101
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Sica RE. Is amyotrophic lateral sclerosis a primary astrocytic disease? Med Hypotheses 2012; 79:819-22. [PMID: 23026704 DOI: 10.1016/j.mehy.2012.08.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 08/15/2012] [Accepted: 08/23/2012] [Indexed: 12/12/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is thought to be due to primary involvement of motor neurons. Pathogenic mechanisms underlying its appearance are relatively well known and include inflammation, excitotoxicity, oxidative stress, endoplasmic reticulum stress, protein damage, genetic abnormalities and type of neuronal death. Although these processes have been investigated in detail in the past two decades none of them appear to be the cause of the illness. In addition several possible environmental agents have been investigated but the results, in every case, were conflicting and therefore inconclusive. However, since the motor neurons display the features of apoptosis in this illness, the possibility remains that the motor neurons die because of a hostile environment, one that is unable to sustain their health, rather than being directly targeted themselves. The above considerations lead to an examination of astrocytes, for these cells play a key role in controlling the environment of neurons. It is known that astrocytes are exquisitely plastic, adapting their metabolism and behaviour to the needs of the neurons they contact. Each population of astrocytes is therefore unique and, were one to be adversely affected at the start of a disease process, the consequences would extend to the neurons that it normally chaperoned. The disturbed relationship might involve inappropriate production and secretion of astrocytic neurotransmitters, defective transport of glutamate and impaired trophic and metabolic support of the motor neurons. In order to explain the spread of weakness and pyramidal signs in ALS patients, which is very often from one group of muscles to a neighbouring one, it is postulated that, within the spinal cord, the brainstem and the motor cortex, the disease-causing process is also spreading-in this case, from one group of astrocytes to its neighbours. A misfolded protein, possibly a prion-like protein, would be a candidate for this type of transmission.
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Affiliation(s)
- Roberto E Sica
- Department of Neurology, Buenos Aires University, Argentina.
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102
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Abstract
With advancing age, the brain becomes increasingly susceptible to neurodegenerative diseases, most of which are characterized by the misfolding and errant aggregation of certain proteins. The induction of aggregation involves a crystallization-like seeding mechanism by which a specific protein is structurally corrupted by its misfolded conformer. The latest research indicates that, once formed, proteopathic seeds can spread from one locale to another via cellular uptake, transport, and release. Impeding this process could represent a unified therapeutic strategy for slowing the progression of a wide range of currently intractable disorders.
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Affiliation(s)
- Lary C. Walker
- From the Yerkes National Primate Research Center and Department of Neurology, Emory University, Atlanta, Georgia 30329 and
| | - Harry LeVine
- the Center on Aging, Center for Structural Biology, and Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky 40536
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103
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Phani S, Re DB, Przedborski S. The Role of the Innate Immune System in ALS. Front Pharmacol 2012; 3:150. [PMID: 22912616 PMCID: PMC3418523 DOI: 10.3389/fphar.2012.00150] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 07/13/2012] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal, adult-onset neurodegenerative disease that is characterized by the death of upper and lower motor neurons. Recent studies have made it clear that although motor neurons are the primary targets of the degenerative process, other cell types play key roles in the death of motor neurons. Most notably, cells of the immune system, including astrocytes and microglia have come under increasing scrutiny, after multiple lines of evidence have shown these cells to be deleterious to motor neurons. Both in vitro and in vivo experiments have shown that astrocytes and microglia containing mutated SOD1 are harmful to motor neurons. Several studies on ALS and other neurodegenerative diseases have revealed that reactive astrocytes and microglia are capable of releasing pro-inflammatory factors such as cytokines and chemokines, which are harmful to neighboring neurons. In addition, it is believed that diseased astrocytes can specifically kill motor neurons through the release of toxic factors. Furthermore, in an animal model of the disease, it has been shown that the reduction of SOD1 in microglia may be able to slow the progression of ALS symptoms. Although the exact pathways of motor neuron death in ALS have yet to be elucidated, studies have suggested that they die through aBax-dependent signaling pathway. Mounting evidence suggests that neuroinflammation plays an important role in the degeneration of motor neurons. Based on these findings, anti-inflammatory compounds are currently being tested for their potential to reduce disease severity; however, these studies are only in the preliminary stages. While we understand that astrocytes and microglia play a role in the death of motor neurons in ALS, much work needs to be done to fully understand ALS pathology and the role the immune system plays in disease onset and progression.
