401
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Hagiwara K, Obayashi T, Sakayori N, Yamanishi E, Hayashi R, Osumi N, Nakazawa T, Nishida K. Molecular and cellular features of murine craniofacial and trunk neural crest cells as stem cell-like cells. PLoS One 2014; 9:e84072. [PMID: 24465393 PMCID: PMC3896334 DOI: 10.1371/journal.pone.0084072] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Accepted: 11/11/2013] [Indexed: 11/18/2022] Open
Abstract
The outstanding differentiation capacities and easier access from adult tissues, cells derived from neural crest cells (NCCs) have fascinated scientists in developmental biology and regenerative medicine. Differentiation potentials of NCCs are known to depend on their originating regions. Here, we report differential molecular features between craniofacial (cNCCs) and trunk (tNCCs) NCCs by analyzing transcription profiles and sphere forming assays of NCCs from P0-Cre/floxed-EGFP mouse embryos. We identified up-regulation of genes linked to carcinogenesis in cNCCs that were not previously reported to be related to NCCs, which was considered to be, an interesting feature in regard with carcinogenic potentials of NCCs such as melanoma and neuroblastoma. Wnt signal related genes were statistically up-regulated in cNCCs, also suggesting potential involvement of cNCCs in carcinogenesis. We also noticed intense expression of mesenchymal and neuronal markers in cNCCs and tNCCs, respectively. Consistent results were obtained from in vitro sphere-forming and differentiation assays. These results were in accordance with previous notion about differential potentials of cNCCs and tNCCs. We thus propose that sorting NCCs from P0-Cre/floxed-EGFP mice might be useful for the basic and translational research of NCCs. Furthermore, these newly-identified genes up-regulated in cNCC would provide helpful information on NC-originating tumors, developmental disorders in NCC derivatives, and potential applications of NCCs in regenerative medicine.
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Affiliation(s)
- Kunie Hagiwara
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Japan
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
| | - Takeshi Obayashi
- Division of Applied Informatics for Human and Life Science, Tohoku University Graduate School of Information Science, Aramaki-Aza-Aoba, Aoba-ku, Sendai, Japan
| | - Nobuyuki Sakayori
- Division of Developmental Neuroscience, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Japan
| | - Emiko Yamanishi
- Division of Developmental Neuroscience, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Japan
| | - Ryuhei Hayashi
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
| | - Noriko Osumi
- Division of Developmental Neuroscience, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Japan
- * E-mail:
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Japan
| | - Kohji Nishida
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Yamadaoka, Suita, Japan
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402
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Havrda MC, Paolella BR, Ran C, Jering KS, Wray CM, Sullivan JM, Nailor A, Hitoshi Y, Israel MA. Id2 mediates oligodendrocyte precursor cell maturation arrest and is tumorigenic in a PDGF-rich microenvironment. Cancer Res 2014; 74:1822-32. [PMID: 24425046 DOI: 10.1158/0008-5472.can-13-1839] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Maturation defects occurring in adult tissue progenitor cells have the potential to contribute to tumor development; however, there is little experimental evidence implicating this cellular mechanism in the pathogenesis of solid tumors. Inhibitor of DNA-binding 2 (Id2) is a transcription factor known to regulate the proliferation and differentiation of primitive stem and progenitor cells. Id2 is derepressed in adult tissue neural stem cells (NSC) lacking the tumor suppressor Tp53 and modulates their proliferation. Constitutive expression of Id2 in differentiating NSCs resulted in maturation-resistant oligodendroglial precursor cells (OPC), a cell population implicated in the initiation of glioma. Mechanistically, Id2 overexpression was associated with inhibition of the Notch effector Hey1, a bHLH transcription factor that we here characterize as a direct transcriptional repressor of the oligodendroglial lineage determinant Olig2. Orthotopic inoculation of NSCs with enhanced Id2 expression into brains of mice engineered to express platelet-derived growth factor in the central nervous system resulted in glioma. These data implicate a mechanism of altered NSC differentiation in glioma development and characterize a novel mouse model that reflects key characteristics of the recently described proneural subtype of glioblastoma multiforme. Such findings support the emerging concept that the cellular and molecular characteristics of tumor cells are linked to the transformation of distinct subsets of adult tissue progenitors.
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Affiliation(s)
- Matthew C Havrda
- Authors' Affiliations: Norris Cotton Cancer Center; Departments of Genetics; Pediatrics; and Pharmacology and Toxicology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
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403
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Sonabend AM, Bansal M, Guarnieri P, Lei L, Amendolara B, Soderquist C, Leung R, Yun J, Kennedy B, Sisti J, Bruce S, Bruce R, Shakya R, Ludwig T, Rosenfeld S, Sims PA, Bruce JN, Califano A, Canoll P. The transcriptional regulatory network of proneural glioma determines the genetic alterations selected during tumor progression. Cancer Res 2014; 74:1440-1451. [PMID: 24390738 DOI: 10.1158/0008-5472.can-13-2150] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Proneural glioblastoma is defined by an expression pattern resembling that of oligodendrocyte progenitor cells and carries a distinctive set of genetic alterations. Whether there is a functional relationship between the proneural phenotype and the associated genetic alterations is unknown. To evaluate this possible relationship, we performed a longitudinal molecular characterization of tumor progression in a mouse model of proneural glioma. In this setting, the tumors acquired remarkably consistent genetic deletions at late stages of progression, similar to those deleted in human proneural glioblastoma. Further investigations revealed that p53 is a master regulator of the transcriptional network underlying the proneural phenotype. This p53-centric transcriptional network and its associated phenotype were observed at both the early and late stages of progression, and preceded the proneural-specific deletions. Remarkably, deletion of p53 at the time of tumor initiation obviated the acquisition of later deletions, establishing a link between the proneural transcriptional network and the subtype-specific deletions selected during glioma progression.
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Affiliation(s)
- Adam M Sonabend
- Gabriele Bartoli Brain Tumor Laboratory, Department of Neurosurgery, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Mukesh Bansal
- Department of Systems Biology, Columbia University, New York, NY.,Center for Computational Biology and Bioinformatics, Columbia University, New York, NY
| | - Paolo Guarnieri
- Department of Systems Biology, Columbia University, New York, NY.,Center for Computational Biology and Bioinformatics, Columbia University, New York, NY
| | - Liang Lei
- Department of Pathology and Cell Biology, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Benjamin Amendolara
- Gabriele Bartoli Brain Tumor Laboratory, Department of Neurosurgery, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Craig Soderquist
- Department of Pathology and Cell Biology, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Richard Leung
- Department of Pathology and Cell Biology, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Jonathan Yun
- Gabriele Bartoli Brain Tumor Laboratory, Department of Neurosurgery, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Benjamin Kennedy
- Gabriele Bartoli Brain Tumor Laboratory, Department of Neurosurgery, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Julia Sisti
- Gabriele Bartoli Brain Tumor Laboratory, Department of Neurosurgery, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Samuel Bruce
- Gabriele Bartoli Brain Tumor Laboratory, Department of Neurosurgery, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Rachel Bruce
- Gabriele Bartoli Brain Tumor Laboratory, Department of Neurosurgery, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Reena Shakya
- Department of Molecular and Cellular Biochemistry, The Ohio State University Medical Center, Columbus, OH
| | - Thomas Ludwig
- Department of Molecular and Cellular Biochemistry, The Ohio State University Medical Center, Columbus, OH
| | - Steven Rosenfeld
- Brain Tumor and Neuro-Oncology Center, Cleveland Clinic, Cleveland, OH
| | - Peter A Sims
- Department of Systems Biology, Columbia University, New York, NY.,Department of Biochemistry & Molecular Biophysics, Columbia University Medical Center, New York, NY
| | - Jeffrey N Bruce
- Gabriele Bartoli Brain Tumor Laboratory, Department of Neurosurgery, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
| | - Andrea Califano
- Department of Systems Biology, Columbia University, New York, NY.,Center for Computational Biology and Bioinformatics, Columbia University, New York, NY.,Department of Biochemistry & Molecular Biophysics, Columbia University Medical Center, New York, NY.,Department of Biomedical Informatics, Columbia University, New York, NY.,Institute for Cancer Genetics, Columbia University, Columbia University, New York, NY.,Herbert Irving Comprehensive Cancer Center, Columbia University, New York, NY
| | - Peter Canoll
- Gabriele Bartoli Brain Tumor Laboratory, Department of Neurosurgery, Irving Research Cancer Center, Columbia University Medical Center, New York, NY.,Department of Pathology and Cell Biology, Irving Research Cancer Center, Columbia University Medical Center, New York, NY
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404
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Freeman MR, Rowitch DH. Evolving concepts of gliogenesis: a look way back and ahead to the next 25 years. Neuron 2013; 80:613-23. [PMID: 24183014 DOI: 10.1016/j.neuron.2013.10.034] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glial cells are present in all organisms with a CNS and, with increasing brain complexity, glial cells have undergone substantive increases in cell number, diversity, and functions. Invertebrates, such as Drosophila, possess glial subtypes with similarity to mammalian astrocytes in their basic morphology and function, representing fertile ground for unraveling fundamental aspects of glial biology. Although glial subtypes in simple organisms may be relatively homogenous, emerging evidence suggests the possibility that mammalian astrocytes might be highly diversified to match the needs of local neuronal subtypes. In this Perspective, we review classic and new roles identified for astrocytes and oligodendrocytes by recent studies. We propose that delineating genetic and developmental programs across species will be essential to understand the core functions of glia that allow enhanced neuronal function and to achieve new insights into glial roles in higher-order brain function and neurological disease.
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Affiliation(s)
- Marc R Freeman
- University of Massachusetts, and Howard Hughes Medical Institute, Worcester, MA 01605, USA.
