1
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Brandner S. Rodent models of tumours of the central nervous system. Mol Oncol 2024. [PMID: 39324445 DOI: 10.1002/1878-0261.13729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 07/03/2024] [Accepted: 08/23/2024] [Indexed: 09/27/2024] Open
Abstract
Modelling of human diseases is an essential component of biomedical research, to understand their pathogenesis and ultimately, develop therapeutic approaches. Here, we will describe models of tumours of the central nervous system, with focus on intrinsic CNS tumours. Model systems for brain tumours were established as early as the 1920s, using chemical carcinogenesis, and a systematic analysis of different carcinogens, with a more refined histological analysis followed in the 1950s and 1960s. Alternative approaches at the time used retroviral carcinogenesis, allowing a more topical, organ-centred delivery. Most of the neoplasms arising from this approach were high-grade gliomas. Whilst these experimental approaches did not directly demonstrate a cell of origin, the localisation and growth pattern of the tumours already pointed to an origin in the neurogenic zones of the brain. In the 1980s, expression of oncogenes in transgenic models allowed a more targeted approach by expressing the transgene under tissue-specific promoters, whilst the constitutive inactivation of tumour suppressor genes ('knock out')-often resulted in embryonic lethality. This limitation was elegantly solved by engineering the Cre-lox system, allowing for a promoter-specific, and often also time-controlled gene inactivation. More recently, the use of the CRISPR Cas9 technology has significantly increased experimental flexibility of gene expression or gene inactivation and thus added increased value of rodent models for the study of pathogenesis and establishing preclinical models.
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Affiliation(s)
- Sebastian Brandner
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology and Division of Neuropathology, The National Hospital for Neurology and Neurosurgery, University College London Hospitals, NHS Foundation Trust, London, UK
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2
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Yvone GM, Breunig JJ. Pediatric low-grade glioma models: advances and ongoing challenges. Front Oncol 2024; 13:1346949. [PMID: 38318325 PMCID: PMC10839015 DOI: 10.3389/fonc.2023.1346949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 12/29/2023] [Indexed: 02/07/2024] Open
Abstract
Pediatric low-grade gliomas represent the most common childhood brain tumor class. While often curable, some tumors fail to respond and even successful treatments can have life-long side effects. Many clinical trials are underway for pediatric low-grade gliomas. However, these trials are expensive and challenging to organize due to the heterogeneity of patients and subtypes. Advances in sequencing technologies are helping to mitigate this by revealing the molecular landscapes of mutations in pediatric low-grade glioma. Functionalizing these mutations in the form of preclinical models is the next step in both understanding the disease mechanisms as well as for testing therapeutics. However, such models are often more difficult to generate due to their less proliferative nature, and the heterogeneity of tumor microenvironments, cell(s)-of-origin, and genetic alterations. In this review, we discuss the molecular and genetic alterations and the various preclinical models generated for the different types of pediatric low-grade gliomas. We examined the different preclinical models for pediatric low-grade gliomas, summarizing the scientific advances made to the field and therapeutic implications. We also discuss the advantages and limitations of the various models. This review highlights the importance of preclinical models for pediatric low-grade gliomas while noting the challenges and future directions of these models to improve therapeutic outcomes of pediatric low-grade gliomas.
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Affiliation(s)
- Griselda Metta Yvone
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Joshua J. Breunig
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Center for Neural Sciences in Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
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3
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Xing YL, Panovska D, Petritsch CK. Successes and challenges in modeling heterogeneous BRAF V600E mutated central nervous system neoplasms. Front Oncol 2023; 13:1223199. [PMID: 37920169 PMCID: PMC10619673 DOI: 10.3389/fonc.2023.1223199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 09/18/2023] [Indexed: 11/04/2023] Open
Abstract
Central nervous system (CNS) neoplasms are difficult to treat due to their sensitive location. Over the past two decades, the availability of patient tumor materials facilitated large scale genomic and epigenomic profiling studies, which have resulted in detailed insights into the molecular underpinnings of CNS tumorigenesis. Based on results from these studies, CNS tumors have high molecular and cellular intra-tumoral and inter-tumoral heterogeneity. CNS cancer models have yet to reflect the broad diversity of CNS tumors and patients and the lack of such faithful cancer models represents a major bottleneck to urgently needed innovations in CNS cancer treatment. Pediatric cancer model development is lagging behind adult tumor model development, which is why we focus this review on CNS tumors mutated for BRAFV600E which are more prevalent in the pediatric patient population. BRAFV600E-mutated CNS tumors exhibit high inter-tumoral heterogeneity, encompassing clinically and histopathological diverse tumor types. Moreover, BRAFV600E is the second most common alteration in pediatric low-grade CNS tumors, and low-grade tumors are notoriously difficult to recapitulate in vitro and in vivo. Although the mutation predominates in low-grade CNS tumors, when combined with other mutations, most commonly CDKN2A deletion, BRAFV600E-mutated CNS tumors are prone to develop high-grade features, and therefore BRAFV600E-mutated CNS are a paradigm for tumor progression. Here, we describe existing in vitro and in vivo models of BRAFV600E-mutated CNS tumors, including patient-derived cell lines, patient-derived xenografts, syngeneic models, and genetically engineered mouse models, along with their advantages and shortcomings. We discuss which research gaps each model might be best suited to answer, and identify those areas in model development that need to be strengthened further. We highlight areas of potential research focus that will lead to the heightened predictive capacity of preclinical studies, allow for appropriate validation, and ultimately improve the success of "bench to bedside" translational research.
