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Nakada M, Kanda J, Uchiyama H, Matsumura K. Nanoscale intracellular ultrastructures affected by osmotic pressure using small-angle X-ray scattering. Biophys Chem 2024; 312:107287. [PMID: 38981174 DOI: 10.1016/j.bpc.2024.107287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Revised: 06/12/2024] [Accepted: 06/26/2024] [Indexed: 07/11/2024]
Abstract
Although intracellular ultrastructures have typically been studied using microscopic techniques, it is difficult to observe ultrastructures at the submicron scale of living cells due to spatial resolution (fluorescence microscopy) or high vacuum environment (electron microscopy). We investigate the nanometer scale intracellular ultrastructures of living CHO cells in various osmolality using small-angle X-ray scattering (SAXS), and especially the structures of ribosomes, DNA double helix, and plasma membranes in-cell environment are observed. Ribosomes expand and contract in response to osmotic pressure, and the inter-ribosomal correlation occurs under isotonic and hyperosmolality. The DNA double helix is not dependent on the osmotic pressure. Under high osmotic pressure, the plasma membrane folds into form a multilamellar structure with a periodic length of about 6 nm. We also study the ultrastructural changes caused by formaldehyde fixation, freezing and heating.
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Affiliation(s)
- Masaru Nakada
- Toray Research Center, Inc., 2-11 Sonoyama 3-chome, Otsu, Shiga 520-8567, Japan.
| | - Junko Kanda
- Toray Research Center, Inc., 2-11 Sonoyama 3-chome, Otsu, Shiga 520-8567, Japan
| | - Hironobu Uchiyama
- Toray Research Center, Inc., 2-11 Sonoyama 3-chome, Otsu, Shiga 520-8567, Japan
| | - Kazuaki Matsumura
- School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan
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2
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Williams TD, Rousseau A. Translation regulation in response to stress. FEBS J 2024. [PMID: 38308808 DOI: 10.1111/febs.17076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 12/07/2023] [Accepted: 01/22/2024] [Indexed: 02/05/2024]
Abstract
Cell stresses occur in a wide variety of settings: in disease, during industrial processes, and as part of normal day-to-day rhythms. Adaptation to these stresses requires cells to alter their proteome. Cells modify the proteins they synthesize to aid proteome adaptation. Changes in both mRNA transcription and translation contribute to altered protein synthesis. Here, we discuss the changes in translational mechanisms that occur following the onset of stress, and the impact these have on stress adaptation.
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Affiliation(s)
- Thomas D Williams
- MRC-PPU, School of Life Sciences, University of Dundee, UK
- Sir William Dunn School of Pathology, University of Oxford, UK
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3
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Singh SS, Mansuri MS, Naiyer S, Kaur D, Agrahari M, Srinivasan S, Jhingan GD, Bhattacharya A, Bhattacharya S. Multi-omics analysis to characterize molecular adaptation of Entamoeba histolytica during serum stress. Proteomics 2022; 22:e2200148. [PMID: 36066285 DOI: 10.1002/pmic.202200148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 08/07/2022] [Accepted: 08/19/2022] [Indexed: 12/29/2022]
Abstract
Entamoeba histolytica is responsible for dysentery and extraintestinal disease in humans. To establish successful infection, it must generate adaptive response against stress due to host defense mechanisms. We have developed a robust proteomics workflow by combining miniaturized sample preparation, low flow-rate chromatography, and ultra-high sensitivity mass spectrometry, achieving increased proteome coverage, and further integrated proteomics and RNA-seq data to decipher regulation at translational and transcriptional levels. Label-free quantitative proteomics led to identification of 2344 proteins, an improvement over the maximum number identified in E. histolytica proteomic studies. In serum-starved cells, 127 proteins were differentially abundant and were associated with functions including antioxidant activity, cytoskeleton, translation, catalysis, and transport. The virulence factor, Gal/GalNAc-inhibitable lectin subunits, was significantly altered. Integration of transcriptomic and proteomic data revealed that only 30% genes were coordinately regulated at both transcriptional and translational levels. Some highly expressed transcripts did not change in protein abundance. Conversely, genes with no transcriptional change showed enhanced protein abundance, indicating post-transcriptional regulation. This multi-omics approach enables more refined gene expression analysis to understand the adaptive response of E. histolytica during growth stress.
