751
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Tanel A, Pallepati P, Bettaieb A, Morin P, Averill-Bates DA. Acrolein activates cell survival and apoptotic death responses involving the endoplasmic reticulum in A549 lung cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:827-35. [DOI: 10.1016/j.bbamcr.2013.12.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 12/05/2013] [Accepted: 12/18/2013] [Indexed: 12/29/2022]
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752
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Cokol M, Weinstein ZB, Yilancioglu K, Tasan M, Doak A, Cansever D, Mutlu B, Li S, Rodriguez-Esteban R, Akhmedov M, Guvenek A, Cokol M, Cetiner S, Giaever G, Iossifov I, Nislow C, Shoichet B, Roth FP. Large-scale identification and analysis of suppressive drug interactions. CHEMISTRY & BIOLOGY 2014; 21:541-551. [PMID: 24704506 PMCID: PMC4281482 DOI: 10.1016/j.chembiol.2014.02.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Revised: 01/26/2014] [Accepted: 02/07/2014] [Indexed: 11/29/2022]
Abstract
One drug may suppress the effects of another. Although knowledge of drug suppression is vital to avoid efficacy-reducing drug interactions or discover countermeasures for chemical toxins, drug-drug suppression relationships have not been systematically mapped. Here, we analyze the growth response of Saccharomyces cerevisiae to anti-fungal compound ("drug") pairs. Among 440 ordered drug pairs, we identified 94 suppressive drug interactions. Using only pairs not selected on the basis of their suppression behavior, we provide an estimate of the prevalence of suppressive interactions between anti-fungal compounds as 17%. Analysis of the drug suppression network suggested that Bromopyruvate is a frequently suppressive drug and Staurosporine is a frequently suppressed drug. We investigated potential explanations for suppressive drug interactions, including chemogenomic analysis, coaggregation, and pH effects, allowing us to explain the interaction tendencies of Bromopyruvate.
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Affiliation(s)
- Murat Cokol
- Biological Sciences and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey; Nanotechnology Research and Application Center, Sabanci University, Istanbul 34956, Turkey.
| | - Zohar B Weinstein
- Biological Sciences and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey; Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Kaan Yilancioglu
- Biological Sciences and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey; Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Murat Tasan
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Allison Doak
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Dilay Cansever
- Biological Sciences and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey; Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Beste Mutlu
- Biological Sciences and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey; Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Siyang Li
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Raul Rodriguez-Esteban
- Department of Computational Biology, Boehringer Ingelheim Pharmaceuticals, Ridgefield, CT 06877, USA
| | - Murodzhon Akhmedov
- Biological Sciences and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey
| | - Aysegul Guvenek
- Biological Sciences and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey
| | - Melike Cokol
- Biological Sciences and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey
| | - Selim Cetiner
- Biological Sciences and Bioengineering Program, Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey
| | - Guri Giaever
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada
| | - Ivan Iossifov
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Corey Nislow
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada
| | - Brian Shoichet
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Frederick P Roth
- Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Center for Cancer Systems Biology, Dana-Farber Cancer Institute, One Jimmy Fund Way, Boston, MA 02215, USA; Lunenfeld-Tanenbaum Research Institute, Mt. Sinai Hospital, Toronto, ON M5G 1X5, Canada; Departments of Molecular Genetics and Computer Science, University of Toronto, Toronto, ON M5S 3E1, Canada.
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753
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Cipponi A, Thomas DM. Stress-induced cellular adaptive strategies: ancient evolutionarily conserved programs as new anticancer therapeutic targets. Bioessays 2014; 36:552-60. [PMID: 24706439 DOI: 10.1002/bies.201300170] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Despite the remarkable achievements of novel targeted anti-cancer drugs, most therapies only produce remission for a limited time, resistance to treatment, and relapse, often being the ultimate outcome. Drug resistance is due to highly efficient adaptive strategies utilized by cancer cells. Exogenous and endogenous stress stimuli are known to induce first-line responses, capable of re-establishing cellular homeostasis and determining cell fate decisions. Cancer cells may also mount second-line adaptive strategies, such as the mutator response. Hypermutable subpopulations of cells may expand under severe selective stress, thereby accelerating the emergence of adapted clones. As with first-line protective responses, these strategies appear highly conserved, and are found in yeasts and bacteria. We hypothesize that evolutionarily conserved programs rheostatically regulate mutability in fluctuating environments, and contribute to drug resistance in cancer cells. Elucidating the conserved genetic and molecular mechanisms may present novel opportunities to increase the effectiveness of cancer therapies.
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Affiliation(s)
- Arcadi Cipponi
- Sarcoma Genomics and Genetics, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
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754
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Mihailidou C, Papavassiliou AG, Kiaris H. A crosstalk between p21 and UPR-induced transcription factor C/EBP homologous protein (CHOP) linked to type 2 diabetes. Biochimie 2014; 99:19-27. [DOI: 10.1016/j.biochi.2013.11.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 11/06/2013] [Indexed: 02/04/2023]
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755
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Mackeh R, Lorin S, Ratier A, Mejdoubi-Charef N, Baillet A, Bruneel A, Hamaï A, Codogno P, Poüs C, Perdiz D. Reactive oxygen species, AMP-activated protein kinase, and the transcription cofactor p300 regulate α-tubulin acetyltransferase-1 (αTAT-1/MEC-17)-dependent microtubule hyperacetylation during cell stress. J Biol Chem 2014; 289:11816-11828. [PMID: 24619423 DOI: 10.1074/jbc.m113.507400] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Beyond its presence in stable microtubules, tubulin acetylation can be boosted after UV exposure or after nutrient deprivation, but the mechanisms of microtubule hyperacetylation are still unknown. In this study, we show that this hyperacetylation is a common response to several cellular stresses that involves the stimulation of the major tubulin acetyltransferase MEC-17. We also demonstrate that the acetyltransferase p300 negatively regulates MEC-17 expression and is sequestered on microtubules upon stress. We further show that reactive oxygen species of mitochondrial origin are required for microtubule hyperacetylation by activating the AMP kinase, which in turn mediates MEC-17 phosphorylation upon stress. Finally, we show that preventing microtubule hyperacetylation by knocking down MEC-17 affects cell survival under stress conditions and starvation-induced autophagy, thereby pointing out the importance of this rapid modification as a broad cell response to stress.
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Affiliation(s)
- Rafah Mackeh
- Université Paris Sud, EA4530, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Séverine Lorin
- Université Paris Sud, EA4530, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Ameetha Ratier
- Université Paris Sud, EA4530, Faculté de Pharmacie, Châtenay-Malabry, France
| | | | - Anita Baillet
- Université Paris Sud, EA4530, Faculté de Pharmacie, Châtenay-Malabry, France
| | - Arnaud Bruneel
- Université Paris Sud, EA4530, Faculté de Pharmacie, Châtenay-Malabry, France; Assistance Publique-Hôpitaux de Paris, Service de Biochimie Métabolique et Cellulaire, Hôpital Bichat, 75018 Paris, France
| | - Ahmed Hamaï
- INSERM U845, Université Paris Descartes, 75014 Paris, France
| | - Patrice Codogno
- INSERM U845, Université Paris Descartes, 75014 Paris, France
| | - Christian Poüs
- Université Paris Sud, EA4530, Faculté de Pharmacie, Châtenay-Malabry, France; Biochimie-Hormonologie, Hôpital Antoine Béclère, Assistance Publique-Hôpitaux de Paris, 92141 Clamart, France.
| | - Daniel Perdiz
- Université Paris Sud, EA4530, Faculté de Pharmacie, Châtenay-Malabry, France
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756
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Kuzmanov A, Karina EI, Kirienko NV, Fay DS. The conserved PBAF nucleosome-remodeling complex mediates the response to stress in Caenorhabditis elegans. Mol Cell Biol 2014; 34:1121-35. [PMID: 24421384 PMCID: PMC3958046 DOI: 10.1128/mcb.01502-13] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 12/12/2013] [Accepted: 12/30/2013] [Indexed: 11/20/2022] Open
Abstract
To adapt to stress, cells must undergo major changes in their gene expression profiles. We have previously described a largely uncharacterized stress response pathway in Caenorhabditis elegans that acts through an evolutionarily conserved motif, termed ESRE, for ethanol and stress response element. We characterize here the requirements for ESRE gene expression and show that the ESRE network is regulated by a conserved SWI/SNF family nucleosome remodeling complex termed PBAF. Depletion of PBAF subunits SWSN-7/BAF200 and PBRM-1/BAF180 results in decreased expression of ESRE genes and increased sensitivity to thermal stress. When overexpressed, SWSN-7/BAF200 and PBRM-1/BAF180 led to increased ESRE transcription, enhanced thermotolerance, and induction of a nuclear ESRE-binding activity. Our data support a model in which PBAF is recruited by an ESRE-binding protein to genomic ESRE sites. We also show that the closely related SWI/SNF complex, BAF, which regulates stress induction through DAF-16/FOXO, does not contribute to ESRE gene expression or bind directly to ESRE sites. To our knowledge, this is the first report demonstrating direct and specific regulation of a stress response network by the PBAF nucleosome-remodeling complex in vivo in metazoa. In addition, we show that PBAF cooperates with the histone demethylase, JMJC-1/NO66, to promote expression of ESRE genes following stress.
