin,2 Yicun Wang,3 Song Gao,4 Zhaoyang Yang,1 Xuan Hong,1 Gongyan Chen1 1Department of Respiratory Medicine, Harbin Medical University Cancer Hospital, 2Department of Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, 3Jilin Provincial Key Laboratory on Molecular and Chemical Genetics, The Second Hospital of Jilin University, Changchun, 4Department of Clinical Oncology, Shengjing Hospital, China Medical University, Shenyang, People’s Republic of China Aims: Poor efficacy of chemotherapy drugs in non-small-cell lung cancer (NSCLC is the key reason for the failure of treatment, but the mechanism of this remains largely unknown. Stromal cell-derived factor 1-alpha (SDF-1α/CXCL12 is a small chemotactic cytokine protein that plays an important role in tumor progression. In this study, we investigated the anti-apoptotic mechanism of the CXCL12/CXCR4 axis in response to cisplatin, a commonly used chemotherapeutic drug, in human lung adenocarcinoma A549 cells.Methods: CXCL12 blocks cisplatin-induced apoptosis in A549, and the results were shown by propidium iodide/annexin V staining in vitro. The mechanism of CXCL12 stimulating phosphorylation of STAT3 through CXCR4/JAK2 was demonstrated by immunofluorescence and Western blotting. The expression of CXCL12 and p-STAT3 in clinical specimens was examined by immunohistochemistry.Results: CXCL12 significantly decreased the ratio of apoptotic cells and stimulation of phospho-signal transducer and activator of transcription (p-STAT-3 in a time-dependent manner through interaction with CXCR4. Among the signaling molecules downstream of CXCR4, the JAK2/STAT3 pathway plays a predominant role in the anti-apoptotic effect of CXCL12. Analysis of clinical specimens revealed that increased CXCL12 and p-STAT3 expression correlates with enhanced lung cancer progression.Conclusion: These data suggest that CXCR4 contributes to CXCL12-mediated anti-apoptosis by activating JAK2

Kefir exhibits anti‑proliferative and pro‑apoptotic effects on colon adenocarcinoma cells with no significant effects on cell migration and invasion.

Science.gov (United States)

Khoury, Nathalie; El-Hayek, Stephany; Tarras, Omayr; El-Sabban, Marwan; El-Sibai, Mirvat; Rizk, Sandra

2014-11-01

Kefir, a fermented milk product, exhibits anti‑tumoral activity in vivo; yet its mechanism of action remains elusive. Recent studies have focused on the mechanism of action of kefir on cancer cells in vitro. The current study aims at examining the effect of kefir on cell survival, proliferation, and motility of colorectal cancer (CRC) cells. Kefir's anti‑cancer potential was tested on CRC cell lines, Caco‑2 and HT‑29, through cytotoxicity, proliferation, and apoptotic assays. The expression of certain genes involved in proliferation and apoptosis was measured using reverse transcriptase‑polymerase chain reaction (RT‑PCR) and western blotting. To assess the effect of kefir on cancer metastasis, wound‑healing and time‑lapse movies, in addition to collagen‑based invasion assay, were used. The results show that cell‑free fractions of kefir exhibit an anti‑proliferative effect on Caco‑2 and HT‑29 cells. Analysis of DNA content by flow cytometry revealed the ability of kefir to induce cell cycle arrest at the G1 phase. Kefir was also found to induce apoptosis, as seen by cell death ELISA. Results from RT‑PCR showed that kefir decreases the expression of transforming growth factor α (TGF‑α); and transforming growth factor‑β1 (TGF‑β1) in HT‑29 cells. Western blotting results revealed an upregulation in Bax:Bcl‑2 ratio, confirming the pro‑apoptotic effect of kefir, and an increase in p53 independent‑p21 expression upon kefir treatment. MMP expression was not altered by kefir treatment. Furthermore, results from time‑lapse motility movies, wound‑healing, and invasion assays showed no effect on the motility of colorectal as well as breast (MCF‑7 and MB‑MDA‑231) cancer cells upon kefir treatment. Our data suggest that kefir is able to inhibit the proliferation and induce apoptosis in HT‑29 and Caco‑2 CRC cells, yet it does not exhibit a significant effect on the motility and invasion of these cells in vitro.

