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Martins EP, Gonçalves CS, Pojo M, Carvalho R, Ribeiro AS, Miranda‐Gonçalves V, Taipa R, Pardal F, Pinto AA, Custódia C, Faria CC, Baltazar F, Sousa N, Paredes J, Costa BM. Cadherin‐3
is a novel oncogenic biomarker with prognostic value in glioblastoma. Mol Oncol 2021; 16:2611-2631. [PMID: 34919784 PMCID: PMC9297769 DOI: 10.1002/1878-0261.13162] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 12/01/2021] [Accepted: 12/15/2021] [Indexed: 11/08/2022] Open
Abstract
Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. The prognosis of patients is very poor, with a median overall survival of ~ 15 months after diagnosis. Cadherin‐3 (also known as P‐cadherin), a cell–cell adhesion molecule encoded by the CDH3 gene, is deregulated in several cancer types, but its relevance in GBM is unknown. In this study, we investigated the functional roles, the associated molecular signatures, and the prognostic value of CDH3/P‐cadherin in this highly malignant brain tumor. CDH3/P‐cadherin mRNA and protein levels were evaluated in human glioma samples. Knockdown and overexpression models of P‐cadherin in GBM were used to evaluate its functional role in vitro and in vivo. CDH3‐associated gene signatures were identified by enrichment analyses and correlations. The impact of CDH3 in the survival of GBM patients was assessed in independent cohorts using both univariable and multivariable models. We found that P‐cadherin protein is expressed in a subset of gliomas, with an increased percentage of positive samples in grade IV tumors. Concordantly, CDH3 mRNA levels in glioma samples from The Cancer Genome Atlas (TCGA) database are increased in high‐grade gliomas. P‐cadherin displays oncogenic functions in multiple knockdown and overexpression GBM cell models by affecting cell viability, cell cycle, cell invasion, migration, and neurosphere formation capacity. Genes that were positively correlated with CDH3 are enriched for oncogenic pathways commonly activated in GBM. In vivo, GBM cells expressing high levels of P‐cadherin generate larger subcutaneous tumors and cause shorter survival of mice in an orthotopic intracranial model. Concomitantly, high CDH3 expression is predictive of shorter overall survival of GBM patients in independent cohorts. Together, our results show that CDH3/P‐cadherin expression is associated with aggressiveness features of GBM and poor patient prognosis, suggesting that it may be a novel therapeutic target for this deadly brain tumor.
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Affiliation(s)
- Eduarda P. Martins
- Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Campus Gualtar 4710‐057 Braga Portugal
- ICVS/3B’s ‐ PT Government Associate Laboratory Braga/Guimarães Portugal
| | - Céline S. Gonçalves
- Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Campus Gualtar 4710‐057 Braga Portugal
- ICVS/3B’s ‐ PT Government Associate Laboratory Braga/Guimarães Portugal
| | - Marta Pojo
- Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Campus Gualtar 4710‐057 Braga Portugal
- ICVS/3B’s ‐ PT Government Associate Laboratory Braga/Guimarães Portugal
| | - Rita Carvalho
- i3S – Instituto de Investigação e Inovação em Saúde Universidade do Porto Rua Alfredo Allen 208, 4200‐135 Porto Portugal
| | - Ana S. Ribeiro
- i3S – Instituto de Investigação e Inovação em Saúde Universidade do Porto Rua Alfredo Allen 208, 4200‐135 Porto Portugal
| | - Vera Miranda‐Gonçalves
- Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Campus Gualtar 4710‐057 Braga Portugal
- ICVS/3B’s ‐ PT Government Associate Laboratory Braga/Guimarães Portugal
| | - Ricardo Taipa
- Neuropathology Unit Department of Neurosciences Centro Hospitalar do Porto Porto Portugal
| | - Fernando Pardal
- Department of Pathology, Hospital de Braga 4710‐243 Braga Portugal
| | - Afonso A. Pinto
- Department of Neurosurgery, Hospital de Braga 4710‐243 Braga Portugal
| | - Carlos Custódia
- Instituto de Medicina Molecular Faculdade de Medicina Universidade de Lisboa Lisbon Portugal
| | - Cláudia C. Faria
- Instituto de Medicina Molecular Faculdade de Medicina Universidade de Lisboa Lisbon Portugal
- Neurosurgery Department Hospital de Santa Maria Centro Hospitalar Lisboa Norte (CHLN) Lisbon Portugal
| | - Fátima Baltazar
- Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Campus Gualtar 4710‐057 Braga Portugal
- ICVS/3B’s ‐ PT Government Associate Laboratory Braga/Guimarães Portugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Campus Gualtar 4710‐057 Braga Portugal
- ICVS/3B’s ‐ PT Government Associate Laboratory Braga/Guimarães Portugal
| | - Joana Paredes
- i3S – Instituto de Investigação e Inovação em Saúde Universidade do Porto Rua Alfredo Allen 208, 4200‐135 Porto Portugal
- Faculty of Medicine University of Porto Portugal
| | - Bruno M. Costa
- Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Campus Gualtar 4710‐057 Braga Portugal
- ICVS/3B’s ‐ PT Government Associate Laboratory Braga/Guimarães Portugal
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Liu Q, Wang Q, Lv C, Liu Z, Gao H, Chen Y, Zhao G. Brucine inhibits proliferation of glioblastoma cells by targeting the G-quadruplexes in the c-Myb promoter. J Cancer 2021; 12:1990-1999. [PMID: 33753997 PMCID: PMC7974541 DOI: 10.7150/jca.53689] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 01/04/2021] [Indexed: 11/10/2022] Open
Abstract
The proto-oncogene c-Myb plays an important role in cell proliferation, and its upregulation affects the development of glioblastomas. G-quadruplexes are secondary DNA or RNA structures that usually form in the promoter region of oncogenes, including c-Myb, and regulate the expression of these genes. The traditional Chinese medicine, brucine, is a ligand of the G-quadruplexes located in the promoter region of c-Myb. The present study investigated the therapeutic effects and mechanism of action of brucine in U87, LN18, and LN229 cells in vitro and in vivo. Our results showed that brucine suppressed the growth of these cells in vitro by arresting the cell cycle and reducing c-Myb expression. Dual-luciferase reporter assays showed that brucine inhibited c-Myb expression by targeting the guanine-rich sequence that forms G-quadruplexes in the c-Myb promoter. Moreover, U87 tumors were suppressed by brucine in a tumor xenograft nude mouse model. Therefore, brucine is potentially effective for treating glioblastomas.