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Affiliation(s)
- Aleksandra Kuzmanov
- Department of Molecular Biology, College of Agriculture and Natural Resources, University of Wyoming, Laramie, Wyoming, USA
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757
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Al-Khalili L, de Castro Barbosa T, Östling J, Massart J, Katayama M, Nyström AC, Oscarsson J, Zierath JR. Profiling of human myotubes reveals an intrinsic proteomic signature associated with type 2 diabetes. TRANSLATIONAL PROTEOMICS 2014. [DOI: 10.1016/j.trprot.2013.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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758
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Chen CH, Ferreira JCB, Gross ER, Mochly-Rosen D. Targeting aldehyde dehydrogenase 2: new therapeutic opportunities. Physiol Rev 2014; 94:1-34. [PMID: 24382882 DOI: 10.1152/physrev.00017.2013] [Citation(s) in RCA: 421] [Impact Index Per Article: 42.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A family of detoxifying enzymes called aldehyde dehydrogenases (ALDHs) has been a subject of recent interest, as its role in detoxifying aldehydes that accumulate through metabolism and to which we are exposed from the environment has been elucidated. Although the human genome has 19 ALDH genes, one ALDH emerges as a particularly important enzyme in a variety of human pathologies. This ALDH, ALDH2, is located in the mitochondrial matrix with much known about its role in ethanol metabolism. Less known is a new body of research to be discussed in this review, suggesting that ALDH2 dysfunction may contribute to a variety of human diseases including cardiovascular diseases, diabetes, neurodegenerative diseases, stroke, and cancer. Recent studies suggest that ALDH2 dysfunction is also associated with Fanconi anemia, pain, osteoporosis, and the process of aging. Furthermore, an ALDH2 inactivating mutation (termed ALDH2*2) is the most common single point mutation in humans, and epidemiological studies suggest a correlation between this inactivating mutation and increased propensity for common human pathologies. These data together with studies in animal models and the use of new pharmacological tools that activate ALDH2 depict a new picture related to ALDH2 as a critical health-promoting enzyme.
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759
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Russo R, Bonaventura R, Matranga V. Time- and dose-dependent gene expression in sea urchin embryos exposed to UVB. MARINE ENVIRONMENTAL RESEARCH 2014; 93:85-92. [PMID: 24011617 DOI: 10.1016/j.marenvres.2013.08.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 08/02/2013] [Accepted: 08/07/2013] [Indexed: 06/02/2023]
Abstract
The increase of UVB radiation reaching marine environment has harmful effects on living organisms. Paracentrotus lividus sea urchin embryos living in shallow water are exposed to radiations, providing a good model for studying the molecular mechanisms activated upon UV stress. Here, we report the modulated time- and dose-dependent expression of six genes, known to be involved in stress response, in embryos exposed at cleavage to 400 and 800 J/m(2) UVB, and collected at early (morula) and later (gastrula) stages. We analyzed their mRNA levels by QPCR and found that Pl-14-3-3 showed a dose-dependent induction, both early and late in development; Pl-c-jun was up-regulated proportionally to the UVB dose at early stages and only at 800 J/m(2) UVB at later stages; Pl-XPB-ERCC3, Pl-MT and Pl-NF-kB were highly up-regulated later in development at the high dose, with the exception of Pl-XPB-ERCC3 whose mRNA levels were high also at the lower dose; Pl-FOXO expression was not affected by UVB radiation. We believe that the identification of UVB-responsive genes in irradiated sea urchin embryos, reported for the first time in this study, will be helpful for the understanding of the involved molecular pathways. The correlation between the impaired morphogenesis, affecting endo-mesoderm differentiation, and gene modulations described herewith is also discussed.
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Affiliation(s)
- Roberta Russo
- Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Via Ugo La Malfa 153, 90146 Palermo, Italy.
| | - Rosa Bonaventura
- Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Via Ugo La Malfa 153, 90146 Palermo, Italy
| | - Valeria Matranga
- Consiglio Nazionale delle Ricerche, Istituto di Biomedicina e Immunologia Molecolare "Alberto Monroy", Via Ugo La Malfa 153, 90146 Palermo, Italy
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760
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Dihydromyricetin induces autophagy in HepG2 cells involved in inhibition of mTOR and regulating its upstream pathways. Food Chem Toxicol 2014; 66:7-13. [PMID: 24444546 DOI: 10.1016/j.fct.2014.01.014] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Revised: 01/06/2014] [Accepted: 01/09/2014] [Indexed: 01/04/2023]
Abstract
Dihydromyricetin (DHM), a bioactive flavonoid compound extracted from the stems and leaves of Ampelopsis grossedentata, has oxidation resistance, anti-tumor and free radical scavenging capabilities. In this study, we found that DHM-induced autophagy inhibited the cell proliferation in HepG2 cells. The transmission electron microscopy results showed that DHM induced significantly autophagosome characteristics like autophagolysosome containing degraded cellular content. GFP labled LC3 plasma transfection showed that LC3 largely diffused to punctate structures with DHM treatment, while lysosomal-rich/acidic compartments detected using LysoTracker Red staining. In addition, DHM promoted the expressions of LC3-II and Beclin-1 in a dose- and time-dependent manner. Further study showed that DHM suppressed the activation of mTOR (mammalian targets of rapamycin) involved in regulating its upstream signaling pathways including extracellular signal-regulated kinase 1/2 (ERK1/2), AMPK (AMP-activated kinase) and class III phosphatidylinositol 3-kinase/phosphoinositide-dependent protein kinase 1/protein kinase B (PI3K/PDK 1/Akt) pathways. Taken together, all the results demonstrated that DHM-induced autophagy inhibited the cell proliferation in HepG2 cells, the possible mechanism involved in inhibition of mTOR activation and regulating the related upstream signaling pathways.
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761
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The role of heat shock proteins in Amyotrophic Lateral Sclerosis: The therapeutic potential of Arimoclomol. Pharmacol Ther 2014; 141:40-54. [DOI: 10.1016/j.pharmthera.2013.08.003] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 07/29/2013] [Indexed: 12/11/2022]
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762
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Clifford RJ, Kaplan JH. Human breast tumor cells are more resistant to cardiac glycoside toxicity than non-tumorigenic breast cells. PLoS One 2013; 8:e84306. [PMID: 24349570 PMCID: PMC3862803 DOI: 10.1371/journal.pone.0084306] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 11/13/2013] [Indexed: 12/28/2022] Open
Abstract
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.
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Affiliation(s)
- Rebecca J. Clifford
- Department of Biochemistry and Molecular Genetics, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Jack H. Kaplan
- Department of Biochemistry and Molecular Genetics, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- * E-mail:
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763
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Ebrahimi-Fakhari D, Saidi LJ, Wahlster L. Molecular chaperones and protein folding as therapeutic targets in Parkinson's disease and other synucleinopathies. Acta Neuropathol Commun 2013; 1:79. [PMID: 24314025 PMCID: PMC4046681 DOI: 10.1186/2051-5960-1-79] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 11/25/2013] [Indexed: 12/20/2022] Open
Abstract
Changes in protein metabolism are key to disease onset and progression in many neurodegenerative diseases. As a prime example, in Parkinson's disease, folding, post-translational modification and recycling of the synaptic protein α-synuclein are clearly altered, leading to a progressive accumulation of pathogenic protein species and the formation of intracellular inclusion bodies. Altered protein folding is one of the first steps of an increasingly understood cascade in which α-synuclein forms complex oligomers and finally distinct protein aggregates, termed Lewy bodies and Lewy neurites. In neurons, an elaborated network of chaperone and co-chaperone proteins is instrumental in mediating protein folding and re-folding. In addition to their direct influence on client proteins, chaperones interact with protein degradation pathways such as the ubiquitin-proteasome-system or autophagy in order to ensure the effective removal of irreversibly misfolded and potentially pathogenic proteins. Because of the vital role of proper protein folding for protein homeostasis, a growing number of studies have evaluated the contribution of chaperone proteins to neurodegeneration. We herein review our current understanding of the involvement of chaperones, co-chaperones and chaperone-mediated autophagy in synucleinopathies with a focus on the Hsp90 and Hsp70 chaperone system. We discuss genetic and pathological studies in Parkinson's disease as well as experimental studies in models of synucleinopathies that explore molecular chaperones and protein degradation pathways as a novel therapeutic target. To this end, we examine the capacity of chaperones to prevent or modulate neurodegeneration and summarize the current progress in models of Parkinson's disease and related neurodegenerative disorders.
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764
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The human septin7 and the yeast CDC10 septin prevent Bax and copper mediated cell death in yeast. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:3186-3194. [DOI: 10.1016/j.bbamcr.2013.09.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 09/08/2013] [Accepted: 09/10/2013] [Indexed: 01/18/2023]
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765
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Gao D, Xu Z, Zhang X, Zhu C, Wang Y, Min W. Cadmium triggers kidney cell apoptosis of purse red common carp (Cyprinus carpio) without caspase-8 activation. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2013; 41:728-737. [PMID: 23954723 DOI: 10.1016/j.dci.2013.08.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 07/31/2013] [Accepted: 08/02/2013] [Indexed: 06/02/2023]
Abstract
Caspase-8, the essential initiator caspase, is believed to play a pivotal role in death receptor-mediated apoptotic pathway. It also participates in mitochondria-mediated apoptosis via cleavage of proapoptotic Bid in mammals. However, its role in fish remains elusive in Cadmium-induced apoptotic pathway. In this study, we isolated the caspase-8 gene from common carp, one of the most important industrial aquatic animals in China using rapid amplification of cDNA ends (RACE). The deduced amino acid sequence of caspase-8 comprised 475 amino acids, which showed approximately 64.1% identity and 79.8% similarity to zebrafish (Danio rerio) caspase-8, possessed two conserved death effector domains, a large subunit and a small subunit. Phylogenetic analysis demonstrated that caspase-8 formed a clade with zebrafish caspase-8. In kidney, cadmium (Cd) exposure triggered apoptosis and increased caspase-3 and -9 activities, whereas it did not affect caspase-8 activity. Real-time quantitative PCR analysis revealed that caspase-8 transcriptional level was not significantly increased in kidney after exposure to Cd. Using Western blot analysis, no caspase-8 cleaved fragment was detected and no significant alteration of procaspase-8 level was found with the same Cd-treated condition. Moreover, the immunopositive staining was predominantly limited to the cytoplasm of renal tubular epithelial cells and no remarkable changes of immunoreactivities were observed using immunohistochemical detection after Cd treatment. The results reveal that Cd can trigger apoptosis, while it cannot activate caspase-8 in purse red common carp.
