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Namiot ED, Zembatov GM, Tregub PP. Insights into brain tumor diagnosis: exploring in situ hybridization techniques. Front Neurol 2024; 15:1393572. [PMID: 39022728 PMCID: PMC11252041 DOI: 10.3389/fneur.2024.1393572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 05/31/2024] [Indexed: 07/20/2024] Open
Abstract
Objectives Diagnosing brain tumors is critical due to their complex nature. This review explores the potential of in situ hybridization for diagnosing brain neoplasms, examining their attributes and applications in neurology and oncology. Methods The review surveys literature and cross-references findings with the OMIM database, examining 513 records. It pinpoints mutations suitable for in situ hybridization and identifies common chromosomal and gene anomalies in brain tumors. Emphasis is placed on mutations' clinical implications, including prognosis and drug sensitivity. Results Amplifications in EGFR, MDM2, and MDM4, along with Y chromosome loss, chromosome 7 polysomy, and deletions of PTEN, CDKN2/p16, TP53, and DMBT1, correlate with poor prognosis in glioma patients. Protective genetic changes in glioma include increased expression of ADGRB3/1, IL12B, DYRKA1, VEGFC, LRRC4, and BMP4. Elevated MMP24 expression worsens prognosis in glioma, oligodendroglioma, and meningioma patients. Meningioma exhibits common chromosomal anomalies like loss of chromosomes 1, 9, 17, and 22, with specific genes implicated in their development. Main occurrences in medulloblastoma include the formation of isochromosome 17q and SHH signaling pathway disruption. Increased expression of BARHL1 is associated with prolonged survival. Adenomas mutations were reviewed with a focus on adenoma-carcinoma transition and different subtypes, with MMP9 identified as the main metalloprotease implicated in tumor progression. Discussion Molecular-genetic diagnostics for common brain tumors involve diverse genetic anomalies. In situ hybridization shows promise for diagnosing and prognosticating tumors. Detecting tumor-specific alterations is vital for prognosis and treatment. However, many mutations require other methods, hindering in situ hybridization from becoming the primary diagnostic method.
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Affiliation(s)
- E. D. Namiot
- Department of Pathophysiology, First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - G. M. Zembatov
- Department of Pathophysiology, First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - P. P. Tregub
- Department of Pathophysiology, First Moscow State Medical University (Sechenov University), Moscow, Russia
- Brain Research Department, Federal State Scientific Center of Neurology, Moscow, Russia
- Scientific and Educational Resource Center, Innovative Technologies of Immunophenotyping, Digital Spatial Profiling and Ultrastructural Analysis, Peoples' Friendship University of Russia (RUDN University), Moscow, Russia
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Abstract
As a cancer predisposition syndrome, individuals with neurofibromatosis type 1 (NF1) are at increased risk for the development of both benign and malignant tumors. One of the most common locations for these cancers is the central nervous system, where low-grade gliomas predominate in children. During early childhood, gliomas affecting the optic pathway are most frequently encountered, whereas gliomas of the brainstem and other locations are observed in slightly older children. In contrast, the majority of gliomas arising in adults with NF1 are malignant cancers, typically glioblastoma, involving the cerebral hemispheres. Our understanding of the pathogenesis of NF1-associated gliomas has been significantly advanced through the use of genetically engineered mice, yielding new targets for therapeutic drug design and evaluation. In addition, Nf1 murine glioma models have served as instructive platforms for defining the cell of origin of these tumors, elucidating the critical role of the tumor microenvironment in determining tumor growth and vision loss, and determining how cancer risk factors (sex, germline NF1 mutation) impact on glioma formation and progression. Moreover, these preclinical models have permitted early phase analysis of promising drugs that reduce tumor growth and attenuate vision loss, as an initial step prior to translation to human clinical trials.
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Affiliation(s)
| | - David H Gutmann
- Department of Neurology, Washington University School of Medicine, St. Louis, MO
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Das A, Ghosh P, Zameer L, Ramprasad VL, Bhaduri A. Simultaneous diagnosis of unilateral retinoblastoma and contralateral optic pathway glioma in a child with neurofibromatosis type 1. Pediatr Hematol Oncol 2019; 36:82-85. [PMID: 30963792 DOI: 10.1080/08880018.2019.1591550] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Anirban Das
- a Department of Pediatric Hematology/Oncology , Tata Medical Center , Kolkata , India
| | - Priya Ghosh
- b Department of Radiology , Tata Medical Center , Kolkata , India
| | - Lateef Zameer
- c Department of Histopathology , Tata Medical Center , Kolkata , India
| | | | - Anirban Bhaduri
- e Department of Ophthalmology , The Calcutta Medical Research Institute , Kolkata , India
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Conventional and advanced MRI features of pediatric intracranial tumors: posterior fossa and suprasellar tumors. AJR Am J Roentgenol 2013; 200:1115-24. [PMID: 23617498 DOI: 10.2214/ajr.12.9725] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE In this article, we review the most common posterior fossa and suprasellar intracranial neoplasms in the pediatric population. We briefly discuss basic MRI concepts used in the initial evaluation of a pediatric brain tumor and then discuss sophisticated MRI techniques that give insight into the physiology and chemical makeup of these tumors to help the radiologist make a more specific diagnosis. CONCLUSION Diagnosis and treatment of pediatric CNS tumors necessitate a multi-disciplinary approach and require expertise and diligence of all parties involved. Imaging is an essential component has evolved greatly over the past decade. We are becoming better at making a preoperative diagnosis of that tumor type, detecting recurrence, and guiding surgical management to avoid injury to vital brain structures.