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Affiliation(s)
- Qiaochu Liu
- Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China.,Clinical College, Jilin University, Changchun, China
| | - Qunhui Wang
- Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China.,Clinical College, Jilin University, Changchun, China
| | - Chuanqi Lv
- Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China.,Clinical College, Jilin University, Changchun, China
| | - Ziqiang Liu
- Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China.,Clinical College, Jilin University, Changchun, China
| | - Haijun Gao
- Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China.,Clinical College, Jilin University, Changchun, China
| | - Yong Chen
- Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China.,Clinical College, Jilin University, Changchun, China
| | - Gang Zhao
- Department of Neurosurgery, The First Hospital of Jilin University, Changchun, China.,Clinical College, Jilin University, Changchun, China
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Abstract
The c-Myb gene encodes a transcription factor that regulates cell proliferation, differentiation, and apoptosis through protein-protein interaction and transcriptional regulation of signaling pathways. The protein is frequently overexpressed in human leukemias, breast cancers, and other solid tumors suggesting that it is a bona fide oncogene. c-MYB is often overexpressed by translocation in human tumors with t(6;7)(q23;q34) resulting in c-MYB-TCRβ in T cell ALL, t(X;6)(p11;q23) with c-MYB-GATA1 in acute basophilic leukemia, and t(6;9)(q22-23;p23-24) with c-MYB-NF1B in adenoid cystic carcinoma. Antisense oligonucleotides to c-MYB were developed to purge bone marrow cells to eliminate tumor cells in leukemias. Recently, small molecules that inhibit c-MYB activity have been developed to disrupt its interaction with p300. The Dmp1 (cyclin D binding myb-like protein 1; Dmtf1) gene was isolated through its virtue for binding to cyclin D2. It is a transcription factor that has a Myb-like repeat for DNA binding. The Dmtf1 protein directly binds to the Arf promoter for transactivation and physically interacts with p53 to activate the p53 pathway. The gene is hemizygously deleted in 35-42% of human cancers and is associated with longer survival. The significances of aberrant expression of c-MYB and DMTF1 proteins in human cancers and their clinical significances are discussed.
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Affiliation(s)
- Elizabeth A. Fry
- The Department of Pathology, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157 USA
| | - Kazushi Inoue
- The Department of Pathology, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157 USA
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Aibaidula A, Chan AKY, Shi Z, Li Y, Zhang R, Yang R, Li KKW, Chung NYF, Yao Y, Zhou L, Wu J, Chen H, Ng HK. Adult IDH wild-type lower-grade gliomas should be further stratified. Neuro Oncol 2018; 19:1327-1337. [PMID: 28575485 DOI: 10.1093/neuonc/nox078] [Citation(s) in RCA: 153] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Background Astrocytoma of the isocitrate dehydrogenase (IDH) wild-type gene is described as a provisional entity within the new World Health Organization (WHO) classification. Some groups believe that IDH wild-type lower-grade gliomas, when interrogated for other biomarkers, will mostly turn out to be glioblastoma. We hypothesize that not all IDH wild-type lower-grade gliomas have very poor outcomes and the group could be substratified prognostically. Methods Seven hundred and eighteen adult WHO grades II and III patients with gliomas from our hospitals were re-reviewed and tested for IDH1/2 mutations. One hundred and sixty-six patients with IDH wild-type cases were identified for further studies, and EGFR and MYB amplifications, mutations of histone H3F3A, TERT promoter (TERTp), and BRAF were examined. Results EGFR amplification, BRAF, and H3F3A mutations were observed in 13.8%, 6.9%, and 9.5% of patients, respectively, in a mutually exclusive pattern in IDH wild-type lower-grade gliomas. TERTp mutations were detected in 26.8% of cases. Favorable outcome was observed in patients with young age, oligodendroglial phenotype, and grade II histology. Independent adverse prognostic values of older age, nontotal resection, grade III histology, EGFR amplification, and H3F3A mutation were confirmed by multivariable analysis. Tumors were further classified into "molecularly" high grade (harboring EGFR, H3F3A, or TERTp) (median overall survival = 1.23 y) and lower grade (lacking all of the 3) (median overall survival = 7.63 y) with independent prognostic relevance. The most favorable survival was noted in molecularly lower-grade gliomas with MYB amplification. Conclusion Adult IDH wild-type lower-grade gliomas are prognostically heterogeneous and do not have uniformly poor prognosis. Clinical information and additional markers, including MYB, EGFR, TERTp, and H3F3A, should be examined to delineate discrete favorable and unfavorable prognostic groups.
