Overexpression of Pygopus2 protects HeLa cells from vinblastine-induced apoptosis

2009 ◽  
Vol 390 (2) ◽  
pp. 157-165 ◽  
Author(s):  
Degejing De ◽  
Apeng Chen ◽  
Zhiqiang Wu ◽  
Songya Lv ◽  
Guoqing He ◽  
...  
Keyword(s):  
Mitochondrial Membrane ◽  
Caspase 3 ◽  
Caspase 9 ◽  
Human Carcinoma ◽  
Multiple Functions ◽  
Apoptotic Protein ◽  
Hela Cell Lines ◽  
Apoptotic Activity ◽  
Induced Apoptosis ◽  
Transcriptional Complex

Abstract Pygopus, a very important component of the Wnt signaling transcriptional complex, has multiple functions in both Wnt-dependent and -independent pathways. Human Pygopus2 (Pygo2) is expressed in many cancers and plays an important role in tumor growth. In the present study, we generated human carcinoma (HeLa) cell lines stably expressing Pygo2, which counteracts vinblastine-induced apoptosis. The anti-apoptotic function was determined by DNA fragmentation, sub-G1 appearance, loss of mitochondrial membrane potential (Δψm) and the activation of caspase-9 and caspase-3. In addition, we found that Pygo2 effectively blocks vinblastine-induced c-Jun and AP-1 activation, maintains the anti-apoptotic protein Bcl-2 in an unphosphorylated state, and thus can render cells resistant to apoptosis. However, Pygo2 does not alter the vinblastine-induced cell cycle changes. Here, we describe an anti-apoptotic activity exerted by Pygo2 through blocking activation of the JNK/AP-1 signaling pathway induced by vinblastine.

scholarly journals Esculetin induces apoptosis of SMMC-7721 cells through IGF-1/PI3K/Akt-mediated mitochondrial pathways

2017 ◽  
Vol 95 (7) ◽  
pp. 787-794 ◽  
Author(s):  
Juan Li ◽  
Shuang Li ◽  
Xiuli Wang ◽  
Hongxin Wang
Keyword(s):  
Mitochondrial Membrane ◽  
Caspase 3 ◽  
Annexin V ◽  
Coumarin Derivative ◽  
Caspase 9 ◽  
Cytochrome C Release ◽  
Dapi Staining ◽  
Cancer Cell Growth ◽  
Induced Apoptosis ◽  
Apoptotic Effects

Esculetin (6,7-dihydroxycoumarin) is a coumarin derivative extracted from natural plants and has been reported to have anticancer activity. However, the mechanism by which esculetin prevents human hepatic cancer cell growth is still largely unknown. In this study, we investigated the effect of esculetin on human hepatocellular carcinoma (HCC) SMMC-7721 cells and explored the cell signal mechanism. Our data indicated that esculetin induced apoptosis in SMMC-7721 cells, which were supported by DAPI staining and Annexin V/PI staining. Meanwhile, esculetin increased the activities of caspase-3 and caspase-9, promoted bax expression, decreased bcl-2 expression, and triggered collapse of mitochondrial membrane potential, and increased cytochrome c release from mitochondria. In addition, the inactivation of IGF-1, PI3K, and Akt was observed after esculetin administration. Furthermore, pretreatment with IGF-1 before esculetin administration abrogated the pro-apoptotic effects of esculetin, while PI3K inhibitor increased the pro-apoptotic effects of esculetin. These results indicated that esculetin induced the apoptosis of SMMC-7721 cells through IGF-1/PI3K/Akt-regulated mitochondrial dysfunction.

scholarly journals Delineation of the Molecular Mechanisms of Francisella tularensis-Induced Apoptosis in Murine Macrophages

2003 ◽  
Vol 71 (8) ◽  
pp. 4642-4646 ◽  
Author(s):  
Xin-He Lai ◽  
Anders Sjöstedt
Keyword(s):  
Francisella Tularensis ◽  
Mitochondrial Membrane ◽  
Molecular Mechanisms ◽  
Caspase 3 ◽  
Live Vaccine Strain ◽  
Intrinsic Apoptotic Pathway ◽  
Caspase 9 ◽  
Apoptotic Pathway ◽  
Murine Macrophages ◽  
Induced Apoptosis