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405
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Huang Y, Hoffman C, Rajappa P, Kim JH, Hu W, Huse J, Tang Z, Li X, Weksler B, Bromberg J, Lyden DC, Greenfield JP. Oligodendrocyte progenitor cells promote neovascularization in glioma by disrupting the blood-brain barrier. Cancer Res 2013; 74:1011-21. [PMID: 24371228 DOI: 10.1158/0008-5472.can-13-1072] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Enhanced platelet-derived growth factor (PDGF) signaling in glioma drives its development and progression. In this study, we define a unique role for stroma-derived PDGF signaling in maintaining tumor homeostasis within the glioma microenvironment. Large numbers of PDGF receptor-α (PDGFRα)-expressing stromal cells derived from oligodendrocytes progenitor cells (OPC) were discovered at the invasive front of high-grade gliomas, in which they exhibited a unique perivascular distribution. In PDGFRα-deficient host mice, in which orthotopic Gl261 tumors displayed reduced outgrowth, we found that tumor-associated blood vessels displayed smaller lumens and normalized vascular morphology, with tumors in host animals injected with the vascular imaging agent gadolinium also being enhanced less avidly by MRI. Notably, glioma-associated OPC promoted endothelial sprouting and tubule formation, in part by abrogating the inhibitory effect that perivascular astrocytes exert on vascular endothelial conjunctions. Stromal-derived PDGF-CC was crucial for the recruitment and activation of OPC, insofar as mice genetically deficient in PDGF-CC phenocopied the glioma/vascular defects observed in PDGFRα-deficient mice. Clinically, we showed that higher levels of PDGF-CC in glioma specimens were associated with more rapid disease recurrence and poorer overall survival. Our findings define a PDGFRα/PDGF-CC signaling axis within the glioma stromal microenvironment that contributes to vascular remodeling and aberrant tumor angiogenesis in the brain.
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Affiliation(s)
- Yujie Huang
- Authors' Affiliations: Department of Neurological Surgery, The Childhood Brain Tumor Project; Department of Pediatrics; Division of Hematology-Medical Oncology; Pediatric Brain Tumor Research, Children's Cancer and Blood Foundation Laboratories, Weill Cornell Medical College; Departments of Pathology and Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York; and National Eye Institute, NIH, Bethesda, Maryland
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406
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Yamada D, Hoshii T, Tanaka S, Hegazy AM, Kobayashi M, Tadokoro Y, Ohta K, Ueno M, Ali MAE, Hirao A. Loss of Tsc1 accelerates malignant gliomagenesis when combined with oncogenic signals. J Biochem 2013; 155:227-33. [PMID: 24368778 DOI: 10.1093/jb/mvt112] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Glioblastomas frequently harbour genetic lesions that stimulate the activity of mammalian target of rapamycin complex 1 (mTORC1). Loss of heterozygosity of tuberous sclerosis complex 1 (TSC1) or TSC2, which together form a critical negative regulator of mTORC1, is also seen in glioblastoma; however, it is not known how loss of the TSC complex affects the development of malignant gliomas. Here we investigated the role of Tsc1 in gliomagenesis in mice. Tsc1 deficiency up-regulated mTORC1 activity and suppressed the proliferation of neural stem/progenitor cells (NSPCs) in a serial neurosphere-forming assay, suggesting that Tsc1-deficient NSPCs have defective self-renewal activity. The neurosphere-forming capacity of Tsc1-deficient NSPCs was restored by p16(Ink4a)p19(Arf) deficiency. Combined Tsc1 and p16(Ink4a)p19(Arf) deficiency in NSPCs did not cause gliomagenesis in vivo. However, in a glioma model driven by an active mutant of epidermal growth factor receptor (EGFR), EGFRvIII, loss of Tsc1 resulted in an earlier onset of glioma development. The mTORC1 hyperactivation by Tsc1 deletion accelerated malignant phenotypes, including increased tumour mass and enhanced microvascular formation, leading to intracranial haemorrhage. These data demonstrate that, although mTORC1 hyperactivation itself may not be sufficient for gliomagenesis, it is a potent modifier of glioma development when combined with oncogenic signals.
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Affiliation(s)
- Daisuke Yamada
- Division of Molecular Genetics, Cancer and Stem Cell Research Program, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan
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407
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Oligodendrocyte/type-2 astrocyte progenitor cells and glial-restricted precursor cells generate different tumor phenotypes in response to the identical oncogenes. J Neurosci 2013; 33:16805-17. [PMID: 24133281 DOI: 10.1523/jneurosci.0546-13.2013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Despite the great interest in identifying the cell-of-origin for different cancers, little knowledge exists regarding the extent to which the specific origin of a tumor contributes to its properties. To directly examine this question, we expressed identical oncogenes in two types of glial progenitor cells, glial-restricted precursor (GRP) cells and oligodendrocyte/type-2 astrocyte progenitor cells (O-2A/OPCs), and in astrocytes of the mouse CNS (either directly purified or generated from GRP cells). In vitro, expression of identical oncogenes in these cells generated populations differing in expression of antigens thought to identify tumor initiating cells, generation of 3D aggregates when grown as adherent cultures, and sensitivity to the chemotherapeutic agent BCNU. In vivo, cells differed in their ability to form tumors, in malignancy and even in the type of host-derived cells infiltrating the tumor mass. Moreover, identical genetic modification of these different cells yielded benign infiltrative astrocytomas, malignant astrocytomas, or tumors with characteristics seen in oligodendrogliomas and small-cell astrocytomas, indicating a contribution of cell-of-origin to the characteristic properties expressed by these different tumors. Our studies also revealed unexpected relationships between the cell-of-origin, differentiation, and the order of oncogene acquisition at different developmental stages in enabling neoplastic growth. These studies thus provide multiple novel demonstrations of the importance of the cell-of-origin in respect to the properties of transformed cells derived from them. In addition, the approaches used enable analysis of the role of cell-of-origin in tumor biology in ways that are not accessible by other more widely used approaches.
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408
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Komori H, Xiao Q, McCartney BM, Lee CY. Brain tumor specifies intermediate progenitor cell identity by attenuating β-catenin/Armadillo activity. Development 2013; 141:51-62. [PMID: 24257623 DOI: 10.1242/dev.099382] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
During asymmetric stem cell division, both the daughter stem cell and the presumptive intermediate progenitor cell inherit cytoplasm from their parental stem cell. Thus, proper specification of intermediate progenitor cell identity requires an efficient mechanism to rapidly extinguish the activity of self-renewal factors, but the mechanisms remain unknown in most stem cell lineages. During asymmetric division of a type II neural stem cell (neuroblast) in the Drosophila larval brain, the Brain tumor (Brat) protein segregates unequally into the immature intermediate neural progenitor (INP), where it specifies INP identity by attenuating the function of the self-renewal factor Klumpfuss (Klu), but the mechanisms are not understood. Here, we report that Brat specifies INP identity through its N-terminal B-boxes via a novel mechanism that is independent of asymmetric protein segregation. Brat-mediated specification of INP identity is critically dependent on the function of the Wnt destruction complex, which attenuates the activity of β-catenin/Armadillo (Arm) in immature INPs. Aberrantly increasing Arm activity in immature INPs further exacerbates the defects in the specification of INP identity and enhances the supernumerary neuroblast mutant phenotype in brat mutant brains. By contrast, reducing Arm activity in immature INPs suppresses supernumerary neuroblast formation in brat mutant brains. Finally, reducing Arm activity also strongly suppresses supernumerary neuroblasts induced by overexpression of klu. Thus, the Brat-dependent mechanism extinguishes the function of the self-renewal factor Klu in the presumptive intermediate progenitor cell by attenuating Arm activity, balancing stem cell maintenance and progenitor cell specification.
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Affiliation(s)
- Hideyuki Komori
- Center for Stem Cell Biology, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
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409
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Teng X, Dayhoff-Brannigan M, Cheng WC, Gilbert CE, Sing CN, Diny NL, Wheelan SJ, Dunham MJ, Boeke JD, Pineda FJ, Hardwick JM. Genome-wide consequences of deleting any single gene. Mol Cell 2013; 52:485-94. [PMID: 24211263 DOI: 10.1016/j.molcel.2013.09.026] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 08/18/2013] [Accepted: 09/19/2013] [Indexed: 11/19/2022]
Abstract
Loss or duplication of chromosome segments can lead to further genomic changes associated with cancer. However, it is not known whether only a select subset of genes is responsible for driving further changes. To determine whether perturbation of any given gene in a genome suffices to drive subsequent genetic changes, we analyzed the yeast knockout collection for secondary mutations of functional consequence. Unlike wild-type, most gene knockout strains were found to have one additional mutant gene affecting nutrient responses and/or heat-stress-induced cell death. Moreover, independent knockouts of the same gene often evolved mutations in the same secondary gene. Genome sequencing identified acquired mutations in several human tumor suppressor homologs. Thus, mutation of any single gene may cause a genomic imbalance, with consequences sufficient to drive adaptive genetic changes. This complicates genetic analyses but is a logical consequence of losing a functional unit originally acquired under pressure during evolution.