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Gutmann DH, McLellan MD, Hussain I, Wallis JW, Fulton LL, Fulton RS, Magrini V, Demeter R, Wylie T, Kandoth C, Leonard JR, Guha A, Miller CA, Ding L, Mardis ER. Somatic neurofibromatosis type 1 (NF1) inactivation characterizes NF1-associated pilocytic astrocytoma. Genome Res 2012; 23:431-9. [PMID: 23222849 PMCID: PMC3589532 DOI: 10.1101/gr.142604.112] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Low-grade brain tumors (pilocytic astrocytomas) arising in the neurofibromatosis type 1 (NF1) inherited cancer predisposition syndrome are hypothesized to result from a combination of germline and acquired somatic NF1 tumor suppressor gene mutations. However, genetically engineered mice (GEM) in which mono-allelic germline Nf1 gene loss is coupled with bi-allelic somatic (glial progenitor cell) Nf1 gene inactivation develop brain tumors that do not fully recapitulate the neuropathological features of the human condition. These observations raise the intriguing possibility that, while loss of neurofibromin function is necessary for NF1-associated low-grade astrocytoma development, additional genetic changes may be required for full penetrance of the human brain tumor phenotype. To identify these potential cooperating genetic mutations, we performed whole-genome sequencing (WGS) analysis of three NF1-associated pilocytic astrocytoma (PA) tumors. We found that the mechanism of somatic NF1 loss was different in each tumor (frameshift mutation, loss of heterozygosity, and methylation). In addition, tumor purity analysis revealed that these tumors had a high proportion of stromal cells, such that only 50%–60% of cells in the tumor mass exhibited somatic NF1 loss. Importantly, we identified no additional recurrent pathogenic somatic mutations, supporting a model in which neuroglial progenitor cell NF1 loss is likely sufficient for PA formation in cooperation with a proper stromal environment.
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Affiliation(s)
- David H Gutmann
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Pascual-Castroviejo I, Pascual-Pascual SI. Neurofibromatosis type 1 (NF1) associated with tumor of the corpus callosum. Childs Nerv Syst 2012; 28:2177-80. [PMID: 23001021 DOI: 10.1007/s00381-012-1903-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 08/25/2012] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Neurofibromatosis type 1 (NF1), one of the most common neurocutaneous disorders, is a multisystemic disease associated with tumors in any organ of the body, especially in the central nervous system and also the peripheral nervous system. Pilocytic astrocytomas have been described in almost all intracranial regions in patients with NF1. However, only a few patients with NF1 and tumor of the corpus callosum have been reported to date. MATERIAL AND METHODS An 11-year-old white Spanish boy was evaluated due to a family history of NF1 and low performance test scores in school. He was studied from the neurological and intellectual level points of view. RESULTS Magnetic resonance (MR) study revealed a tumor in the anterior-middle portion of the corpus callosum and a Wechsler Intelligence Scale for Children-Revised showed verbal IQ of 92, a performance IQ of 108, and a total IQ of 100. In addition, he showed attention deficit and hyperactivity disorder. CONCLUSIONS Tumors of corpus callosum in patients with NF1 are very uncommon. The patient presented in this paper consulted due to family history of NF1, progressive hyperactivity, and below average school performance. The MR study showed tumor in the corpus callosum. Tumor histology was not investigated.
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Gilheeney SW, Kieran MW. Differences in molecular genetics between pediatric and adult malignant astrocytomas: age matters. Future Oncol 2012; 8:549-58. [PMID: 22646770 DOI: 10.2217/fon.12.51] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The microscope - the classical tool for the investigation of cells and tissues - remains the basis for the classification of tumors throughout the body. Nowhere has this been more true than in the grading of astrocytomas. In spite of the fact that our parents warned us not to judge a book by its cover, we have continued to assume that adult and pediatric malignant gliomas that look the same, will have the same mutations, and thus respond to the same therapy. Rapid advances in molecular biology have permitted us the opportunity to go inside the cell and characterize the genetic events that underlie the true molecular heterogeneity of adult and pediatric brain tumors. In this paper, we will discuss some of the important clinical differences between pediatric and adult gliomas, with a focus on the molecular analysis of these different age groups.
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Affiliation(s)
- Stephen W Gilheeney
- Pediatric Neuro-Oncology, Dana-Farber Children's Hospital Cancer Center, Boston, MA, USA.