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Affiliation(s)
- Sudarshan Phani
- Department of Pathology and Cell Biology, Columbia University New York, NY, USA
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104
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Ishiura H, Sako W, Yoshida M, Kawarai T, Tanabe O, Goto J, Takahashi Y, Date H, Mitsui J, Ahsan B, Ichikawa Y, Iwata A, Yoshino H, Izumi Y, Fujita K, Maeda K, Goto S, Koizumi H, Morigaki R, Ikemura M, Yamauchi N, Murayama S, Nicholson GA, Ito H, Sobue G, Nakagawa M, Kaji R, Tsuji S. The TRK-fused gene is mutated in hereditary motor and sensory neuropathy with proximal dominant involvement. Am J Hum Genet 2012; 91:320-9. [PMID: 22883144 DOI: 10.1016/j.ajhg.2012.07.014] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 05/27/2012] [Accepted: 07/02/2012] [Indexed: 11/16/2022] Open
Abstract
Hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P) is an autosomal-dominant neurodegenerative disorder characterized by widespread fasciculations, proximal-predominant muscle weakness, and atrophy followed by distal sensory involvement. To date, large families affected by HMSN-P have been reported from two different regions in Japan. Linkage and haplotype analyses of two previously reported families and two new families with the use of high-density SNP arrays further defined the minimum candidate region of 3.3 Mb in chromosomal region 3q12. Exome sequencing showed an identical c.854C>T (p.Pro285Leu) mutation in the TRK-fused gene (TFG) in the four families. Detailed haplotype analysis suggested two independent origins of the mutation. Pathological studies of an autopsied patient revealed TFG- and ubiquitin-immunopositive cytoplasmic inclusions in the spinal and cortical motor neurons. Fragmentation of the Golgi apparatus, a frequent finding in amyotrophic lateral sclerosis, was also observed in the motor neurons with inclusion bodies. Moreover, TAR DNA-binding protein 43 kDa (TDP-43)-positive cytoplasmic inclusions were also demonstrated. In cultured cells expressing mutant TFG, cytoplasmic aggregation of TDP-43 was demonstrated. These findings indicate that formation of TFG-containing cytoplasmic inclusions and concomitant mislocalization of TDP-43 underlie motor neuron degeneration in HMSN-P. Pathological overlap of proteinopathies involving TFG and TDP-43 highlights a new pathway leading to motor neuron degeneration.
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Affiliation(s)
- Hiroyuki Ishiura
- Department of Neurology, The University of Tokyo Graduate School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
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105
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Rutherford NJ, DeJesus-Hernandez M, Baker MC, Kryston TB, Brown PE, Lomen-Hoerth C, Boylan K, Wszolek ZK, Rademakers R. C9ORF72 hexanucleotide repeat expansions in patients with ALS from the Coriell Cell Repository. Neurology 2012; 79:482-3. [PMID: 22815561 DOI: 10.1212/wnl.0b013e31826170f1] [Citation(s) in RCA: 12] [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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106
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Brettschneider J, Toledo JB, Van Deerlin VM, Elman L, McCluskey L, Lee VMY, Trojanowski JQ. Microglial activation correlates with disease progression and upper motor neuron clinical symptoms in amyotrophic lateral sclerosis. PLoS One 2012; 7:e39216. [PMID: 22720079 PMCID: PMC3375234 DOI: 10.1371/journal.pone.0039216] [Citation(s) in RCA: 186] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 05/17/2012] [Indexed: 01/29/2023] Open
Abstract
Background/Aims We evaluated clinicopathological correlates of upper motor neuron (UMN) damage in amyotrophic lateral sclerosis (ALS), and analyzed if the presence of the C9ORF72 repeat expansion was associated with alterations in microglial inflammatory activity. Methods Microglial pathology was assessed by IHC with 2 different antibodies (CD68, Iba1), myelin loss by Kluver-Barrera staining and myelin basic protein (MBP) IHC, and axonal loss by neurofilament protein (TA51) IHC, performed on 59 autopsy cases of ALS including 9 cases with C9ORF72 repeat expansion. Results Microglial pathology as depicted by CD68 and Iba1 was significantly more extensive in the corticospinal tract (CST) of ALS cases with a rapid progression of disease. Cases with C9ORF72 repeat expansion showed more extensive microglial pathology in the medulla and motor cortex which persisted after adjusting for disease duration in a logistic regression model. Higher scores on the clinical UMN scale correlated with increasing microglial pathology in the cervical CST. TDP-43 pathology was more extensive in the motor cortex of cases with rapid progression of disease. Conclusions This study demonstrates that microglial pathology in the CST of ALS correlates with disease progression and is linked to severity of UMN deficits.