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Affiliation(s)
| | | | - Claudia K. Petritsch
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA, United States
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4
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Ye Q, Srivastava P, Al-Kuwari N, Chen X. Oncogenic BRAFV600E induces microglial proliferation through extracellular signal-regulated kinase and neuronal death through c-Jun N-terminal kinase. Neural Regen Res 2023; 18:1613-1622. [PMID: 36571370 PMCID: PMC10075110 DOI: 10.4103/1673-5374.361516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 06/13/2022] [Accepted: 10/18/2022] [Indexed: 11/19/2022] Open
Abstract
Activating V600E in v-Raf murine sarcoma viral oncogene homolog B (BRAF) is a common driver mutation in cancers of multiple tissue origins, including melanoma and glioma. BRAFV600E has also been implicated in neurodegeneration. The present study aims to characterize BRAFV600E during cell death and proliferation of three major cell types of the central nervous system: neurons, astrocytes, and microglia. Multiple primary cultures (primary cortical mixed culture) and cell lines of glial cells (BV2) and neurons (SH-SY5Y) were employed. BRAFV600E and BRAFWT expression was mediated by lentivirus or retrovirus. Blockage of downstream effectors (extracellular signal-regulated kinase 1/2 and JNK1/2) were achieved by siRNA. In astrocytes and microglia, BRAFV600E induces cell proliferation, and the proliferative effect in microglia is mediated by activated extracellular signal-regulated kinase, but not c-Jun N-terminal kinase. Conditioned medium from BRAFV600E-expressing microglia induced neuronal death. In neuronal cells, BRAFV600E directly induces neuronal death, through c-Jun N-terminal kinase but not extracellular signal-regulated kinase. We further show that BRAF-related genes are enriched in pathways in patients with Parkinson's disease. Our study identifies distinct consequences mediated by distinct downstream effectors in dividing glial cells and in neurons following the same BRAF mutational activation and a causal link between BRAF-activated microglia and neuronal cell death that does not require physical proximity. It provides insight into a possibly important role of BRAF in neurodegeneration as a result of either dysregulated BRAF in neurons or its impact on glial cells.
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Affiliation(s)
- Qing Ye
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
- Department of Neurology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Pranay Srivastava
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
| | - Nasser Al-Kuwari
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Xiqun Chen
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
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5
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Marlow C, Cuoco JA, Hoggarth AR, Stump MS, Apfel LS, Rogers CM. Pediatric diffuse hemispheric glioma H3 G34-mutant with gains of the BRAF locus: An illustrative case. Rare Tumors 2023; 15:20363613231168704. [PMID: 37056711 PMCID: PMC10088409 DOI: 10.1177/20363613231168704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 03/22/2023] [Indexed: 04/15/2023] Open
Abstract
Diffuse hemispheric glioma, H3 G34-mutant, is a recently recognized distinct high-grade glioma with a dismal prognosis. In addition to the H3 G34 missense mutation, numerous genetic events have been identified in these malignant tumors, including ATRX, TP53, and, rarely, BRAF genes. There are only a few reports to date that have identified BRAF mutations in diffuse hemispheric glioma, H3 G34-mutant. Moreover, to our knowledge, gains of the BRAF locus have yet to be described. Here, we present a case of an 11-year-old male with a diffuse hemispheric glioma, H3 G34-mutant, found to have novel gains of the BRAF locus. Furthermore, we emphasize the current genetic landscape of diffuse hemispheric glioma, H3 G34-mutant, and implications of an aberrant BRAF signaling pathway.