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Affiliation(s)
- Xinchen Teng
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
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410
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Jha MK, Seo M, Kim JH, Kim BG, Cho JY, Suk K. The secretome signature of reactive glial cells and its pathological implications. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:2418-28. [PMID: 23269363 DOI: 10.1016/j.bbapap.2012.12.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 11/23/2012] [Accepted: 12/12/2012] [Indexed: 12/12/2022]
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411
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Stacpoole S, Spitzer S, Bilican B, Compston A, Karadottir R, Chandran S, Franklin R. High yields of oligodendrocyte lineage cells from human embryonic stem cells at physiological oxygen tensions for evaluation of translational biology. Stem Cell Reports 2013; 1:437-50. [PMID: 24286031 PMCID: PMC3841262 DOI: 10.1016/j.stemcr.2013.09.006] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Revised: 09/26/2013] [Accepted: 09/27/2013] [Indexed: 02/09/2023] Open
Abstract
We have established and efficient system to specify NG2/PDGF-Rα/OLIG2+ oligodendrocyte precursor cells (OPCs) from human embryonic stem cells (hESCs) at low, physiological (3%) oxygen levels. This was achieved via both forebrain and spinal cord origins, with up to 98% of cells expressing NG2. Developmental insights reveal a critical role for fibroblast growth factor 2 (FGF-2) in OLIG2 induction via ventral forebrain pathways. The OPCs mature in vitro to express O4 (46%) and subsequently become galactocerebroside (GALC), O1, and myelin basic protein-positive (MBP+) multibranching oligodendrocytes. These were cultured alongside hESC-derived neurons. The electrophysiological properties of human OPCs are similar to those of rat OPCs, with large voltage-gated sodium currents and the ability to fire action potentials. Exposure to a selective retinoid X receptor agonist increased the proportion of O4+ oligodendrocytes that express MBP from 5% to 30%. Thus, we have established a developmentally engineered system to investigate the biological properties of human OPCs and test the effects of putative remyelinating agents prior to clinical application.
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Affiliation(s)
- Sybil R.L. Stacpoole
- Department of Clinical Neurosciences, Cambridge University, Cambridge CB2 0PY, UK
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute and Department of Veterinary Medicine, Cambridge University, Cambridge CB3 0ES, UK
| | - Sonia Spitzer
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute and Department of Veterinary Medicine, Cambridge University, Cambridge CB3 0ES, UK
| | - Bilada Bilican
- Centre for Neuroregeneration, Edinburgh University, Edinburgh EH16 4SB, UK
| | - Alastair Compston
- Department of Clinical Neurosciences, Cambridge University, Cambridge CB2 0PY, UK
| | - Ragnhildur Karadottir
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute and Department of Veterinary Medicine, Cambridge University, Cambridge CB3 0ES, UK
| | | | - Robin J.M. Franklin
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute and Department of Veterinary Medicine, Cambridge University, Cambridge CB3 0ES, UK
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412
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Zhang B, Dai M, Li QJ, Zhuang Y. Tracking proliferative history in lymphocyte development with cre-mediated sister chromatid recombination. PLoS Genet 2013; 9:e1003887. [PMID: 24204301 PMCID: PMC3814321 DOI: 10.1371/journal.pgen.1003887] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 09/03/2013] [Indexed: 11/18/2022] Open
Abstract
Tracking and isolating live cells based on their proliferative history in live animals remains a technical challenge in animal studies. We have designed a genetic marking system for tracking the proliferative frequency and history of lymphocytes during their development and homeostatic maintenance. This system is based on activation of a fluorescent marker after Cre-dependent recombination between sister chromatids at a specially designed tandem loxP site, named Tlox. We have demonstrated the utility of the Tlox system in tracking proliferative windows of B and T lymphocyte development. We have further applied the Tlox system in the analysis of the proliferative behavior and homeostatic maintenance of Vγ1.1 positive γδ T cells. Our data show that Vγ1.1 T cells generated in neonatal but not adult life are able to expand in the thymus. The expanded Vγ1.1 T cells are preferentially maintained in the liver but not in lymphoid organs. It has been shown that numbers of Vγ1.1 T cells were dramatically increased in the lymphoid organs of Id3 deficient mice. By combining BrdU and Tlox assays we show that this phenotype is primarily due to enhanced neonatal expansion and subsequent retention of Vγ1.1 T cells. Thus, the Tlox system provides a new genetic tool to track clonal expansion within a defined cell population or tissue type in live animals.
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Affiliation(s)
- Baojun Zhang
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Meifang Dai
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Qi-Jing Li
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail: (QJL); (YZ)
| | - Yuan Zhuang
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail: (QJL); (YZ)
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413
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Hide T, Makino K, Nakamura H, Yano S, Anai S, Takezaki T, Kuroda JI, Shinojima N, Ueda Y, Kuratsu JI. New treatment strategies to eradicate cancer stem cells and niches in glioblastoma. Neurol Med Chir (Tokyo) 2013; 53:764-72. [PMID: 24140771 PMCID: PMC4508715 DOI: 10.2176/nmc.ra2013-0207] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Glioblastoma multiforme (GBM) harbors are not only rapidly dividing cells but also small populations of slowly dividing and dormant cells with tumorigenesity, self-renewal, and multi-lineage differentiation capabilities. Known as glioblastoma stem cells (GSCs), they are resistant to conventional chemo- and radiotherapy and may be a causative factor in recurrence. The treatment outcome in patients with GBM remains unsatisfactory and their mean survival time has not improved sufficiently. We studied clinical evidence and basic research findings to assess the possibility of new treatment strategies that target GSCs and their specific microenvironments (GBM niches) and raise the possibility of adding new treatments to eradicate GSCs and GBM niches.
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Affiliation(s)
- Takuichiro Hide
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
- Address reprint requests to: Takuichiro Hide, MD, PhD, Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, 1-1-1 Honjo, Chuo-ku, Kumamoto, Kumamoto 860-8556, Japan. e-mail:
| | - Keishi Makino
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
| | - Hideo Nakamura
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
| | - Shigetoshi Yano
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
| | - Shigeo Anai
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
| | - Tatsuya Takezaki
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
| | - Jun-ichiro Kuroda
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
| | - Naoki Shinojima
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
| | - Yutaka Ueda
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
| | - Jun-ichi Kuratsu
- Department of Neurosurgery, Kumamoto University Graduate School of Medical Science, Kumamoto, Kumamoto
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414
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Henner A, Ventura PB, Jiang Y, Zong H. MADM-ML, a mouse genetic mosaic system with increased clonal efficiency. PLoS One 2013; 8:e77672. [PMID: 24143253 PMCID: PMC3797059 DOI: 10.1371/journal.pone.0077672] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 09/11/2013] [Indexed: 01/07/2023] Open
Abstract
Mosaic Analysis with Double Markers (MADM) is a mouse genetic system that allows simultaneous gene knockout and fluorescent labeling of sparse, clonally-related cells within an otherwise normal mouse, thereby circumventing embryonic lethality problems and providing single-cell resolution for phenotypic analysis in vivo. The clonal efficiency of MADM is intrinsically low because it relies on Cre/loxP-mediated mitotic recombination between two homologous chromosomes rather than within the same chromosome, as in the case of conditional knockout (CKO). Although sparse labeling enhances in vivo resolution, the original MADM labels too few or even no cells when a low-expressing Cre transgene is used or a small population of cells is studied. Recently, we described the usage of a new system, MADM-ML, which contains three mutually exclusive, self-recognizing loxP variant sites as opposed to a single loxP site present in the original MADM system (referred to as MADM-SL in this paper). Here we carefully compared the recombination efficiency between MADM-SL and MADM-ML using the same Cre transgene, and found that the new system labels significantly more cells than the original system does. When we established mouse medulloblastoma models with both the original and the new MADM systems, we found that, while the MADM-SL model suffered from varied tumor progression and incomplete penetrance, the MADM-ML model had consistent tumor progression and full penetrance of tumor formation. Therefore MADM-ML, with its higher recombination efficiency, will broaden the applicability of MADM for studying many biological questions including normal development and disease modeling at cellular resolution in vivo.
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Affiliation(s)
- Astra Henner
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, United States of America
| | - P. Britten Ventura
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, United States of America
| | - Ying Jiang
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, United States of America
| | - Hui Zong
- Institute of Molecular Biology, University of Oregon, Eugene, Oregon, United States of America
- * E-mail:
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415
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Sharifi K, Ebrahimi M, Kagawa Y, Islam A, Tuerxun T, Yasumoto Y, Hara T, Yamamoto Y, Miyazaki H, Tokuda N, Yoshikawa T, Owada Y. Differential expression and regulatory roles of FABP5 and FABP7 in oligodendrocyte lineage cells. Cell Tissue Res 2013; 354:683-95. [PMID: 24114376 DOI: 10.1007/s00441-013-1730-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 09/05/2013] [Indexed: 12/15/2022]
Abstract
Fatty-acid-binding proteins (FABPs) are key intracellular molecules involved in the uptake, transportation and storage of fatty acids and in the mediation of signal transduction and gene transcription. However, little is known regarding their expression and function in the oligodendrocyte lineage. We evaluate the in vivo and in vitro expression of FABP5 and FABP7 in oligodendrocyte lineage cells in the cortex and corpus callosum of adult mice, mixed cortical culture and oligosphere culture by immunofluorescent counter-staining with major oligodendrocyte lineage markers. In all settings, FABP7 expression was detected in NG2(+)/PDGFRα(+) oligodendrocyte progenitor cells (OPCs) that did not express FABP5. FABP5 was detected in mature CC1(+)/MBP(+) oligodendrocytes that did not express FABP7. Analysis of cultured OPCs showed a significant decrease in the population of FABP7-knockout (KO) OPCs and their BrdU uptake compared with wild-type (WT) OPCs. Upon incubation of OPCs in oligodendrocyte differentiation medium, a significantly lower percentage of FABP7-KO OPCs differentiated into O4(+) oligodendrocytes. The percentage of mature MBP(+) oligodendrocytes relative to whole O4(+)/MBP(+) oligodendrocytes was significantly lower in FABP7-KO and FABP5-KO than in WT cell populations. The percentage of terminally mature oligodendrocytes with membrane sheet morphology was significantly lower in FABP5-KO compared with WT cell populations. Thus, FABP7 and FABP5 are differentially expressed in oligodendrocyte lineage cells and regulate their proliferation and/or differentiation. Our findings suggest the involvement of FABP7 and FABP5 in the pathophysiology of demyelinating disorders, neuropsychiatric disorder and glioma, conditions in which OPCs/oligodendrocytes play central roles.