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Affiliation(s)
- Shashi Shekhar Singh
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India.,Center for RNA Science and Therapeutics, Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Mohammad Shahid Mansuri
- Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Sarah Naiyer
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India.,Department of Immunology and Microbiology, University of Illinois Chicago, Chicago, Illinois, USA
| | - Devinder Kaur
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India.,Central University of Punjab, Bathinda, Punjab, India
| | - Mridula Agrahari
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India.,Vproteomics, Valerian Chem Private Limited, New Delhi, India
| | | | | | - Alok Bhattacharya
- Ashoka University, Rajiv Gandhi Education City, Sonipat, Haryana, India
| | - Sudha Bhattacharya
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India.,Ashoka University, Rajiv Gandhi Education City, Sonipat, Haryana, India
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4
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Disruption of Chromatin Dynamics by Hypotonic Stress Suppresses HR and Shifts DSB Processing to Error-Prone SSA. Int J Mol Sci 2021; 22:ijms222010957. [PMID: 34681628 PMCID: PMC8535785 DOI: 10.3390/ijms222010957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/04/2021] [Accepted: 10/05/2021] [Indexed: 11/17/2022] Open
Abstract
The processing of DNA double-strand breaks (DSBs) depends on the dynamic characteristics of chromatin. To investigate how abrupt changes in chromatin compaction alter these dynamics and affect DSB processing and repair, we exposed irradiated cells to hypotonic stress (HypoS). Densitometric and chromosome-length analyses show that HypoS transiently decompacts chromatin without inducing histone modifications known from regulated local chromatin decondensation, or changes in Micrococcal Nuclease (MNase) sensitivity. HypoS leaves undisturbed initial stages of DNA-damage-response (DDR), such as radiation-induced ATM activation and H2AX-phosphorylation. However, detection of ATM-pS1981, γ-H2AX and 53BP1 foci is reduced in a protein, cell cycle phase and cell line dependent manner; likely secondary to chromatin decompaction that disrupts the focal organization of DDR proteins. While HypoS only exerts small effects on classical nonhomologous end-joining (c-NHEJ) and alternative end-joining (alt-EJ), it markedly suppresses homologous recombination (HR) without affecting DNA end-resection at DSBs, and clearly enhances single-strand annealing (SSA). These shifts in pathway engagement are accompanied by decreases in HR-dependent chromatid-break repair in the G2-phase, and by increases in alt-EJ and SSA-dependent chromosomal translocations. Consequently, HypoS sensitizes cells to ionizing radiation (IR)-induced killing. We conclude that HypoS-induced global chromatin decompaction compromises regulated chromatin dynamics and genomic stability by suppressing DSB-processing by HR, and allowing error-prone processing by alt-EJ and SSA.
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5
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Romanova N, Niemann T, Greiner JFW, Kaltschmidt B, Kaltschmidt C, Noll T. Hyperosmolality in CHO culture: Effects on cellular behavior and morphology. Biotechnol Bioeng 2021; 118:2348-2359. [PMID: 33751545 DOI: 10.1002/bit.27747] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/23/2021] [Accepted: 03/08/2021] [Indexed: 01/02/2023]
Abstract
Exposure of Chinese hamster ovary cells (CHO) to highly concentrated feed solution during fed-batch cultivation is known to result in an unphysiological osmolality increase (>300 mOsm/kg), affecting cell physiology and morphology. Extending previous observation on osmotic adaptation, the present study investigates for the first time potential effects of hyperosmolality on CHO cells on both population and single-cell level. We intentionally exposed CHO cells to hyperosmolality of up to 545 mOsm/kg during fed-batch cultivation. In concordance with existing research data, hyperosmolality-exposed CHO cells showed a nearly triplicated volume accompanied by ablation of proliferation. On the molecular level, we observed a strong hyperosmolality-dependent increase in mitochondrial activity in CHO cells compared to control. In contrast to mitochondrial activity, hyperosmolality-dependent proliferation arrest of CHO cells was not accompanied by DNA accumulation or caspase-3/7-mediated apoptosis. Notably, we demonstrate for the first time a formation of up to eight multiple, small nuclei in single hyperosmolality-stressed CHO cells. The here presented observations reveal previously unknown hyperosmolality-dependent morphological changes in CHO cells and support existing data on the osmotic response in mammalian cells.
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Affiliation(s)
- Nadiya Romanova
- Cell Culture Technology, Faculty of Technology, Bielefeld University, Bielefeld, Germany
| | - Tarek Niemann
- AG Molecular Neurobiology, Faculty of Biology, Bielefeld University, Bielefeld, Germany
- Department of Cell Biology, Faculty of Biology, University of Bielefeld, Universitaetsstrasse 25, Bielefeld, 33615, Germany
| | - Johannes F W Greiner
- Department of Cell Biology, Faculty of Biology, University of Bielefeld, Universitaetsstrasse 25, Bielefeld, 33615, Germany
| | - Barbara Kaltschmidt
- AG Molecular Neurobiology, Faculty of Biology, Bielefeld University, Bielefeld, Germany
- Department of Cell Biology, Faculty of Biology, University of Bielefeld, Universitaetsstrasse 25, Bielefeld, 33615, Germany
| | - Christian Kaltschmidt
- Department of Cell Biology, Faculty of Biology, University of Bielefeld, Universitaetsstrasse 25, Bielefeld, 33615, Germany
| | - Thomas Noll
- Cell Culture Technology, Faculty of Technology, Bielefeld University, Bielefeld, Germany