Comparative Antioxidant, Antiproliferative and Apoptotic Effects of ...

African Journals Online (AJOL)

Purpose: To determine and compare the antioxidant, antiproliferative and apoptotic effects of leaf infusions of Ilex laurina and Ilex paraguariensis in colon cancer cells. Methods: Antioxidant activity was determined by ORAC (Oxygen Radical Absorbance Capacity) and FRAP (Ferric Reducing Antioxidant Power). Cytotoxic ...

Androgen receptor in early apoptotic follicles in the porcine ovary at pregnancy.

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Zbigniew Tabarowski

2006-09-01

Full Text Available Localization of androgen receptor (AR was investigated in ovarian follicles developing and undergoing atresia during pregnancy in the pig. Immunohistochemical staining was conducted on ovarian antral follicles isolated on different days of gestation: 10, 18, 32, 50, 70, and 90. Paraffin sections were also subjected to in situ DNA labeling. TUNEL staining revealed the presence of positive follicles on all days of pregnancy but the amount of atretic follicles increased with time. However, even on day 90 of gestation many follicles were normal, with no signs of atresia. In atretic follicles, apoptotic cells were localized predominantly in the granulosa while theca was much less affected. Atretic follicles with many apoptotic cells were negative for AR. Nuclear immunostaining for AR was positive in follicles with limited amount of apoptotic cells. The same relationship was observed in ovarian follicles isolated at various days of pregnancy.

Apoptotic and anti-proliferative effects of all-trans retinoic acid

International Nuclear Information System (INIS)

Zamora, Monica; Ortega, Juan Alberto; Alana, Lide; Vinas, Octavi; Mampel, Teresa

2006-01-01

We examined the apoptotic and anti-proliferative effects of all-trans retinoic acid (atRA) in HeLa cells. Our results demonstrated that HeLa cells were more sensitive to the anti-proliferative effects of atRA than to its apoptotic effects. Furthermore, we demonstrated that caspase inhibition attenuates cell death but does not alter the atRA-dependent reduction in cell proliferation, which suggests that atRA-induced apoptosis is independent of the arrest in cell proliferation. To check whether ANT proteins mediated these atRA effects, we transiently transfected cells with expression vectors encoding for individual ANT (adenine nucleotide translocase 1-3). Our results revealed that ANT1 and ANT3 over-expressing HeLa cells increased their atRA sensitivity. Thus, our results not only demonstrate the different functional activities of ANT isoforms, but also contribute to a better understanding of the properties of atRA as an anti-tumoral agent used in cancer therapy

Exploration of intrinsic and extrinsic apoptotic pathways in zearalenone-treated rat sertoli cells.

Science.gov (United States)

Xu, Ming-Long; Hu, Jin; Guo, Bao-Ping; Niu, Ya-Ru; Xiao, Cheng; Xu, Yin-Xue

2016-12-01

Zearalenone (ZEA) is a nonsteroidal estrogenic mycotoxin produced mainly by Fusarium. ZEA causes reproductive disorders and is both cytotoxic and genotoxic in animals; however, little is known regarding the molecular mechanism(s) leading to ZEA toxicity. Sertoli cells are somatic cells that support the development of spermatogenic cells. The objective of this study was to explore the effects of ZEA on the proliferation, apoptosis, and necrosis of rat Sertoli cells to uncover signaling pathways underlying ZEA cytotoxicity. ZEA reduced the proliferation of rat Sertoli cells in a dose-dependent manner, as indicated by a CCK8 assay, while flow cytometry revealed that ZEA caused both apoptosis and necrosis. Immunoblotting revealed that ZEA treatment increased the ratio of Bax/Bcl-2, as well as the expression of FasL and caspases-3, -8, and -9, in a dose-dependent manner. Collectively, these data suggest that ZEA induced apoptosis and necrosis in rat Sertoli cells via extrinsic and intrinsic apoptotic pathways. This study provides new insights into the molecular mechanisms by which ZEA exhibits cytotoxicity. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1731-1739, 2016. © 2015 Wiley Periodicals, Inc.