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Affiliation(s)
- Dian Gao
- Medical College of Nanchang University, Nanchang 330006, PR China; Institute of Immunotherapy, Nanchang University, Nanchang 330006, PR China
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766
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Jacobs LA, Bewicke-Copley F, Poolman MG, Pink RC, Mulcahy LA, Baker I, Beaman EM, Brooks T, Caley DP, Cowling W, Currie JMS, Horsburgh J, Kenehan L, Keyes E, Leite D, Massa D, McDermott-Rouse A, Samuel P, Wood H, Kadhim M, Carter DRF. Meta-analysis using a novel database, miRStress, reveals miRNAs that are frequently associated with the radiation and hypoxia stress-responses. PLoS One 2013; 8:e80844. [PMID: 24244721 PMCID: PMC3828287 DOI: 10.1371/journal.pone.0080844] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 10/12/2013] [Indexed: 01/08/2023] Open
Abstract
Organisms are often exposed to environmental pressures that affect homeostasis, so it is important to understand the biological basis of stress-response. Various biological mechanisms have evolved to help cells cope with potentially cytotoxic changes in their environment. miRNAs are small non-coding RNAs which are able to regulate mRNA stability. It has been suggested that miRNAs may tip the balance between continued cytorepair and induction of apoptosis in response to stress. There is a wealth of data in the literature showing the effect of environmental stress on miRNAs, but it is scattered in a large number of disparate publications. Meta-analyses of this data would produce added insight into the molecular mechanisms of stress-response. To facilitate this we created and manually curated the miRStress database, which describes the changes in miRNA levels following an array of stress types in eukaryotic cells. Here we describe this database and validate the miRStress tool for analysing miRNAs that are regulated by stress. To validate the database we performed a cross-species analysis to identify miRNAs that respond to radiation. The analysis tool confirms miR-21 and miR-34a as frequently deregulated in response to radiation, but also identifies novel candidates as potentially important players in this stress response, including miR-15b, miR-19b, and miR-106a. Similarly, we used the miRStress tool to analyse hypoxia-responsive miRNAs. The most frequently deregulated miRNAs were miR-210 and miR-21, as expected. Several other miRNAs were also found to be associated with hypoxia, including miR-181b, miR-26a/b, miR-106a, miR-213 and miR-192. Therefore the miRStress tool has identified miRNAs with hitherto unknown or under-appreciated roles in the response to specific stress types. The miRStress tool, which can be used to uncover new insight into the biological roles of miRNAs, and also has the potential to unearth potential biomarkers for therapeutic response, is freely available at http://mudshark.brookes.ac.uk/MirStress.
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Affiliation(s)
- Laura Ann Jacobs
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Findlay Bewicke-Copley
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Mark Graham Poolman
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Ryan Charles Pink
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Laura Ann Mulcahy
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Isabel Baker
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Ellie-May Beaman
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Travis Brooks
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Daniel Paul Caley
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
- Canada’s Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, British Columbia, Canada
| | - William Cowling
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | | | - Jessica Horsburgh
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Lottie Kenehan
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Emma Keyes
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Daniel Leite
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Davide Massa
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Adam McDermott-Rouse
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Priya Samuel
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Hannah Wood
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Munira Kadhim
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
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767
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Üner N, Piner P, Temiz Ö. Piperonyl Butoxide Increases Oxidative Toxicity of Fenthion in the Brain ofOreochromis niloticus. J Biochem Mol Toxicol 2013; 28:84-90. [DOI: 10.1002/jbt.21539] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 09/30/2013] [Accepted: 10/16/2013] [Indexed: 01/22/2023]
Affiliation(s)
- Nevin Üner
- Faculty of Science and Letters, Department of Biology; University of Cukurova; Balcalı Adana Turkey
| | - Petek Piner
- Faculty of Education, Division of Science Education; Kahramanmaraş Sütçü İmam University; Avşar Campus Kahramanmaraş Turkey
| | - Özge Temiz
- Faculty of Science and Letters, Department of Biology; University of Cukurova; Balcalı Adana Turkey
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768
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Velichko AK, Markova EN, Petrova NV, Razin SV, Kantidze OL. Mechanisms of heat shock response in mammals. Cell Mol Life Sci 2013; 70:4229-41. [PMID: 23633190 PMCID: PMC11113869 DOI: 10.1007/s00018-013-1348-7] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 04/12/2013] [Accepted: 04/15/2013] [Indexed: 12/28/2022]
Abstract
Heat shock (HS) is one of the best-studied exogenous cellular stresses. The cellular response to HS utilizes ancient molecular networks that are based primarily on the action of stress-induced heat shock proteins and HS factors. However, in one way or another, all cellular compartments and metabolic processes are involved in such a response. In this review, we aimed to summarize the experimental data concerning all aspects of the HS response in mammalian cells, such as HS-induced structural and functional alterations of cell membranes, the cytoskeleton and cellular organelles; the associated pathways that result in different modes of cell death and cell cycle arrest; and the effects of HS on transcription, splicing, translation, DNA repair, and replication.
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Affiliation(s)
- Artem K. Velichko
- Laboratory of Structural and Functional Organization of Chromosomes, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Elena N. Markova
- Laboratory of Structural and Functional Organization of Chromosomes, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
| | - Nadezhda V. Petrova
- Laboratory of Structural and Functional Organization of Chromosomes, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
- Department of Molecular Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Sergey V. Razin
- Laboratory of Structural and Functional Organization of Chromosomes, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
- Department of Molecular Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Omar L. Kantidze
- Laboratory of Structural and Functional Organization of Chromosomes, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia
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769
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Guaragnella N, Palermo V, Galli A, Moro L, Mazzoni C, Giannattasio S. The expanding role of yeast in cancer research and diagnosis: insights into the function of the oncosuppressors p53 and BRCA1/2. FEMS Yeast Res 2013; 14:2-16. [PMID: 24103154 DOI: 10.1111/1567-1364.12094] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 07/26/2013] [Accepted: 09/12/2013] [Indexed: 12/16/2022] Open
Abstract
When the glucose supply is high, despite the presence of oxygen, Saccharomyces cerevisiae uses fermentation as its main metabolic pathway and switches to oxidative metabolism only when this carbon source is limited. There are similarities between glucose-induced repression of oxidative metabolism of yeast and metabolic reprogramming of tumor cells. The glucose-induced repression of oxidative metabolism is regulated by oncogene homologues in yeast, such as RAS and Sch9p, the yeast homologue of Akt. Yeast also undergoes an apoptosis-like programmed cell death process sharing several features with mammalian apoptosis, including oxidative stress and a major role played by mitochondria. Evasion of apoptosis and sustained proliferative signaling are hallmarks of cancer. This, together with the possibility of heterologous expression of human genes in yeast, has allowed new insights to be obtained into the function of mammalian oncogenes/oncosuppressors. Here, we elaborate on the similarities between tumor and yeast cells underpinning the use of this model organism in cancer research. We also review the achievements obtained through heterologous expression in yeast of p53, BRCA1, and BRCA2, which are among the best-known cancer-susceptibility genes, with the aim of understanding their role in tumorigenesis. Yeast-cell-based functional assays for cancer genetic testing will also be dealt with.
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770
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Hahn T, Polanczyk MJ, Borodovsky A, Ramanathapuram LV, Akporiaye ET, Ralph SJ. Use of anti-cancer drugs, mitocans, to enhance the immune responses against tumors. Curr Pharm Biotechnol 2013; 14:357-76. [PMID: 22201597 DOI: 10.2174/1389201011314030010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Revised: 09/02/2010] [Accepted: 09/17/2010] [Indexed: 12/12/2022]
Abstract
Cytotoxic drugs in cancer therapy are used with the expectation of selectively killing and thereby eliminating the offending cancer cells. If they should die in an appropriate manner, the cells can also release danger signals that promote an immune reaction that reinforces the response against the cancer. The identity of these immune-enhancing danger signals, how they work extra- and intracellularly, and the molecular mechanisms by which some anti-cancer drugs induce cell death to bring about the release of danger signals are the major focus of this review. A specific group of mitocans, the vitamin E analogs that act by targeting mitochondria to drive ROS production and also promote a more immunogenic means of cancer cell death exemplify such anti-cancer drugs. The role of reactive oxygen species (ROS) production and the events leading to the activation of the inflammasome and pro-inflammatory mediators induced by dying cancer cell mitochondria are discussed along with the evidence for their contribution to promoting immune responses against cancer. Current knowledge of how the danger signals interact with immune cells to boost the anti-tumor response is also evaluated.
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Affiliation(s)
- T Hahn
- School of Medical Sciences, Griffith Health Institute, Griffith University, Parklands Ave., Gold Coast, Queensland 4222, Australia
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771
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Maixner F, Overath T, Linke D, Janko M, Guerriero G, van den Berg BHJ, Stade B, Leidinger P, Backes C, Jaremek M, Kneissl B, Meder B, Franke A, Egarter-Vigl E, Meese E, Schwarz A, Tholey A, Zink A, Keller A. Paleoproteomic study of the Iceman's brain tissue. Cell Mol Life Sci 2013; 70:3709-22. [PMID: 23739949 PMCID: PMC11113858 DOI: 10.1007/s00018-013-1360-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 03/27/2013] [Accepted: 04/30/2013] [Indexed: 01/02/2023]
Abstract
The Tyrolean Iceman, a Copper-age ice mummy, is one of the best-studied human individuals. While the genome of the Iceman has largely been decoded, tissue-specific proteomes have not yet been investigated. We studied the proteome of two distinct brain samples using gel-based and liquid chromatography-mass spectrometry-based proteomics technologies together with a multiple-databases and -search algorithms-driven data-analysis approach. Thereby, we identified a total of 502 different proteins. Of these, 41 proteins are known to be highly abundant in brain tissue and 9 are even specifically expressed in the brain. Furthermore, we found 10 proteins related to blood and coagulation. An enrichment analysis revealed a significant accumulation of proteins related to stress response and wound healing. Together with atomic force microscope scans, indicating clustered blood cells, our data reopens former discussions about a possible injury of the Iceman's head near the site where the tissue samples have been extracted.