ABSTRACT Francisella tularensis is a facultative intracellular bacterium capable of inducing apoptosis in murine macrophages. Here we analyzed the pathway leading to apoptosis in the murine macrophage-like cell line J774A.1 after infection with F. tularensis strain LVS (named LVS for live vaccine strain). We obtained evidence that the infection affected the mitochondria of the macrophages, since it induced release of the mitochondrial molecule cytochrome c into the cytosol and changed the potential over the mitochondrial membrane. Moreover, activation of caspase 9 and the executioner caspase 3 was also observed in the LVS-infected J774A.1 macrophages. The activated caspase 3 degraded poly(ADP-ribose) polymerase (PARP). All of these events were observed within 9 to 12 h after the initiation of infection, and maximum degradation of a synthetic caspase 3 substrate occurred at 18 h. The internucleosomal fragmentation and PARP degradation resulting from activation of this apoptotic pathway was prevented by the caspase 3 inhibitor Z-DEVD-fmk. No involvement of caspase 1, caspase 8, Bcl-2, or Bid was observed. Thus, the F. tularensis infection induces macrophage apoptosis through a pathway partly resembling the intrinsic apoptotic pathway.

scholarly journals Human Immunodeficiency Virus Type 1 Vpr Interacts with Antiapoptotic Mitochondrial Protein HAX-1

2005 ◽  
Vol 79 (21) ◽  
pp. 13735-13746 ◽  
Author(s):  
Venkat S. R. K. Yedavalli ◽  
Hsiu-Ming Shih ◽  
Yu-Ping Chiang ◽  
Chun-Yi Lu ◽  
Luan-Yin Chang ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Mitochondrial Membrane ◽  
Caspase 3 ◽  
Mitochondrial Protein ◽  
Caspase 9 ◽  
T Cell Apoptosis ◽  
Immunodeficiency Virus

ABSTRACT Human immunodeficiency virus type 1 viral protein R (Vpr) is required for viral pathogenesis and has been implicated in T-cell apoptosis through its activation of caspase 3 and caspase 9 and perturbation of mitochondrial membrane potential. To understand better Vpr-mitochondria interaction, we report here the identification of antiapoptotic mitochondrial protein HAX-1 as a novel Vpr target. We show that Vpr and HAX-1 physically associate with each other. Overexpression of Vpr in cells dislocates HAX-1 from its normal residence in mitochondria and creates mitochondrion instability and cell death. Conversely, overexpression of HAX-1 suppressed the proapoptotic activity of Vpr.

Reactive oxygen species and caspase activation mediate silica-induced apoptosis in alveolar macrophages

2001 ◽  
Vol 280 (1) ◽  
pp. L10-L17 ◽  
Author(s):  
Han-Ming Shen ◽  
Zhuo Zhang ◽  
Qi-Feng Zhang ◽  
Choon-Nam Ong
Keyword(s):  
Reactive Oxygen Species ◽  
Cell Death ◽  
Alveolar Macrophages ◽  
Caspase 3 ◽  
Reactive Oxygen ◽  
Parp Cleavage ◽  
Oxygen Species ◽  
Caspase Activation ◽  
Caspase 9 ◽  
Induced Apoptosis

Alveolar macrophages (AMs) are the principal target cells of silica and occupy a key position in the pathogenesis of silica-related diseases. Silica has been found to induce apoptosis in AMs, whereas its underlying mechanisms involving the initiation and execution of apoptosis are largely unknown. The main objective of the present study was to examine the form of cell death caused by silica and the mechanisms involved. Silica-induced apoptosis in AMs was evaluated by terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling assay and cell cycle/DNA content analysis. The elevated level of reactive oxygen species (ROS), caspase-9 and caspase-3 activation, and poly(ADP-ribose) polymerase (PARP) cleavage in silica-treated AMs were also determined. The results showed that there was a temporal pattern of apoptotic events in silica-treated AMs, starting with ROS formation and followed by caspase-9 and caspase-3 activation, PARP cleavage, and DNA fragmentation. Silica-induced apoptosis was significantly attenuated by a caspase-3 inhibitor, N-acetyl-Asp-Glu-Val-Asp aldehyde, and ebselen, a potent antioxidant. These findings suggest that apoptosis is an important form of cell death caused by silica exposure in which the elevated ROS level that results from silica exposure may act as an initiator, leading to caspase activation and PARP cleavage to execute the apoptotic process.