Autophagy postpones apoptotic cell death in PRRSV infection through Bad-Beclin1 interaction.

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Zhou, Ao; Li, Shuaifeng; Khan, Faheem Ahmed; Zhang, Shujun

2016-01-01

Autophagy and apoptosis play significant roles in PRRSV infection and replication. However, the interaction between these 2 processes in PRRSV replication is still far from been completely understood. In our studies, the exposure of MARC-145 cells to PRRSV confirmed the activation of autophagy and subsequent induction of apoptosis. The inhibition of autophagy by 3-methyladenine (3-MA) caused a significant increase in PRRSV-induced apoptosis, showing a potential connection between both mechanisms. Moreover, we observed an increase in Bad expression (a pro-apoptotic protein) and Beclin1 (an autophagy regulator) in virus-infected cells up to 36h. Co-immunoprecipitation assays showed the formation of Bad and Beclin1 complex in PRRSV infected cells. Accordingly, Bad co-localized with Beclin1 in MARC-145 infected cells. Knockdown of Beclin1 significantly decreased PRRSV replication and PRRSV-induced autophagy, while Bad silencing resulted in increased autophagy and enhanced viral replication. Furthermore, PRRSV infection phosphorylated Bad (Ser112) to promote cellular survival. These results demonstrate that autophagy can favor PRRSV replication by postponing apoptosis through the formation of a Bad-Beclin1 complex.

Evaluation of the Cytotoxic and Autophagic Effects of Atorvastatin on MCF-7 Breast Cancer Cells

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Tuğba Alarcon Martinez

2018-05-01

Full Text Available Background: Recently, cytotoxic effects of statins on breast cancer cells have been reported. However, the mechanism of anti-proliferative effects is currently unknown. Autophagy is non-apoptotic programmed cell death, which is characterized by degradation of cytoplasmic components and as having a role in cancer pathogenesis. Aims: To investigate the anti-proliferative effects of atorvastatin on MCF-7 human breast adenocarcinoma cells with respect to both autophagy and apoptosis. Study Design: Cell culture study. Methods: Cell viability was analyzed using WST-1 cell proliferation assay. Apoptosis was determined by the TUNEL method, whereas autophagy was assessed by Beclin-1 and LC3B immunofluorescence staining. Ultrastructural analysis of cells was performed by electron microscopy. Results: Atorvastatin reduced MCF-7 cell proliferation in a dose- and time-dependent manner inducing TUNEL-, Beclin-1-, and LC3B-positive cells. Moreover, ultrastructural analysis showed apoptotic, autophagic, and necrotic morphological changes in treatment groups. A statistically significant increase in the apoptotic index was detected with higher concentrations of atorvastatin at 24 h and 48 h (p<0.05. Conclusion: The anti-proliferative effects of atorvastatin on breast cancer cells is mediated by the induction of both apoptosis and autophagy which shows statins as a potential treatment option for breast cancer.

The anti-apoptotic activity associated with phosphatidylinositol transfer protein α activates the MAPK and Akt/PKB pathway

NARCIS (Netherlands)

Schenning, M.; Goedhart, J.; Gadella (jr.), T.W.J.; Avram, D.; Wirtz, K.W.A.; Snoek, G.T.

2008-01-01

The conditioned medium (CM) from mouse NIH3T3 fibroblast cells overexpressing phosphatidylinositol transfer protein α (PI-TPα; SPIα cells) demonstrates an increased anti-apoptotic activity compared with CM from wild type NIH3T3 (wtNIH3T3) cells. As previously shown, the anti-apoptotic activity acts

Antioxidant and apoptotic effects of an aqueous extract of Urtica dioica on the MCF-7 human breast cancer cell line.