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Affiliation(s)
- Frank Maixner
- Institute for Mummies and the Iceman, EURAC research, 39100 Bolzano, Italy
| | - Thorsten Overath
- Division for Systematic Proteome Research, Institute for Experimental Medicine, Christian-Albrechts-Universität Kiel, 24105 Kiel, Germany
| | - Dennis Linke
- Division for Systematic Proteome Research, Institute for Experimental Medicine, Christian-Albrechts-Universität Kiel, 24105 Kiel, Germany
| | - Marek Janko
- Center of Smart Interfaces, TU Darmstadt, 64287 Darmstadt, Germany
| | - Gea Guerriero
- Department Environment and Agro-biotechnologies (EVA), Centre de Recherche Public-Gabriel Lippmann, 41, rue du Brill, 4422 Belvaux, Luxembourg
| | - Bart H. J. van den Berg
- Division for Systematic Proteome Research, Institute for Experimental Medicine, Christian-Albrechts-Universität Kiel, 24105 Kiel, Germany
| | - Bjoern Stade
- Institute of Clinical Molecular Biology, Christian-Albrechts-Universität Kiel, 24105 Kiel, Germany
| | - Petra Leidinger
- Department of Human Genetics, Saarland University, 66421 Saar Homburg, Germany
| | - Christina Backes
- Department of Human Genetics, Saarland University, 66421 Saar Homburg, Germany
| | | | - Benny Kneissl
- Software Engineering and Bioinformatics, Johannes Gutenberg-University of Mainz, 55128 Mainz, Germany
| | - Benjamin Meder
- Department of Internal Medicine III, University of Heidelberg, 69120 Heidelberg, Germany
| | - Andre Franke
- Institute of Clinical Molecular Biology, Christian-Albrechts-Universität Kiel, 24105 Kiel, Germany
| | - Eduard Egarter-Vigl
- Department of Pathological Anatomy and Histology, General Hospital Bolzano, 39100 Bolzano, Italy
| | - Eckart Meese
- Department of Human Genetics, Saarland University, 66421 Saar Homburg, Germany
| | - Andreas Schwarz
- Department of Neurosurgery, General Hospital Bolzano, 39100 Bolzano, Italy
| | - Andreas Tholey
- Division for Systematic Proteome Research, Institute for Experimental Medicine, Christian-Albrechts-Universität Kiel, 24105 Kiel, Germany
| | - Albert Zink
- Institute for Mummies and the Iceman, EURAC research, 39100 Bolzano, Italy
| | - Andreas Keller
- Department of Human Genetics, Saarland University, 66421 Saar Homburg, Germany
- Siemens Healthcare, 91052 Erlangen, Germany
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772
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Che XF, Moriya S, Zheng CL, Abe A, Tomoda A, Miyazawa K. 2-Aminophenoxazine-3-one-induced apoptosis via generation of reactive oxygen species followed by c-jun N-terminal kinase activation in the human glioblastoma cell line LN229. Int J Oncol 2013; 43:1456-66. [PMID: 24008433 DOI: 10.3892/ijo.2013.2088] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 08/02/2013] [Indexed: 11/06/2022] Open
Abstract
2-Aminophenoxazine-3-one (Phx-3) induces apoptosis in several types of cancer cell lines. However, the mechanism of apoptosis induction by Phx-3 has not been fully elucidated. In this study, we investigated the anticancer effects of Phx-3 in the glioblastoma cell line LN229 and analyzed its molecular mechanism. The results indicated that 6- and 20-h treatment with Phx-3 significantly induced apoptosis in LN229 cells, with downregulation of survivin and XIAP. Both ERK and JNK, which are the members of the MAPK family, were activated after treatment with Phx-3. Inhibition of ERK using the specific inhibitor U0126 blocked the Phx-3-induced apoptosis only in part. However, inhibition of JNK using the specific inhibitor SP600125 completely prevented Phx-3-induced apoptosis and restored the phosphorylation states of ERK to the control levels. Enhanced generation of reactive oxygen species (ROS) was detected after 3-h treatment with Phx-3. In addition, the ROS scavenger melatonin almost completely blocked Phx-3-induced JNK activation and apoptosis. This suggests that JNK activation was mediated by Phx-3-induced ROS generation. Although SP600125 and melatonin completely blocked the reduction of mitochondrial membrane potential after a 3-h treatment with Phx-3, extension of Phx-3 exposure time to 20 h resulted in no cancelation of mitochondrial depolarization by these reagents. These reagents also had little effect on the decreased expression of survivin and XIAP during a 3-20-h exposure to Phx-3. These results indicate that the production of ROS following JNK activation is the main axis of Phx-3-induced apoptosis in LN229 cells for short-term exposure to Phx-3, whereas alternative mechanism(s) appear to be involved in apoptosis induction during long-term exposure to Phx-3.
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Affiliation(s)
- Xiao-Fang Che
- Department of Biochemistry, Tokyo Medical University, Shinjuku-ku, Tokyo 160-8402, Japan
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773
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Sarangi U, Singh MK, Abhijnya KVV, Reddy LPA, Prasad BS, Pitke VV, Paithankar K, Sreedhar AS. Hsp60 chaperonin acts as barrier to pharmacologically induced oxidative stress mediated apoptosis in tumor cells with differential stress response. Drug Target Insights 2013; 7:35-51. [PMID: 24027419 PMCID: PMC3767580 DOI: 10.4137/dti.s12513] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Mitochondrial functions play a central role in energy metabolism and provide survival fitness to both normal and tumor cells. Mitochondrial chaperonin Hsp60 is involved in both pro- and anti-apoptotic functions, but how Hsp60 senses the mitochondria selective oxidative stress response is unknown. In this study, by using rotenone, an irreversible inhibitor of oxidative phosphorylation against IMR-32 and BC-8 tumor cells containing differential heat shock transcriptional machinery, we studied whether the oxidative stress response is related to Hsp60. The accelerated cytotoxicity in response to rotenone has been correlated with enhanced production of O2 (•-), H2O2, reactive oxygen species, and Hsp60 translocation from the mitochondria to the cytoplasm. The inability of cells to resist oxidative stress mediated Hsp60 translocation appeared to depend on mitochondrial oxyradical scavenging system and Bax translocation. A delayed oxidative stress response in hsp60 shRNA-treated cells was found to be due to increased mitochondrial translocation of Hsp60 on shRNA pre-sensitization. Overexpression of Hsp60 failed to protect cells from oxidative stress due to a lack of its mitochondrial retention upon post-rotenone treatment. These results also revealed that Hsp60 mitochondrial localization is indispensable for decreasing O2 (•-) levels, but not H2O2 and ROS levels. However, cycloheximide treatment alone induced Hsp60 translocation, while rotenone combination delayed this translocation. In contrast to oxidative stress, MG132 and 17AAG treatments showed mitochondrial retention of Hsp60; however, MG132 combination either with hsp60 shRNA or 17AAG induced its translocation. Additionally, overexpression of Huntingtin gene also resulted in Hsp60 mitochondrial accumulation. We suggest that Hsp60 may act as a barrier to pharmacological targeting of mitochondria.
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Affiliation(s)
- Upasana Sarangi
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, Andhra Pradesh, India
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774
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Muralidharan S, Mandrekar P. Cellular stress response and innate immune signaling: integrating pathways in host defense and inflammation. J Leukoc Biol 2013; 94:1167-84. [PMID: 23990626 DOI: 10.1189/jlb.0313153] [Citation(s) in RCA: 212] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Extensive research in the past decade has identified innate immune recognition receptors and intracellular signaling pathways that culminate in inflammatory responses. Besides its role in cytoprotection, the importance of cell stress in inflammation and host defense against pathogens is emerging. Recent studies have shown that proteins in cellular stress responses, including the heat shock response, ER stress response, and DNA damage response, interact with and regulate signaling intermediates involved in the activation of innate and adaptive immune responses. The effect of such regulation by cell stress proteins may dictate the inflammatory profile of the immune response during infection and disease. In this review, we describe the regulation of innate immune cell activation by cell stress pathways, present detailed descriptions of the types of stress response proteins and their crosstalk with immune signaling intermediates that are essential in host defense, and illustrate the relevance of these interactions in diseases characteristic of aberrant immune responses, such as chronic inflammatory diseases, autoimmune disorders, and cancer. Understanding the crosstalk between cellular stress proteins and immune signaling may have translational implications for designing more effective regimens to treat immune disorders.
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Affiliation(s)
- Sujatha Muralidharan
- 1.LRB 221, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605.
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775
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Li G, Tang D, Lotze MT. Ménage à Trois in stress: DAMPs, redox and autophagy. Semin Cancer Biol 2013; 23:380-90. [PMID: 23994764 DOI: 10.1016/j.semcancer.2013.08.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 08/08/2013] [Accepted: 08/20/2013] [Indexed: 12/30/2022]
Abstract
Cells have evolved rather sophisticated mechanisms to deal with stress positively and efficiently. Accumulation of reactive oxygen species (ROS), release of damage-associated molecular pattern molecule (DAMPs), and autophagy induction, are three inter-related processes occurring during most if not all cellular adaptations to stress. They influence each other reciprocally, initiating individual pathways, mediating and/or inducing effector mechanisms and modifying cellular function. High-mobility group box 1 (HMGB1), is a prototypic DAMP molecule, with various roles depending on its compartmental localization (nuclear, cytosolic, extracellular), well-defined but rather promiscuous binding partners, and the redox status within or without the cell. Typically, HMGB1 serves as a redox sensor, where redox modification also defines its translocation, release and activity, illustrative of the coordinate and multiply determined paths involved in the response to cell stress. Since DAMPs, redox and autophagy are essential and multifaceted in their roles in host defense, inflammation, and homeostasis, understanding how they interact and coordinate various signaling pathways to adjust to the stressful environment is important in the development of various potential therapeutic strategies, including application to patients with cancer.