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Affiliation(s)
| | - Joshua A Cuoco
- Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
- Section of Neurosurgery, Carilion Clinic, Roanoke, VA, USA
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
- Joshua A Cuoco, Carilion Clinic, Section of Neurosurgery, 2331 Franklin Road, Roanoke 24014, VA, USA.
| | - Austin R Hoggarth
- Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
- Section of Neurosurgery, Carilion Clinic, Roanoke, VA, USA
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Michael S Stump
- Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
- Department of Pathology, Carilion Clinic, Roanoke, VA, USA
| | - Lisa S Apfel
- Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
- Section of Neurosurgery, Carilion Clinic, Roanoke, VA, USA
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Cara M Rogers
- Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
- Section of Neurosurgery, Carilion Clinic, Roanoke, VA, USA
- School of Neuroscience, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
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6
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Jesus-Ribeiro J, Rebelo O, Ribeiro IP, Pires LM, Melo JD, Sales F, Santana I, Freire A, Melo JB. The landscape of common genetic drivers and DNA methylation in low-grade (epilepsy-associated) neuroepithelial tumors: A review. Neuropathology 2022; 42:467-482. [PMID: 35844095 DOI: 10.1111/neup.12846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 05/05/2022] [Accepted: 06/05/2022] [Indexed: 12/15/2022]
Abstract
Low-grade neuroepithelial tumors (LNETs) represent an important group of central nervous system neoplasms, some of which may be associated to epilepsy. The concept of long-term epilepsy-associated tumors (LEATs) includes a heterogenous group of low-grade, cortically based tumors, associated to drug-resistant epilepsy, often requiring surgical treatment. LEATs entities can sometimes be poorly discriminated by histological features, precluding a confident classification in the absence of additional diagnostic tools. This study aimed to provide an updated review on the genomic findings and DNA methylation profiling advances in LNETs, including histological entities of LEATs. A comprehensive search strategy was conducted on PubMed, Embase, and Web of Science Core Collection. High-quality peer-reviewed original manuscripts and review articles with full-text in English, published between 2003 and 2022, were included. Results were screened based on titles and abstracts to determine suitability for inclusion, and when addressed the topic of the review was screened by full-text reading. Data extraction was performed through a qualitative content analysis approach. Most LNETs appear to be driven mainly by a single genomic abnormality and respective affected signaling pathway, including BRAF p.V600E mutations in ganglioglioma, FGFR1 abnormalities in dysembryoplastic neuroepithelial tumor, MYB alterations in angiocentric glioma, BRAF fusions in pilocytic astrocytoma, PRKCA fusions in papillary glioneuronal tumor, between others. However, these molecular alterations are not exclusive, with some overlap amongst different tumor histologies. Also, clustering analysis of DNA methylation profiles allowed the identification of biologically similar molecular groups that sometimes transcend conventional histopathological classification. The exciting developments on the molecular basis of these tumors reinforce the importance of an integrative histopathological and (epi)genetic classification, which can be translated into precision medicine approaches.
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Affiliation(s)
- Joana Jesus-Ribeiro
- Neurology Department, Centro Hospitalar de Leiria, Leiria, Portugal.,Coimbra Institute for Clinical and Biomedical Research (iCBR) and Center of Investigation on Environment Genetics and Oncobiology (CIMAGO), Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Olinda Rebelo
- Neuropathology Laboratory, Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - Ilda Patrícia Ribeiro
- Coimbra Institute for Clinical and Biomedical Research (iCBR) and Center of Investigation on Environment Genetics and Oncobiology (CIMAGO), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,Laboratory of Cytogenetics and Genomics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Luís Miguel Pires
- Coimbra Institute for Clinical and Biomedical Research (iCBR) and Center of Investigation on Environment Genetics and Oncobiology (CIMAGO), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,Laboratory of Cytogenetics and Genomics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - João Daniel Melo
- Internal Medicine Department, CUF Coimbra Hospital, Coimbra, Portugal
| | - Francisco Sales
- Epilepsy and Sleep Monitoring Unit, Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - Isabel Santana
- Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - António Freire
- Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,Neurology Department, Coimbra Luz Hospital, Coimbra, Portugal
| | - Joana Barbosa Melo
- Coimbra Institute for Clinical and Biomedical Research (iCBR) and Center of Investigation on Environment Genetics and Oncobiology (CIMAGO), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,Laboratory of Cytogenetics and Genomics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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7
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Turkez H, Arslan ME, Tatar A, Mardinoglu A. Promising potential of boron compounds against Glioblastoma: In Vitro antioxidant, anti-inflammatory and anticancer studies. Neurochem Int 2021; 149:105137. [PMID: 34293392 DOI: 10.1016/j.neuint.2021.105137] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 07/06/2021] [Accepted: 07/08/2021] [Indexed: 12/20/2022]