Science.gov (United States)

Fattahi, Sadegh; Ardekani, Ali Motevalizadeh; Zabihi, Ebrahim; Abedian, Zeinab; Mostafazadeh, Amrollah; Pourbagher, Roghayeh; Akhavan-Niaki, Haleh

2013-01-01

Breast cancer is the most prevalent cancer and one of the leading causes of death among women in the world. Plants and herbs may play an important role in complementary or alternative treatment. The aim of this study was to evaluate the antioxidant and anti-proliferative potential of Urtica dioica. The anti oxidant activity of an aqueous extract of Urtica dioica leaf was measured by MTT assay and the FRAP method while its anti-proliferative activity on the human breast cancer cell line (MCF-7) and fibroblasts isolated from foreskin tissue was evaluated using MTT assay. Mechanisms leading to apoptosis were also investigated at the molecular level by measuring the amount of anti and pro-apoptotic proteins and at the cellular level by studying DNA fragmentation and annexin V staining by flow cytometry. The aqueous extract of Urtica dioica showed antioxidant effects with a correlation coefficient of r(2)=0.997. Dose-dependent and anti-proliferative effects of the extract were observed only on MCF-7 cells after 72 hrs with an IC50 value of 2 mg/ml. This anti proliferative activity was associated with an increase of apoptosis as demonstrated by DNA fragmentation, the appearance of apoptotic cells in flow cytometry analysis and an increase of the amount of calpain 1, calpastatin, caspase 3, caspase 9, Bax and Bcl-2, all proteins involved in the apoptotic pathway. This is the first time such in vitro antiproliferative effect of aqueous extract of Urtica dioica leaf has been described for a breast cancer cell line. Our findings warrant further research on Urtica dioica as a potential chemotherapeutic agent for breast cancer.

Different features of Vδ2 T and NK cells in fatal and non-fatal human Ebola infections.

Science.gov (United States)

Cimini, Eleonora; Viola, Domenico; Cabeza-Cabrerizo, Mar; Romanelli, Antonella; Tumino, Nicola; Sacchi, Alessandra; Bordoni, Veronica; Casetti, Rita; Turchi, Federica; Martini, Federico; Bore, Joseph A; Koundouno, Fara Raymond; Duraffour, Sophie; Michel, Janine; Holm, Tobias; Zekeng, Elsa Gayle; Cowley, Lauren; Garcia Dorival, Isabel; Doerrbecker, Juliane; Hetzelt, Nicole; Baum, Jonathan H J; Portmann, Jasmine; Wölfel, Roman; Gabriel, Martin; Miranda, Osvaldo; Díaz, Graciliano; Díaz, José E; Fleites, Yoel A; Piñeiro, Carlos A; Castro, Carlos M; Koivogui, Lamine; Magassouba, N'Faly; Diallo, Boubacar; Ruibal, Paula; Oestereich, Lisa; Wozniak, David M; Lüdtke, Anja; Becker-Ziaja, Beate; Capobianchi, Maria R; Ippolito, Giuseppe; Carroll, Miles W; Günther, Stephan; Di Caro, Antonino; Muñoz-Fontela, César; Agrati, Chiara

2017-05-01

Human Ebola infection is characterized by a paralysis of the immune system. A signature of αβ T cells in fatal Ebola infection has been recently proposed, while the involvement of innate immune cells in the protection/pathogenesis of Ebola infection is unknown. Aim of this study was to analyze γδ T and NK cells in patients from the Ebola outbreak of 2014-2015 occurred in West Africa, and to assess their association with the clinical outcome. Nineteen Ebola-infected patients were enrolled at the time of admission to the Ebola Treatment Centre in Guinea. Patients were divided in two groups on the basis of the clinical outcome. The analysis was performed by using multiparametric flow cytometry established by the European Mobile Laboratory in the field. A low frequency of Vδ2 T-cells was observed during Ebola infection, independently from the clinical outcome. Moreover, Vδ2 T-cells from Ebola patients massively expressed CD95 apoptotic marker, suggesting the involvement of apoptotic mechanisms in Vδ2 T-cell loss. Interestingly, Vδ2 T-cells from survivors expressed an effector phenotype and presented a lower expression of the CTLA-4 exhaustion marker than fatalities, suggesting a role of effector Vδ2 T-cells in the protection. Furthermore, patients with fatal Ebola infection were characterized by a lower NK cell frequency than patients with non fatal infection. In particular, both CD56bright and CD56dim NK frequency were very low both in fatal and non fatal infections, while a higher frequency of CD56neg NK cells was associated to non-fatal infections. Finally, NK activation and expression of NKp46 and CD158a were independent from clinical outcome. Altogether, the data suggest that both effector Vδ2 T-cells and NK cells may play a role in the complex network of protective response to EBOV infection. Further studies are required to characterize the protective effector functions of Vδ2 and NK cells.