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Affiliation(s)
- Johannes Brettschneider
- Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America.
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107
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Widespread structural and functional connectivity changes in amyotrophic lateral sclerosis: insights from advanced neuroimaging research. Neural Plast 2012; 2012:473538. [PMID: 22720174 PMCID: PMC3377360 DOI: 10.1155/2012/473538] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 04/20/2012] [Accepted: 04/23/2012] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease principally affecting motor neurons. Besides motor symptoms, a subset of patients develop cognitive disturbances or even frontotemporal dementia (FTD), indicating that ALS may also involve extramotor brain regions. Both neuropathological and neuroimaging findings have provided further insight on the widespread effect of the neurodegeneration on brain connectivity and the underlying neurobiology of motor neurons degeneration. However, associated effects on motor and extramotor brain networks are largely unknown. Particularly, neuropathological findings suggest that ALS not only affects the frontotemporal network but rather is part of a wide clinicopathological spectrum of brain disorders known as TAR-DNA binding protein 43 (TDP-43) proteinopathies. This paper reviews the current state of knowledge concerning the neuropsychological and neuropathological sequelae of TDP-43 proteinopathies, with special focus on the neuroimaging findings associated with cognitive change in ALS.
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108
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Barker RA, Cicchetti F. Current understanding of the glial response to disorders of the aging CNS. Front Pharmacol 2012; 3:95. [PMID: 22654755 PMCID: PMC3361074 DOI: 10.3389/fphar.2012.00095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 05/01/2012] [Indexed: 12/13/2022] Open
Abstract
In this special issue of Frontiers in Pharmacology, we have asked leading experts to comment and review the evidence that inflammatory cells play a leading role in the pathological processes underlying neurodegenerative disorders. We now seek to draw these various observations together into a conclusion, with the hope that this will inform further work in this area and result in the identification of new therapeutic targets that will have a disease modifying effect.
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Affiliation(s)
- Roger A Barker
- Department of Clinical Neuroscience, Cambridge Centre for Brain Repair, University of Cambridge Cambridge, UK
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109
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Couthouis J, Hart MP, Erion R, King OD, Diaz Z, Nakaya T, Ibrahim F, Kim HJ, Mojsilovic-Petrovic J, Panossian S, Kim CE, Frackelton EC, Solski JA, Williams KL, Clay-Falcone D, Elman L, McCluskey L, Greene R, Hakonarson H, Kalb RG, Lee VMY, Trojanowski JQ, Nicholson GA, Blair IP, Bonini NM, Van Deerlin VM, Mourelatos Z, Shorter J, Gitler AD. Evaluating the role of the FUS/TLS-related gene EWSR1 in amyotrophic lateral sclerosis. Hum Mol Genet 2012; 21:2899-911. [PMID: 22454397 DOI: 10.1093/hmg/dds116] [Citation(s) in RCA: 210] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease affecting motor neurons. Mutations in related RNA-binding proteins TDP-43, FUS/TLS and TAF15 have been connected to ALS. These three proteins share several features, including the presence of a bioinformatics-predicted prion domain, aggregation-prone nature in vitro and in vivo and toxic effects when expressed in multiple model systems. Given these commonalities, we hypothesized that a related protein, EWSR1 (Ewing sarcoma breakpoint region 1), might also exhibit similar properties and therefore could contribute to disease. Here, we report an analysis of EWSR1 in multiple functional assays, including mutational screening in ALS patients and controls. We identified three missense variants in EWSR1 in ALS patients, which were absent in a large number of healthy control individuals. We show that disease-specific variants affect EWSR1 localization in motor neurons. We also provide multiple independent lines of in vitro and in vivo evidence that EWSR1 has similar properties as TDP-43, FUS and TAF15, including aggregation-prone behavior in vitro and ability to confer neurodegeneration in Drosophila. Postmortem analysis of sporadic ALS cases also revealed cytoplasmic mislocalization of EWSR1. Together, our studies highlight a potential role for EWSR1 in ALS, provide a collection of functional assays to be used to assess roles of additional RNA-binding proteins in disease and support an emerging concept that a class of aggregation-prone RNA-binding proteins might contribute broadly to ALS and related neurodegenerative diseases.