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6
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Maitra D, Carter EL, Richardson R, Rittié L, Basrur V, Zhang H, Nesvizhskii AI, Osawa Y, Wolf MW, Ragsdale SW, Lehnert N, Herrmann H, Omary MB. Oxygen and Conformation Dependent Protein Oxidation and Aggregation by Porphyrins in Hepatocytes and Light-Exposed Cells. Cell Mol Gastroenterol Hepatol 2019; 8:659-682.e1. [PMID: 31173894 PMCID: PMC6889786 DOI: 10.1016/j.jcmgh.2019.05.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/28/2019] [Accepted: 05/28/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Porphyrias are caused by porphyrin accumulation resulting from defects in the heme biosynthetic pathway that typically lead to photosensitivity and possible end-stage liver disease with an increased risk of hepatocellular carcinoma. Our aims were to study the mechanism of porphyrin-induced cell damage and protein aggregation, including liver injury, where light exposure is absent. METHODS Porphyria was induced in vivo in mice using 3,5-diethoxycarbonyl-1,4-dihydrocollidine or in vitro by exposing human liver Huh7 cells and keratinocytes, or their lysates, to protoporphyrin-IX, other porphyrins, or to δ-aminolevulinic acid plus deferoxamine. The livers, cultured cells, or porphyrin exposed purified proteins were analyzed for protein aggregation and oxidation using immunoblotting, mass spectrometry, and electron paramagnetic resonance spectroscopy. Consequences on cell-cycle progression were assessed. RESULTS Porphyrin-mediated protein aggregation required porphyrin-photosensitized singlet oxygen and porphyrin carboxylate side-chain deprotonation, and occurred with site-selective native protein methionine oxidation. Noncovalent interaction of protoporphyrin-IX with oxidized proteins led to protein aggregation that was reversed by incubation with acidified n-butanol or high-salt buffer. Phototoxicity and the ensuing proteotoxicity, mimicking porphyria photosensitivity conditions, were validated in cultured keratinocytes. Protoporphyrin-IX inhibited proteasome function by aggregating several proteasomal subunits, and caused cell growth arrest and aggregation of key cell proliferation proteins. Light-independent synergy of protein aggregation was observed when porphyrin was applied together with glucose oxidase as a secondary peroxide source. CONCLUSIONS Photo-excitable porphyrins with deprotonated carboxylates mediate protein aggregation. Porphyrin-mediated proteotoxicity in the absence of light, as in the liver, requires porphyrin accumulation coupled with a second tissue oxidative injury. These findings provide a potential mechanism for internal organ damage and photosensitivity in porphyrias.
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Affiliation(s)
- Dhiman Maitra
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan,Correspondence Address correspondence to: Dhiman Maitra, PhD, Department of Molecular and Integrative Physiology, University of Michigan Medical School, 7720 Medical Science Building II, 1137 Catherine Street, Ann Arbor, Michigan 48109-5622. fax: (734) 936–8813.
| | - Eric L. Carter
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan
| | - Rani Richardson
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan
| | - Laure Rittié
- Department of Dermatology, University of Michigan, Ann Arbor, Michigan
| | - Venkatesha Basrur
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Haoming Zhang
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan
| | | | - Yoichi Osawa
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan
| | - Matthew W. Wolf
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan
| | - Stephen W. Ragsdale
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan
| | - Nicolai Lehnert
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan,Department of Biophysics, University of Michigan, Ann Arbor, Michigan
| | - Harald Herrmann
- Institute of Neuropathology, University Hospital Erlangen, Erlangen, Germany,Division of Molecular Genetics, German Cancer Research Center, Heidelberg, Germany
| | - M. Bishr Omary
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan,Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan,Cell Biology, Faculty of Science and Technology, Åbo Akademi University, Turku, Finland
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7
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Akulich KA, Sinitcyn PG, Makeeva DS, Andreev DE, Terenin IM, Anisimova AS, Shatsky IN, Dmitriev SE. A novel uORF-based regulatory mechanism controls translation of the human MDM2 and eIF2D mRNAs during stress. Biochimie 2018; 157:92-101. [PMID: 30419262 DOI: 10.1016/j.biochi.2018.11.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 11/06/2018] [Indexed: 01/02/2023]
Abstract
Short upstream open reading frames (uORFs) are the most prevalent cis-acting regulatory elements in the mammalian transcriptome which can orchestrate mRNA translation. Apart from being "passive roadblocks" that decrease expression of the main coding regions, particular uORFs can serve as specific sensors for changing conditions, thus regulating translation in response to cell stress. Here we report a novel uORF-based regulatory mechanism that is employed under conditions of hyperosmotic stress by at least two human mRNAs, coding for translation reinitiation/recycling factor eIF2D and E3 ubiquitin ligase MDM2. This novel mode of translational control selectively downregulates their expression and requires as few as one uORF. Using a set of reporter mRNAs and fleeting mRNA transfection (FLERT) technique, we provide evidence that the phenomenon does not rely on delayed reinitiation, altered AUG recognition, ribosome stalling, mRNA destabilization or other known mechanisms. Instead, it is based on events taking place at uORF stop codon or immediately downstream. Functional aspects and implications of the novel regulatory mechanism to cell physiology are discussed.