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Affiliation(s)
- Guanqiao Li
- Department of Surgery, University of Pittsburgh School of Medicine and the University of Pittsburgh Cancer Institute, United States; Department of Immunology, University of Pittsburgh School of Medicine and the University of Pittsburgh Cancer Institute, United States; Tsinghua University, School of Medicine, Beijing, China
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776
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Strozyk E, Kulms D. The role of AKT/mTOR pathway in stress response to UV-irradiation: implication in skin carcinogenesis by regulation of apoptosis, autophagy and senescence. Int J Mol Sci 2013; 14:15260-85. [PMID: 23887651 PMCID: PMC3759859 DOI: 10.3390/ijms140815260] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Revised: 06/27/2013] [Accepted: 07/01/2013] [Indexed: 02/06/2023] Open
Abstract
Induction of DNA damage by UVB and UVA radiation may generate mutations and genomic instability leading to carcinogenesis. Therefore, skin cells being repeatedly exposed to ultraviolet (UV) light have acquired multilayered protective mechanisms to avoid malignant transformation. Besides extensive DNA repair mechanisms, the damaged skin cells can be eliminated by induction of apoptosis, which is mediated through the action of tumor suppressor p53. In order to prevent the excessive loss of skin cells and to maintain the skin barrier function, apoptotic pathways are counteracted by anti-apoptotic signaling including the AKT/mTOR pathway. However, AKT/mTOR not only prevents cell death, but is also active in cell cycle transition and hyper-proliferation, thereby also counteracting p53. In turn, AKT/mTOR is tuned down by the negative regulators being controlled by the p53. This inhibition of AKT/mTOR, in combination with transactivation of damage-regulated autophagy modulators, guides the p53-mediated elimination of damaged cellular components by autophagic clearance. Alternatively, p53 irreversibly blocks cell cycle progression to prevent AKT/mTOR-driven proliferation, thereby inducing premature senescence. Conclusively, AKT/mTOR via an extensive cross talk with p53 influences the UV response in the skin with no black and white scenario deciding over death or survival.
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Affiliation(s)
- Elwira Strozyk
- Experimental Dermatology, Department of Dermatology, TU Dresden, 01307 Dresden, Germany; E-Mail:
| | - Dagmar Kulms
- Experimental Dermatology, Department of Dermatology, TU Dresden, 01307 Dresden, Germany; E-Mail:
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777
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Dai CL, Shi J, Chen Y, Iqbal K, Liu F, Gong CX. Inhibition of protein synthesis alters protein degradation through activation of protein kinase B (AKT). J Biol Chem 2013; 288:23875-83. [PMID: 23843462 DOI: 10.1074/jbc.m112.445148] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The homeostasis of protein metabolism is maintained and regulated by the rates of protein biosynthesis and degradation in living systems. Alterations of protein degradation may regulate protein biosynthesis through a feedback mechanism. Whether a change in protein biosynthesis modulates protein degradation has not been reported. In this study, we found that inhibition of protein biosynthesis induced phosphorylation/activation of AKT and led to phosphorylation of AKT target substrates, including FoxO1, GSK3α/β, p70S6K, AS160, and the E3 ubiquitin ligase MDM2. Phosphorylation of ribosomal protein S6 was also modulated by inhibition of protein biosynthesis. The AKT phosphorylation/activation was mediated mainly through the PI3K pathway because it was blocked by the PI3K inhibitor LY294002. The activated AKT phosphorylated MDM2 at Ser(166) and promoted degradation of the tumor suppressor p53. These findings suggest that inhibition of protein biosynthesis can alter degradation of some proteins through activation of AKT. This study reveals a novel regulation of protein degradation and calls for caution in blocking protein biosynthesis to study the half-life of proteins.
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Affiliation(s)
- Chun-Ling Dai
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York 10314, USA
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778
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Ghosh R, Guha D, Bhowmik S, Karmakar S. Antioxidant enzymes and the mechanism of the bystander effect induced by ultraviolet C irradiation of A375 human melanoma cells. Mutat Res 2013; 757:83-90. [PMID: 23845763 DOI: 10.1016/j.mrgentox.2013.06.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 06/12/2013] [Accepted: 06/30/2013] [Indexed: 11/30/2022]
Abstract
Irradiated cells generate dynamic responses in non-irradiated cells; this signaling phenomenon is known as the bystander effect (BE). Factors secreted by the irradiated cells communicate some of these signals. Conditioned medium from UVC-irradiated A375 human melanoma cells was used to study the BE. Exposure of cells to conditioned medium induce cell-cycle arrest at the G2/M transition. Although conditioned medium treatment, by itself, did not alter cell viability, treated cells were more resistant to the lethal action of UVC or H2O2. This protective effect of conditioned medium was lost within 8h. Apoptotic or autophagic cell death was not involved in this resistance. Exposure to conditioned medium did not influence the rate of DNA repair, as measured by NAD(+) depletion. The activities of catalase and superoxide dismutase were elevated in cells exposed to conditioned medium, but returned to normal levels by 8h post-treatment. These results indicate a close correlation between BE-stimulated antioxidant activity and cellular sensitivity. Cell-cycle arrest and stimulation of antioxidant activity may account for the resistance to killing that was observed in bystander cells exposed to UVC or H2O2 treatment and are consistent with the role of the BE as a natural defense function triggered by UVC irradiation.
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Affiliation(s)
- Rita Ghosh
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani 741235, West Bengal, India.
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779
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Mao L, Franke J. Hormesis in aging and neurodegeneration-a prodigy awaiting dissection. Int J Mol Sci 2013; 14:13109-28. [PMID: 23799363 PMCID: PMC3742177 DOI: 10.3390/ijms140713109] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 05/16/2013] [Accepted: 05/17/2013] [Indexed: 12/17/2022] Open
Abstract
Hormesis describes the drug action of low dose stimulation and high dose inhibition. The hormesis phenomenon has been observed in a wide range of biological systems. Although known in its descriptive context, the underlying mode-of-action of hormesis is largely unexplored. Recently, the hormesis concept has been receiving increasing attention in the field of aging research. It has been proposed that within a certain concentration window, reactive oxygen species (ROS) or reactive nitrogen species (RNS) could act as major mediators of anti-aging and neuroprotective processes. Such hormetic phenomena could have potential therapeutic applications, if properly employed. Here, we review the current theories of hormetic phenomena in regard to aging and neurodegeneration, with the focus on its underlying mechanism. Facilitated by a simple mathematical model, we show for the first time that ROS-mediated hormesis can be explained by the addition of different biomolecular reactions including oxidative damage, MAPK signaling and autophagy stimulation. Due to their divergent scales, the optimal hormetic window is sensitive to each kinetic parameter, which may vary between individuals. Therefore, therapeutic utilization of hormesis requires quantitative characterizations in order to access the optimal hormetic window for each individual. This calls for a personalized medicine approach for a longer human healthspan.
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Affiliation(s)
- Lei Mao
- Department of Life Science Engineering, HTW Berlin, University of Applied Sciences, Wilhelminenhofstraße 75A, Berlin 12459, Germany; E-Mail:
- Institute of Medical Genetics and Human Genetics, Charité—Universitätsmedizin Berlin, Augustenbruger Platz 1, Berlin 13353, Germany
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +49-30-5019-3616; Fax: +49-30-5019-3648
| | - Jacqueline Franke
- Department of Life Science Engineering, HTW Berlin, University of Applied Sciences, Wilhelminenhofstraße 75A, Berlin 12459, Germany; E-Mail:
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780
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Overexpression of Lon contributes to survival and aggressive phenotype of cancer cells through mitochondrial complex I-mediated generation of reactive oxygen species. Cell Death Dis 2013; 4:e681. [PMID: 23788038 PMCID: PMC3702277 DOI: 10.1038/cddis.2013.204] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Lon protease is a multifunction protein and operates in protein quality control and stress response pathways in mitochondria. Human Lon is upregulated under oxidative and hypoxic stresses that represent the stress phenotypes of cancer. However, little literature undertakes comprehensive and detailed investigations on the tumorigenic role of Lon. Overexpression of Lon promotes cell proliferation, apoptotic resistance to stresses, and transformation. Furthermore, Lon overexpression induces the production of mitochondrial reactive oxygen species (ROS) that result from Lon-mediated upregulation of NDUFS8, a mitochondrial Fe-S protein in complex I of electron transport chain. Increased level of mitochondrial ROS promotes cell proliferation, cell survival, cell migration, and epithelial–mesenchymal transition through mitogen-activated protein kinase (MAPK) and Ras-ERK activation. Overall, the present report for the first time demonstrates the role of Lon overexpression in tumorigenesis. Lon overexpression gives an apoptotic resistance to stresses and induces mitochondrial ROS production through Complex I as signaling molecules to activate Ras and MAPK signaling, giving the survival advantages and adaptation to cancer cells. Finally, in silico and immunohistochemistry analysis showed that Lon is overexpressed specifically in various types of cancer tissue including oral cancer.
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781
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Heneidi S, Simerman AA, Keller E, Singh P, Li X, Dumesic DA, Chazenbalk G. Awakened by cellular stress: isolation and characterization of a novel population of pluripotent stem cells derived from human adipose tissue. PLoS One 2013; 8:e64752. [PMID: 23755141 PMCID: PMC3673968 DOI: 10.1371/journal.pone.0064752] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 04/17/2013] [Indexed: 12/15/2022] Open
Abstract
Advances in stem cell therapy face major clinical limitations, particularly challenged by low rates of post-transplant cell survival. Hostile host factors of the engraftment microenvironment such as hypoxia, nutrition deprivation, pro-inflammatory cytokines, and reactive oxygen species can each contribute to unwanted differentiation or apoptosis. In this report, we describe the isolation and characterization of a new population of adipose tissue (AT) derived pluripotent stem cells, termed Multilineage Differentiating Stress-Enduring (Muse) Cells, which are isolated using severe cellular stress conditions, including long-term exposure to the proteolytic enzyme collagenase, serum deprivation, low temperatures and hypoxia. Under these conditions, a highly purified population of Muse-AT cells is isolated without the utilization of cell sorting methods. Muse-AT cells grow in suspension as cell spheres reminiscent of embryonic stem cell clusters. Muse-AT cells are positive for the pluripotency markers SSEA3, TR-1-60, Oct3/4, Nanog and Sox2, and can spontaneously differentiate into mesenchymal, endodermal and ectodermal cell lineages with an efficiency of 23%, 20% and 22%, respectively. When using specific differentiation media, differentiation efficiency is greatly enhanced in Muse-AT cells (82% for mesenchymal, 75% for endodermal and 78% for ectodermal). When compared to adipose stem cells (ASCs), microarray data indicate a substantial up-regulation of Sox2, Oct3/4, and Rex1. Muse-ATs also exhibit gene expression patterns associated with the down-regulation of genes involved in cell death and survival, embryonic development, DNA replication and repair, cell cycle and potential factors related to oncogenecity. Gene expression analysis indicates that Muse-ATs and ASCs are mesenchymal in origin; however, Muse-ATs also express numerous lymphocytic and hematopoietic genes, such as CCR1 and CXCL2, encoding chemokine receptors and ligands involved in stem cell homing. Being highly resistant to severe cellular stress, Muse-AT cells have the potential to make a critical impact on the field of regenerative medicine and cell-based therapy.