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Affiliation(s)
- Julien Couthouis
- Department of Genetics, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305, USA
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110
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High frequency of the expanded C9ORF72 hexanucleotide repeat in familial and sporadic Greek ALS patients. Neurobiol Aging 2012; 33:1851.e1-5. [PMID: 22445326 PMCID: PMC3657168 DOI: 10.1016/j.neurobiolaging.2012.02.021] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2012] [Revised: 02/19/2012] [Accepted: 02/19/2012] [Indexed: 11/20/2022]
Abstract
An intronic expansion of a hexanucleotide GGGGCC repeat in the C9ORF72 gene has recently been shown to be an important cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) in familial and sporadic cases. The frequency has only been defined in a small number of populations where the highest sporadic rate was identified in Finland (21.1%) and the lowest in mainland Italy (4.1%). We examined the C9ORF72 expansion in a series of 146 Greek ALS cases, 10.95% (n = 16) of cases carried the pathological expansion defined as greater than 30 repeats. In the 10 familial ALS probands, 50% (n = 5) of them carried a pathologically large expansion. In the remaining 136 sporadic ALS cases, 11 were carriers (8.2%). None of the 228 Greek controls carried an expanded repeat. The phenotype of our cases was spinal (13/16) or bulbar (3/16) ALS, the familial cases were all spinal ALS and none of our cases had behavioral frontotemporal dementia. Expansions in the C9ORF72 gene therefore represent a common cause of ALS in Greece and this test will be diagnostically very important to implement in the Greek population. The frequency is higher than other populations with the exception of Finland and this may be due to Greece being a relatively isolated population.
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111
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Microglial activation and TDP-43 pathology correlate with executive dysfunction in amyotrophic lateral sclerosis. Acta Neuropathol 2012; 123:395-407. [PMID: 22210083 DOI: 10.1007/s00401-011-0932-x] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 12/21/2011] [Accepted: 12/22/2011] [Indexed: 12/27/2022]
Abstract
While cognitive deficits are increasingly recognized as common symptoms in amyotrophic lateral sclerosis (ALS), the underlying histopathologic basis for this is not known, nor has the relevance of neuroinflammatory mechanisms and microglial activation to cognitive impairment (CI) in ALS been systematically analyzed. Staining for neurodegenerative disease pathology, TDP-43, and microglial activation markers (CD68, Iba1) was performed in 102 autopsy cases of ALS, and neuropathology data were related to clinical and neuropsychological measures. ALS with dementia (ALS-D) and ALS with impaired executive function (ALS-Ex) patients showed significant microglial activation in middle frontal and superior or middle temporal (SMT) gyrus regions, as well as significant neuronal loss and TDP-43 pathology in these regions. Microglial activation and TDP-43 pathology in middle frontal and superior or middle temporal regions were highly correlated with measures of executive impairment, but not with the MMSE. In contrast, only one ALS-D patient showed moderate Alzheimer's disease (AD) pathology. Tau and Aβ pathology increased with age. A lower MMSE score correlated with tau pathology in hippocampus and SMT gyrus, and with Aβ pathology in limbic and most cortical regions. Tau and Aβ pathology did not correlate with executive measures. We conclude that microglial activation and TDP-43 pathology in frontotemporal areas are determinants of FTLD spectrum dementia in ALS and correlate with neuropsychological measures of executive dysfunction. In contrast, AD pathology in ALS is primarily related to increasing age and associated with a poorer performance on the MMSE.