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Affiliation(s)
- Kazem Sharifi
- Department of Organ Anatomy, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube, 755-8505, Japan
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416
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Macara IG, McCaffrey L. Cell polarity in morphogenesis and metastasis. Philos Trans R Soc Lond B Biol Sci 2013; 368:20130012. [PMID: 24062582 DOI: 10.1098/rstb.2013.0012] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Most human cancers arise either from epithelial cells or their progenitors. Epithelial cells possess a distinctive apical-basal polarity and loss of polarity is frequently assumed to be a common feature of cancer progression. In particular, cancer cell dissemination to ectopic sites, and metastatic growth at those sites, is often considered to require a mesenchymal transition in which the transformed epithelial cells lose their apical-basal polarity. However, many cancers retain epithelial characteristics, and until recently there has been little conclusive evidence for an involvement of the cell polarity machinery in tumour growth and metastasis. In this article, we discuss evidence that polarity proteins can be potent invasion suppressors but that loss of epithelial character is not essential either for tumour growth and invasion, or metastatic colonization.
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Affiliation(s)
- Ian G Macara
- Department of Cell and Developmental Biology, Vanderbilt University, , Nashville, TN 37215, USA
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417
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Bhat KP, Balasubramaniyan V, Vaillant B, Ezhilarasan R, Hummelink K, Hollingsworth F, Wani K, Heathcock L, James JD, Goodman LD, Conroy S, Long L, Lelic N, Wang S, Gumin J, Raj D, Kodama Y, Raghunathan A, Olar A, Joshi K, Pelloski CE, Heimberger A, Kim SH, Cahill DP, Rao G, Den Dunnen WF, Boddeke HW, Phillips HS, Nakano I, Lang FF, Colman H, Sulman EP, Aldape K. Mesenchymal differentiation mediated by NF-κB promotes radiation resistance in glioblastoma. Cancer Cell 2013; 24:331-46. [PMID: 23993863 PMCID: PMC3817560 DOI: 10.1016/j.ccr.2013.08.001] [Citation(s) in RCA: 773] [Impact Index Per Article: 70.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 06/24/2013] [Accepted: 08/01/2013] [Indexed: 01/08/2023]
Abstract
Despite extensive study, few therapeutic targets have been identified for glioblastoma (GBM). Here we show that patient-derived glioma sphere cultures (GSCs) that resemble either the proneural (PN) or mesenchymal (MES) transcriptomal subtypes differ significantly in their biological characteristics. Moreover, we found that a subset of the PN GSCs undergoes differentiation to a MES state in a TNF-α/NF-κB-dependent manner with an associated enrichment of CD44 subpopulations and radioresistant phenotypes. We present data to suggest that the tumor microenvironment cell types such as macrophages/microglia may play an integral role in this process. We further show that the MES signature, CD44 expression, and NF-κB activation correlate with poor radiation response and shorter survival in patients with GBM.
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Affiliation(s)
- Krishna P.L. Bhat
- Department of Pathology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
- Correspondence: ; ;
| | - Veerakumar Balasubramaniyan
- Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, 9713 AV, The Netherlands
| | | | - Ravesanker Ezhilarasan
- Department of Radiation Oncology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Karlijn Hummelink
- Department of Pathology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Faith Hollingsworth
- Department of Pathology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Khalida Wani
- Department of Pathology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Lindsey Heathcock
- Department of Pathology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Johanna D. James
- Department of Pathology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Lindsey D. Goodman
- Department of Radiation Oncology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Siobhan Conroy
- Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, 9713 AV, The Netherlands
| | - Lihong Long
- Department of Pathology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Nina Lelic
- Deparment of Neurosurgery, Massachusetts General Hospital/Brain Tumor Center, Boston, MA 02114, USA
| | - Suzhen Wang
- Department of Neuro-oncology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Joy Gumin
- Department of Neurosurgery, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Divya Raj
- Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, 9713 AV, The Netherlands
| | - Yoshinori Kodama
- Division of Pathology, Osaka National Hospital, National Hospital Organization, Chuo-ku, Osaka 540-0006, Japan
| | | | - Adriana Olar
- Department of Pathology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Kaushal Joshi
- Department of Neurosurgery, The Ohio State University, Columbus, OH 43210, USA
| | | | - Amy Heimberger
- Department of Neurosurgery, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Se Hoon Kim
- Department of Pathology, Yonsei University College of Medicine, Seoul, 120-752, Korea
| | - Daniel P. Cahill
- Deparment of Neurosurgery, Massachusetts General Hospital/Brain Tumor Center, Boston, MA 02114, USA
| | - Ganesh Rao
- Department of Neurosurgery, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Wilfred F.A. Den Dunnen
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, 9700 RB, The Netherlands
| | - Hendrikus W.G.M. Boddeke
- Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, 9713 AV, The Netherlands
| | - Heidi S. Phillips
- Department of Tumor Biology and Angiogenesis, Genentech, Inc., South San Francisco, CA 94080, USA
| | - Ichiro Nakano
- Department of Neurosurgery, The Ohio State University, Columbus, OH 43210, USA
| | - Frederick F. Lang
- Department of Neurosurgery, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Howard Colman
- Department of Neurosurgery, and Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84132, USA
| | - Erik P. Sulman
- Department of Radiation Oncology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
- Correspondence: ; ;
| | - Kenneth Aldape
- Department of Pathology, The University of Texas, M.D. Anderson Cancer Center, Houston, TX 77030, USA
- Correspondence: ; ;
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418
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Hippenmeyer S. Dissection of gene function at clonal level using mosaic analysis with double markers. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s11515-013-1279-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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419
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Muñoz DM, Tung T, Agnihotri S, Singh S, Guha A, Zadeh G, Hawkins C. Loss of p53 cooperates with K-ras activation to induce glioma formation in a region-independent manner. Glia 2013; 61:1862-72. [PMID: 24038521 DOI: 10.1002/glia.22563] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 07/15/2013] [Accepted: 07/17/2013] [Indexed: 11/09/2022]
Abstract
Gliomas are recognized as a heterogeneous group of neoplasms differing in their location and morphological features. These differences, between and within varying grades of gliomas, have not been explained solely on the grounds of an oncogenic stimulus. Interactions with the tumor microenvironment as well as inherent characteristics of the cell of origin are likely a source of this heterogeneity. There is an ongoing debate over the cell of origin of gliomas, where some suggest a progenitor, while others argue for a stem cell origin. Thus, it is presumed that neurogenic regions of the brain such as the subventricular zone (SVZ) containing large numbers of neural stem and progenitor populations are more susceptible to transformation. Our studies demonstrate that K-ras(G12D) cooperates with the loss of p53 to induce gliomas from both the SVZ and cortical region, suggesting that cells in the SVZ are not uniquely gliomagenic. Using combinations of doxycycline-inducible K-ras(G12D) and p53 loss, we show that tumors induced by the cooperative actions of these genes remain dependent on active K-ras expression, as deinduction of K-ras(G12D) leads to complete tumor regression despite absence of p53. These results suggest that the interplay between specific combinations of genetic alterations and susceptible cell types, rather than the site of origin, are important determinates of gliomagenesis. Additionally, this model supports the view that, although several genetic events may be necessary to confer traits associated with oncogenic transformation, inactivation of a single oncogenic partner can undermine tumor maintenance, leading to regression and disease remission.
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Affiliation(s)
- Diana Marcela Muñoz
- The Arthur and Sonia Labatt Brain Tumor Research Centre, Hospital for Sick Children Research Institute, University of Toronto, Toronto, ON, Canada
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420
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Goffart N, Kroonen J, Rogister B. Glioblastoma-initiating cells: relationship with neural stem cells and the micro-environment. Cancers (Basel) 2013; 5:1049-71. [PMID: 24202333 PMCID: PMC3795378 DOI: 10.3390/cancers5031049] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 07/29/2013] [Accepted: 08/01/2013] [Indexed: 01/19/2023] Open
Abstract
Glioblastoma multiforme (GBM, WHO grade IV) is the most common and lethal subtype of primary brain tumor with a median overall survival of 15 months from the time of diagnosis. The presence in GBM of a cancer population displaying neural stem cell (NSC) properties as well as tumor-initiating abilities and resistance to current therapies suggests that these glioblastoma-initiating cells (GICs) play a central role in tumor development and are closely related to NSCs. However, it is nowadays still unclear whether GICs derive from NSCs, neural progenitor cells or differentiated cells such as astrocytes or oligodendrocytes. On the other hand, NSCs are located in specific regions of the adult brain called neurogenic niches that have been shown to control critical stem cell properties, to nourish NSCs and to support their self-renewal. This “seed-and-soil” relationship has also been adapted to cancer stem cell research as GICs also require a specific micro-environment to maintain their “stem cell” properties. In this review, we will discuss the controversies surrounding the origin and the identification of GBM stem cells and highlight the micro-environment impact on their biology.