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Affiliation(s)
- Kseniya A Akulich
- School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119234, Russia; Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Pavel G Sinitcyn
- School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Desislava S Makeeva
- School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119234, Russia; Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Dmitry E Andreev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Ilya M Terenin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia; Sechenov First Moscow State Medical University, Institute of Molecular Medicine, 119991, Moscow, Russia
| | - Aleksandra S Anisimova
- School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119234, Russia; Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Ivan N Shatsky
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Sergey E Dmitriev
- School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119234, Russia; Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119234, Russia; Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, 119991, Russia; Department of Biochemistry, Biological Faculty, Lomonosov Moscow State University, Moscow, 119991, Russia.
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8
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Zhao Z, Dammert MA, Grummt I, Bierhoff H. lncRNA-Induced Nucleosome Repositioning Reinforces Transcriptional Repression of rRNA Genes upon Hypotonic Stress. Cell Rep 2016; 14:1876-82. [PMID: 26904956 DOI: 10.1016/j.celrep.2016.01.073] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 12/09/2015] [Accepted: 01/23/2016] [Indexed: 11/29/2022] Open
Abstract
The activity of rRNA genes (rDNA) is regulated by pathways that target the transcription machinery or alter the epigenetic state of rDNA. Previous work has established that downregulation of rRNA synthesis in quiescent cells is accompanied by upregulation of PAPAS, a long noncoding RNA (lncRNA) that recruits the histone methyltransferase Suv4-20h2 to rDNA, thus triggering trimethylation of H4K20 (H4K20me3) and chromatin compaction. Here, we show that upregulation of PAPAS in response to hypoosmotic stress does not increase H4K20me3 because of Nedd4-dependent ubiquitinylation and proteasomal degradation of Suv4-20h2. Loss of Suv4-20h2 enables PAPAS to interact with CHD4, a subunit of the chromatin remodeling complex NuRD, which shifts the promoter-bound nucleosome into the transcriptional "off" position. Thus, PAPAS exerts a "stress-tailored" dual function in rDNA silencing, facilitating either Suv4-20h2-dependent chromatin compaction or NuRD-dependent changes in nucleosome positioning.
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Affiliation(s)
- Zhongliang Zhao
- Division of Molecular Biology of the Cell II, German Cancer Research Center, DKFZ-ZMBH Alliance, Im Neuenheimer Feld 581, 69120 Heidelberg, Germany
| | - Marcel Andre Dammert
- Division of Molecular Biology of the Cell II, German Cancer Research Center, DKFZ-ZMBH Alliance, Im Neuenheimer Feld 581, 69120 Heidelberg, Germany
| | - Ingrid Grummt
- Division of Molecular Biology of the Cell II, German Cancer Research Center, DKFZ-ZMBH Alliance, Im Neuenheimer Feld 581, 69120 Heidelberg, Germany
| | - Holger Bierhoff
- Division of Molecular Biology of the Cell II, German Cancer Research Center, DKFZ-ZMBH Alliance, Im Neuenheimer Feld 581, 69120 Heidelberg, Germany.
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9
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Syed HC, Dubreuil JD. Escherichia coli STb toxin induces apoptosis in intestinal epithelial cell lines. Microb Pathog 2012; 53:147-53. [DOI: 10.1016/j.micpath.2012.06.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 06/12/2012] [Accepted: 06/26/2012] [Indexed: 11/30/2022]
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10
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Growing insights into the safety of bacteriocins: the case of enterocin S37. Res Microbiol 2010; 162:159-63. [PMID: 21035542 DOI: 10.1016/j.resmic.2010.09.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2010] [Accepted: 09/14/2010] [Indexed: 11/20/2022]
Abstract
Very few studies have been reported on the cytotoxicity and impact of bacteriocins, and especially enterocins, upon eukaryotic cells. In order to gain more information on the safety of bacteriocins, we focused this study on enterocin S37, a bacteriocin produced by Enterococcus faecalis S37. We observed dose-dependent cytotoxicity toward undifferentiated Caco-2/TC7 cells. Moreover, no significant effect on differentiated monolayer Caco-2/TC7 and no apoptotic features were observed when cells were treated with 10 μg/ml of enterocin S37. The results obtained indicate possible safe use of enterocin S37 in the gastrointestinal tract of animals to prevent pathogen invasion and/or infection.