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112
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Ikenaka K, Katsuno M, Kawai K, Ishigaki S, Tanaka F, Sobue G. Disruption of axonal transport in motor neuron diseases. Int J Mol Sci 2012; 13:1225-1238. [PMID: 22312314 PMCID: PMC3269748 DOI: 10.3390/ijms13011225] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 01/11/2012] [Accepted: 01/16/2012] [Indexed: 12/29/2022] Open
Abstract
Motor neurons typically have very long axons, and fine-tuning axonal transport is crucial for their survival. The obstruction of axonal transport is gaining attention as a cause of neuronal dysfunction in a variety of neurodegenerative motor neuron diseases. Depletions in dynein and dynactin-1, motor molecules regulating axonal trafficking, disrupt axonal transport in flies, and mutations in their genes cause motor neuron degeneration in humans and rodents. Axonal transport defects are among the early molecular events leading to neurodegeneration in mouse models of amyotrophic lateral sclerosis (ALS). Gene expression profiles indicate that dynactin-1 mRNA is downregulated in degenerating spinal motor neurons of autopsied patients with sporadic ALS. Dynactin-1 mRNA is also reduced in the affected neurons of a mouse model of spinal and bulbar muscular atrophy, a motor neuron disease caused by triplet CAG repeat expansion in the gene encoding the androgen receptor. Pathogenic androgen receptor proteins also inhibit kinesin-1 microtubule-binding activity and disrupt anterograde axonal transport by activating c-Jun N-terminal kinase. Disruption of axonal transport also underlies the pathogenesis of spinal muscular atrophy and hereditary spastic paraplegias. These observations suggest that the impairment of axonal transport is a key event in the pathological processes of motor neuron degeneration and an important target of therapy development for motor neuron diseases.
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Affiliation(s)
- Kensuke Ikenaka
- Department of Neurology, Nagoya University Graduate School of Medicine. 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan; E-Mails: (K.I.); (K.K.); (F.T.)
| | - Masahisa Katsuno
- Department of Neurology, Nagoya University Graduate School of Medicine. 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan; E-Mails: (K.I.); (K.K.); (F.T.)
- Authors to whom correspondence should be addressed; E-Mails: (M.K.); (G.S.); Tel.: +81-52-744-2391 (M.K.); +81-52-744-2385 (G.S.); Fax: +81-52-744-2394 (M.K.); +81-52-744-2384 (G.S.)
| | - Kaori Kawai
- Department of Neurology, Nagoya University Graduate School of Medicine. 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan; E-Mails: (K.I.); (K.K.); (F.T.)
| | - Shinsuke Ishigaki
- Department of Neurology, Nagoya University Graduate School of Medicine. 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan; E-Mails: (K.I.); (K.K.); (F.T.)
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama 332-0012, Japan; E-Mail: (S.I.)
| | - Fumiaki Tanaka
- Department of Neurology, Nagoya University Graduate School of Medicine. 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan; E-Mails: (K.I.); (K.K.); (F.T.)
| | - Gen Sobue
- Department of Neurology, Nagoya University Graduate School of Medicine. 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan; E-Mails: (K.I.); (K.K.); (F.T.)
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama 332-0012, Japan; E-Mail: (S.I.)
- Authors to whom correspondence should be addressed; E-Mails: (M.K.); (G.S.); Tel.: +81-52-744-2391 (M.K.); +81-52-744-2385 (G.S.); Fax: +81-52-744-2394 (M.K.); +81-52-744-2384 (G.S.)