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Abstract
PURPOSE The aim is to describe the behavior of pilocytic astrocytoma (PAs) and its effects on patient prognosis by using flow cytometric, immunohistochemical and cytogenetic methods. We also aim to find out whether there is any difference between differently localized tumors by the above mentioned analyses. METHODS We studied DNA index, expression of p53, p16, pRb, MMAC/PTEN1, VEGF, MIB-1 index and chromosomal anomalies which can be detected by array comparative genomic hybridization (CGH) technique. We analyzed the association of the results of these studies with clinical prognosis and tumor localization. We included 53 patients (18 cerebellar, 20 chiasmatic/hypothalamic and 15 hemispheric). Samples were studied from paraffin embedded tumors. RESULTS We found that PAs are mostly diploid and ploidy pattern does not affect the prognosis. The expression of p53, p16, pRb, MMAC/PTEN1 and VEGF was not significantly different between different localizations and could not predict the prognosis. Frequently seen copy number aberrations (CNAs) are: amplification in 1p36.33, 2p11.2, 9p11.2, 9q12, 16p11.2, 19q13.12-q13.2, Xp22.2-p21.3, Xp11.3-p11.22, Xq11.1-q12, Xq13.1, Xq21.1-q21.31, Xq22.3, Xq26.3 and homozygous deletion in 2p11.2, 8p23.1, 16p12.3. Among them, 2p11.2 amp, 9p11.2 amp and 1p36.21 hom del were correlated with prognosis. Moreover, we found a significant correlation between 16p11.2 amp and tumor localization. CONCLUSIONS Differently localized PAs have different properties which make them behave with different biological aggressiveness. PAs demonstrate a significant amount of CNAs that can be detected by a high-resolution study. However, tumor suppressor genes p53, p16, pRb, MMAC/PTEN1 and expression patterns do not play a significant role in PAs.
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Crouse NR, Dahiya S, Gutmann DH. Rethinking Pediatric Gliomas as Developmental Brain Abnormalities. Curr Top Dev Biol 2011; 94:283-308. [DOI: 10.1016/b978-0-12-380916-2.00009-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Pascual-Castroviejo I, Pascual-Pascual SI, Viaño J, Carceller F, Gutierrez-Molina M, Morales C, Frutos-Martinez R. Posterior fossa tumors in children with neurofibromatosis type 1 (NF1). Childs Nerv Syst 2010; 26:1599-603. [PMID: 20464401 DOI: 10.1007/s00381-010-1163-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Accepted: 04/22/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND Tumours of the posterior fossa associated with neurofibromatosis type 1 (NF1) are very infrequent. Series studying this association are seldom reported. PERSONAL EXPERIENCE In a series of 600 NF1 patients studied during 39 years (1965-2004) only five (0.83%) had posterior fossa tumours. They were studied clinically, radiologically by computerized tomography (CT) or magnetic resonance (MR) and histologically. Four of them had astrocytomas but only in one case was the tumour primarily cerebellar while the tumour was primarily of the brain stem with invasion of the adjacent regions of one or both cerebellar hemispheres in three patients. The fifth tumour was a medulloblastoma that had a survival of 3 years following treatment. The patient with primary cerebellar astrocytoma is apparently cured 7 years after the removal of the tumour. The patients with the brain stem tumours extending to the cerebellum, showed a chronic slowly progressive cerebellar disease, but remain alive at age of more than 20 years (one was lost to follow-up). DISCUSSION AND CONCLUSION The aim of this study was to present five children (one male and four females) less than 16 years of age when they were initially seen in our service, who had NF1 associates with posterior fossa tumours. This location is very uncommon in patients with NF1, in contrast with those located in other regions, such as pathway optic tumours and brain stem tumours. Most of these tumours are histologically benign (low grade astrocytomas). Only one patient in this series had a medulloblastoma, an exceptionally rare tumour seldom reported in patients with NF1.
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Lee JS, Padmanabhan A, Shin J, Zhu S, Guo F, Kanki JP, Epstein JA, Look AT. Oligodendrocyte progenitor cell numbers and migration are regulated by the zebrafish orthologs of the NF1 tumor suppressor gene. Hum Mol Genet 2010; 19:4643-53. [PMID: 20858602 DOI: 10.1093/hmg/ddq395] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Neurofibromatosis type 1 is the most commonly inherited human cancer predisposition syndrome. Neurofibromin (NF1) gene mutations lead to increased risk of neurofibromas, schwannomas, low grade, pilocytic optic pathway gliomas, as well as malignant peripheral nerve sheath tumors and glioblastomas. Despite the evidence for NF1 tumor suppressor function in glial cell tumors, the mechanisms underlying transformation remain poorly understood. In this report, we used morpholinos to knockdown the two nf1 orthologs in zebrafish and show that oligodendrocyte progenitor cell (OPC) numbers are increased in the developing spinal cord, whereas neurons are unaffected. The increased OPC numbers in nf1 morphants resulted from increased proliferation, as detected by increased BrdU labeling, whereas TUNEL staining for apoptotic cells was unaffected. This phenotype could be rescued by the forced expression of the GTPase-activating protein (GAP)-related domain of human NF1. In addition, the in vivo analysis of OPC migration following nf1 loss using time-lapse microscopy demonstrated that olig2-EGFP(+) OPCs exhibit enhanced cell migration within the developing spinal cord. OPCs pause intermittently as they migrate, and in nf1 knockdown animals, they covered greater distances due to a decrease in average pause duration, rather than an increase in velocity while in motion. Interestingly, nf1 knockdown also leads to an increase in ERK signaling, principally in the neurons of the spinal cord. Together, these results show that negative regulation of the Ras pathway through the GAP activity of NF1 limits OPC proliferation and motility during development, providing insight into the oncogenic mechanisms through which NF1 loss contributes to human glial tumors.