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Affiliation(s)
- Abudumijit Aibaidula
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Aden Ka-Yin Chan
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Zhifeng Shi
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yanxi Li
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Ruiqi Zhang
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Rui Yang
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Kay Ka-Wai Li
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Nellie Yuk-Fei Chung
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yu Yao
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Liangfu Zhou
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Jinsong Wu
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Hong Chen
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
| | - Ho-Keung Ng
- Department of Anatomical and Cellular Pathology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China; Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, China); Department of Pathology, Huashan Hospital, Fudan University, Shanghai, China
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Nasser MM, Mehdipour P. Exploration of Involved Key Genes and Signaling Diversity in Brain Tumors. Cell Mol Neurobiol 2018; 38:393-419. [PMID: 28493234 DOI: 10.1007/s10571-017-0498-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Accepted: 05/02/2017] [Indexed: 02/05/2023]
Abstract
Brain tumors are becoming a major cause of death. The classification of brain tumors has gone through restructuring with regard to some criteria such as the presence or absence of a specific genetic alteration in the 2016 central nervous system World Health Organization update. Two categories of genes with a leading role in tumorigenesis and cancer induction include tumor suppressor genes and oncogenes; tumor suppressor genes are inactivated through a variety of mechanisms that result in their loss of function. As for the oncogenes, overexpression and amplification are the most common mechanisms of alteration. Important cell cycle genes such as p53, ATM, cyclin D2, and Rb have shown altered expression patterns in different brain tumors such as meningioma and astrocytoma. Some genes in signaling pathways have a role in brain tumorigenesis. These pathways include hedgehog, EGFR, Notch, hippo, MAPK, PI3K/Akt, and WNT signaling. It has been shown that telomere length in some brain tumor samples is shortened compared to that in normal cells. As the shortening of telomere length triggers chromosome instability early in brain tumors, it could lead to initiation of cancer. On the other hand, telomerase activity was positive in some brain tumors. It is suggestive that telomere length and telomerase activity are important diagnostic markers in brain tumors. This review focuses on brain tumors with regard to the status of oncogenes, tumor suppressors, cell cycle genes, and genes in signaling pathways as well as the role of telomere length and telomerase in brain tumors.
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Affiliation(s)
- Mojdeh Mahdian Nasser
- Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Parvin Mehdipour
- Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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6
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Gu J, Lu Z, Ji C, Chen Y, Liu Y, Lei Z, Wang L, Zhang HT, Li X. Melatonin inhibits proliferation and invasion via repression of miRNA-155 in glioma cells. Biomed Pharmacother 2017; 93:969-975. [PMID: 28724215 DOI: 10.1016/j.biopha.2017.07.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 06/14/2017] [Accepted: 07/03/2017] [Indexed: 01/01/2023] Open
Abstract
Melatonin, an indolamine mostly synthesized in the pineal gland, exerts the anti-cancer effect by various mechanisms in glioma cells. Our previous study showed that miR-155 promoted glioma cell proliferation and invasion. However, the question of whether melatonin may inhibit glioma by regulating miRNAs has not yet been addressed. In this study, we found that melatonin (100μM, 1μM and 1nM) significantly inhibited the expression of miR-155 in human glioma cell lines U87, U373 and U251. Especially, the lowest expression of miR-155 was detected in 1μM melatonin-treated glioma cells. Melatonin (1μM) inhibits cell proliferation of U87 by promoting cell apoptosis. Nevertheless, melatonin had no effect on cell cycle distribution of U87 cells. Moreover, U87 cells treated with 1μM melatonin presented significantly lower migration and invasion ability when compared with control cells. Importantly, melatonin inhibited c-MYB expression, and c-MYB knockdown reduced miR-155 expression and migration and invasion in U87 cells. Taken together, for the first time, our findings show that melatonin inhibits miR-155 expression and thereby represses glioma cell proliferation, migration and invasion, and suggest that melatonin may downregulate the expression of miR-155 via repression of c-MYB. This will provide a theoretical basis for revealing the anti-glioma mechanisms of melatonin.