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Affiliation(s)
- Nicolas Goffart
- Laboratory of Developmental Neurobiology, GIGA-Neurosciences Research Center, University of Liège, Liège 4000, Belgium; E-Mail:
| | - Jérôme Kroonen
- Human Genetics, CHU and University of Liège, Liège 4000, Belgium; E-Mail:
- The T&P Bohnenn Laboratory for Neuro-Oncology, Department of Neurology and Neurosurgery, UMC Utrecht, Utrecht 3556, The Netherlands; E-Mail:
| | - Bernard Rogister
- Laboratory of Developmental Neurobiology, GIGA-Neurosciences Research Center, University of Liège, Liège 4000, Belgium; E-Mail:
- Department of Neurology, CHU and University of Liège, Liège 4000, Belgium
- GIGA-Development, Stem Cells and Regenerative Medicine, University of Liège, Liège 4000, Belgium
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +32-4-366-5950; Fax: +32-4-366-5912
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421
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Snyder CS, Harrington AR, Kaushal S, Mose E, Lowy AM, Hoffman RM, Bouvet M. A dual-color genetically engineered mouse model for multispectral imaging of the pancreatic microenvironment. Pancreas 2013; 42:952-8. [PMID: 23648841 PMCID: PMC3713119 DOI: 10.1097/mpa.0b013e31828643df] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVES To develop a mouse model for multispectral fluorescence imaging of the pancreas and pancreatic microenvironment. METHODS Cre/loxP technology was used to develop this model. We crossed mT/mG indicator mice, engineered to constitutively express a conditional tdTomato transgene that converts to green fluorescent protein (GFP) expression after exposure to Cre recombinase, with Pdx1-Cre transgenic mice. To characterize this model for studies of pancreas biology, we performed bright light and fluorescence imaging of body cavities and intact organs and confocal microscopy of pancreata from offspring of Pdx1-Cre and mT/mG crosses. RESULTS Pdx1-Cre-mT/mG mice demonstrated bright GFP expression within the pancreas and duodenum and intense tdTomato expression in all other organs. Green fluorescent protein expression was mosaic in Pdx1-Cre-mT/mG pancreata, with most showing extensive conversion from tdTomato to GFP expression within the epithelial-derived elements of the pancreatic parenchyma. Because both GFP and tdTomato are membrane targeted, individual cell borders were clearly outlined in confocal images of mT/mG pancreata. CONCLUSIONS This mouse model enables multispectral fluorescence imaging of individual cells and cell processes at the microscopic level of the pancreatic microenvironment; it should prove valuable for a variety of fluorescence imaging studies, ranging from pancreatic development to pancreatic cancer biology.
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Affiliation(s)
- Cynthia S Snyder
- Department of Surgery, UCSD Moores Cancer Center, La Jolla, CA 92093-0987, USA
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422
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Long PM, Moffett JR, Namboodiri AMA, Viapiano MS, Lawler SE, Jaworski DM. N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) promote growth and inhibit differentiation of glioma stem-like cells. J Biol Chem 2013; 288:26188-26200. [PMID: 23884408 DOI: 10.1074/jbc.m113.487553] [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] [Indexed: 12/15/2022] Open
Abstract
Metabolic reprogramming is a pathological feature of cancer and a driver of tumor cell transformation. N-Acetylaspartate (NAA) is one of the most abundant amino acid derivatives in the brain and serves as a source of metabolic acetate for oligodendrocyte myelination and protein/histone acetylation or a precursor for the synthesis of the neurotransmitter N-acetylaspartylglutamate (NAAG). NAA and NAAG as well as aspartoacylase (ASPA), the enzyme responsible for NAA degradation, are significantly reduced in glioma tumors, suggesting a possible role for decreased acetate metabolism in tumorigenesis. This study sought to examine the effects of NAA and NAAG on primary tumor-derived glioma stem-like cells (GSCs) from oligodendroglioma as well as proneural and mesenchymal glioblastoma, relative to oligodendrocyte progenitor cells (Oli-Neu). Although the NAA dicarboxylate transporter NaDC3 is primarily thought to be expressed by astrocytes, all cell lines expressed NaDC3 and, thus, are capable of NAA up-take. Treatment with NAA or NAAG significantly increased GSC growth and suppressed differentiation of Oli-Neu cells and proneural GSCs. Interestingly, ASPA was expressed in both the cytosol and nuclei of GSCs and exhibited greatest nuclear immunoreactivity in differentiation-resistant GSCs. Both NAA and NAAG elicited the expression of a novel immunoreactive ASPA species in select GSC nuclei, suggesting differential ASPA regulation in response to these metabolites. Therefore, this study highlights a potential role for nuclear ASPA expression in GSC malignancy and suggests that the use of NAA or NAAG is not an appropriate therapeutic approach to increase acetate bioavailability in glioma. Thus, an alternative acetate source is required.
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Affiliation(s)
- Patrick M Long
- From the Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, Vermont 05405
| | - John R Moffett
- the Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, and
| | - Aryan M A Namboodiri
- the Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, and
| | - Mariano S Viapiano
- the Department of Neurosurgery, Brigham and Women's Hospital, Boston, Massachusetts 02215
| | - Sean E Lawler
- the Department of Neurosurgery, Brigham and Women's Hospital, Boston, Massachusetts 02215
| | - Diane M Jaworski
- From the Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, Vermont 05405,.
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423
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Auvergne RM, Sim FJ, Wang S, Chandler-Militello D, Burch J, Al Fanek Y, Davis D, Benraiss A, Walter K, Achanta P, Johnson M, Quinones-Hinojosa A, Natesan S, Ford HL, Goldman SA. Transcriptional differences between normal and glioma-derived glial progenitor cells identify a core set of dysregulated genes. Cell Rep 2013; 3:2127-41. [PMID: 23727239 PMCID: PMC5293199 DOI: 10.1016/j.celrep.2013.04.035] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Revised: 03/17/2013] [Accepted: 04/29/2013] [Indexed: 01/15/2023] Open
Abstract
Glial progenitor cells (GPCs) are a potential source of malignant gliomas. We used A2B5-based sorting to extract tumorigenic GPCs from human gliomas spanning World Health Organization grades II-IV. Messenger RNA profiling identified a cohort of genes that distinguished A2B5+ glioma tumor progenitor cells (TPCs) from A2B5+ GPCs isolated from normal white matter. A core set of genes and pathways was substantially dysregulated in A2B5+ TPCs, which included the transcription factor SIX1 and its principal cofactors, EYA1 and DACH2. Small hairpin RNAi silencing of SIX1 inhibited the expansion of glioma TPCs in vitro and in vivo, suggesting a critical and unrecognized role of the SIX1-EYA1-DACH2 system in glioma genesis or progression. By comparing the expression patterns of glioma TPCs with those of normal GPCs, we have identified a discrete set of pathways by which glial tumorigenesis may be better understood and more specifically targeted.
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Affiliation(s)
- Romane M Auvergne
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY 14642, USA.
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424
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Clarke J, Penas C, Pastori C, Komotar RJ, Bregy A, Shah AH, Wahlestedt C, Ayad NG. Epigenetic pathways and glioblastoma treatment. Epigenetics 2013; 8:785-95. [PMID: 23807265 PMCID: PMC3883781 DOI: 10.4161/epi.25440] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Glioblastoma multiforme (GBM) is the most common malignant adult brain tumor. Standard GBM treatment includes maximal safe surgical resection with combination radiotherapy and adjuvant temozolomide (TMZ) chemotherapy. Alarmingly, patient survival at five-years is below 10%. This is in part due to the invasive behavior of the tumor and the resulting inability to resect greater than 98% of some tumors. In fact, recurrence after such treatment may be inevitable, even in cases where gross total resection is achieved. The Cancer Genome Atlas (TCGA) research network performed whole genome sequencing of GBM tumors and found that GBM recurrence is linked to epigenetic mechanisms and pathways. Central to these pathways are epigenetic enzymes, which have recently emerged as possible new drug targets for multiple cancers, including GBM. Here we review GBM treatment, and provide a systems approach to identifying epigenetic drivers of GBM tumor progression based on temporal modeling of putative GBM cells of origin. We also discuss advances in defining epigenetic mechanisms controlling GBM initiation and recurrence and the drug discovery considerations associated with targeting epigenetic enzymes for GBM treatment.
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Affiliation(s)
- Jennifer Clarke
- Division of Biostatistics; Department of Epidemiology and Public Health; University of Miami Miller School of Medicine; Miami, FL USA
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425
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Mao XG, Song SJ, Xue XY, Yan M, Wang L, Lin W, Guo G, Zhang X. LGR5 is a proneural factor and is regulated by OLIG2 in glioma stem-like cells. Cell Mol Neurobiol 2013; 33:851-65. [PMID: 23793848 DOI: 10.1007/s10571-013-9951-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 06/13/2013] [Indexed: 01/10/2023]
Abstract
The biological functional roles of LGR5 (leucine-rich repeat containing G protein-coupled receptor 5, also known as GPR49), a novel potential marker for stem-like cells in glioblastoma (GSCs), is poorly acknowledged. Here, we demonstrated that LGR5 was detected in glioblastoma tissues and GSCs. Bioinformatics analysis revealed that LGR5 is closely related to neurogenesis and neuronal functions, and preferentially expressed in Proneural subtype of GBMs. Furthermore, LGR5 is regulated by Proneural factor OLIG2, which is important for both neurogenesis and GSC maintenance. Biological experiments in GSC cells validated the bioinformatics analysis results and revealed that LGR5 regulated the tumor sphere formation capacity, an important stem cell property for GSCs. Therefore, LGR5 expression may be functionally correlated with the neurogenic competence, and be regulated by OLIG2 in GSCs.
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Affiliation(s)
- Xing-Gang Mao
- Department of Neurosurgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi Province, China
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426
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Asymmetric cell division of stem and progenitor cells during homeostasis and cancer. Cell Mol Life Sci 2013; 71:575-97. [PMID: 23771628 PMCID: PMC3901929 DOI: 10.1007/s00018-013-1386-1] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 05/21/2013] [Accepted: 05/24/2013] [Indexed: 12/15/2022]
Abstract
Stem and progenitor cells are characterized by their ability to self-renew and produce differentiated progeny. A fine balance between these processes is achieved through controlled asymmetric divisions and is necessary to generate cellular diversity during development and to maintain adult tissue homeostasis. Disruption of this balance may result in premature depletion of the stem/progenitor cell pool, or abnormal growth. In many tissues, including the brain, dysregulated asymmetric divisions are associated with cancer. Whether there is a causal relationship between asymmetric cell division defects and cancer initiation is as yet not known. Here, we review the cellular and molecular mechanisms that regulate asymmetric cell divisions in the neural lineage and discuss the potential connections between this regulatory machinery and cancer.