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Affiliation(s)
- Jeong-Soo Lee
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, 44 Binney Street, Boston, MA 02115, USA
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Tihan T, Bloomer MM. Astrocytic neoplasms of the central nervous system and orbit: a morphologic perspective. Semin Diagn Pathol 2010; 27:114-21. [DOI: 10.1053/j.semdp.2010.04.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Somatic mitochondrial mutations in pilocytic astrocytoma. ACTA ACUST UNITED AC 2009; 192:30-5. [DOI: 10.1016/j.cancergencyto.2009.03.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2009] [Revised: 03/03/2009] [Accepted: 03/04/2009] [Indexed: 01/15/2023]
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Brems H, Beert E, de Ravel T, Legius E. Mechanisms in the pathogenesis of malignant tumours in neurofibromatosis type 1. Lancet Oncol 2009; 10:508-15. [PMID: 19410195 DOI: 10.1016/s1470-2045(09)70033-6] [Citation(s) in RCA: 226] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Neurofibromatosis type 1 (NF1) is a familial tumour syndrome. Malignant tumours can arise in the nervous and non-nervous system in either childhood or adulthood, with malignant peripheral nerve sheath tumours being most common. Rhabdomyosarcoma and neuroblastoma are paediatric neoplasms that are more common in children with NF1 than in those without the syndrome. Gastrointestinal stromal tumours, somatostatinomas, breast cancer, and phaeochromocytomas are seen in adults with NF1. Several pathways are thought to be involved in the development of tumours associated with NF1: rat sarcoma viral oncogene homologue (RAS)-mitogen activated protein kinase (MAPK), mammalian target of rapamycin (mTOR), and P21 protein (Cdc42/Rac)-activated kinase 1 (PAK1). New insights into the pathogenesis of these tumours will lead to a better understanding of tumour origin and development and will hopefully allow the discovery of new and specific treatments.
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Affiliation(s)
- Hilde Brems
- Department of Human Genetics, Catholic University Leuven, Leuven, Belgium
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di Tomaso E, London N, Fuja D, Logie J, Tyrrell JA, Kamoun W, Munn LL, Jain RK. PDGF-C induces maturation of blood vessels in a model of glioblastoma and attenuates the response to anti-VEGF treatment. PLoS One 2009; 4:e5123. [PMID: 19352490 PMCID: PMC2662415 DOI: 10.1371/journal.pone.0005123] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Accepted: 02/23/2009] [Indexed: 01/06/2023] Open
Abstract
Background Recent clinical trials of VEGF inhibitors have shown promise in the treatment of recurrent glioblastomas (GBM). However, the survival benefit is usually short-lived as tumors escape anti-VEGF therapies. Here we tested the hypothesis that Platelet Derived Growth Factor-C (PDGF-C), an isoform of the PDGF family, affects GBM progression independent of VEGF pathway and hinders anti-VEGF therapy. Principal Findings We first showed that PDGF-C is present in human GBMs. Then, we overexpressed or downregulated PDGF-C in a human GBM cell line, U87MG, and grew them in cranial windows in nude mice to assess vessel structure and function using intravital microscopy. PDGF-C overexpressing tumors had smaller vessel diameters and lower vascular permeability compared to the parental or siRNA-transfected tumors. Furthermore, vessels in PDGF-C overexpressing tumors had more extensive coverage with NG2 positive perivascular cells and a thicker collagen IV basement membrane than the controls. Treatment with DC101, an anti-VEGFR-2 antibody, induced decreases in vessel density in the parental tumors, but had no effect on the PDGF-C overexpressing tumors. Conclusion These results suggest that PDGF-C plays an important role in glioma vessel maturation and stabilization, and that it can attenuate the response to anti-VEGF therapy, potentially contributing to escape from vascular normalization.
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Affiliation(s)
- Emmanuelle di Tomaso
- E.L. Steele Laboratory for Tumor Biology, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Nyall London
- E.L. Steele Laboratory for Tumor Biology, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Daniel Fuja
- E.L. Steele Laboratory for Tumor Biology, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - James Logie
- E.L. Steele Laboratory for Tumor Biology, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - James A. Tyrrell
- E.L. Steele Laboratory for Tumor Biology, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Walid Kamoun
- E.L. Steele Laboratory for Tumor Biology, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Lance L. Munn
- E.L. Steele Laboratory for Tumor Biology, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (LLM); (RKJ)
| | - Rakesh K. Jain
- E.L. Steele Laboratory for Tumor Biology, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (LLM); (RKJ)
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Zhu Y, Harada T, Liu L, Lush ME, Guignard F, Harada C, Burns DK, Bajenaru ML, Gutmann DH, Parada LF. Inactivation of NF1 in CNS causes increased glial progenitor proliferation and optic glioma formation. Development 2007; 132:5577-88. [PMID: 16314489 PMCID: PMC2760350 DOI: 10.1242/dev.02162] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The gene responsible for neurofibromatosis type 1 (NF1) encodes a tumor suppressor that functions as a negative regulator of the Ras proto-oncogene. Individuals with germline mutations in NF1 are predisposed to the development of benign and malignant tumors of the peripheral and central nervous system (CNS). Children with this disease suffer a high incidence of optic gliomas, a benign but potentially debilitating tumor of the optic nerve; and an increased incidence of malignant astrocytoma, reactive astrogliosis and intellectual deficits. In the present study, we have sought insight into the molecular and cellular basis of NF1-associated CNS pathologies. We show that mice genetically engineered to lack NF1 in CNS exhibit a variety of defects in glial cells. Primary among these is a developmental defect resulting in global reactive astrogliosis in the adult brain and increased proliferation of glial progenitor cells leading to enlarged optic nerves. As a consequence, all of the mutant optic nerves develop hyperplastic lesions, some of which progress to optic pathway gliomas. These data point to hyperproliferative glial progenitors as the source of the optic tumors and provide a genetic model for NF1-associated astrogliosis and optic glioma.