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Affiliation(s)
- Junyi Gu
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Medical College of Soochow University, Suzhou 215006, China; Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou 215123, China
| | - Zhongsheng Lu
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Medical College of Soochow University, Suzhou 215006, China; Department of Neurological Surgery, Qinghai Provincial People's Hospital, Xi'ning 810007, China
| | - Chenghong Ji
- The Second Affiliated Hospital of Soochow University, Medical College of Soochow University, Suzhou 215004, China
| | - Yuchao Chen
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Medical College of Soochow University, Suzhou 215006, China
| | - Yuzhao Liu
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Medical College of Soochow University, Suzhou 215006, China
| | - Zhe Lei
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou 215123, China; Suzhou Key Laboratory for Molecular Cancer Genetics, Suzhou 215123, China
| | - Longqiang Wang
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou 215123, China; Suzhou Key Laboratory for Molecular Cancer Genetics, Suzhou 215123, China
| | - Hong-Tao Zhang
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou 215123, China; Suzhou Key Laboratory for Molecular Cancer Genetics, Suzhou 215123, China.
| | - Xiangdong Li
- Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Medical College of Soochow University, Suzhou 215006, China; Suzhou Key Laboratory for Molecular Cancer Genetics, Suzhou 215123, China.
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7
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Overexpression of c-Myb is associated with suppression of distant metastases in colorectal carcinoma. Tumour Biol 2016; 37:10723-9. [DOI: 10.1007/s13277-016-4956-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/02/2016] [Indexed: 01/09/2023] Open
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Myb and the Regulation of Stem Cells in the Intestine and Brain: A Tale of Two Niches. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 786:353-68. [DOI: 10.1007/978-94-007-6621-1_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Sarvaiya PJ, Schwartz JR, Hernandez CP, Rodriguez PC, Vedeckis WV. Role of c-Myb in the survival of pre B-cell acute lymphoblastic leukemia and leukemogenesis. Am J Hematol 2012; 87:969-76. [PMID: 22764095 DOI: 10.1002/ajh.23283] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 05/10/2012] [Accepted: 05/22/2012] [Indexed: 12/26/2022]
Abstract
Acute lymphoblastic leukemia (ALL) is the most common cancer in children. The current treatment protocol for ALL involves an intense chemotherapy regimen yielding cure rates of nearly 80%. However, new therapies need to be designed not only to increase the survival rate but also to combat the risk of severe therapy associated toxicities including secondary malignancies, growth problems, organ damage, and infertility. The c-Myb proto-oncogene is highly expressed in immature hematopoietic cells. In this study, we demonstrate that loss of c-Myb itself decreased the viability of these leukemic cells. Additionally, the inhibition of c-Myb caused a decrease in cell proliferation, significantly increased the number of cells in G(0) /G(1) phase of the cell cycle, increased the sensitivity of pre-B-ALL cells to cytotoxic agents in vitro, and significantly delayed disease onset in a mouse model of leukemia. Furthermore, we demonstrate that Bcl-2 is a target of c-Myb in pre-B-ALL cells. Our results identify c-Myb as a potential therapeutic target in pre-B-ALL and suggest that suppression of c-Myb levels or activity, in combination with currently used therapies and/or dose reduction, may lead to a decrease in toxicity and an increase in patient survival rates. Because c-Myb is aberrantly expressed in several other malignancies, targeting c-Myb will have broad clinical applications.
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Affiliation(s)
- Purvaba J Sarvaiya
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, New Orleans, LA, USA
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10
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Zhou Y, Ness SA. Myb proteins: angels and demons in normal and transformed cells. Front Biosci (Landmark Ed) 2011; 16:1109-31. [PMID: 21196221 DOI: 10.2741/3738] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A key regulator of proliferation, differentiation and cell fate, the c-Myb transcription factor regulates the expression of hundreds of genes and is in turn regulated by numerous pathways and protein interactions. However, the most unique feature of c-Myb is that it can be converted into an oncogenic transforming protein through a few mutations that completely change its activity and specificity. The c-Myb protein is a myriad of interactions and activities rolled up in a protein that controls proliferation and differentiation in many different cell types. Here we discuss the background and recent progress that have led to a better understanding of this complex protein, and outline the questions that have yet to be answered.
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Affiliation(s)
- Ye Zhou
- Department of Molecular Genetics and Microbiology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131-0001, USA
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Stenman G, Andersson MK, Andrén Y. New tricks from an old oncogene: gene fusion and copy number alterations of MYB in human cancer. Cell Cycle 2010; 9:2986-95. [PMID: 20647765 DOI: 10.4161/cc.9.15.12515] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
MYB is a leucine zipper transcription factor that is essential for hematopoesis and for renewal of colonic crypts. There is also ample evidence showing that MYB is leukemogenic in several animal species. However, it was not until recently that clear evidence was presented showing that MYB actually is an oncogene rearranged in human cancer. In a recent study, a novel mechanism of activation of MYB involving gene fusion was identified in carcinomas of the breast and head and neck. A t(6;9) translocation was shown to generate fusions between MYB and the transcription factor gene NFIB. The fusions consistently result in loss of the 3'-end of MYB, including several highly conserved target sites for microRNAs that negatively regulate MYB expression. Deletion of these target sites may disrupt the repression of MYB, leading to overexpression of MYB-NFIB transcripts and protein and to transcriptional activation of critical MYB target genes associated with apoptosis, cell cycle control, cell growth/angiogenesis and cell adhesion. This study, together with previous and recent data showing rearrangements and copy number alterations of the MYB locus in T-cell leukemia and certain solid tumors, will be the main focus of this review.