Different features of Vδ2 T and NK cells in fatal and non-fatal human Ebola infections.

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Eleonora Cimini

2017-05-01

Full Text Available Human Ebola infection is characterized by a paralysis of the immune system. A signature of αβ T cells in fatal Ebola infection has been recently proposed, while the involvement of innate immune cells in the protection/pathogenesis of Ebola infection is unknown. Aim of this study was to analyze γδ T and NK cells in patients from the Ebola outbreak of 2014-2015 occurred in West Africa, and to assess their association with the clinical outcome.Nineteen Ebola-infected patients were enrolled at the time of admission to the Ebola Treatment Centre in Guinea. Patients were divided in two groups on the basis of the clinical outcome. The analysis was performed by using multiparametric flow cytometry established by the European Mobile Laboratory in the field. A low frequency of Vδ2 T-cells was observed during Ebola infection, independently from the clinical outcome. Moreover, Vδ2 T-cells from Ebola patients massively expressed CD95 apoptotic marker, suggesting the involvement of apoptotic mechanisms in Vδ2 T-cell loss. Interestingly, Vδ2 T-cells from survivors expressed an effector phenotype and presented a lower expression of the CTLA-4 exhaustion marker than fatalities, suggesting a role of effector Vδ2 T-cells in the protection. Furthermore, patients with fatal Ebola infection were characterized by a lower NK cell frequency than patients with non fatal infection. In particular, both CD56bright and CD56dim NK frequency were very low both in fatal and non fatal infections, while a higher frequency of CD56neg NK cells was associated to non-fatal infections. Finally, NK activation and expression of NKp46 and CD158a were independent from clinical outcome.Altogether, the data suggest that both effector Vδ2 T-cells and NK cells may play a role in the complex network of protective response to EBOV infection. Further studies are required to characterize the protective effector functions of Vδ2 and NK cells.

Increased expression of Bcl-2 during mucous cell metaplasia induced by endotoxin and ozone

Energy Technology Data Exchange (ETDEWEB)

Tesfaigzi, J.; Ray, L.M.; Hotchkiss, J.A. [Michigan State Univ., East Lansing, MI (United States)] [and others

1995-12-01

Apoptosis or programmed cell death is accompanied by characteristic morphological changes that distinguish apoptosis from other forms of cell death. These changes include DNA fragmentation, chromatin condensation, cell shrinkage, cell surface pseudopodia, and finally the cellular collapse into membrane-enclosed apoptotic bodies which are rapidly engulfed by macrophages or neighboring cells. Although the morphological features of apoptotic cells are well studied, the biochemical events that control apoptosis are not understood. Programmed cell death is triggered by a variety of pathways that are initiated by different stimuli including noxious agents, DNA damage, the activation of TNF receptors, or the withdrawl of growth factors. The central process of programmed cell death involves a cascade of biochemical events that begins with the initiation of a family of cysteine proteases, including the interleukin-1-{Beta}-converting enzyme, CPP-32, and Apopain. The ratio of Bax, a death-inducer gene, to Bcl-2, an apoptosis suppressor gene, determines whether or not the main apoptotic pathyway is blocked. Apoptosis is suppressed if the ratio of Bcl-2/Bax is > 1, and cells undergo apoptosis if the ratio is < 1. The overexpression of Bcl-2 has been shown to block the apoptotic program triggered by a variety of agents. Therefore, Bcl-2 must be involved in blocking the central pathway of the cell death program. In conclusion, this study showed that high levels of Bcl-2 were detected in some mucous cells at specific time points during mucous cell metaplasia, and this expression was reduced at later time points or was absent after remodeling of this epithelium.

Role of the mitochondria in immune-mediated apoptotic death of the human pancreatic β cell line βLox5.