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11
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Zhou YM, Guo W, Zhou H, Zhang JH, Liu ZP, Yu MX. MG132 induced apoptosis pathway in HL-60 cells and impact of allogeneic mixed lymphocyte reaction. Chin J Cancer Res 2009. [DOI: 10.1007/s11670-009-0333-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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12
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Balatoni CE, Dawson DW, Suh J, Sherman MH, Sanders G, Hong JS, Frank MJ, Malone CS, Said JW, Teitell MA. Epigenetic silencing of Stk39 in B-cell lymphoma inhibits apoptosis from genotoxic stress. THE AMERICAN JOURNAL OF PATHOLOGY 2009; 175:1653-61. [PMID: 19717643 DOI: 10.2353/ajpath.2009.090091] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
B-cell lymphomas, the most frequent human immune system malignancies, often contain dysregulated TCL1 oncogene expression. TCL1 transgenic (TCL1-tg) mice develop a spectrum of B-cell malignancies, supporting an oncogenic role for TCL1 in B cells. Our prior global survey of DNA methylation patterns in TCL1-tg B-cell lymphomas identified many lymphoma-specific candidate hypermethylated genes, including Stk39. The Stk39 encoded protein, sterile 20-like-related proline-alanine-rich kinase (SPAK), regulates cell stress responses, and microarray studies identified reduced SPAK expression in metastatic prostate and treatment-resistant breast cancers, suggesting that its loss may have a role in cancer progression. Here we identified DNA hypermethylation and SPAK silencing in TCL1-tg B-cell lymphomas and SPAK silencing without DNA methylation in multiple subtypes of human B-cell lymphomas. SPAK knockdown by shRNA protected B cells from caspase-dependent apoptosis induced by DNA double-strand breaks but not apoptosis in response to osmotic or oxidative cell stressors. Caspase 3 activation by cleavage was impaired with SPAK repression in DNA damaged B cells. Interestingly, c-Jun NH(2)-terminal kinase is potentially activated by SPAK and pharmacological inhibition of c-Jun NH(2)-terminal kinase in SPAK-expressing B cells recapitulated the cell-protective phenotype of SPAK knockdown. Taken together, these data indicate that SPAK loss in B-cell lymphomas promotes increased cell survival with DNA damage and provides a potential mechanism for increased resistance to genotoxic stress in cancer.
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Affiliation(s)
- Cynthia E Balatoni
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
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13
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Zhou YM, Yu MX, Long H, Huang SA. Anti-tumor action and clinical application of proteasome inhibitor. Chin J Cancer Res 2008. [DOI: 10.1007/s11670-008-0077-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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14
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Voutsadakis IA. Pathogenesis of colorectal carcinoma and therapeutic implications: the roles of the ubiquitin-proteasome system and Cox-2. J Cell Mol Med 2007; 11:252-85. [PMID: 17488476 PMCID: PMC3822826 DOI: 10.1111/j.1582-4934.2007.00032.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Pathways of the molecular pathogenesis of colorectal carcinoma have been extensively studied and molecular lesions during the development of the disease have been revealed. High up in the list of colorectal cancer lesions are APC (adenomatous polyposis coli), K-ras, Smad4 (or DPC4-deleted in pancreatic cancer 4) and p53 genes. All these molecules are part of important pathways for the regulation of cell proliferation and apoptosis and as a result perturbation of these processes lead to carcinogenesis. The ubiquitin-proteasome system (UPS) is comprised of a multi-unit cellular protease system that regulates several dozens of cell proteins after their ligation with the protein ubiquitin. Given that among these proteins are regulators of the cell cycle, apoptosis, angiogenesis, adhesion and cell signalling, this system plays a significant role in cell fate and carcinogenesis. UPS inhibition has been found to be a pre-requisite for apoptosis and is already clinically exploited with the proteasome inhibitor bortezomib in multiple myeloma. Cyclooxygenase-2 (Cox-2) is the inducible form of the enzyme that metabolizes the lipid arachidonic acid to prostaglandin H2, the first step of prostaglandins production. This enzyme is up-regulated in colorectal cancer and in several other cancers. Inhibition of Cox-2 by aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) has been found to inhibit proliferation of colorectal cancer cells and in epidemiologic studies has been shown to reduce colon polyp formation in genetically predisposed populations and in the general population. NSAIDs have also Cox-independent anti-proliferative effects. Targeted therapies, the result of increasingly understanding carcinogenesis in the molecular level, have entered the field of anti-neoplastic treatment and are used by themselves and in combination with chemotherapy drugs. Combinations of targeted drugs have started also to be investigated. This article reviews the molecular pathogenesis of colorectal cancer, the roles of UPS and Cox-2 in it and puts forward a rational for their combined inhibition in colorectal cancer treatment.
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Affiliation(s)
- Ioannis A Voutsadakis
- Division of Medical Oncology, University Hospital of Larissa, Larissa 41110, Greece.
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15
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Criollo A, Galluzzi L, Chiara Maiuri M, Tasdemir E, Lavandero S, Kroemer G. Mitochondrial control of cell death induced by hyperosmotic stress. Apoptosis 2007; 12:3-18. [PMID: 17080328 PMCID: PMC2799004 DOI: 10.1007/s10495-006-0328-x] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
HeLa and HCT116 cells respond differentially to sorbitol, an osmolyte able to induce hypertonic stress. In these models, sorbitol promoted the phenotypic manifestations of early apoptosis followed by complete loss of viability in a time-, dose-, and cell type-specific fashion, by eliciting distinct yet partially overlapping molecular pathways. In HCT116 but not in HeLa cells, sorbitol caused the mitochondrial release of the caspase-independent death effector AIF, whereas in both cell lines cytochrome c was retained in mitochondria. Despite cytochrome c retention, HeLa cells exhibited the progressive activation of caspase-3, presumably due to the prior activation of caspase-8. Accordingly, caspase inhibition prevented sorbitol-induced killing in HeLa, but only partially in HCT116 cells. Both the knock-out of Bax in HCT116 cells and the knock-down of Bax in A549 cells by RNA interference reduced the AIF release and/or the mitochondrial alterations. While the knock-down of Bcl-2/Bcl-X(L) sensitized to sorbitol-induced killing, overexpression of a Bcl-2 variant that specifically localizes to mitochondria (but not of the wild-type nor of a endoplasmic reticulum-targeted form) strongly inhibited sorbitol effects. Thus, hyperosmotic stress kills cells by triggering different molecular pathways, which converge at mitochondria where pro- and anti-apoptotic members of the Bcl-2 family exert their control.