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113
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Papiani G, Ruggiano A, Fossati M, Raimondi A, Bertoni G, Francolini M, Benfante R, Navone F, Borgese N. Restructured Endoplasmic Reticulum, Generated by Mutant, Amyotrophic Lateral Sclerosis-Linked VAPB, is Cleared by the Proteasome. J Cell Sci 2012; 125:3601-11. [DOI: 10.1242/jcs.102137] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
VAPB (Vesicle-Associated Membrane Protein-Associated Protein B) is a ubiquitously expressed, ER-resident tail-anchored protein that functions as adaptor for lipid-exchange proteins. Its mutant form, P56S-VAPB, is linked to a dominantly inherited form of amyotrophic lateral sclerosis (ALS8). P56S-VAPB forms intracellular inclusions, whose role in ALS pathogenesis has not yet been elucidated. We recently demonstrated that these inclusions are formed by profoundly remodelled stacked ER cisternae (Fasana E. et al., FASEB J. 24:1419, 2010). Here, we used stable HeLa-TetOff cell lines inducibly expressing wild type and P56S-VAPB, as well as microinjection protocols in non-transfected cells, to investigate the dynamics of inclusion generation and degradation. Shortly after synthesis, the mutant protein forms small, polyubiquitinated clusters, which then congregate in the juxtanuclear region independently from the integrity of the microtubule cytoskeleton. The rate of degradation of the aggregated mutant is higher than that of the wild type protein, so that the inclusions are cleared only a few hours after cessation of P56S-VAPB synthesis. At variance with other inclusion bodies linked to neurodegenerative diseases, clearance of P56S-VAPB inclusions involves the proteasome, with no apparent participation of macro-autophagy. Transfection of a dominant negative form of the AAA ATPase, p97/VCP, stabilizes mutant VAPB, suggesting a role for this ATPase in extracting the aggregated protein from the inclusions. Our results demonstrate that the structures induced by P56S-VAPB stand apart from other inclusion bodies, both in the mechanism of their genesis and of their clearance from the cell, with possible implications for the pathogenic mechanism of the mutant protein.
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114
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Kovar H, Alonso J, Aman P, Aryee DNT, Ban J, Burchill SA, Burdach S, De Alava E, Delattre O, Dirksen U, Fourtouna A, Fulda S, Helman LJ, Herrero-Martin D, Hogendoorn PCW, Kontny U, Lawlor ER, Lessnick SL, Llombart-Bosch A, Metzler M, Moriggl R, Niedan S, Potratz J, Redini F, Richter GHS, Riedmann LT, Rossig C, Schäfer BW, Schwentner R, Scotlandi K, Sorensen PH, Staege MS, Tirode F, Toretsky J, Ventura S, Eggert A, Ladenstein R. The first European interdisciplinary ewing sarcoma research summit. Front Oncol 2012; 2:54. [PMID: 22662320 PMCID: PMC3361960 DOI: 10.3389/fonc.2012.00054] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 05/10/2012] [Indexed: 12/11/2022] Open
Abstract
The European Network for Cancer Research in Children and Adolescents (ENCCA) provides an interaction platform for stakeholders in research and care of children with cancer. Among ENCCA objectives is the establishment of biology-based prioritization mechanisms for the selection of innovative targets, drugs, and prognostic markers for validation in clinical trials. Specifically for sarcomas, there is a burning need for novel treatment options, since current chemotherapeutic treatment protocols have met their limits. This is most obvious for metastatic Ewing sarcoma (ES), where long term survival rates are still below 20%. Despite significant progress in our understanding of ES biology, clinical translation of promising laboratory results has not yet taken place due to fragmentation of research and lack of an institutionalized discussion forum. To fill this gap, ENCCA assembled 30 European expert scientists and five North American opinion leaders in December 2011 to exchange thoughts and discuss the state of the art in ES research and latest results from the bench, and to propose biological studies and novel promising therapeutics for the upcoming European EWING2008 and EWING2012 clinical trials.