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427
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Abstract
Glioma and medulloblastoma represent the most commonly occurring malignant brain tumors in adults and in children, respectively. Recent genomic and transcriptional approaches present a complex group of diseases and delineate a number of molecular subgroups within tumors that share a common histopathology. Differences in cells of origin, regional niches, developmental timing, and genetic events all contribute to this heterogeneity. In an attempt to recapitulate the diversity of brain tumors, an increasing array of genetically engineered mouse models (GEMMs) has been developed. These models often utilize promoters and genetic drivers from normal brain development and can provide insight into specific cells from which these tumors originate. GEMMs show promise in both developmental biology and developmental therapeutics. This review describes numerous murine brain tumor models in the context of normal brain development and the potential for these animals to impact brain tumor research.
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Affiliation(s)
- Fredrik J. Swartling
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, SE-75185, Sweden
| | - Sanna-Maria Hede
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, SE-75185, Sweden
| | - William A. Weiss
- University of California, Depts. of Neurology, Pathology, Pediatrics, Neurosurgery, Brain Tumor Research Center and Helen Diller Family Comprehensive Cancer Center, San Francisco CA 94158, USA
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428
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Zhang XQ, Sun S, Lam KF, Kiang KMY, Pu JKS, Ho ASW, Lui WM, Fung CF, Wong TS, Leung GKK. A long non-coding RNA signature in glioblastoma multiforme predicts survival. Neurobiol Dis 2013; 58:123-31. [PMID: 23726844 DOI: 10.1016/j.nbd.2013.05.011] [Citation(s) in RCA: 167] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 05/08/2013] [Accepted: 05/20/2013] [Indexed: 12/19/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) represent the leading edge of cancer research, and have been implicated in cancer biogenesis and prognosis. We aimed to identify lncRNA signatures that have prognostic values in glioblastoma multiforme (GBM). Using a lncRNA-mining approach, we performed lncRNA expression profiling in 213 GBM tumors from The Cancer Genome Atlas (TCGA), randomly divided into a training (n=107) and a testing set (n=106). We analyzed the associations between lncRNA signatures and clinical outcome in the training set, and validated the findings in the testing set. We also validated the identified lncRNA signature in another two independent GBM data sets from Gene Expression Omnibus (GEO), which contained specimens from 68 and 101 patients, respectively. We identified a set of six lncRNAs that were significantly associated with the overall survival in the training set (P≤0.01). Based on this six-lncRNA signature, the training-set patients could be classified into high-risk and low-risk subgroups with significantly different survival (HR=2.13, 95% CI=1.38-3.29; P=0.001). The prognostic value of this six-lncRNA signature was confirmed in the testing set and the two independent data sets. Further analysis revealed that the prognostic value of this signature was independent of age and O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status. The identification of the prognostic lncRNAs indicates the potential roles of lncRNAs in GBM pathogenesis. This six-lncRNA signature may have clinical implications in the subclassification of GBM.
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Affiliation(s)
- Xiao-Qin Zhang
- Department of Surgery, The University of Hong Kong, Hong Kong
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429
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Expansion of oligodendrocyte progenitor cells following SIRT1 inactivation in the adult brain. Nat Cell Biol 2013; 15:614-24. [PMID: 23644469 DOI: 10.1038/ncb2735] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 03/14/2013] [Indexed: 12/13/2022]
Abstract
Oligodendrocytes-the myelin-forming cells of the central nervous system-can be regenerated during adulthood. In adults, new oligodendrocytes originate from oligodendrocyte progenitor cells (OPCs), but also from neural stem cells (NSCs). Although several factors supporting oligodendrocyte production have been characterized, the mechanisms underlying the generation of adult oligodendrocytes are largely unknown. Here we show that genetic inactivation of SIRT1, a protein deacetylase implicated in energy metabolism, increases the production of new OPCs in the adult mouse brain, in part by acting in NSCs. New OPCs produced following SIRT1 inactivation differentiate normally, generating fully myelinating oligodendrocytes. Remarkably, SIRT1 inactivation ameliorates remyelination and delays paralysis in mouse models of demyelinating injuries. SIRT1 inactivation leads to the upregulation of genes involved in cell metabolism and growth factor signalling, in particular PDGF receptor α (PDGFRα). Oligodendrocyte expansion following SIRT1 inactivation is mediated at least in part by AKT and p38 MAPK-signalling molecules downstream of PDGFRα. The identification of drug-targetable enzymes that regulate oligodendrocyte regeneration in adults could facilitate the development of therapies for demyelinating injuries and diseases, such as multiple sclerosis.
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430
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Castelo-Branco G, Bannister AJ. The epigenetics of cancer: from non-coding RNAs to chromatin and beyond. Brief Funct Genomics 2013; 12:161-3. [PMID: 23709460 DOI: 10.1093/bfgp/elt020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Gonçalo Castelo-Branco
- Laboratory of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-17177 Stockholm, Sweden
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431
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The molecular and cell biology of pediatric low-grade gliomas. Oncogene 2013; 33:2019-26. [PMID: 23624918 DOI: 10.1038/onc.2013.148] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 03/05/2013] [Accepted: 03/07/2013] [Indexed: 12/13/2022]
Abstract
Pilocytic astrocytoma (PA) is the most common glial cell tumor arising in children. Sporadic cases are associated with KIAA1549:BRAF fusion rearrangements, while 15-20% of children develop PA in the context of the neurofibromatosis 1 (NF1) inherited tumor predisposition syndrome. The unique predilection of these tumors to form within the optic pathway and brainstem (NF1-PA) and cerebellum (sporadic PA) raises the possibility that gliomagenesis requires more than biallelic inactivation of the NF1 tumor suppressor gene or expression of the KIAA1549:BRAF transcript. Several etiologic explanations include differential susceptibilities of preneoplastic neuroglial cell types in different brain regions to these glioma-causing genetic changes, contributions from non-neoplastic cells and signals in the tumor microenvironment, and genomic modifiers that confer glioma risk. As clinically-faithful rodent models of sporadic PA are currently under development, Nf1 genetically-engineered mouse (GEM) models have served as tractable systems to study the role of the cell of origin, deregulated intracellular signaling, non-neoplastic cells in the tumor microenvironment and genomic modifiers in gliomagenesis. In this report, we highlight advances in Nf1-GEM modeling and review new experimental evidence that supports the emerging concept that Nf1- and KIAA1549:BRAF-induced gliomas arise from specific cell types in particular brain locations.
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432
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Oligodendrocyte progenitors balance growth with self-repulsion to achieve homeostasis in the adult brain. Nat Neurosci 2013; 16:668-76. [PMID: 23624515 PMCID: PMC3807738 DOI: 10.1038/nn.3390] [Citation(s) in RCA: 541] [Impact Index Per Article: 49.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 03/28/2013] [Indexed: 12/14/2022]
Abstract
The adult CNS contains an abundant population of oligodendrocyte precursor cells (NG2+ cells) that generate oligodendrocytes and repair myelin, but how these ubiquitous progenitors maintain their density is unknown. Here we generated NG2-mEGFP mice and used in vivo two-photon imaging to study their dynamics in the adult brain. Time-lapse imaging revealed that NG2+ cells in the cortex are highly dynamic; they survey their local environment with motile filopodia, extend growth cones, and continuously migrate. They maintain unique territories through self-avoidance, and NG2+ cell loss through death, differentiation, or ablation triggered rapid migration and proliferation of adjacent cells to restore their density. NG2+ cells recruited to sites of focal CNS injury were similarly replaced by a proliferative burst surrounding the injury site. Thus, homeostatic control of NG2+ cell density through a balance of active growth and self-repulsion ensures that these progenitors are available to replace oligodendrocytes and participate in tissue repair.
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433
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Barrantes-Freer A, Kim E, Bielanska J, Giese A, Mortensen LS, Schulz-Schaeffer WJ, Stadelmann C, Brück W, Pardo LA. Human glioma-initiating cells show a distinct immature phenotype resembling but not identical to NG2 glia. J Neuropathol Exp Neurol 2013; 72:307-24. [PMID: 23481707 PMCID: PMC3678885 DOI: 10.1097/nen.0b013e31828afdbd] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Glioma-initiating cells (GICs) represent a potential important therapeutic target because they are likely to account for the frequent recurrence of malignant gliomas; however, their identity remains unsolved. Here, we characterized the cellular lineage fingerprint of GICs through a combination of electrophysiology, lineage marker expression, and differentiation assays of 5 human patient-derived primary GIC lines. Most GICs coexpressed nestin, NG2 proteoglycan, platelet-derived growth factor receptor-α, and glial fibrillary acidic protein. Glioma-initiating cells could be partially differentiated into astrocytic but not oligodendroglial or neural lineages. We also demonstrate that GICs have a characteristic electrophysiologic profile distinct from that of well-characterized tumor bulk cells. Together, our results suggest that GICs represent a unique type of cells reminiscent of an immature phenotype that closely resembles but is not identical to NG2 glia with respect to marker expression and functional membrane properties.
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Affiliation(s)
- Alonso Barrantes-Freer
- Max-Planck-Institute of Experimental Medicine, Molecular Biology of Neuronal Signals, AG Oncophysiology, Göttingen
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434
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Hippenmeyer S, Johnson RL, Luo L. Mosaic analysis with double markers reveals cell-type-specific paternal growth dominance. Cell Rep 2013; 3:960-7. [PMID: 23453967 DOI: 10.1016/j.celrep.2013.02.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 01/05/2013] [Accepted: 02/01/2013] [Indexed: 10/27/2022] Open
Abstract
Genomic imprinting leads to preferred expression of either the maternal or paternal alleles of a subset of genes. Imprinting is essential for mammalian development, and its deregulation causes many diseases. However, the functional relevance of imprinting at the cellular level is poorly understood for most imprinted genes. We used mosaic analysis with double markers (MADM) in mice to create uniparental disomies (UPDs) and to visualize imprinting effects with single-cell resolution. Although chromosome 12 UPD did not produce detectable phenotypes, chromosome 7 UPD caused highly significant paternal growth dominance in the liver and lung, but not in the brain or heart. A single gene on chromosome 7, encoding the secreted insulin-like growth factor 2 (IGF2), accounts for most of the paternal dominance effect. Mosaic analyses implied additional imprinted loci on chromosome 7 acting cell autonomously to transmit the IGF2 signal. Our study reveals chromosome- and cell-type specificity of genomic imprinting effects.