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Affiliation(s)
- Alfredo Criollo
- />Institut Gustave Roussy - 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />INSERM, Unit “Apoptosis, Cancer and Immunity”- 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />Faculté de Médecine, Université Paris-Sud XI - 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />Department of Biochemistry and Molecular Biology, Faculty of Chemical and Pharmaceutical Sciences, FONDAP Center for Molecular Studies of the Cell, University of Chile, Olivos 1007, Santiago, 8380492 Chile
| | - Lorenzo Galluzzi
- />Institut Gustave Roussy - 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />INSERM, Unit “Apoptosis, Cancer and Immunity”- 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />Faculté de Médecine, Université Paris-Sud XI - 39 rue Camille Desmoulins, F-94805 Villejuif, France
| | - M. Chiara Maiuri
- />Institut Gustave Roussy - 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />INSERM, Unit “Apoptosis, Cancer and Immunity”- 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />Faculté de Médecine, Université Paris-Sud XI - 39 rue Camille Desmoulins, F-94805 Villejuif, France
| | - Ezgi Tasdemir
- />Institut Gustave Roussy - 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />INSERM, Unit “Apoptosis, Cancer and Immunity”- 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />Faculté de Médecine, Université Paris-Sud XI - 39 rue Camille Desmoulins, F-94805 Villejuif, France
| | - Sergio Lavandero
- />Department of Biochemistry and Molecular Biology, Faculty of Chemical and Pharmaceutical Sciences, FONDAP Center for Molecular Studies of the Cell, University of Chile, Olivos 1007, Santiago, 8380492 Chile
| | - Guido Kroemer
- />Institut Gustave Roussy - 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />INSERM, Unit “Apoptosis, Cancer and Immunity”- 39 rue Camille Desmoulins, F-94805 Villejuif, France
- />Faculté de Médecine, Université Paris-Sud XI - 39 rue Camille Desmoulins, F-94805 Villejuif, France
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Lucas BS, Gopalsamuthiram V, Burke SD. Total Synthesis of Phorboxazole B. Angew Chem Int Ed Engl 2007; 46:769-72. [PMID: 17163573 DOI: 10.1002/anie.200603656] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Brian S Lucas
- Department of Chemistry, The University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA
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Låhne HU, Kloster MM, Lefdal S, Blomhoff HK, Naderi S. Degradation of cyclin D3 independent of Thr-283 phosphorylation. Oncogene 2006; 25:2468-76. [PMID: 16331257 DOI: 10.1038/sj.onc.1209278] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Cyclin D3 has been shown to play a major role in the regulation of cell cycle progression in lymphocytes. It is therefore important to understand the mechanisms involved in the regulation of this protein. We have previously shown that both basal and cAMP-induced degradation of cyclin D3 in Reh cells is dependent on Thr-283 phosphorylation by glycogen synthase kinase-3beta (GSK-3beta). We now provide evidence of an alternative mechanism being involved in the regulation of cyclin D3 degradation. Treatment of lymphoid cells with okadaic acid (OA), an inhibitor of protein phosphatases 1 and 2A (PP1 and PP2A), induces rapid phosphorylation and proteasomal degradation of cyclin D3. This degradation is not inhibited by the GSK-3beta inhibitors lithium or Kenpaullone, or by substitution of Thr-283 with Ala on cyclin D3, indicating that cyclin D3 can be degraded independently of Thr-283 phosphorylation and GSK-3beta activity. Interestingly, in vitro experiments revealed that PP1, but not PP2A, was able to dephosphorylate cyclin D3 efficiently, and PP1 was found to associate with His-tagged cyclin D3. These results support the hypothesis that PP1 constitutively keeps cyclin D3 in a stable, dephosphorylated state, and that treatment of cells with OA leads to phosphorylation and degradation of cyclin D3 through inhibition of PP1.