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Affiliation(s)
- Göran Stenman
- Lundberg Laboratory for Cancer Research, Department of Pathology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
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12
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O'Neil J, Tchinda J, Gutierrez A, Moreau L, Maser RS, Wong KK, Li W, McKenna K, Liu XS, Feng B, Neuberg D, Silverman L, DeAngelo DJ, Kutok JL, Rothstein R, DePinho RA, Chin L, Lee C, Look AT. Alu elements mediate MYB gene tandem duplication in human T-ALL. ACTA ACUST UNITED AC 2007; 204:3059-66. [PMID: 18070937 PMCID: PMC2150982 DOI: 10.1084/jem.20071637] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Recent studies have demonstrated that the MYB oncogene is frequently duplicated in human T cell acute lymphoblastic leukemia (T-ALL). We find that the human MYB locus is flanked by 257-bp Alu repeats and that the duplication is mediated somatically by homologous recombination between the flanking Alu elements on sister chromatids. Nested long-range PCR analysis indicated a low frequency of homologous recombination leading to MYB tandem duplication in the peripheral blood mononuclear cells of approximately 50% of healthy individuals, none of whom had a MYB duplication in the germline. We conclude that Alu-mediated MYB tandem duplication occurs at low frequency during normal thymocyte development and is clonally selected during the molecular pathogenesis of human T-ALL.
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Affiliation(s)
- Jennifer O'Neil
- Department of Pediatric Oncology, Belfer Foundation Institute for Innovative Cancer Science, Dana-Farber Cancer Institute, Boston, MA 02115, USA
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13
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[ST1]: Proto‐oncogene c‐Myb regulates neural progenitor proliferation in adult brain. Int J Dev Neurosci 2006. [DOI: 10.1016/j.ijdevneu.2006.09.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Guerreiro JR, Winnischofer SMB, Bastos MF, Portaro FCV, Sogayar MC, de Camargo ACM, Hayashi MAF. Cloning and characterization of the human and rabbit NUDEL-oligopeptidase promoters and their negative regulation. ACTA ACUST UNITED AC 2005; 1730:77-84. [PMID: 16005531 DOI: 10.1016/j.bbaexp.2005.06.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Revised: 05/30/2005] [Accepted: 06/02/2005] [Indexed: 12/19/2022]
Abstract
NUDEL-oligopeptidase is a cytosolic cysteine peptidase, active towards oligopeptides and involved in the conversion and inactivation of a number of bioactive peptides. This protein interacts with neuronal proteins and is essential for brain development and cortical organization during embryogenesis. In this study, 5'-flanking sequences of the human and rabbit NUDEL-oligopeptidase gene were cloned into the pGL3 reporter gene vector and the promoter activity of the full-length fragment and deletions series was measured in transient transfection assays using two different cell lines, namely, C6 rat glioma and NH15 human neuroblastoma. Overall, a very similar pattern of promoter activity was obtained for both rabbit and human NUDEL-oligopeptidase promoter sequences, and their respective serial deletion constructs upon transient transfection into these cell lines. The only exception was for the longest rabbit upstream sequence that displayed about 1.8-fold higher luciferase expression upon transfection into NH15 neuronal cells than that observed upon transfection into C6 glioma cells. On the other hand, no significant difference was observed for the human longest sequence. These results are in good agreement with the expression pattern of NUDEL-oligopeptidase in human and rabbit tissues.
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Affiliation(s)
- Juliano R Guerreiro
- Laboratory for Applied Toxinology, Butantan Institute, São Paulo, 05503-900, Brazil
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15
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Shin DH, Lee E, Joo KM, Kim J, Bae SR, Chung YH, Cha CI. Immunocytochemical study on the distribution of c-myb in the central nervous system of the transgenic mice expressing a human copper/zinc superoxide dismutase mutation. Neurosci Lett 2003; 350:149-52. [PMID: 14550916 DOI: 10.1016/s0304-3940(03)00901-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Although our previous study showed the constitutive expression of c-myb in neurons, suggesting that this gene might be involved in the normal function of these cells, there were no reports on the expression pattern of c-myb under pathological conditions. In the present study, we first investigated the changes in c-myb immunoreactivities (IRs) in the central nervous system of the transgenic mice expressing a human copper/zinc superoxide dismutase (Cu/Zn SOD) mutation. The distribution of c-myb was enhanced in the various brain regions of transgenic mice expressing a mutated human Cu/Zn SOD gene. Immunohistochemistry showed intensely stained c-myb IR glial cells with the appearance of astrocytes within the various brain regions of transgenic mice such as the gray matter of the midbrain, medulla oblongata and spinal cord. Even though the exact functions of c-myb in the normal and pathological states were not clearly revealed until now, we think that the increase in c-myb expression in the mutant mice could be due to the compensate mechanism of the astrocytes for the reduced defence against superoxide toxicity because the only known function of c-myb was its correlation with the prevention of programmed cell death, which could be deduced from the previous studies.