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Affiliation(s)
- Simon Hippenmeyer
- Howard Hughes Medical Institute and Department of Biology, Stanford University, Stanford, CA 94305, USA.
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435
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Lee DW, Ramakrishnan D, Valenta J, Parney IF, Bayless KJ, Sitcheran R. The NF-κB RelB protein is an oncogenic driver of mesenchymal glioma. PLoS One 2013; 8:e57489. [PMID: 23451236 PMCID: PMC3581451 DOI: 10.1371/journal.pone.0057489] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 01/22/2013] [Indexed: 12/16/2022] Open
Abstract
High-grade gliomas, such as glioblastomas (GBMs), are very aggressive, invasive brain tumors with low patient survival rates. The recent identification of distinct glioma tumor subtypes offers the potential for understanding disease pathogenesis, responses to treatment and identification of molecular targets for personalized cancer therapies. However, the key alterations that drive tumorigenesis within each subtype are still poorly understood. Although aberrant NF-κB activity has been implicated in glioma, the roles of specific members of this protein family in tumorigenesis and pathogenesis have not been elucidated. In this study, we show that the NF-κB protein RelB is expressed in a particularly aggressive mesenchymal subtype of glioma, and loss of RelB significantly attenuated glioma cell survival, motility and invasion. We find that RelB promotes the expression of mesenchymal genes including YKL-40, a marker of the MES glioma subtype. Additionally, RelB regulates expression of Olig2, a regulator of cancer stem cell proliferation and a candidate marker for the cell of origin in glioma. Furthermore, loss of RelB in glioma cells significantly diminished tumor growth in orthotopic mouse xenografts. The relevance of our studies for human disease was confirmed by analysis of a human GBM genome database, which revealed that high RelB expression strongly correlates with rapid tumor progression and poor patient survival rates. Thus, our findings demonstrate that RelB is an oncogenic driver of mesenchymal glioma tumor growth and invasion, highlighting the therapeutic potential of inhibiting the noncanonical NF-κB (RelB-mediated) pathway to treat these deadly tumors.
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Affiliation(s)
- Dong Whan Lee
- Department of Molecular & Cellular Medicine, Texas A&M University Health Science Center, College Station, Texas, United States of America
| | - Dhivya Ramakrishnan
- Department of Molecular & Cellular Medicine, Texas A&M University Health Science Center, College Station, Texas, United States of America
| | - John Valenta
- Department of Molecular & Cellular Medicine, Texas A&M University Health Science Center, College Station, Texas, United States of America
| | - Ian F. Parney
- Department of Neurologic Surgery, Mayo Clinic Cancer Center, Rochester, Minnesota, United States of America
| | - Kayla J. Bayless
- Department of Molecular & Cellular Medicine, Texas A&M University Health Science Center, College Station, Texas, United States of America
| | - Raquel Sitcheran
- Department of Molecular & Cellular Medicine, Texas A&M University Health Science Center, College Station, Texas, United States of America
- * E-mail:
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436
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Galvão RP, Zong H. Inflammation and Gliomagenesis: Bi-Directional Communication at Early and Late Stages of Tumor Progression. CURRENT PATHOBIOLOGY REPORTS 2013; 1:19-28. [PMID: 23538742 DOI: 10.1007/s40139-012-0006-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Inflammation has been closely linked to various forms of cancer. Less is known about the role of inflammation in glioma, especially at the initiation stage. In this review, we first describe the unique features of the immune system in the brain. We then discuss the current understanding of the mechanisms by which glioma cells modulate the immune system, especially how bi-directional communications between immune cells and glioma cells create an immunosuppressed microenvironment that promotes tumor survival and growth. We also address the potential tumor-initiating roles of inflammation in glioma. Finally, we describe several immunotherapy approaches currently being developed to reverse these interactions and stimulate the immune system to eliminate glioma cells.
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Affiliation(s)
- Rui Pedro Galvão
- Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
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437
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Bartesaghi S, Salomoni P. Tumor suppressive pathways in the control of neurogenesis. Cell Mol Life Sci 2013; 70:581-97. [PMID: 22802124 PMCID: PMC11113109 DOI: 10.1007/s00018-012-1063-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 06/16/2012] [Accepted: 06/18/2012] [Indexed: 12/16/2022]
Abstract
The generation of specialized neural cells in the developing and postnatal central nervous system is a highly regulated process, whereby neural stem cells divide to generate committed neuronal progenitors, which then withdraw from the cell cycle and start to differentiate. Cell cycle checkpoints play a major role in regulating the balance between neural stem cell expansion and differentiation. Loss of tumor suppressors involved in checkpoint control can lead to dramatic alterations of neurogenesis, thus contributing to neoplastic transformation. Here we summarize and critically discuss the existing literature on the role of tumor suppressive pathways and their regulatory networks in the control of neurogenesis and transformation.
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Affiliation(s)
- Stefano Bartesaghi
- Samantha Dickson Brain Cancer Unit, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD UK
| | - Paolo Salomoni
- Samantha Dickson Brain Cancer Unit, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD UK
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438
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Swartling FJ, Bolin S, Phillips JJ, Persson AI. Signals that regulate the oncogenic fate of neural stem cells and progenitors. Exp Neurol 2013; 260:56-68. [PMID: 23376224 DOI: 10.1016/j.expneurol.2013.01.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 01/19/2013] [Accepted: 01/24/2013] [Indexed: 12/16/2022]
Abstract
Brain tumors have frequently been associated with a neural stem cell (NSC) origin and contain stem-like tumor cells, so-called brain tumor stem cells (BTSCs) that share many features with normal NSCs. A stem cell state of BTSCs confers resistance to radiotherapy and treatment with alkylating agents. It is also a hallmark of aggressive brain tumors and is maintained by transcriptional networks that are also active in embryonic stem cells. Advances in reprogramming of somatic cells into induced pluripotent stem (iPS) cells have further identified genes that drive stemness. In this review, we will highlight the possible drivers of stemness in medulloblastoma and glioma, the most frequent types of primary malignant brain cancer in children and adults, respectively. Signals that drive expansion of developmentally defined neural precursor cells are also active in corresponding brain tumors. Transcriptomal subgroups of human medulloblastoma and glioma match features of NSCs but also more restricted progenitors. Lessons from genetically-engineered mouse (GEM) models show that temporally and regionally defined NSCs can give rise to distinct subgroups of medulloblastoma and glioma. We will further discuss how acquisition of stem cell features may drive brain tumorigenesis from a non-NSC origin. Genetic alterations, signaling pathways, and therapy-induced changes in the tumor microenvironment can drive reprogramming networks and induce stemness in brain tumors. Finally, we propose a model where dysregulation of microRNAs (miRNAs) that normally provide barriers against reprogramming plays an integral role in promoting stemness in brain tumors.
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Affiliation(s)
- Fredrik J Swartling
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Sara Bolin
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Joanna J Phillips
- Department of Neurological Surgery, Brain Tumor Research Center, University of California, San Francisco, USA; Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, USA
| | - Anders I Persson
- Department of Neurological Surgery, Brain Tumor Research Center, University of California, San Francisco, USA; Department of Neurology, Sandler Neurosciences Center, University of California, San Francisco, USA.
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439
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Solga AC, Gianino SM, Gutmann DH. NG2-cells are not the cell of origin for murine neurofibromatosis-1 (Nf1) optic glioma. Oncogene 2013; 33:289-99. [PMID: 23318450 DOI: 10.1038/onc.2012.580] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 10/26/2012] [Accepted: 10/26/2012] [Indexed: 01/19/2023]
Abstract
Low-grade glial neoplasms (astrocytomas) represent one of the most common brain tumors in the pediatric population. These tumors frequently form in the optic pathway (optic pathway gliomas, OPGs), especially in children with the neurofibromatosis type 1 (NF1)-inherited tumor predisposition syndrome. To model these tumors in mice, we have previously developed several Nf1 genetically-engineered mouse strains that form optic gliomas. However, there are three distinct macroglial cell populations in the optic nerve (astrocytes, NG2+ (nerve/glial antigen 2) cells and oligodendrocytes). The presence of NG2+ cells in the optic nerve raises the intriguing possibility that these cells could be the tumor-initiating cells, as has been suggested for adult glioma. In this report, we used a combination of complementary in vitro and novel genetically-engineered mouse strains in vivo to determine whether NG2+ cells could give rise to Nf1 optic glioma. First, we show that Nf1 inactivation results in a cell-autonomous increase in glial fibrillary acidic protein+ (GFAP+), but not in NG2+, cell proliferation in vitro. Second, similar to the GFAP-Cre transgenic strain that drives Nf1 optic gliomagenesis, NG2-expressing cells also give rise to all three macroglial lineages in vivo. Third, in contrast to the GFAP-Cre strain, Nf1 gene inactivation in NG2+ cells is not sufficient for optic gliomagenesis in vivo. Collectively, these data demonstrate that NG2+ cells are not the cell of origin for mouse optic glioma, and support a model in which gliomagenesis requires Nf1 loss in specific neuroglial progenitors during embryogenesis.