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Affiliation(s)
- H U Låhne
- Department of Biochemistry, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1112 Blindern, Oslo, Norway
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Bringhurst RM, Schaffer PA. Cellular stress rather than stage of the cell cycle enhances the replication and plating efficiencies of herpes simplex virus type 1 ICP0- viruses. J Virol 2006; 80:4528-37. [PMID: 16611913 PMCID: PMC1472003 DOI: 10.1128/jvi.80.9.4528-4537.2006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This lab reported previously that the plating efficiency of a herpes simplex virus type 1 ICP0-null mutant was enhanced upon release from an isoleucine block which synchronizes cells to G1 phase (W. Cai and P. A. Schaffer, J. Virol. 65:4078-4090, 1991). Peak plating efficiency occurred as cells cycled out of G1 and into S phase, suggesting that the enhanced plating efficiency was due to cellular activities present in late G1/early S phase. We have found, however, that the enhanced plating efficiency did not occur when cells were synchronized by alternative methods. We now report that the plating efficiency of ICP0- viruses is not enhanced at a particular stage of the cell cycle but rather is enhanced by specific cellular stresses. Both the plating and replication efficiencies of ICP0- viruses were enhanced as much as 25-fold to levels similar to that of wild-type virus when monolayers were heat shocked prior to infection. In addition to heat shock, UV-C irradiation but not cold shock of monolayers prior to infection resulted in enhanced plating efficiency. We further report that the effect of cellular stress is transient and that cell density rather than age of the monolayers is the primary determinant of ICP0- virus plating efficiency. As both cell stress and ICP0 are required for efficient reactivation from latency, the identification of cellular activities that complement ICP0- viruses may lead to the identification of cellular activities that are important for reactivation from neuronal latency.
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Affiliation(s)
- Ryan M Bringhurst
- Department of Medicine, Harvard Medical School at Beth Israel Deaconess Medical Center, 330 Brookline Ave., RN 123, Boston, Massachusetts 02215, USA
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Tao GZ, Toivola DM, Zhou Q, Strnad P, Xu B, Michie SA, Omary MB. Protein phosphatase-2A associates with and dephosphorylates keratin 8 after hyposmotic stress in a site- and cell-specific manner. J Cell Sci 2006; 119:1425-32. [PMID: 16554440 DOI: 10.1242/jcs.02861] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Keratins 8 and 18 (K8 and K18) are regulated by site-specific phosphorylation in response to multiple stresses. We examined the effect and regulation of hyposmotic stress on keratin phosphorylation. K8 phospho-Ser431 (Ser431-P) becomes dephosphorylated in HT29 cells, but hyperphosphorylated on other K8 but not K18 sites in HRT18 and Caco2 cells and in normal human colonic ex vivo cultures. Hyposmosis-induced dephosphorylation involves K8 but not K18, K19 or K20, occurs preferentially in mitotically active cells, and peaks by 6-8 hours then returns to baseline by 12-16 hours. By contrast, hyperosmosis causes K8 Ser431 hyperphosphorylation in all tested cell lines. Hyposmosis-induced dephosphorylation of K8 Ser431-P is inhibited by okadaic acid but not by tautomycin or cyclosporine. The PP2A catalytic subunit co-immunoprecipitated with K8 and K18 after hyposmotic stress in HT29 cells, but not in HRT18 or Caco2 cells where K8 Ser431 becomes hyperphosphorylated. K8 Ser431-P dephosphorylation after hyposmosis was independent of PP2A levels but correlated with increased PP2A activity towards K8 Ser431-P. Therefore, hyposmotic stress alters K8 phosphorylation in a cell-dependent manner, and renders K8 Ser431-P a physiologic substrate for PP2A in HT29 cells as a result of PP2A activation and the physical association with K8 and K18. The divergent hyposmosis versus hyperosmosis K8 Ser431 phosphorylation changes in HT29 cells suggest that there are unique signaling responses to osmotic stress.
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Affiliation(s)
- Guo-Zhong Tao
- Department of Medicine, Palo Alto VA Medical Center, 3801 Miranda Avenue, Mail Code 154J, Palo Alto, CA 94304, USA.
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Forsyth CJ, Ying L, Chen J, La Clair JJ. Phorboxazole Analogues Induce Association of cdk4 with Extranuclear Cytokeratin Intermediate Filaments. J Am Chem Soc 2006; 128:3858-9. [PMID: 16551063 DOI: 10.1021/ja057087e] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The cellular localization profile and molecular association of the phorboxazoles were examined with a streamlined target elucidation system using synthetic fluorescent probes. Cellular image analyses identified the binding of phorboxazole analogues to cytosolic components. Proteomic analysis directed at fluorescently labeled cytosolic fractions indicated that the primary targets observed microscopically were cytokeratins, as verified by determination of low nanomolar binding to cloned and expressed proteins. Phorboxazole probes localized the essential cell cycle promoter cdk4 upon cytokeratin networks.