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Affiliation(s)
- Dong Hoon Shin
- Department of Anatomy, Seoul National University College of Medicine, Chongno-Gu, Yongon-Dong 28, Seoul 110-799, South Korea
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16
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Reifenberger G, Kaulich K, Wiestler OD, Blümcke I. Expression of the CD34 antigen in pleomorphic xanthoastrocytomas. Acta Neuropathol 2003; 105:358-64. [PMID: 12624789 DOI: 10.1007/s00401-002-0652-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2002] [Revised: 10/29/2002] [Accepted: 10/29/2002] [Indexed: 11/30/2022]
Abstract
Pleomorphic xanthoastrocytoma (PXA) is a rare, superficially located astrocytic glioma of children and young adults, which is associated with a relatively favorable prognosis. Here we report on the expression of the hematopoietic progenitor cell and vascular endothelial cell associated antigen CD34 in PXAs. We found CD34 immunoreactivity in various fractions of tumor cells in 44 of 60 PXAs investigated (73%). CD34 expression was more common in PXAs of WHO grade II (37 of 44 tumors, 84%) than in PXAs with anaplastic features (7 of 16 tumors, 44%). Immunoreactivity for CD34 was also commonly detected in single or clustered dysplastic neural cells within the cerebral cortex adjacent to the PXAs. Reverse transcription-PCR revealed that PXAs express the full-length CD34 transcript and a known splice variant encoding a truncated form of CD34. Both transcripts were detectable at higher levels in PXAs as compared to diffuse astrocytomas and non-neoplastic brain tissue. Taken together, our findings demonstrate that PXAs frequently express CD34 not only in vascular endothelial cells but also in tumor cells and in dysplastic cells of the adjacent cortex. Therefore, immunostaining for CD34 may be a helpful tool for the histological differential diagnosis of PXAs.
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Affiliation(s)
- G Reifenberger
- Department of Neuropathology, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany.
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17
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Kataoka Y, Murley JS, Khodarev NN, Weichselbaum RR, Grdina DJ. Activation of the nuclear transcription factor kappaB (NFkappaB) and differential gene expression in U87 glioma cells after exposure to the cytoprotector amifostine. Int J Radiat Oncol Biol Phys 2002; 53:180-9. [PMID: 12007958 DOI: 10.1016/s0360-3016(01)02820-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE Amifostine has been approved as a therapy to decrease the incidence of moderate-to-severe xerostomia in patients undergoing postoperative radiation treatment for head-and-neck cancer. As a reducing agent capable of participating in intracellular reductive/oxidative processes, it has the potential to affect redox-sensitive transcription factors and gene expression. Amifostine's active free thiol WR-1065 was investigated to determine its effect on nuclear transcription factor kappaB (NFkappaB) activation and subsequent gene expression in U87 glioma cells. METHODS AND MATERIALS The human glioma cell line U87 was grown to confluency and then exposed to WR-1065 at a concentration of 40 microM for times ranging from 30 min to 24 h. Changes in cell cycle were monitored by flow cytometry. The effect of WR-1065 on NFkappaB activation was determined by a gel shift assay. Changes in gene expression as a function of time of exposure to WR-1065 were determined by Northern blot and the Atlas Human cDNA Expression Array (Clontech, Palo Alto, CA). Changes in gene expression using the Atlas Array were verified by reverse transcriptase-polymerase chain reaction (RT-PCR) with gene-specific primers. RESULTS Exposure of U87 cells to 40 microM WR-1065 resulted in a marked activation of NFkappaB between 30 min and 1 h after treatment. Expression of MnSOD, an NFkappaB-responsive gene, was enhanced by over 2-fold after 16 h of treatment and remained elevated at 24 h. During this period of time, no changes in cell cycle distribution were observed. To assess changes in the expression levels of NFkappaB-responsive genes as a function of WR-1065 exposure, cDNA arrays containing 49 genes identified as having DNA-binding motifs for NFkappaB were used. Only five genes were found to be significantly affected at 1, 4, and/or 16 h of treatment. GST-3 and c-myc were repressed up to 2- and 4-fold, respectively. The expression levels of IL-2Ra, RANTES, and c-myb, in contrast, were enhanced up to 14-, 3-, and 2-fold, respectively. The remaining genes having NFkappaB-responsive elements in their promoter regions were either not expressed (20 genes) or were not affected (24 genes) by exposure to WR-1065. CONCLUSIONS The redox-sensitive transcription factor NFkappaB can be activated in U87 glioma cells by the active thiol form of the cytoprotector amifostine. Activation of NFkappaB by the antioxidant WR-1065 is accompanied by a reduced expression of the oncogene c-myc and an enhanced expression of the antioxidant gene MnSOD, a gene whose expression in tumor cells is relatively low, but when overexpressed has been correlated with a suppression of the malignant phenotype. Activation of NFkappaB by WR-1065, however, results in selective rather than global changes in the expression of genes containing NFkappaB-responsive elements.