scholarly journals Inclusion Complex of Zerumbone with Hydroxypropyl-β-Cyclodextrin Induces Apoptosis in Liver Hepatocellular HepG2 Cells via Caspase 8/BID Cleavage Switch and Modulating Bcl2/Bax Ratio

2013 ◽  
Vol 2013 ◽  
pp. 1-16 ◽  
Author(s):  
Nabilah Muhammad Nadzri ◽  
Ahmad Bustamam Abdul ◽  
Mohd Aspollah Sukari ◽  
Siddig Ibrahim Abdelwahab ◽  
Eltayeb E. M. Eid ◽  
...  
Keyword(s):  
Inclusion Complex ◽  
Mitochondrial Membrane ◽  
Morphological Study ◽  
Caspase 3 ◽  
Anticancer Agent ◽  
Caspase 8 ◽  
Caspase 9 ◽  
Solubility In Water ◽  
Anticancer Effects ◽  
First Time

Zerumbone (ZER) isolated fromZingiber zerumbetwas previously encapsulated with hydroxypropyl-β-cyclodextrin (HPβCD) to enhance ZER’s solubility in water, thus making it highly tolerable in the human body. The anticancer effects of this new ZER-HPβCD inclusion complex via apoptosis cell death were assessed in this study for the first time in liver hepatocellular cells, HepG2. Apoptosis was ascertained by morphological study, nuclear stain, and sub-G1 cell population accumulation with G2/M arrest. Further investigations showed the release of cytochrome c and loss of mitochondrial membrane potential, proving mitochondrial dysfunction upon the ZER-HPβCD treatment as well as modulating proapoptotic and anti-apototic Bcl-2 family members. A significant increase in caspase 3/7, caspase 9, and caspase 8 was detected with the depletion of BID cleaved by caspase 8. Collectively, these results prove that a highly soluble inclusion complex of ZER-HPβCD could be a promising anticancer agent for the treatment of hepatocellular carcinoma in humans.

4-Acetyl-12,13-Epoxyl-9-Trichothecene-3,15-Diol from Isaria japonica Mediates Apoptosis of Rat Bladder Carcinoma NBT-II Cells by Decreasing Anti-apoptotic Bcl-2 Expression and Increasing Pro-apoptotic Bax Expression

2004 ◽  
Vol 32 (03) ◽  
pp. 377-387 ◽  
Author(s):  
Hyung-Jin Kim ◽  
Seon Il Jang ◽  
Young-Jun Kim ◽  
Hyun-Ock Pae ◽  
Hae-Young Won ◽  
...  
Keyword(s):  
Cell Death ◽  
Bladder Carcinoma ◽  
Cytotoxic Effect ◽  
Caspase 3 ◽  
Apoptotic Cell ◽  
Morphological Changes ◽  
Rat Bladder ◽  
Apoptotic Protein ◽  
Induction Of Apoptosis ◽  
Induced Apoptosis

We studied the effect of 4-acetyl-12,13-epoxyl-9-trichothecene-3,15-diol (AETD) isolated from Isaria japonica, one of the most popular Chinese fungal medicines, on the induction of apoptosis in rat bladder carcinoma NBT-II cells. AETD was cytotoxic to NBT-II cells, and this cytotoxic effect appears to be attributed to its induction of apoptotic cell death, as AETD induced nuclear morphological changes and internucleosomal DNA fragmentation, and increased the proportion of hypodiploid cells and activity of caspase-3. AETD treatment also decreased the expression of the anti-apoptotic protein Bcl-2 and increased the expression of the pro-apoptotic protein Bax. These results provide important information in understanding the mechanism(s) of AETD-induced apoptosis.

scholarly journals Engineering ML-IAP to produce an extraordinarily potent caspase 9 inhibitor: implications for Smac-dependent anti-apoptotic activity of ML-IAP

2004 ◽  
Vol 385 (1) ◽  
pp. 11-20 ◽  
Author(s):  
Domagoj VUCIC ◽  
Matthew C. FRANKLIN ◽  
Heidi J. A. WALLWEBER ◽  
Kanad DAS ◽  
Brendan P. ECKELMAN ◽  
...  
Keyword(s):  
Mutational Analysis ◽  
Caspase 9 ◽  
Direct Inhibition ◽  
The Third ◽  
Apoptotic Protein ◽  
Iap Antagonist ◽  
Repeat Domain ◽  
Apoptotic Activity ◽  
Bir Domain ◽  
Better Than