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Affiliation(s)
- Yuan Zhu
- Center for Developmental Biology and Kent Waldrep Foundation Center for Basic Research on Nerve Growth and Regeneration, University of Texas Southwestern Medical Center, Dallas, TX 75390-9133, USA.
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Foreman NK, Gore L, Wells D, Straessle J, Heideman R, Donson AM. Gefitinib is effective against juvenile pilocytic astrocytoma in vitro. Pediatr Blood Cancer 2006; 47:293-8. [PMID: 16206208 DOI: 10.1002/pbc.20619] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Juvenile pilocytic astrocytomas (JPAs) are the most common central nervous system tumors in children. If completely resected, JPAs are associated with an excellent outcome. However, there is need for additional therapeutic approaches for those JPAs which are incompletely resected and fail subsequent standard chemotherapy/radiation. To explore the possibility for a novel therapeutic approach we measured the effect of the epidermal growth factor receptor (EGFR) small molecule tyrosine kinase inhibitor gefitinib on five JPA primary cell-cultures. PROCEDURE Due to a lack of established cell-lines of JPA very few in vitro drug sensitivity assays have been performed. In this study we have succeeded in propagating short-term primary cell-cultures established from surgical specimens. The effect of gefitinib on proliferation in JPA derived primary cell-cultures was measured by a standard tritiated thymidine incorporation assay. The level of expression of EGFR, the intended target of gefitinib, was measured by immunohistochemistry, flow cytometry and RT-PCR. RESULTS Gefitinib was shown to inhibit proliferation in all five JPA cell-cultures tested, with IC-50's between 1.6 and 9.6 microM. However, EGFR protein and mRNA expression was undetectable. Further studies with cetuximab, an EGFR-specific inhibitory monoclonal antibody, showed no effect on proliferation in JPA. CONCLUSIONS Based on these preclinical data, gefitinib may be a suitable salvage chemotherapy drug to explore further in those patients with JPA who have recurred after primary chemotherapy. Of interest, it appears that the anti-tumor effect of gefitinib in JPA cell-cultures may be mediated through a pathway other than EGFR inhibition.
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Affiliation(s)
- Nicholas K Foreman
- University of Colorado at Denver and Health Sciences Center (UCDHSC) and The Children's Hospital, Denver, Colorado.
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Rorive S, Maris C, Debeir O, Sandras F, Vidaud M, Bièche I, Salmon I, Decaestecker C. Exploring the Distinctive Biological Characteristics of Pilocytic and Low-Grade Diffuse Astrocytomas Using Microarray Gene Expression Profiles. J Neuropathol Exp Neurol 2006; 65:794-807. [PMID: 16896313 DOI: 10.1097/01.jnen.0000228203.12292.a1] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Although World Health Organization (WHO) grade I pilocytic astrocytomas and grade II diffuse astrocytomas have been classified for decades as different clinicopathologic entities, few, if any, data are available on the biologic features explaining these differences. Although more than 50 microarray-related studies have been carried out to characterize the molecular profiles of astrocytic tumors, we have identified only 11 that provide sound data on low-grade astrocytomas. We have incorporated these data into a comparative analysis for the purpose of identifying the most relevant molecular markers characterizing grade I pilocytic and grade II diffuse astrocytomas. Our analysis has identified various interesting genes that are differentially expressed in either grade I or grade II astrocytomas when compared with normal tissue and/or high-grade (WHO grade III and IV) astrocytomas. A large majority of these genes encode adhesion, extracellular matrix, and invasion-related proteins. Interestingly, a group of 6 genes (TIMP4, C1NH, CHAD, THBS4, IGFBP2, and TLE2) constitute an expression profile characteristic of grade I astrocytomas as compared with all other categories of tissue (normal brain, grade II, and high-grade astrocytomas). The end products (proteins) of these genes act as antimigratory compounds, a fact that could explain why pilocytic astrocytomas behave as compact (well-circumscribed) tumors as opposed to all the other astrocytic tumor types that diffusely invade the brain parenchyma. Having validated these molecular markers by means of real-time reverse transcriptase-polymerase chain reaction, an integrated model was proposed illustrating how and why pilocytic astrocytomas constitute a distinct biologic and pathologic entity when compared with diffuse astrocytomas.