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Yaíma L Lightfoot

Full Text Available Mitochondria are indispensable in the life and death of many types of eukaryotic cells. In pancreatic beta cells, mitochondria play an essential role in the secretion of insulin, a hormone that regulates blood glucose levels. Unregulated blood glucose is a hallmark symptom of diabetes. The onset of Type 1 diabetes is preceded by autoimmune-mediated destruction of beta cells. However, the exact role of mitochondria has not been assessed in beta cell death. In this study, we examine the role of mitochondria in both Fas- and proinflammatory cytokine-mediated destruction of the human beta cell line, βLox5. IFNγ primed βLox5 cells for apoptosis by elevating cell surface Fas. Consequently, βLox5 cells were killed by caspase-dependent apoptosis by agonistic activation of Fas, but only after priming with IFNγ. This beta cell line undergoes both apoptotic and necrotic cell death after incubation with the combination of the proinflammatory cytokines IFNγ and TNFα. Additionally, both caspase-dependent and -independent mechanisms that require proper mitochondrial function are involved. Mitochondrial contributions to βLox5 cell death were analyzed using mitochondrial DNA (mtDNA depleted βLox5 cells, or βLox5 ρ(0 cells. βLox5 ρ(0 cells are not sensitive to IFNγ and TNFα killing, indicating a direct role for the mitochondria in cytokine-induced cell death of the parental cell line. However, βLox5 ρ(0 cells are susceptible to Fas killing, implicating caspase-dependent extrinsic apoptotic death is the mechanism by which these human beta cells die after Fas ligation. These data support the hypothesis that immune mediators kill βLox5 cells by both mitochondrial-dependent intrinsic and caspase-dependent extrinsic pathways.

Macrophage-expressed IFN-β contributes to apoptotic alveolar epithelial cell injury in severe influenza virus pneumonia.

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Katrin Högner

2013-02-01

Full Text Available Influenza viruses (IV cause pneumonia in humans with progression to lung failure and fatal outcome. Dysregulated release of cytokines including type I interferons (IFNs has been attributed a crucial role in immune-mediated pulmonary injury during severe IV infection. Using ex vivo and in vivo IV infection models, we demonstrate that alveolar macrophage (AM-expressed IFN-β significantly contributes to IV-induced alveolar epithelial cell (AEC injury by autocrine induction of the pro-apoptotic factor TNF-related apoptosis-inducing ligand (TRAIL. Of note, TRAIL was highly upregulated in and released from AM of patients with pandemic H1N1 IV-induced acute lung injury. Elucidating the cell-specific underlying signalling pathways revealed that IV infection induced IFN-β release in AM in a protein kinase R- (PKR- and NF-κB-dependent way. Bone marrow chimeric mice lacking these signalling mediators in resident and lung-recruited AM and mice subjected to alveolar neutralization of IFN-β and TRAIL displayed reduced alveolar epithelial cell apoptosis and attenuated lung injury during severe IV pneumonia. Together, we demonstrate that macrophage-released type I IFNs, apart from their well-known anti-viral properties, contribute to IV-induced AEC damage and lung injury by autocrine induction of the pro-apoptotic factor TRAIL. Our data suggest that therapeutic targeting of the macrophage IFN-β-TRAIL axis might represent a promising strategy to attenuate IV-induced acute lung injury.

The Application of Non-Invasive Apoptosis Detection Sensor (NIADS on Histone Deacetylation Inhibitor (HDACi-Induced Breast Cancer Cell Death

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Kai-Wen Hsu

2018-02-01

Full Text Available Breast cancer is the most common malignancy in women and the second leading cause of cancer death in women. Triple negative breast cancer (TNBC subtype is a breast cancer subset without ER (estrogen receptor, PR (progesterone receptor and HER2 (human epidermal growth factor receptor 2 expression, limiting treatment options and presenting a poorer survival rate. Thus, we investigated whether histone deacetylation inhibitor (HDACi could be used as potential anti-cancer therapy on breast cancer cells. In this study, we found TNBC and HER2-enriched breast cancers are extremely sensitive to Panobinostat, Belinostat of HDACi via experiments of cell viability assay, apoptotic marker identification and flow cytometry measurement. On the other hand, we developed a bioluminescence-based live cell non-invasive apoptosis detection sensor (NIADS detection system to evaluate the quantitative and kinetic analyses of apoptotic cell death by HDAC treatment on breast cancer cells. In addition, the use of HDACi may also contribute a synergic anti-cancer effect with co-treatment of chemotherapeutic agent such as doxorubicin on TNBC cells (MDA-MB-231, but not in breast normal epithelia cells (MCF-10A, providing therapeutic benefits against breast tumor in the clinic.