ML-IAP (melanoma inhibitor of apoptosis) is a potent anti-apoptotic protein that is strongly up-regulated in melanoma and confers protection against a variety of pro-apoptotic stimuli. The mechanism by which ML-IAP regulates apoptosis is unclear, although weak inhibition of caspases 3 and 9 has been reported. Here, the binding to and inhibition of caspase 9 by the single BIR (baculovirus IAP repeat) domain of ML-IAP has been investigated and found to be significantly less potent than the ubiquitously expressed XIAP (X-linked IAP). Engineering of the ML-IAP-BIR domain, based on comparisons with the third BIR domain of XIAP, resulted in a chimeric BIR domain that binds to and inhibits caspase 9 significantly better than either ML-IAP-BIR or XIAP-BIR3. Mutational analysis of the ML-IAP-BIR domain demonstrated that similar enhancements in caspase 9 affinity can be achieved with only three amino acid substitutions. However, none of these modifications affected binding of the ML-IAP-BIR domain to the IAP antagonist Smac (second mitochondrial activator of caspases). ML-IAP-BIR was found to bind mature Smac with low nanomolar affinity, similar to that of XIAP-BIR2-BIR3. Correspondingly, increased expression of ML-IAP results in formation of a ML-IAP–Smac complex and disruption of the endogenous interaction between XIAP and mature Smac. These results suggest that ML-IAP might regulate apoptosis by sequestering Smac and preventing it from antagonizing XIAP-mediated inhibition of caspases, rather than by direct inhibition of caspases.

Volatile Anesthetics Induce Caspase-dependent, Mitochondria-mediated Apoptosis in Human T Lymphocytes In Vitro 

2005 ◽  
Vol 102 (6) ◽  
pp. 1147-1157 ◽  
Author(s):  
Torsten Loop ◽  
David Dovi-Akue ◽  
Michael Frick ◽  
Martin Roesslein ◽  
Lotti Egger ◽  
...  
Keyword(s):  
Membrane Potential ◽  
T Lymphocytes ◽  
Cytochrome C ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Caspase 3 ◽  
Volatile Anesthetics ◽  
Human T Lymphocytes ◽  
Induced Apoptosis

Background Volatile anesthetics modulate lymphocyte function during surgery, and this compromises postoperative immune competence. The current work was undertaken to examine whether volatile anesthetics induce apoptosis in human T lymphocytes and what apoptotic signaling pathway might be used. Methods Effects of sevoflurane, isoflurane, and desflurane were studied in primary human CD3 T lymphocytes and Jurkat T cells in vitro. Apoptosis and mitochondrial membrane potential were assessed using flow cytometry after green fluorescent protein-annexin V and DiOC6-fluorochrome staining. Activity and proteolytic processing of caspase 3 was measured by cleaving of the fluorogenic effector caspase substrate Ac-DEVD-AMC and by anti-caspase-3 Western blotting. Release of mitochondrial cytochrome c was studied after cell fractionation using anti-cytochrome c Western blotting and enzyme-linked immunosorbent assays. Results Sevoflurane and isoflurane induced apoptosis in human T lymphocytes in a dose-dependent manner. By contrast, desflurane did not exert any proapoptotic effects. The apoptotic signaling pathway used by sevoflurane involved disruption of the mitochondrial membrane potential and release of cytochrome c from mitochondria to the cytosol. In addition, the authors observed a proteolytic cleavage of the inactive p32 procaspase 3 to the active p17 fragment, increased caspase-3-like activity, and cleavage of the caspase-3 substrate poly-ADP-ribose-polymerase. Sevoflurane-induced apoptosis was blocked by the general caspase inhibitor Z-VAD.fmk. Death signaling was not mediated via the Fas/CD95 receptor pathway because neither anti-Fas/CD95 receptor antagonism nor FADD deficiency or caspase-8 deficiency were able to attenuate sevoflurane-mediated apoptosis. Conclusion Sevoflurane and isoflurane induce apoptosis in T lymphocytes via increased mitochondrial membrane permeability and caspase-3 activation, but independently of death receptor signaling.

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