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Affiliation(s)
- Yasushi Kataoka
- Department of Radiation and Cellular Oncology, University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
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18
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Shin DH, Lee HW, Jeon GS, Lee HY, Lee KH, Cho SS. Constitutive expression of c-myb mRNA in the adult rat brain. Brain Res 2001; 892:203-7. [PMID: 11172765 DOI: 10.1016/s0006-8993(00)03300-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In this study, we demonstrated the c-myb mRNA expression in the adult rat brain using an in situ hybridization technique. We found c-myb mRNA signals in the various regions of the forebrain and midbrain including the cerebral cortex, thalamus, hippocampus, hypothalamus, superior and inferior colliculi and central gray. In the cerebellum, a diffuse signal was found in the granular layer while some positive cells were detected in the molecular layer as well. In addition, a number of cells showed intense signals in many nuclei of the medulla oblongata. The constitutive expression of c-myb mRNA in the different kinds of neural cells suggests that this gene might be involved in the normal function of these neurons.
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Affiliation(s)
- D H Shin
- Department of Anatomy, Dankook University College of Medicine, Chonan, South Korea
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19
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The molecular genetics of astrocytomas: current understanding and future applications. J Clin Neurosci 1997; 4:114-21. [DOI: 10.1016/s0967-5868(97)90060-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/1995] [Accepted: 03/05/1996] [Indexed: 11/21/2022]
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Abstract
The poor prognosis associated with malignant primary brain tumors has led investigators to seek and develop new, innovative treatment modalities. Current adjuvant therapies lack tumor specificity, which can lead to toxic central nervous system side effects. Advances in molecular biology now allow specific gene sequences to be inserted or targeted in the malignant cell genome. Antisense oligodeoxynucleotides represent complementary nucleic acid sequences that can recognize and bind to target genes, resulting in the arrest of deoxyribonucleic acid transcription or the translation of messenger ribonucleic acid. Although the use of antisense oligodeoxynucleotides is still in the experimental stages, these molecules enter cells in tissue culture by simple diffusion or active endocytosis and temporarily inhibit cell proliferation in a time- and dose-dependent fashion. The ability of antisense oligodeoxynucleotides to recognize specific gene sequences and to down-regulate gene expression make them ideal agents for use in targeting oncogenes, such as c-myb, that are expressed in central nervous system neoplasms.
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Affiliation(s)
- W A Hall
- Department of Neurosurgery, University of Minnesota Hospital and Clinic, Minneapolis, USA
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21
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Abstract
Ependymomas, which comprise 5% of central nervous system tumors, have not been extensively characterized genetically. The p53 tumor suppressor gene is frequently mutated in human cancer, and is important in the pathogenesis of other central nervous system (CNS) tumors. Chromosomal DNA corresponding to the p53 tumor suppressor gene was amplified by the polymerase chain reaction (PCR) from 31 archival ependymoma specimens. DNA was screened for the presence of p53 mutations by single strand conformational polymorphism (SSCP) analysis; samples with altered mobility were further tested for the presence of mutation by direct DNA sequence analysis. Of the 31 ependymomas tested, one contained a detectable DNA sequence change in the p53 gene. Sequencing revealed a silent mutation in exon 6, at codon 213, which represents a known p53 sequence polymorphism. These finding suggest that in contrast to many other human cancers, p53 mutation is not important in the pathogenesis or progression of ependymomas.
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Affiliation(s)
- K L Fink
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, USA
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22
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Abstract
Gliomas represent the largest group of primary brain tumors in adults. The astrocytic variants are the most common and the adult forms are histologically stratified into three malignancy grades. Of these glioblastoma is the most common and the most malignant; it has also been best studied by molecular genetics and cytogenetics. Double-minute chromosomes, known to represent amplified genes, are found in 50% of glioblastomas. Amplified genes are not detected in the most benign of the astrocytomas. Many genes have been shown to be amplified in more than single cases of gliomas and these include EGFR, CDK4, SAS, MDM2, GLI, PDGFAR, MYC, N MYC, MYCL1, MET, GADD153, and KIT. The most commonly amplified genes in glioblastomas are EGFR (in approximately 40%), CDK4, and SAS (in approximately 15%). The remainder of the genes are amplified at lower frequency. The best mapped amplicon in gliomas involves the 12q13-14 region. The amplicon is of undetermined size, encompasses a number of genes, and may be rearranged. It occurs in 15% of glioblastomas and almost always includes the CDK4 and SAS genes, in about 10% of tumors the MDM2 gene, and at lower frequency GLI, GADD153, and A2MR. All but A2MR are overexpressed if amplified. The amplified EGFR gene is frequently rearranged, resulting in changes in the regions of the transcript that codes for the extracellular domain. The resultant receptor is constitutively activated. These findings provide examples of the impact the use of modern molecular biological techniques has had on our understanding of oncogenic mechanisms in gliomas.