Non-apoptotic functions of caspase-7 during osteogenesis

Czech Academy of Sciences Publication Activity Database

Švandová, Eva; Lesot, H.; Vanden Berghe, T.; Tucker, A.S.; Sharpe, P. T.; Vandenabeele, P.; Matalová, Eva

2014-01-01

Roč. 5, e1366 (2014) ISSN 2041-4889 R&D Projects: GA ČR GCP302/12/J059 Grant - others:GA ČR(CZ) GAP502/12/1285; AV ČR(CZ) M200451201 Program:GA Institutional support: RVO:67985904 Keywords : osteogenesis Subject RIV: EA - Cell Biology Impact factor: 5.014, year: 2014

Programmed Necrosis: A Prominent Mechanism of Cell Death following Neonatal Brain Injury

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Raul Chavez-Valdez

2012-01-01

Full Text Available Despite the introduction of therapeutic hypothermia, neonatal hypoxic ischemic (HI brain injury remains a common cause of developmental disability. Development of rational adjuvant therapies to hypothermia requires understanding of the pathways of cell death and survival modulated by HI. The conceptualization of the apoptosis-necrosis “continuum” in neonatal brain injury predicts mechanistic interactions between cell death and hydrid forms of cell death such as programmed or regulated necrosis. Many of the components of the signaling pathway regulating programmed necrosis have been studied previously in models of neonatal HI. In some of these investigations, they participate as part of the apoptotic pathways demonstrating clear overlap of programmed death pathways. Receptor interacting protein (RIP-1 is at the crossroads between types of cellular death and survival and RIP-1 kinase activity triggers formation of the necrosome (in complex with RIP-3 leading to programmed necrosis. Neuroprotection afforded by the blockade of RIP-1 kinase following neonatal HI suggests a role for programmed necrosis in the HI injury to the developing brain. Here, we briefly review the state of the knowledge about the mechanisms behind programmed necrosis in neonatal brain injury recognizing that a significant proportion of these data derive from experiments in cultured cell and some from in vivo adult animal models. There are still more questions than answers, yet the fascinating new perspectives provided by the understanding of programmed necrosis in the developing brain may lay the foundation for new therapies for neonatal HI.

Disparate effects of non-steroidal anti-inflammatory drugs on apoptosis in guinea-pig gastric mucous cells: inhibition of basal apoptosis by diclofenac

Science.gov (United States)

Ashton, Miranda; Hanson, Peter J

2002-01-01

Non-steroidal anti-inflammatory drugs (NSAIDs) induce apoptosis in gastrointestinal cancer cell lines. Similar actions on normal gastric epithelial cells could contribute to NSAID gastropathy. The present work therefore compared the actions of diclofenac, ibuprofen, indomethacin, and the cyclo-oxygenase-2 selective inhibitor, NS-398, on a primary culture of guinea-pig gastric mucous epithelial cells. Cell number was assessed by staining with crystal violet. Apoptotic activity was determined by condensation and fragmentation of nuclei and by assay of caspase-3-like activity. Necrosis was evaluated from release of cellular enzymes. Ibuprofen (250 μM for 24 h) promoted cell loss, and apoptosis, under both basal conditions and when apoptosis was increased by 25 μM N-Hexanoyl-D-sphingosine (C6-ceramide). Diclofenac (250 μM for 24 h) reduced the proportion of apoptotic nuclei from 5.2 to 2.1%, and caused inhibition of caspase-3-like activity, without causing necrosis under basal conditions. No such reduction in apoptotic activity was evident in the presence of 25 μM C6-ceramide. The inhibitory effect of diclofenac on basal caspase-3-like activity was also exhibited by the structurally similar mefenamic and flufenamic acids (1–250 μM), but not by niflumic acid. Inhibition of superoxide production by the cells increased caspase-3-like activity, but the inhibitory action of diclofenac on caspase activity remained. Diclofenac did not affect superoxide production. Diclofenac inhibited caspase-3-like activity in cell homogenates and also inhibited human recombinant caspase-3. In conclusion, NSAIDs vary in their effect on apoptotic activity in a primary culture of guinea-pig gastric mucous epithelial cells, and the inhibitory effect of diclofenac on basal apoptosis could involve an action on caspase activity. PMID:11815376