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Affiliation(s)
- Sandrine Rorive
- Laboratory of Pathology, Erasmus University Hospital, The Netherlands
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Abstract
Central nervous system (CNS) neoplasms can be diagnostically challenging, due to remarkably wide ranges in histologic appearance, biologic behavior, and therapeutic approach. Nevertheless, accurate diagnosis is the critical first step in providing optimal patient care. As with other oncology-based specialties, there is a rapidly expanding interest and enthusiasm for identifying and utilizing new biomarkers to enhance the day-to-day practice of surgical neuropathology. In this regard, the field is primed by recent advances in basic research, elucidating the molecular mechanisms of tumorigenesis and progression in the most common adult and pediatric brain tumors. Thus far, few have made the transition into routine clinical practice, the most notable example being 1p and 19q testing in oligodendroglial tumors. However, the field is rapidly evolving and many other biomarkers are likely to emerge as useful ancillary diagnostic, prognostic, or therapeutic aids. The goal of this article is to highlight the most common genetic alterations currently implicated in CNS tumors, focusing most on those that are either already in common use in ancillary molecular diagnostics testing or are likely to become so in the near future.
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Affiliation(s)
- Christine E Fuller
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105, and Division of Neuropathology, Washington University School of Medicine, St. Louis, MO, USA.
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Abstract
Neurofibromatosis type 1 (NF1) is a common genetic condition in which affected individuals develop benign and malignant nervous system tumours. Genetically engineered mouse (GEM) models of these NF1-associated nervous system tumours recapitulate several of the unique clinical aspects of the disease. Moreover, these Nf1 GEM models allow for a direct examination of the earliest stages of tumour evolution, including the contributions that Nf1(+/-) cellular elements and cooperating genetic changes make to facilitate the transition from the pre-neoplastic to the neoplastic state and, in some cases, to promote malignant progression.
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Affiliation(s)
- Joshua B Rubin
- Department of Pediatrics, Washington University School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri 63110, USA
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Fedi M, Anne Mitchell L, Kalnins RM, Gutmann DH, Perry A, Newton M, Brodtmann A, Berkovic SF. Glioneuronal tumours in neurofibromatosis type 1: MRI-pathological study. J Clin Neurosci 2004; 11:745-7. [PMID: 15337138 DOI: 10.1016/j.jocn.2003.10.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2003] [Accepted: 10/31/2003] [Indexed: 10/26/2022]
Abstract
Neurofibromatosis type 1 (NF1) is an inherited disorder in which affected individuals develop both benign and malignant tumours at an increased frequency. Glioneuronal tumours, such as ganglioglioma and dysembryoplastic neuroepithelial tumour, have been previously reported in patients with NF1. We describe two patients with glioneuronal tumours and typical clinical features of NF1. Molecular analysis of these tumours did not demonstrate loss of the NF1 gene by fluorescence in situ hybridization (FISH) or immunohistochemistry analysis, suggesting they might not be causally associated with gross defects in NF1 expression. Because of the excellent prognosis following the resection of these tumours, it is important to distinguish them from other NF1-associated tumours.
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Affiliation(s)
- Marco Fedi
- Department of Medicine (Neurology), Austin and Repatriation Medical Centre, University of Melborne, Heidelberg, Vic., Australia
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Wowra B, Muacevic A, Müller-Schunk S, Tonn JC. Special indications in gamma knife surgery. ACTA NEUROCHIRURGICA. SUPPLEMENT 2004; 91:89-102. [PMID: 15707030 DOI: 10.1007/978-3-7091-0583-2_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Pilocytic astrocytoma (PA) represent a rare indication for Gamma Knife Surgery. Mostly small remnants after surgical debulking are treated. The prognosis depends on specific variants of biological and clinical criteria. In this regard we differentiated two groups of tumors; the so-called 'typical' tumors with a histological grading of WHO Grade I, no prior fractionated radiotherapy and no cystic component and the so called 'atypical' tumors with either a malignant transformation, previous fractionated radiotherapy and/or cystic components. The outcome after GKS was much more favourable for typical PA than for atypical. In typical cases a high tumor control with a very low risk of side effects can be achieved.
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Affiliation(s)
- B Wowra
- German Gamma Knife Centre Munich, Munich, Germany.
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Gutmann DH, James CD, Poyhonen M, Louis DN, Ferner R, Guha A, Hariharan S, Viskochil D, Perry A. Molecular analysis of astrocytomas presenting after age 10 in individuals with NF1. Neurology 2003; 61:1397-400. [PMID: 14638962 DOI: 10.1212/wnl.61.10.1397] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Fifteen to 20% of children with neurofibromatosis type 1 (NF1) develop low-grade astrocytomas. Although brain tumors are less common in teenagers and adults with NF1, recent studies have suggested that patients with NF1 are at a significantly increased risk of developing astrocytomas. OBJECTIVE S: To investigate the genetic basis for astrocytoma development in patients with NF1 beyond the first decade of life. METHODS The authors performed molecular genetic analyses of 10 NF1-associated astrocytomas representing all World Health Organization (WHO) malignancy grades using fluorescence in situ hybridization, loss of heterozygosity, immunohistochemistry, and direct sequencing. RESULTS Later-onset NF1-associated astrocytomas, unlike histologically identical sporadic astrocytomas, exhibit NF1 inactivation, supporting a direct association with NF1 rather than a chance occurrence. Furthermore, some of these astrocytomas have homozygous NF1 deletion. In addition, genetic changes observed in high-grade sporadic astrocytomas, including TP53 mutation and CDKN2A/p16 deletion, are also seen in NF1-associated high-grade astrocytomas. CONCLUSIONS Neurofibromatosis type 1-associated astrocytomas occurring in patients older than 10 years exhibit genetic changes observed in sporadic high-grade astrocytomas. Patients with neurofibromatosis type 1 and germline NF1 deletions may be at risk for developing late-onset astrocytomas.