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Affiliation(s)
- Craig J Forsyth
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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Rieber M, Rieber MS. Signalling responses linked to betulinic acid-induced apoptosis are antagonized by MEK inhibitor U0126 in adherent or 3D spheroid melanoma irrespective of p53 status. Int J Cancer 2006; 118:1135-43. [PMID: 16152620 DOI: 10.1002/ijc.21478] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
MEK1/2 inhibitors like U0126 can potentiate or antagonize the antitumor activity of cytotoxic agents such as cisplatin, paclitaxel or vinblastine, depending on the drug or the target cells. We now investigated whether U0126, differentially regulates melanoma signaling in response to UV radiation or betulinic acid, a drug lethal against melanoma. This report shows that U0126 inhibits early response (ERK) kinase activation and cyclin A expression in wt p53 C8161 melanoma exposed to either UV radiation or betulinic acid. However, U0126 does not protect from UV damage, but counteracts betulinic acid-mediated apoptosis in the same cells. Protection from the latter drug by joint treatment with U0126 was also evident in wt p53 MelJuso melanoma and mutant p53 WM164 melanoma. The latter cells were the most responsive to betulinic acid, showing a selective decline in the cdk4 protein, without a comparable change in other key cell cycle proteins like cdc2, cdk2, cdk7 or cyclin A, prior to apoptosis-associated PARP fragmentation. Laser scanning cytometry also showed that betulinic acid induced a significant increase in chromatin condensation in WM164 melanoma irrespective of whether they were in adherent form or as multicellular spheroids. All these betulinic acid-induced changes were counteracted by U0126. Our data show for the first time that (a) cdk4 protein is an early target of betulinic acid-induced apoptosis and (b) unrestricted ERK signaling favours betulinic acid-induced apoptosis, but this is counteracted by U0126, partly through counteracting chromatin condensation and restoring Akt activation decreased by betulinic acid treatment.
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Affiliation(s)
- Manuel Rieber
- IVIC, Tumor Cell Biology Laboratory, Apartado 21827, Caracas 1020 A, Venezuela.
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Casanovas O, Jaumot M, Paules AB, Agell N, Bachs O. P38SAPK2 phosphorylates cyclin D3 at Thr-283 and targets it for proteasomal degradation. Oncogene 2004; 23:7537-44. [PMID: 15326477 DOI: 10.1038/sj.onc.1208040] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cyclin D3 plays a critical role in maturation of precursor T cells and their levels are tightly regulated during this process. Alteration of cyclin D3 levels has been proposed to be important in the development of different human cancers, including malignancies of the lymphoid system. Thus, we have analysed the mechanisms involved in the regulation of cyclin D3 levels. Our results indicate that cyclin D3 is degraded via proteasome and that Thr-283 is essential for its degradation. Wild-type cyclin D3 but not the Thr-283A mutant accumulated ubiquitylated forms after treatment with proteasome inhibitors. We also observed that different type of stresses promote the Thr-283-dependent in vivo degradation of cyclin D3. The analysis of the kinases involved in Thr-283 phosphorylation indicates that all the members of the p38SAPK family of serine-threonine kinases are able to phosphorylate cyclin D3 at this specific site. Moreover, we found that the overexpression of p38alphaSAPK2 induce the decrease of cyclin D3 in vivo. These results indicate that p38SAPK might be involved in the regulation of cyclin D3 levels and suggest that this mechanism is involved in the maturation of precursor T-cells. Alterations of this mechanism might be important for oncogenesis.
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Affiliation(s)
- Oriol Casanovas
- Departament de Biologia Cel lular i Anatomia Patològica, Facultat de Medicina, Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Casanova 143, 08036, Spain
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Marches R, Uhr JW. Enhancement of the p27Kip1-mediated antiproliferative effect of trastuzumab (Herceptin) on HER2-overexpressing tumor cells. Int J Cancer 2004; 112:492-501. [PMID: 15382077 DOI: 10.1002/ijc.20378] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The oncogenic activity of the overexpressed HER2 tyrosine kinase receptor requires its localization in the plasma membrane. The antitumor effect of anti-HER2 antibodies (Abs) is mainly dependent on receptor downregulation and comprises p27Kip1-mediated G1 cell cycle arrest. However, one major limitation of anti-HER2 therapy is the reversibility of tumor growth inhibition after discontinuation of treatment caused by the mitogenic signaling associated with cell surface receptor re-expression. We found that the level of p27Kip1 upregulation, inhibition of Cdk2 activity and magnitude of G1 arrest induced by the humanized Ab trastuzumab (Herceptin, HCT) on BT474 and SKBr3 HER2-overexpressing breast cancer cells correlates with the level of cell surface receptor. Thus, continuous exposure of cells to HCT for 72 hr results in downregulation of the cell surface receptor and a concurrent increase in the level of p27Kip1 protein. Discontinuation of Ab exposure after the first 8 hr results in failure to upregulate p27Kip1 and arrest of cell cycle progression. We show that the lysosomotropic amine chloroquine (CQ) augments receptor internalization in HER2-overexpressing cells either pretreated or continuously treated with HCT and leads to an increased and sustained inhibitory effect. The enhanced CQ-dependent loss of functional HER2 from the cell surface resulted in sustained inactivation of the serine/threonine kinase Akt, upregulation of p27Kip1 protein and inhibition of cyclin E/Cdk2 activity. Potentiation of the inhibitory effect of HCT by CQ was directly related to loss of HER2 from the plasma membrane since prevention of Ab-mediated receptor endocytosis by engagement of the receptor with immobilized HCT abrogated the effect of CQ.
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Affiliation(s)
- Radu Marches
- Cancer Immunobiology Center and Department of Microbiology, University of Texas Southwestern Medical School, Dallas, TX, USA.
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