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Affiliation(s)
- A C Solga
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - S M Gianino
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
| | - D H Gutmann
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA
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440
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Kondo T. Molecular markers of glioma initiating cells. Inflamm Regen 2013. [DOI: 10.2492/inflammregen.33.181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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441
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Abstract
Glioma is a heterogeneous disease process with differential histology and treatment response. It was previously thought that the histological features of glial tumors indicated their cell of origin. However, the discovery of continuous neuro-gliogenesis in the normal adult brain and the identification of brain tumor stem cells within glioma have led to the hypothesis that these brain tumors originate from multipotent neural stem or progenitor cells, which primarily divide asymmetrically during the postnatal period. Asymmetric cell division allows these cell types to concurrently self-renew whilst also producing cells for the differentiation pathway. It has recently been shown that increased symmetrical cell division, favoring the self-renewal pathway, leads to oligodendroglioma formation from oligodendrocyte progenitor cells. In contrast, there is some evidence that asymmetric cell division maintenance in tumor stem-like cells within astrocytoma may lead to acquisition of treatment resistance. Therefore cell division mode in normal brain stem and progenitor cells may play a role in setting tumorigenic potential and the type of tumor formed. Moreover, heterogeneous tumor cell populations and their respective cell division mode may confer differential sensitivity to therapy. This review aims to shed light on the controllers of cell division mode which may be therapeutically targeted to prevent glioma formation and improve treatment response.
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442
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Tabu K, Bizen N, Taga T, Tanaka S. Gene Regulation of Prominin-1 (CD133) in Normal and Cancerous Tissues. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 777:73-85. [PMID: 23161076 DOI: 10.1007/978-1-4614-5894-4_5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A pentaspan membrane glycoprotein prominin-1 (frequently called CD133 in human) is widely used as a surface marker to identify and isolate normal stem/progenitor cells from various organs, although it is also expressed in some types of differentiated cells. Since CD133 was identified as a universal marker to isolate cancer stem cells (CSCs) in tumors derived from multiple tissues, much attention has been directed toward the relationship between its gene regulation and identity of CSCs (i.e., cancer stemness). Prominin-1 (PROM1) gene possesses five alternative promoters yielding multiple first exons within the 5'-untranslated region (UTR) and also splicing variants affecting the open reading frame (ORF) sequence, implicating the complicated gene regulation in a context-dependent manner. This chapter aims to organize the accumulated findings on prominin-1 with a focus on its altered expression and regulation in normal and cancerous cells and to discuss potential regulatory networks underlying cancer stemness.
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Affiliation(s)
- Kouichi Tabu
- Department of Stem cell Regulation, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, 113-8510, Tokyo, Japan,
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443
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Purinergic signaling in glioma progression. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 986:81-102. [PMID: 22879065 DOI: 10.1007/978-94-007-4719-7_5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Among the pathological alterations that give tumor cells invasive potential, purinergic signaling is emerging as an important component. Studies performed in in vitro, in vivo and ex vivo glioma models indicate that alterations in the purinergic signaling are involved in the progression of these tumors. Gliomas have low expression of all E-NTPDases, when compared to astrocytes in culture. Nucleotides induce glioma proliferation and ATP, although potentially neurotoxic, does not evoke cytotoxic action on the majority of glioma cells in culture. The importance of extracellular ATP for glioma pathobiology was confirmed by the reduction in glioma tumor size by apyrase, which degrades extracellular ATP to AMP, and the striking increase in tumor size by over-expression of an ecto-enzyme that degrades ATP to ADP, suggesting the effect of extracellular ATP on the tumor growth depends on the nucleotide produced by its degradation. The participation of purinergic receptors on glioma progression, particularly P2X(7), is involved in the resistance to ATP-induced cell death. Although more studies are necessary, the purinergic signaling, including ectonucleotidases and receptors, may be considered as future target for glioma pharmacological or gene therapy.
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444
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Affiliation(s)
- Andrei V Krivtsov
- Human Oncology and Pathogenesis Program and Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
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445
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Gubanova NV, Gaytan AS, Razumov IA, Mordvinov VA, Krivoshapkin AL, Netesov SV, Chumakov PM. Oncolytic viruses in the therapy of gliomas. Mol Biol 2012. [DOI: 10.1134/s0026893312060064] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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446
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Kaul A, Chen YH, Emnett RJ, Dahiya S, Gutmann DH. Pediatric glioma-associated KIAA1549:BRAF expression regulates neuroglial cell growth in a cell type-specific and mTOR-dependent manner. Genes Dev 2012; 26:2561-6. [PMID: 23152448 DOI: 10.1101/gad.200907.112] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Tandem duplications involving the BRAF kinase gene have recently been identified as the most frequent genetic alteration in sporadic pediatric glioma, creating a novel fusion protein (f-BRAF) with increased BRAF activity. To define the role of f-BRAF in gliomagenesis, we demonstrate that f-BRAF regulates neural stem cell (NSC), but not astrocyte, proliferation and is sufficient to induce glioma-like lesions in mice. Moreover, f-BRAF-driven NSC proliferation results from tuberin/Rheb-mediated mammalian target of rapamycin (mTOR) hyperactivation, leading to S6-kinase-dependent degradation of p27. Collectively, these results establish mTOR pathway activation as a key growth regulatory mechanism common to both sporadic and familial low-grade gliomas in children.
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Affiliation(s)
- Aparna Kaul
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63108, USA
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447
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Zhu Y, Liu S, Yin Q, Xu T, Wu X, Zhuang Y. Generation of Dhx9-deficient clones in T-cell development with a mitotic recombination technique. Genesis 2012; 50:543-51. [PMID: 22988576 DOI: 10.1002/dvg.22005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Mitotic recombination is an effective tool for generating mutant clones in somatic tissues. Because of difficulties associated with detecting and quantifying mutant clones in mice, this technique is limited to analysis of growth-related phenotypes induced by loss function of tumor suppressor genes. Here, we used the polymorphic CD45.1/CD45.2 alleles on chromosome 1 as pan-hematopoietic markers to track mosaic clones generated through mitotic recombination in developing T cells. We show that lineage-specific mitotic recombination can be induced and reliably detected as CD45.1 or CD45.2 homozygous clones from the CD45.1/CD45.2 heterozygous background. We have applied this system in the analysis of a lethal mutation in the Dhx9 gene. Mosaic analysis revealed a stage-specific role for Dhx9 during T-cell maturation. Thus, the experimental system described in this study offers a practical means for mosaic analysis of germline mutations in the hematopoietic system.
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Affiliation(s)
- Yi Zhu
- Institute of Developmental Biology and Molecular Medicine, School of Life Science, Fudan University, Shanghai, China
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448
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Friedmann-Morvinski D, Bushong EA, Ke E, Soda Y, Marumoto T, Singer O, Ellisman MH, Verma IM. Dedifferentiation of neurons and astrocytes by oncogenes can induce gliomas in mice. Science 2012; 338:1080-4. [PMID: 23087000 DOI: 10.1126/science.1226929] [Citation(s) in RCA: 406] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Glioblastoma multiforme (GBM) is the most common and aggressive malignant primary brain tumor in humans. Here we show that gliomas can originate from differentiated cells in the central nervous system (CNS), including cortical neurons. Transduction by oncogenic lentiviral vectors of neural stem cells (NSCs), astrocytes, or even mature neurons in the brains of mice can give rise to malignant gliomas. All the tumors, irrespective of the site of lentiviral vector injection (the initiating population), shared common features of high expression of stem or progenitor markers and low expression of differentiation markers. Microarray analysis revealed that tumors of astrocytic and neuronal origin match the mesenchymal GBM subtype. We propose that most differentiated cells in the CNS upon defined genetic alterations undergo dedifferentiation to generate a NSC or progenitor state to initiate and maintain the tumor progression, as well as to give rise to the heterogeneous populations observed in malignant gliomas.
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Transposon mutagenesis identifies genes that transform neural stem cells into glioma-initiating cells. Proc Natl Acad Sci U S A 2012; 109:E2998-3007. [PMID: 23045694 DOI: 10.1073/pnas.1215899109] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Neural stem cells (NSCs) are considered to be the cell of origin of glioblastoma multiforme (GBM). However, the genetic alterations that transform NSCs into glioma-initiating cells remain elusive. Using a unique transposon mutagenesis strategy that mutagenizes NSCs in culture, followed by additional rounds of mutagenesis to generate tumors in vivo, we have identified genes and signaling pathways that can transform NSCs into glioma-initiating cells. Mobilization of Sleeping Beauty transposons in NSCs induced the immortalization of astroglial-like cells, which were then able to generate tumors with characteristics of the mesenchymal subtype of GBM on transplantation, consistent with a potential astroglial origin for mesenchymal GBM. Sequence analysis of transposon insertion sites from tumors and immortalized cells identified more than 200 frequently mutated genes, including human GBM-associated genes, such as Met and Nf1, and made it possible to discriminate between genes that function during astroglial immortalization vs. later stages of tumor development. We also functionally validated five GBM candidate genes using a previously undescribed high-throughput method. Finally, we show that even clonally related tumors derived from the same immortalized line have acquired distinct combinations of genetic alterations during tumor development, suggesting that tumor formation in this model system involves competition among genetically variant cells, which is similar to the Darwinian evolutionary processes now thought to generate many human cancers. This mutagenesis strategy is faster and simpler than conventional transposon screens and can potentially be applied to any tissue stem/progenitor cells that can be grown and differentiated in vitro.
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Shibata M, Shen MM. The roots of cancer: stem cells and the basis for tumor heterogeneity. Bioessays 2012; 35:253-60. [PMID: 23027425 DOI: 10.1002/bies.201200101] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recent studies of prostate cancer and other tumor types have revealed significant support, as well as unexpected complexities, for the application of concepts from normal stem cell biology to cancer. In particular, the cell of origin and cancer stem cell models have been proposed to explain the heterogeneity of tumors during the initiation, propagation, and evolution of cancer. Thus, a basis of intertumor heterogeneity has emerged from studies investigating whether stem cells and/or non-stem cells can serve as cells of origin for cancer and give rise to tumor subtypes that vary in disease outcome. Furthermore, analyses of putative cancer stem cells have revealed the genetically diverse nature of cancers and expanded our understanding of intratumor heterogeneity and clonal evolution. Overall, the principles that have emerged from these stem cell studies highlight the challenges to be surmounted to develop effective treatment strategies for cancer.
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Affiliation(s)
- Maho Shibata
- Department of Medicine, Herbert Irving Comprehensive Cancer Center, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
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