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Affiliation(s)
- D H Gutmann
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Abstract
Neurofibromatosis type 1 (NF1) patients are predisposed to learning disabilities, macrocephaly, and brain tumors as well as abnormalities on magnetic resonance imaging that are postulated to result from abnormal myelination. Here we show that Nf1+/- spinal cords in adult mice have more than twofold-increased numbers of NG2+ progenitor cells. Nf1-/- embryonic spinal cords have increased numbers of Olig2+ progenitors. Also, cultures from Nf1 mutant embryos with hemizygous and biallelic Nf1 mutations have dramatically increased numbers of CNS oligodendrocyte progenitor cells. In medium that allows growth of neuroepithelial cells and glial progenitors, mutant cells hyper-respond to FGF2, have increased basal and FGF-stimulated Ras-GTP, and fail to accumulate when treated with a farnesyltransferase inhibitor. Cell accumulation results in part from increased proliferation and decreased cell death. In contrast to wild-type cells, Nf1-/- progenitors express the glial differentiation marker O4 while retaining expression of the progenitor marker nestin. Nf1 mutant progenitors also abnormally coexpress the glial differentiation markers O4 and GFAP. Importantly, Nf1-/- spinal cord-derived oligodendrocyte progenitors, which are amplified 12-fold, retain the ability to form oligodendrocytes after in vivo transplantation. The data reveal a key role for neurofibromin and Ras signaling in the maintenance of CNS progenitor cell pools and also suggest a potential role for progenitor cell defects in the CNS abnormalities of NF1 patients.
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Hughes JAI, Cooke-Yarborough CM, Chadwick NC, Schevzov G, Arbuckle SM, Gunning P, Weinberger RP. High-molecular-weight tropomyosins localize to the contractile rings of dividing CNS cells but are absent from malignant pediatric and adult CNS tumors. Glia 2003; 42:25-35. [PMID: 12594734 DOI: 10.1002/glia.10174] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Tropomyosin has been implicated in the control of actin filament dynamics during cell migration, morphogenesis, and cytokinesis. In order to gain insight into the role of tropomyosins in cell division, we examined their expression in developing and neoplastic brain tissue. We found that the high-molecular-weight tropomyosins are downregulated at birth, which correlates with glial cell differentiation and withdrawal of most cells from the cell cycle. Expression of these isoforms was restricted to proliferative areas in the embryonic brain and was absent from the adult, where the majority of cells are quiescent. However, they were induced under conditions where glial cells became proliferative in response to injury. During cytokinesis, these tropomyosin isoforms were associated with the contractile ring. We also investigated tropomyosin expression in neoplastic CNS tissues. Low-grade astrocytic tumors expressed high-molecular-weight tropomyosins, while highly malignant CNS tumors of diverse origin did not (P </= 0.001). Furthermore, high-molecular-weight tropomyosins were absent from the contractile ring in highly malignant astrocytoma cells. Our findings suggest a role for high-molecular-weight tropomyosins in astrocyte cytokinesis, although highly malignant CNS tumors are still able to undergo cell division in their absence. Additionally, the correlation between high-molecular-weight tropomyosin expression and tumor grade suggests that tropomyosins are potentially useful as indicators of CNS tumor grade.
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Affiliation(s)
- Julie A I Hughes
- Oncology Research Unit, Children's Hospital at Westmead, Australia
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Abstract
Neurofibromatosis 1 (NF1) is a common genetic condition in which affected individuals are prone to the development of benign and malignant tumors. The NF1 tumor suppressor encodes a protein product, neurofibromin, which functions in part as a negative regulator of RAS. Loss of neurofibromin expression in NF1-associated tumors or Nf1-deficient mouse cells is associated with elevated RAS activity and increased cell proliferation. Despite this straightforward pathophysiologic association between neurofibromin, RAS, and tumorigenesis, recent insights from mouse and Drosophila modeling studies have suggested additional functions for neurofibromin and have implicated Nf1 heterozygosity in tumor formation. Lastly, Nf1 knockout mouse studies have also demonstrated important roles for cooperating genetic changes that accelerate tumorigenesis as well as modifier genes that impact on cancer susceptibility.
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Affiliation(s)
- Biplab Dasgupta
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Abstract
Neurofibromatosis 1 is one of the most common autosomal dominant disorders affecting the nervous system. Individuals with neurofibromatosis 1 present with abnormalities of both astrocytes and neurons that result from reduced or absent expression of the NF1 gene product neurofibromin. Impaired neurofibromin function in these nervous system cells contributes to the development of astrocytomas, learning disabilities, and radiographic abnormalities of the brain. With the identification of NF1, significant advances have begun to unlock some of the mysteries that surround the molecular pathogenesis of neurofibromatosis 1-associated brain abnormalities. With continued advances in our basic understanding of NF1 function, future targeted therapies for neurofibromatosis 1-associated central nervous system abnormalities can be developed.