Application of Photoshop-based image analysis and TUNEL for the distribution and quantification of dexamethasone-induced apoptotic cells in rat thymus.

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Hussar, Piret; Tokin, Ivan; Hussar, Ulo; Filimonova, Galina; Suuroja, Toivo

2006-01-01

The aim of the present study was to determine the target site cells in the rat thymus after exposure to the synthetic glucocorticoid, dexamethasone, at therapeutic doses. The findings of histology and histochemistry (Feulgen, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling--TUNEL) with quantification by computerized histomorphometry are described. A quantified investigation of apoptotic and mitotic thymic lymphocytes in 36 young adult Wistar rats was performed at 1-7 days after a 3-day injection of dexamethasone (a total dose of 1.2 mg/rat intraperitoneally). At the first day after dexamethasone administration the moderate involution and atrophy of thymus histology were observed with simultaneous fall in cortical cellularity and mitotic activity of thymocytes. More rapid fall appeared in the inner cortex. The number of apoptotic (TUNEL-positive) cells was significantly increased. On the days 5 and 7 the expression of apoptosis and the cell proliferation were at almost normal level. The findings suggest that dexamethasone-induced apoptosis of cortical thymic lymphocytes, mainly correlated with synchronous inhibition of mitosis and cell number fall in thymus. The main target sites of dexamethasone injury were cells in the inner cortex of lobuli thymi.

Gallic acid induced apoptotic events in HCT-15 colon cancer cells

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Subramanian, Aruna Priyadharshni; Jaganathan, Saravana Kumar; Mandal, Mahitosh; Supriyanto, Eko; Muhamad, Ida Idayu

2016-01-01

AIM: To investigate the inhibitory action of diet-derived phenolic compound gallic acid (GA) against HCT-15 colon cancer cells. METHODS: The antiproliferative effect of GA against colon cancer cells was determined by performing thiazolyl blue tetrazolium bromide (MTT) assay. The colony forming ability of GA treated colon cancer cells was evaluated using the colony forming assay. The cell cycle changes induced by GA in HCT-15 cells were analyzed by propidium iodide staining. Levels of reactive oxygen species (ROS) and mitochondrial membrane potential of HCT-15 exposed to GA was assessed using 2’,7’-dichlorfluorescein-diacetate and rhodamine-123 respectively, with the help of flow cytometry. Morphological changes caused by GA treatment in the colon cancer cells were identified by scanning electron microscope and photomicrograph examination. Apoptosis was confirmed using flow cytometric analysis of GA treated HCT-15 cells after staining with Yo-Pro-1. RESULTS: MTT assay results illustrated that GA has an inhibitory effect on HCT-15 cells with IC50 value of 740 μmol/L. A time-dependent inhibition of colony formation was evident with GA treatment. Cell cycle arrest was evident from the accumulation of GA treated HCT-15 cells at sub-G1 phase (0.98 ± 1.03 vs 58.01 ± 2.05) with increasing exposure time. Flow cytometric analysis of GA treated HCT-15 cells depicted early events associated with apoptosis like lipid layer breakage and fall in mitochondrial membrane potential apart from an increase in the generation of ROS which were in a time dependent manner. SEM and photomicrograph images of the GA-treated cells displayed membrane blebbing and cell shrinking characteristics of apoptosis. Further apoptosis confirmation by Yo-Pro-1 staining also showed the time-dependent increase of apoptotic cells after treatment. CONCLUSION: These results show that GA induced ROS dependent apoptosis and inhibited the growth of colon cancer cells. PMID:27099438