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Affiliation(s)
- Saleh Heneidi
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, District of Columbia, United States of America
| | - Ariel A. Simerman
- Department of Obstetrics and Gynecology, David Geffen School of Medicine at University of Los Angeles, Los Angeles, California, United States of America
| | - Erica Keller
- Department of Obstetrics and Gynecology, David Geffen School of Medicine at University of Los Angeles, Los Angeles, California, United States of America
| | - Prapti Singh
- Department of Obstetrics and Gynecology, David Geffen School of Medicine at University of Los Angeles, Los Angeles, California, United States of America
| | - Xinmin Li
- Clinical Microarray Core, David Geffen School of Medicine at University of Los Angeles, Los Angeles, California, United States of America
| | - Daniel A. Dumesic
- Department of Obstetrics and Gynecology, David Geffen School of Medicine at University of Los Angeles, Los Angeles, California, United States of America
| | - Gregorio Chazenbalk
- Department of Obstetrics and Gynecology, David Geffen School of Medicine at University of Los Angeles, Los Angeles, California, United States of America
- * E-mail:
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782
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Abstract
Secretion of growth hormone (GH), and consequently that of insulin-like growth factor 1 (IGF-1), declines over time until only low levels can be detected in individuals aged ≥60 years. This phenomenon, which is known as the 'somatopause', has led to recombinant human GH being widely promoted and abused as an antiageing drug, despite lack of evidence of efficacy. By contrast, several mutations that decrease the tone of the GH/IGF-1 axis are associated with extended longevity in mice. In humans, corresponding or similar mutations have been identified, but whether these mutations alter longevity has yet to be established. The powerful effect of reduced GH activity on lifespan extension in mice has generated the hypothesis that pharmaceutically inhibiting, rather than increasing, GH action might delay ageing. Moreover, mice as well as humans with reduced activity of the GH/IGF-1 axis are protected from cancer and diabetes mellitus, two major ageing-related morbidities. Here, we review data on mouse strains with alterations in the GH/IGF-1 axis and their effects on lifespan. The outcome of corresponding or similar mutations in humans is described, as well as the potential mechanisms underlying increased longevity and the therapeutic benefits and risks of medical disruption of the GH/IGF-1 axis in humans.
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Affiliation(s)
- Riia K Junnila
- Edison Biotechnology Institute, Ohio University, 1 Water Tower Drive, The Ridges (R. K. Junnila, E. O. List, D. E. Berryman, J. J. Kopchick), Department of Radiology, O'Bleness Hospital, 55 Hospital Drive, (J. W. Murrey), Athens, OH 45701, USA
| | - Edward O List
- Edison Biotechnology Institute, Ohio University, 1 Water Tower Drive, The Ridges (R. K. Junnila, E. O. List, D. E. Berryman, J. J. Kopchick), Department of Radiology, O'Bleness Hospital, 55 Hospital Drive, (J. W. Murrey), Athens, OH 45701, USA
| | - Darlene E Berryman
- Edison Biotechnology Institute, Ohio University, 1 Water Tower Drive, The Ridges (R. K. Junnila, E. O. List, D. E. Berryman, J. J. Kopchick), Department of Radiology, O'Bleness Hospital, 55 Hospital Drive, (J. W. Murrey), Athens, OH 45701, USA
| | - John W Murrey
- Edison Biotechnology Institute, Ohio University, 1 Water Tower Drive, The Ridges (R. K. Junnila, E. O. List, D. E. Berryman, J. J. Kopchick), Department of Radiology, O'Bleness Hospital, 55 Hospital Drive, (J. W. Murrey), Athens, OH 45701, USA
| | - John J Kopchick
- Edison Biotechnology Institute, Ohio University, 1 Water Tower Drive, The Ridges (R. K. Junnila, E. O. List, D. E. Berryman, J. J. Kopchick), Department of Radiology, O'Bleness Hospital, 55 Hospital Drive, (J. W. Murrey), Athens, OH 45701, USA
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783
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Grapsa D, Frangou-Plemenou M, Kondi-Pafiti A, Stergiou E, Nicolopoulou-Stamati P, Patsouris E, Chelidonis G, Athanassiadou P. “Immunocytochemical expression of P53, PTEN, FAS (CD95), P16INK4A and HPV L1 major capsid proteins in ThinPrep cervical samples with squamous intraepithelial lesions”. Diagn Cytopathol 2013; 42:465-75. [DOI: 10.1002/dc.23003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 04/03/2013] [Indexed: 01/24/2023]
Affiliation(s)
- D. Grapsa
- Cytopathology Department; LAIKO Athens General Hospital; Athens Greece
| | | | - A. Kondi-Pafiti
- Pathology LaboratorycAreteion Hospital; University of Athens; Athens Greece
| | - E. Stergiou
- Cytopathology Department; LAIKO Athens General Hospital; Athens Greece
| | | | - E. Patsouris
- Pathology Laboratory; Medical School; University of Athens; Athens Greece
| | - G. Chelidonis
- Pathology Laboratory; Medical School; University of Athens; Athens Greece
| | - P. Athanassiadou
- Pathology Laboratory; Medical School; University of Athens; Athens Greece
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784
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Giannattasio S, Guaragnella N, Arbini AA, Moro L. Stress-related mitochondrial components and mitochondrial genome as targets of anticancer therapy. Chem Biol Drug Des 2013; 81:102-12. [PMID: 23253132 DOI: 10.1111/cbdd.12057] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In addition to their role as cell powerhouse mitochondria are key organelles in the processes deciding about cell life or death that are crucial for tumor cell growth and survival, as well as for tumor cell ability to metastasize. Alterations in mitochondrial structure and functions have long been observed in cancer cells, thus targeting mitochondria as an anticancer therapeutic strategy has gained momentum recently. We will review the achievements and perspectives in the elucidation of the molecular basis for developing mitochondrial-targeted compounds as potential anticancer agents with special attention to mitochondrial DNA mutations and mitochondrial dysfunction. Molecules/agents candidate to affect mitochondrial metabolism in cancer cells will be dealt with, with a particular focus on approaches targeting defects in the mitochondrial genome.
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Affiliation(s)
- Sergio Giannattasio
- Institute of Biomembranes and Bioenergetics, National Research Council, Via Amendola 165/a, 70126 Bari, Italy.
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785
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Loganathan R, Selvaduray KR, Nesaretnam K, Radhakrishnan AK. Tocotrienols promote apoptosis in human breast cancer cells by inducing poly(ADP-ribose) polymerase cleavage and inhibiting nuclear factor kappa-B activity. Cell Prolif 2013; 46:203-13. [PMID: 23510475 DOI: 10.1111/cpr.12014] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 10/02/2012] [Accepted: 10/19/2012] [Indexed: 12/26/2022] Open
Abstract
OBJECTIVES Tocotrienols and tocopherols are members of the vitamin E family, with similar structures; however, only tocotrienols have been reported to achieve potent anti-cancer effects. The study described here has evaluated anti-cancer activity of vitamin E to elucidate mechanisms of cell death, using human breast cancer cells. MATERIALS AND METHODS Anti-cancer activity of a tocotrienol-rich fraction (TRF) and a tocotrienol-enriched fraction (TEF) isolated from palm oil, as well as pure vitamin E analogues (α-tocopherol, α-, δ- and γ-tocotrienols) were studied using highly aggressive triple negative MDA-MB-231 cells and oestrogen-dependent MCF-7 cells, both of human breast cancer cell lines. Cell population growth was evaluated using a Coulter particle counter. Cell death mechanism, poly(ADP-ribose) polymerase cleavage and levels of NF-κB were determined using commercial ELISA kits. RESULTS Tocotrienols exerted potent anti-proliferative effects on both types of cell by inducing apoptosis, the underlying mechanism of cell death being ascertained using respective IC50 concentrations of all test compounds. There was marked induction of apoptosis in both cell lines by tocotrienols compared to treatment with Paclitaxel, which was used as positive control. This activity was found to be associated with cleavage of poly(ADP-ribose) polymerase (a DNA repair protein), demonstrating involvement of the apoptotic cell death signalling pathway. Tocotrienols also inhibited expression of nuclear factor kappa-B (NF-κB), which in turn can increase sensitivity of cancer cells to apoptosis. CONCLUSION Tocotrienols induced anti-proliferative and apoptotic effects in association with DNA fragmentation, poly(ADP-ribose) polymerase cleavage and NF-κB inhibition in the two human breast cancer cell lines.
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Affiliation(s)
- R Loganathan
- Malaysian Palm Oil Board, Selangor, 43000, Malaysia
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786
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Kucharzewska P, Belting M. Emerging roles of extracellular vesicles in the adaptive response of tumour cells to microenvironmental stress. J Extracell Vesicles 2013; 2:20304. [PMID: 24009895 PMCID: PMC3760648 DOI: 10.3402/jev.v2i0.20304] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 01/09/2013] [Accepted: 02/01/2013] [Indexed: 12/20/2022] Open
Abstract
Cells are constantly subjected to various types of endogenous and exogenous stressful stimuli, which can cause serious and even permanent damage. The ability of a cell to sense and adapt to environmental alterations is thus vital to maintain tissue homeostasis during development and adult life. Here, we review some of the major phenotypic characteristics of the hostile tumour microenvironment and the emerging roles of extracellular vesicles in these events.