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Affiliation(s)
- David H Gutmann
- Department of Neurology, Washington University School of Medicine, and The Neurofibromatosis Program, St. Louis Children's Hospital, MO 63110, USA.
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Gutmann DH, Giovannini M. Mouse models of neurofibromatosis 1 and 2. Neoplasia 2002; 4:279-90. [PMID: 12082543 PMCID: PMC1531708 DOI: 10.1038/sj.neo.7900249] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2002] [Accepted: 03/08/2002] [Indexed: 11/08/2022]
Abstract
The neurofibromatoses represent two of the most common inherited tumor predisposition syndromes affecting the nervous system. Individuals with neurofibromatosis 1 (NF1) are prone to the development of astrocytomas and peripheral nerve sheath tumors whereas those affected with neurofibromatosis 2 (NF2) develop schwannomas and meningiomas. The development of traditional homozygous knockout mice has provided insights into the roles of the NF1 and NF2 genes during development and in differentiation, but has been less instructive regarding the contribution of NF1 and NF2 dysfunction to the pathogenesis of specific benign and malignant tumors. Recent progress employing novel mouse targeting strategies has begun to illuminate the roles of the NF1 and NF2 gene products in the molecular pathogenesis of NF-associated tumors.
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Affiliation(s)
- David H Gutmann
- Department of Neurology, Washington University School of Medicine, Box 8111, 660 S. Euclid Avenue, St. Louis, MO 63110, USA.
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Bajenaru ML, Zhu Y, Hedrick NM, Donahoe J, Parada LF, Gutmann DH. Astrocyte-specific inactivation of the neurofibromatosis 1 gene (NF1) is insufficient for astrocytoma formation. Mol Cell Biol 2002; 22:5100-13. [PMID: 12077339 PMCID: PMC139771 DOI: 10.1128/mcb.22.14.5100-5113.2002] [Citation(s) in RCA: 239] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2002] [Revised: 04/04/2002] [Accepted: 04/19/2002] [Indexed: 11/20/2022] Open
Abstract
Individuals with the neurofibromatosis 1 (NF1) inherited tumor syndrome develop low-grade gliomas (astrocytomas) at an increased frequency, suggesting that the NF1 gene is a critical growth regulator for astrocytes. In an effort to determine the contribution of the NF1 gene product, neurofibromin, to astrocyte growth regulation and NF1-associated astrocytoma formation, we generated astrocyte-specific Nf1 conditional knockout mice (Nf1(GFAP)CKO) by using Cre/LoxP technology. Transgenic mice were developed in which Cre recombinase was specifically expressed in astrocytes by embryonic day 14.5. Successive intercrossing with mice bearing a conditional Nf1 allele (Nf1flox) resulted in GFAP-Cre Nf1flox/flox (Nf1(GFAP)CKO) animals. No astrocytoma formation or neurological impairment was observed in Nf1(GFAP)CKO mice after 20 months, but increased numbers of proliferating astrocytes were observed in several brain regions. To determine the consequence of Nf1 inactivation at different developmental times, the growth properties of embryonic day 12.5 and postnatal day 2 Nf1 null astrocytes were analyzed. Nf1 null astrocytes exhibited increased proliferation but lacked tumorigenic properties in vitro and did not form tumors when injected into immunocompromised mouse brains in vivo. Collectively, our results suggest that loss of neurofibromin is not sufficient for astrocytoma formation in mice and that other genetic or environmental factors might influence NF1-associated glioma tumorigenesis.
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Affiliation(s)
- Michaela Livia Bajenaru
- Department of Neurology, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, MO 63110, USA
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Fuller CE, Perry A. Fluorescence in situ hybridization (FISH) in diagnostic and investigative neuropathology. Brain Pathol 2002; 12:67-86. [PMID: 11770903 PMCID: PMC8095867 DOI: 10.1111/j.1750-3639.2002.tb00424.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Over the last decade, fluorescence in situ hybridization (FISH) has emerged as a powerful clinical and research tool for the assessment of target DNA dosages within interphase nuclei. Detectable alterations include aneusomies, deletions, gene amplifications, and translocations, with primary advantages to the pathologist including its basis in morphology, its applicability to archival, formalin-fixed paraffin-embedded (FFPE) material, and its similarities to immunohistochemistry. Recent technical advances such as improved hybridization protocols, markedly expanded probe availability resulting from the human genome sequencing initiative, and the advent of high-throughput assays such as gene chip and tissue microarrays have greatly enhanced the applicability of FISH. In our lab, we currently utilize only a limited battery of DNA probes for routine diagnostic purposes, with determination of chromosome 1p and 19q dosage in oligodendroglial neoplasms representing the most common application. However, research applications are numerous and will likely translate into a growing list of clinically useful markers in the near future. In this review, we highlight the advantages and disadvantages of FISH and familiarize the reader with current applications in diagnostic and investigative neuropathology.
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Affiliation(s)
- Christine E. Fuller
- Division of Neuropathology, Washington University School of Medicine, St. Louis, Mo
| | - Arie Perry
- Division of Neuropathology, Washington University School of Medicine, St. Louis, Mo
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Millichap JG. NF1-Associated Astrocytomas. Pediatr Neurol Briefs 2001. [DOI: 10.15844/pedneurbriefs-15-5-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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