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Affiliation(s)
- Heinrich Kovar
- Children’s Cancer Research Institute, St. Anna KinderkrebsforschungVienna, Austria
- Department of Pediatrics, Medical UniversityVienna, Austria
- *Correspondence: Heinrich Kovar, Children’s Cancer Research Institute, St. Anna Kinderkrebsforschung and Medical University, Zimmermannplatz 10, 1090 Vienna, Austria. e-mail:
| | - Javier Alonso
- Unidad de Tumores Sólidos Infantiles, Centro Nacional de Microbiología, Instituto de Salud Carlos IIIMajadahonda, Spain
| | - Pierre Aman
- Department of Pathology, Sahlgrenska Cancer Center, Sahlgrenska Academy at the University of GothenburgGothenburg, Sweden
| | - Dave N. T. Aryee
- Children’s Cancer Research Institute, St. Anna KinderkrebsforschungVienna, Austria
- Department of Pediatrics, Medical UniversityVienna, Austria
| | - Jozef Ban
- Children’s Cancer Research Institute, St. Anna KinderkrebsforschungVienna, Austria
| | | | - Stefan Burdach
- Children’s Cancer Research Center and Roman Herzog Comprehensive Cancer Center, Klinikum rechts der Isar, Technical UniversityMunich, Germany
| | - Enrique De Alava
- Department of Pathology, University Hospital of Salamanca, Cancer Research Center-IBMCC, University of Salamanca-CSICSalamanca, Spain
| | - Olivier Delattre
- INSERM, U830 Génétique et Biologie des CancersInstitut Curie, Paris, France
| | - Uta Dirksen
- Pediatric Hematology and Oncology, University Children’s Hospital MünsterMünster, Germany
| | - Argyro Fourtouna
- Children’s Cancer Research Institute, St. Anna KinderkrebsforschungVienna, Austria
| | - Simone Fulda
- Institute for Experimental Cancer Research in Pediatrics, Goethe-University FrankfurtFrankfurt am Main, Germany
| | - Lee J. Helman
- Molecular Oncology Section, Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of HealthBethesda, MD, USA
| | - David Herrero-Martin
- Children’s Cancer Research Institute, St. Anna KinderkrebsforschungVienna, Austria
| | | | - Udo Kontny
- Division of Pediatric Hematology and Oncology, University Children’s HospitalFreiburg, Germany
| | - Elizabeth R. Lawlor
- Department of Pediatrics, University of MichiganAnn Arbor, MI, USA
- Department of Pathology, University of MichiganAnn Arbor, MI, USA
| | - Stephen L. Lessnick
- Division of Pediatric Hematology and Oncology, Department of Oncological Sciences, Center for Children’s Cancer Research at Huntsman Cancer Institute, University of Utah School of MedicineSalt Lake City, UT, USA
| | | | | | - Richard Moriggl
- Ludwig Boltzmann Institute for Cancer ResearchVienna, Austria
| | - Stephan Niedan
- Children’s Cancer Research Institute, St. Anna KinderkrebsforschungVienna, Austria
| | - Jenny Potratz
- Pediatric Hematology and Oncology, University Children’s Hospital MünsterMünster, Germany
| | - Françoise Redini
- INSERM, UMR 957, LUNAM Université, Laboratoire de Physiopathologie de la Résorption Osseuse et Thérapie des Tumeurs Osseuses Primitives EA3822Nantes, France
| | - Günther H. S. Richter
- Children’s Cancer Research Center and Roman Herzog Comprehensive Cancer Center, Klinikum rechts der Isar, Technical UniversityMunich, Germany
| | - Lucia T. Riedmann
- Children’s Cancer Research Institute, St. Anna KinderkrebsforschungVienna, Austria
| | - Claudia Rossig
- Pediatric Hematology and Oncology, University Children’s Hospital MünsterMünster, Germany
| | - Beat W. Schäfer
- Department of Oncology, University Children’s HospitalZurich, Switzerland
| | - Raphaela Schwentner
- Children’s Cancer Research Institute, St. Anna KinderkrebsforschungVienna, Austria
| | - Katia Scotlandi
- CRS Development of Biomolecular Therapies, Laboratory of Experimental Oncology, Rizzoli InstituteBologna, Italy
| | - Poul H. Sorensen
- Department of Molecular Oncology, British Columbia Cancer Research CentreVancouver, BC, Canada
| | - Martin S. Staege
- Department of Pediatrics, Children’s Cancer Research Centre, Martin-Luther-University Halle-WittenbergHalle, Germany
| | - Franck Tirode
- INSERM, U830 Génétique et Biologie des CancersInstitut Curie, Paris, France
| | - Jeffrey Toretsky
- Lombardi Comprehensive Cancer Center, Georgetown UniversityWashington, DC, USA
| | - Selena Ventura
- Department of Oncology, University Children’s HospitalZurich, Switzerland
| | - Angelika Eggert
- Department of Pediatric Oncology and Hematology, University Children’s HospitalEssen, Germany
| | - Ruth Ladenstein
- Children’s Cancer Research Institute, St. Anna KinderkrebsforschungVienna, Austria
- Department of Pediatrics, Medical UniversityVienna, Austria
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