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Affiliation(s)
- Paulina Kucharzewska
- Section of Oncology, Department of Clinical Sciences, Lund University, Lund, Sweden
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787
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Zhang Q, Kang R, Zeh HJ, Lotze MT, Tang D. DAMPs and autophagy: cellular adaptation to injury and unscheduled cell death. Autophagy 2013; 9:451-8. [PMID: 23388380 DOI: 10.4161/auto.23691] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Autophagy is a lysosome-mediated catabolic process involving the degradation of intracellular contents (e.g., proteins and organelles) as well as invading microbes (e.g., parasites, bacteria and viruses). Multiple forms of cellular stress can stimulate this pathway, including nutritional imbalances, oxygen deprivation, immunological response, genetic defects, chromosomal anomalies and cytotoxic stress. Damage-associated molecular pattern molecules (DAMPs) are released by stressed cells undergoing autophagy or injury, and act as endogenous danger signals to regulate the subsequent inflammatory and immune response. A complex relationship exists between DAMPs and autophagy in cellular adaption to injury and unscheduled cell death. Since both autophagy and DAMPs are important for pathogenesis of human disease, it is crucial to understand how they interplay to sustain homeostasis in stressful or dangerous environments.
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Affiliation(s)
- Qiuhong Zhang
- Department of Surgery, University of Pittsburgh Cancer Institute, University of Pittsburgh, Pittsburgh, PA, USA
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788
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Chhangani D, Mishra A. Protein quality control system in neurodegeneration: a healing company hard to beat but failure is fatal. Mol Neurobiol 2013; 48:141-56. [PMID: 23378031 DOI: 10.1007/s12035-013-8411-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 01/17/2013] [Indexed: 01/10/2023]
Abstract
A common feature in most neurodegenerative diseases and aging is the progressive accumulation of damaged proteins. Proteins are essential for all crucial biological functions. Under some notorious conditions, proteins loss their three dimensional native conformations and are converted into disordered aggregated structures. Such changes rise into pathological conditions and eventually cause serious protein conformation disorders. Protein aggregation and inclusion bodies formation mediated multifactorial proteotoxic stress has been reported in the progression of Parkinson's disease (PD), Huntington's disease (HD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS) and Prion disease. Ongoing studies have been remarkably informative in providing a systematic outlook for better understanding the concept and fundamentals of protein misfolding and aggregations. However, the precise role of protein quality control system and precursors of this mechanism remains elusive. In this review, we highlight recent insights and discuss emerging cytoprotective strategies of cellular protein quality control system implicated in protein deposition diseases. Our current review provides a clear, understandable framework of protein quality control system that may offer the more suitable therapeutic strategies for protein-associated diseases.
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Affiliation(s)
- Deepak Chhangani
- Cellular and Molecular Neurobiology Laboratory, Indian Institute of Technology, Jodhpur, Rajasthan, 342011, India
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789
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Takeda K. Mitochondrial DNA transmission and confounding mitochondrial influences in cloned cattle and pigs. Reprod Med Biol 2013; 12:47-55. [PMID: 29699130 DOI: 10.1007/s12522-012-0142-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 12/21/2012] [Indexed: 01/05/2023] Open
Abstract
Although somatic cell nuclear transfer (SCNT) is a powerful tool for production of cloned animals, SCNT embryos generally have low developmental competency and many abnormalities. The interaction between the donor nucleus and the enucleated ooplasm plays an important role in early embryonic development, but the underlying mechanisms that negatively impact developmental competency remain unclear. Mitochondria have a broad range of critical functions in cellular energy supply, cell signaling, and programmed cell death; thus, affect embryonic and fetal development. This review focuses on mitochondrial considerations influencing SCNT techniques in farm animals. Donor somatic cell mitochondrial DNA (mtDNA) can be transmitted through what has been considered a "bottleneck" in mitochondrial genetics via the SCNT maternal lineage. This indicates that donor somatic cell mitochondria have a role in the reconstructed cytoplasm. However, foreign somatic cell mitochondria may affect the early development of SCNT embryos. Nuclear-mitochondrial interactions in interspecies/intergeneric SCNT (iSCNT) result in severe problems. A major biological selective pressure exists against survival of exogenous mtDNA in iSCNT. Yet, mtDNA differences in SCNT animals did not reflect transfer of proteomic components following proteomic analysis. Further study of nuclear-cytoplasmic interactions is needed to illuminate key developmental characteristics of SCNT animals associated with mitochondrial biology.
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Affiliation(s)
- Kumiko Takeda
- NARO Institute of Livestock and Grassland Science National Agriculture and Food Research Organization 2 Ikenodai 305-0901 Tsukuba Japan
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790
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Kay M, Hojati Z, Dehghanian F. The molecular study of IFNβ pleiotropic roles in MS treatment. IRANIAN JOURNAL OF NEUROLOGY 2013; 12:149-56. [PMID: 24250925 PMCID: PMC3829308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 06/08/2013] [Indexed: 11/23/2022]
Abstract
Multiple sclerosis (MS) is one of the most important autoimmune diseases recognized by demyelination and axonal lesion. It is the most common cause of disability in the young population. Various immunomodulatory and immunosuppressive therapies, including different formulations of interferon beta (IFNβ), glatiramer acetate (GA), mitoxantrone, and natalizumab are available for this disease. However, interferon has been the best prescribed. Although the precise mechanism of IFNβ is unclear, many studies indicate some potential mechanism including blocking T cells activation, controlling pro- and anti-inflammatory cytokine secretion, preventing activated immune cell migration through BBB, and inducing repair activity of damaged nerve cells by differentiating neural stem cells into oligodendrocytes. These molecular mechanisms have significant roles in IFNβ therapy. More researches are required in order for us to comprehend the mechanism of action of IFNβ, and improve and develop drugs for more efficient MS treatment.
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Affiliation(s)
- Maryam Kay
- MSc Student, Department of Biology, School of Sciences, University of Isfahan, Isfahan, Iran
| | - Zohreh Hojati
- Assistant Professor, Department of Biology, School of Sciences, University of Isfahan, Isfahan, Iran
| | - Fariba Dehghanian
- MSc Student, Department of Biology, School of Sciences, University of Isfahan, Isfahan, Iran
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791
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Adaptive and Pathogenic Responses to Stress by Stem Cells during Development. Cells 2012; 1:1197-224. [PMID: 24710551 PMCID: PMC3901130 DOI: 10.3390/cells1041197] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Revised: 11/06/2012] [Accepted: 11/07/2012] [Indexed: 02/07/2023] Open
Abstract
Cellular stress is the basis of a dose-dependent continuum of responses leading to adaptive health or pathogenesis. For all cells, stress leads to reduction in macromolecular synthesis by shared pathways and tissue and stress-specific homeostatic mechanisms. For stem cells during embryonic, fetal, and placental development, higher exposures of stress lead to decreased anabolism, macromolecular synthesis and cell proliferation. Coupled with diminished stem cell proliferation is a stress-induced differentiation which generates minimal necessary function by producing more differentiated product/cell. This compensatory differentiation is accompanied by a second strategy to insure organismal survival as multipotent and pluripotent stem cells differentiate into the lineages in their repertoire. During stressed differentiation, the first lineage in the repertoire is increased and later lineages are suppressed, thus prioritized differentiation occurs. Compensatory and prioritized differentiation is regulated by at least two types of stress enzymes. AMP-activated protein kinase (AMPK) which mediates loss of nuclear potency factors and stress-activated protein kinase (SAPK) that does not. SAPK mediates an increase in the first essential lineage and decreases in later lineages in placental stem cells. The clinical significance of compensatory and prioritized differentiation is that stem cell pools are depleted and imbalanced differentiation leads to gestational diseases and long term postnatal pathologies.
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792
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von Schwarzenberg K, Wiedmann RM, Oak P, Schulz S, Zischka H, Wanner G, Efferth T, Trauner D, Vollmar AM. Mode of cell death induction by pharmacological vacuolar H+-ATPase (V-ATPase) inhibition. J Biol Chem 2012; 288:1385-96. [PMID: 23168408 DOI: 10.1074/jbc.m112.412007] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The vacuolar H(+)-ATPase (V-ATPase), a multisubunit proton pump, has come into focus as an attractive target in cancer invasion. However, little is known about the role of V-ATPase in cell death, and especially the underlying mechanisms remain mostly unknown. We used the myxobacterial macrolide archazolid B, a potent inhibitor of the V-ATPase, as an experimental drug as well as a chemical tool to decipher V-ATPase-related cell death signaling. We found that archazolid induced apoptosis in highly invasive tumor cells at nanomolar concentrations which was executed by the mitochondrial pathway. Prior to apoptosis induction archazolid led to the activation of a cellular stress response including activation of the hypoxia-inducible factor-1α (HIF1α) and autophagy. Autophagy, which was demonstrated by degradation of p62 or fusion of autophagosomes with lysosomes, was induced at low concentrations of archazolid that not yet increase pH in lysosomes. HIF1α was induced due to energy stress shown by a decline of the ATP level and followed by a shutdown of energy-consuming processes. As silencing HIF1α increases apoptosis, the cellular stress response was suggested to be a survival mechanism. We conclude that archazolid leads to energy stress which activates adaptive mechanisms like autophagy mediated by HIF1α and finally leads to apoptosis. We propose V-ATPase as a promising drugable target in cancer therapy caught up at the interplay of apoptosis, autophagy, and cellular/metabolic stress.
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Affiliation(s)
- Karin von Schwarzenberg
- Department of Pharmacy, Pharmaceutical Biology, Ludwig-Maximilians-University, 81377 Munich, Germany.