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Affiliation(s)
- V P Collins
- Institute for Oncology and Pathology, Karolinska Institute, Stockholm, Sweden
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23
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Amariglio N, Friedman E, Mor O, Stiebel H, Phelan C, Collins P, Nordenskjold M, Brok-Simoni F, Rechavi G. Analysis of microsatellite repeats in pediatric brain tumors. CANCER GENETICS AND CYTOGENETICS 1995; 84:56-9. [PMID: 7497444 DOI: 10.1016/0165-4608(95)00085-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Tumorigenesis has been shown to proceed through a series of genetic alterations involving protooncogenes and tumor suppressor genes. However, investigation of genomic instability of microsatellites has disclosed a new mechanism for human carcinogenesis, which is involved not only in hereditary nonpolyposis colon cancer (HNPCC) but also in a number of other malignancies. To determine whether microsatellite instability is involved in pediatric brain tumors, we screened 15 such tumors using seven microsatellite marker loci on six chromosomes 4, 5, 9p, 9q, 11, 14, and 17. Using the polymerase chain reaction method, DNA samples from the tumors and from normal peripheral blood leukocytes from each patient were compared for the allelic pattern produced at each locus. Our preliminary results indicate loss of heterozygosity at the fatty acid binding protein (FABP) locus, located on chromosomal arm 4q28-q31, the only trinucleotide repeat in the panel of markers used, for 3 of 15 cases, suggesting the presence of previously unidentified sequences relevant to brain tumorigenesis at or in the vicinity of this locus. We did not observe any microsatellite instability in these samples, indicating that the mechanisms operating in HNPCC are not active in this subset of pediatric brain tumors.
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Affiliation(s)
- N Amariglio
- Institute of Hematology, Sheba Medical Center, Tel Hashomer, Israel
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24
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Hirvonen HE, Salonen R, Sandberg MM, Vuorio E, Västrik I, Kotilainen E, Kalimo H. Differential expression of myc, max and RB1 genes in human gliomas and glioma cell lines. Br J Cancer 1994; 69:16-25. [PMID: 8286200 PMCID: PMC1968776 DOI: 10.1038/bjc.1994.3] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Deregulated expression of myc proto-oncogenes is implicated in several human neoplasias. We analysed the expression of c-myc, N-myc, L-myc, max and RB1 mRNAs in a panel of human gliomas and glioma cell lines and compared the findings with normal neural cells. The max and RB1 genes were included in the study because their protein products can interact with the Myc proteins, being thus putative modulators of Myc activity. Several gliomas contained c/L-myc mRNAs at levels higher than those in fetal brain, L-myc predominantly in grade II/III and c-myc in grade III gliomas. High-level N-myc expression was detected. In one small-cell glioblastoma and lower levels in five other gliomas. In contrast, glioma cell lines totally lacked N/L-myc expression. The in situ hybridisations revealed mutually exclusive topographic distribution of myc and glial fibrillary acidic protein (GFAP) mRNAs, and a lack of correlation between myc expression and proliferative activity, max and RB1 mRNAs were detected in most tumours and cell lines. The glioma cells displayed interesting alternative splicing patterns of max mRNAs encoding Max proteins which either suppress (Max) or augment (delta Max) the transforming activity of Myc. We conclude that (1) glioma cells in vivo may coexpress several myc genes, thus resembling fetal neural cells; but (2) cultured glioma cells expression only c-myc; (3) myc, max and RB1 are regulated independently in glioma cells; and (4) alternative processing of max mRNA in some glioma cells results in delta Max encoding mRNAs not seen in normal fetal brain.
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Affiliation(s)
- H E Hirvonen
- Department of Medical Biochemistry, University of Turku, Finland
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25
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Collins VP. Epidermal growth factor receptor gene and its transcripts in glioblastomas. Recent Results Cancer Res 1994; 135:17-24. [PMID: 8047691 DOI: 10.1007/978-3-642-85039-4_3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- V P Collins
- Department of Pathology, Sahlgrenska Hospital, Gothenburg, Sweden
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26
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Abstract
Significant advances have recently been made in a number of areas concerning central nervous system (CNS) neoplasia. Particularly salient are the following: (1) gene amplification is related to increasing grade of human glioma malignancy and occurs in approximately 40% of the most common and most malignant variety of glioma, glioblastoma multiforme (GBM), (2) by far the most commonly amplified gene in glioblastomas is the epidermal growth factor receptor (EGFR) gene, which is amplified in about one third of GBMs, (3) a small percentage of GBMs amplify N-myc or the novel sequence gli, (4) the EGFR gene is rearranged in at least half of gliomas in which it is amplified, and (5) EGFR gene rearrangement results in external domain deletions that yield truncated EGF receptors. Antibodies specific for the mutant EGF receptor fusion junction have been successfully produced and provide stimulating new potential avenues for tumor imaging and therapy. For pediatric CNS neoplasms, only medulloblastoma has been investigated in adequate numbers; a small percentage exhibit amplification of either the N-myc or c-myc genes.
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Affiliation(s)
- G N Fuller
- Department of Pathology, Duke University Medical Center, Durham, NC 27710
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