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793
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Identification and functional analysis of the novel ORF4 protein encoded by porcine circovirus type 2. J Virol 2012; 87:1420-9. [PMID: 23152517 DOI: 10.1128/jvi.01443-12] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Porcine circovirus type 2 (PCV2) is the primary causative agent of porcine circovirus-associated diseases in pigs. To date, viral proteins Cap, Rep, Rep', and ORF3, encoded by the PCV2 genome, have been described. Here, transcription and translation of a novel viral gene within the PCV2 genome (designated ORF4) was determined and functionally analyzed in vitro and in vivo. Northern blot analysis indicated that the RNA transcribed from the ORF4 gene is about 180 bp in length and overlaps ORF3 in the same direction. Site-directed mutagenesis confirmed that the viral ORF4 protein is not essential for virus replication in PK-15 cells and in mice infected with an ORF4-deficient PCV2 (PCV2Δ). PCV2Δ triggered higher activity levels of caspase-3 and -8 than wild-type PCV2 (wPCV2) in PK-15 cells. The antigenic epitopes of two mouse monoclonal antibodies (MAbs) raised against the viral ORF4 protein were mapped to the same 19KSSASPR25 peptide. Expression of ORF4 was confirmed using the specific MAbs in wPCV2-infected PK-15 cells and mice. Mice infected with PCV2Δ had a higher serum viral load (genomic copies) and more severe lymphoid tissue damage in the spleen than those infected with wPCV2. Meanwhile, flow-cytometric analysis indicated that the PCV2Δ infection caused a significant decrease of CD4(+) and CD8(+) T lymphocytes. Our results demonstrate that ORF4 is a newly discovered viral protein that is not essential for PCV2 replication but plays a role in suppressing caspase activity and regulating CD4(+) and CD8(+) T lymphocytes during PCV2 infection.
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794
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Adaptive response, evidence of cross-resistance and its potential clinical use. Int J Mol Sci 2012; 13:10771-10806. [PMID: 23109822 PMCID: PMC3472714 DOI: 10.3390/ijms130910771] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/07/2012] [Accepted: 08/13/2012] [Indexed: 12/15/2022] Open
Abstract
Organisms and their cells are constantly exposed to environmental fluctuations. Among them are stressors, which can induce macromolecular damage that exceeds a set threshold, independent of the underlying cause. Stress responses are mechanisms used by organisms to adapt to and overcome stress stimuli. Different stressors or different intensities of stress trigger different cellular responses, namely induce cell repair mechanisms, induce cell responses that result in temporary adaptation to some stressors, induce autophagy or trigger cell death. Studies have reported life-prolonging effects of a wide variety of so-called stressors, such as oxidants, heat shock, some phytochemicals, ischemia, exercise and dietary energy restriction, hypergravity, etc. These stress responses, which result in enhanced defense and repair and even cross-resistance against multiple stressors, may have clinical use and will be discussed, while the emphasis will be on the effects/cross-effects of oxidants.
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795
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Bongiorno VA, Ferreira da Cruz A, Nunis da Silva A, Corrêa LC. Phosphate limitation induces sporulation in the chytridiomycete Blastocladiella emersonii. Can J Microbiol 2012; 58:1104-11. [PMID: 22913304 DOI: 10.1139/w2012-090] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The cell cycle is controlled by numerous mechanisms that ensure correct cell division. If growth is not possible, cells may eventually promote autophagy, differentiation, or apoptosis. Microorganisms interrupt their growth and differentiate under general nutrient limitation. We analyzed the effects of phosphate limitation on growth and sporulation in the chytridiomycete Blastocladiella emersonii using kinetic data, phase-contrast, and laser confocal microscopy. Under phosphate limitation, zoospores germinated and subsequently formed 2-4 spores, regardless of the nutritional content of the medium. The removal of phosphate at any time during growth induced sporulation of vegetative cells. If phosphate was later added to the same cultures, growth was restored if the cells were not yet committed to sporulation. The cycles of addition and withdrawal of phosphate from growth medium resulted in cycles of germination-growth, germination-sporulation, or germination-growth-sporulation. These results show that phosphate limitation is sufficient to interrupt cell growth and to induce complete sporulation in B. emersonii. We concluded that the determination of growth or sporulation in this microorganism is linked to phosphate availability when other nutrients are not limiting. This result provides a new tool for the dissection of nutrient-energy and signal pathways in cell growth and differentiation.
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796
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797
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Abstract
Expression of human Bax, a cardinal regulator of mitochondrial membrane permeabilization, causes death in yeast. We screened a human cDNA library for suppressors of Bax-mediated yeast death and identified human 14-3-3β/α, a protein whose paralogs have numerous chaperone-like functions. Here, we show that, yeast cells expressing human 14-3-3β/α are able to complement deletion of the endogenous yeast 14-3-3 and confer resistance to a variety of different stresses including cadmium and cycloheximide. The expression of 14-3-3β/α also conferred resistance to death induced by the target of rapamycin inhibitor rapamycin and by starvation for the amino acid leucine, conditions that induce autophagy. Cell death in response to these autophagic stimuli was also observed in the macroautophagic-deficient atg1Δ and atg7Δ mutants. Furthermore, 14-3-3β/α retained its ability to protect against the autophagic stimuli in these autophagic-deficient mutants arguing against so called 'autophagic death'. In line, analysis of cell death markers including the accumulation of reactive oxygen species, membrane integrity and cell surface exposure of phosphatidylserine indicated that 14-3-3β/α serves as a specific inhibitor of apoptosis. Finally, we demonstrate functional conservation of these phenotypes using the yeast homolog of 14-3-3: Bmh1. In sum, cell death in response to multiple stresses can be counteracted by 14-3-3 proteins.
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798
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Clapp C, Portt L, Khoury C, Sheibani S, Eid R, Greenwood M, Vali H, Mandato CA, Greenwood MT. Untangling the Roles of Anti-Apoptosis in Regulating Programmed Cell Death using Humanized Yeast Cells. Front Oncol 2012; 2:59. [PMID: 22708116 PMCID: PMC3374133 DOI: 10.3389/fonc.2012.00059] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 05/24/2012] [Indexed: 11/13/2022] Open
Abstract
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-apoptosis, we screened a human heart cDNA expression library in yeast cells undergoing PCD due to the conditional expression of a mammalian pro-apoptotic Bax cDNA. Analysis of the multiple Bax suppressors identified revealed several previously known as well as a large number of clones representing potential novel anti-apoptotic sequences. The focus of this review is to report on recent achievements in the use of humanized yeast in genetic screens to identify novel stress-induced PCD suppressors, supporting the use of yeast as a unicellular model organism to elucidate anti-apoptotic and cell survival mechanisms.
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Affiliation(s)
- Caitlin Clapp
- Department of Chemistry and Chemical Engineering, Royal Military College Kingston, ON, Canada
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799
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Guo FJ, Liu Y, Zhou J, Luo S, Zhao W, Li X, Liu C. XBP1S protects cells from ER stress-induced apoptosis through Erk1/2 signaling pathway involving CHOP. Histochem Cell Biol 2012; 138:447-60. [PMID: 22669460 DOI: 10.1007/s00418-012-0967-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/02/2012] [Indexed: 01/14/2023]
Abstract
The mammalian unfolded protein response (UPR) protects the cell against the stress of misfolded proteins in the endoplasmic reticulum (ER), and the transcription factor X-box binding protein 1 spliced (XBP1S), a regulator of the UPR, is known to be important for ER stress (ERS)-mediated apoptosis and cell growth, but the molecular mechanism underlying these processes remains unexplored. Here, we report that knockdown of XBP1S by an siRNA silencing approach increased the expression of ERS-associated molecules. The overexpression of XBP1S stimulated, whereas its knockdown inhibited, cell proliferation in chondrocytes and chondrosarcoma cells; in addition, overexpression of XBP1S inhibited, while its repression enhanced, ERS-mediated apoptosis in chondrocytes and chondrosarcoma cells. Furthermore, XBP1S-mediated inhibition of apoptosis in response to ERS is through the Erk1/2 signaling pathway and down-regulation CHOP transcription factor. CHOP is one of the key downstream molecules known to be involved in ERS-mediated apoptosis. Collectively, these findings reveal a novel critical role of XBP1S in ERS-mediated apoptosis and the molecular mechanisms involved.
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Affiliation(s)
- Feng-Jin Guo
- Department of Cell Biology and Genetics, Chongqing Medical University, Chongqing 400016, China.
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800
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Li X, Zhu H, Huang H, Jiang R, Zhao W, Liu Y, Zhou J, Guo FJ. Study on the effect of IRE1a on cell growth and apoptosis via modulation PLK1 in ER stress response. Mol Cell Biochem 2012; 365:99-108. [PMID: 22314839 DOI: 10.1007/s11010-012-1248-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 01/14/2012] [Indexed: 11/27/2022]
Abstract
The mammalian unfolded protein response (UPR) protects the cell against the stress of misfolded proteins in the endoplasmic reticulum (ER). Failure to adapt to ER stress causes the UPR to trigger apoptosis. Inositol-requiring enzyme-1a (IRE1a), as one of three unfolded protein sensors in UPR signaling pathways, senses ER unfolded proteins through an ER lumenal domain that becomes oligomerized during ER stress. It is known to be important for ER stress-mediated apoptosis and cell growth, but the exact molecular mechanism underlying these processes remains unexplored. In this study, we report that knockdown of IRE1a by an siRNA silencing approach enhanced, whereas its overexpression inhibited, cell proliferation in Hepatoma cells. Besides, overexpression of IRE1a induced, while its repression inhibited, ER stress-mediated apoptosis in Hepatomas cells. Furthermore, we found that overexpressed IRE1a can down-regulate Polo-like kinase 1(PLK1) from mRNA and protein two levels. IRE1a-mediated induction of apoptosis and inhibition of proliferation in response to ER stress is through downregulation PLK1, an early trigger for G2/M transition known to be participated in regulating cell proliferation and cell apoptosis. Collectively, these findings reveal a novel critical role of IRE1a in ER stress-mediated apoptosis and the molecular mechanisms involved. IRE1a may be a useful molecular target for the development of novel predictive and therapeutic strategies in cancer.
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Affiliation(s)
- Xiangzhu Li
- Department of Cell Biology and Genetics, ChongQing Medical University, ChongQing 400016, China
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