Abstract
Glioblastoma (GB) is the most common and aggressive primary malignant astrocytoma correlated with poor patient survival. There are no curative treatments for GB, and it becomes resistant to chemotherapy, radiation therapy, and immunotherapy. Resistance in GB cells is closely related to their states of redox imbalance, and the role of reactive oxygen species and its impact on cancer cell survival is still far from elucidation. Boron-containing compounds, especially boric acid (BA) and borax (BX) exhibited interesting biological effects involving antibacterial, antiviral, anti-cancerogenic, anti-mutagenic, anti-inflammatory as well as anti-oxidative features. Recent studies indicated that certain boron compounds could be cytotoxic on human GB. Nevertheless, there is gap of knowledge in the literature on exploring the underlying mechanisms of anti-GB action by boron compounds. Here, we identified and compared the potential anti-GB effect of both BA and BX, and revealed their underlying anti-GB mechanism. We performed cell viability, oxidative alterations, oxidative DNA damage potential assays, and explored the inflammatory responses and gene expression changes by real-time PCR using U-87MG cells. We found that BA and BX led to a remarkable reduction in U-87MG cell viability in a concentration-dependent manner. We also found that boron compounds increased the total oxidative status and MDA levels along with the SOD and CAT enzyme activities and decreased total antioxidant capacity and GSH levels in U-87MG cells without inducing DNA damage. The cytokine levels of cancer cells were also altered. We verified the selectivity of the compounds using a normal cell line, HaCaT and found an exact opposite condition after treating HaCaT cells with BA and BX. BA applications were more effective than BX on U-87MG cell line in terms of increasing MDA levels, SOD and CAT enzyme activities, and decreasing Interleukin-1α, Interleukin-6 and Tumor necrosis factor- α (TNF- α) levels. We finally observed that anticancer effect of BA and BX were associated with the BRAF/MAPK, PTEN and PI3K/AKT signaling pathways in respect of downregulatory manner. Especially, BA application was found more favorable because of its inhibitory effect on PIK3CA, PIK3R1, PTEN and RAF1 genes. In conclusion, our analysis indicated that boron compounds may be safe and promising for effective treatment of GB.
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Affiliation(s)
- Hasan Turkez
- Department of Medical Biology, Faculty of Medicine, Ataturk University, 25240, Erzurum, Turkey
| | - Mehmet Enes Arslan
- Department of Molecular Biology and Genetics, Faculty of Science, 25250; Erzurum Technical University, Erzurum, Turkey
| | - Abdulgani Tatar
- Department of Medical Genetics, Faculty of Medicine, Ataturk University, 25240; Erzurum, Turkey
| | - Adil Mardinoglu
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, SE1 9RT, UK; Science for Life Laboratory, KTH - Royal Institute of Technology, Stockholm, SE-17121, Sweden.
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8
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Natsumeda M, Kanemaru Y, Kawaguchi Y, Umezu H, Kakita A, Fujii Y. Less-invasive diagnosis of disseminated epithelioid glioblastoma harboring BRAF V600E mutation by cerebrospinal fluid analysis-A case report. Clin Case Rep 2021; 9:e04551. [PMID: 34295500 PMCID: PMC8283864 DOI: 10.1002/ccr3.4551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 05/31/2021] [Accepted: 06/13/2021] [Indexed: 11/11/2022] Open
Abstract
Spinal dissemination in epithelioid glioblastoma can be diagnosed by cerebrospinal fluid cytology and liquid biopsy to detect BRAF V600E mutation.
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Affiliation(s)
- Manabu Natsumeda
- Department of NeurosurgeryBrain Research InstituteNiigata UniversityNiigataJapan
| | - Yu Kanemaru
- Department of NeurosurgeryBrain Research InstituteNiigata UniversityNiigataJapan
| | - Yukie Kawaguchi
- Division of PathologyNiigata University Medical & Dental HospitalNiigataJapan
| | - Hajime Umezu
- Division of PathologyNiigata University Medical & Dental HospitalNiigataJapan
| | - Akiyoshi Kakita
- Department of PathologyBrain Research InstituteNiigata UniversityNiigataJapan
| | - Yukihiko Fujii
- Department of NeurosurgeryBrain Research InstituteNiigata UniversityNiigataJapan
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9
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Wang W, Wang M, Jiang H, Wang T, Da R. BRAF non-V600E more frequently co-occurs with IDH1/2 mutations in adult patients with gliomas than in patients harboring BRAF V600E but without a survival advantage. BMC Neurol 2021; 21:195. [PMID: 33980169 PMCID: PMC8114535 DOI: 10.1186/s12883-021-02224-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 05/05/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The effects of BRAFnon-V600E and BRAFV600E on the outcomes and the molecular characteristics of adult glioma patients are unknown and need to be explored, although BRAFV600E has been extensively studied in pediatric glioma. METHODS Co-occurring mutations and copy number alterations of associated genes in the MAPK and p53 pathways were investigated using data from The Cancer Genome Atlas (TCGA) public database retrieved by cBioPortal. The prognosis of available adult glioma cohorts with BRAFV600E and BRAFnon-V600E mutations were also investigated. RESULTS Ninety patients with BRAFV600E or BRAFnon-V600E were enrolled in this study, and data from 52 nonredundant patients were investigated. Glioblastoma multiform was the most common cancer type, with BRAF non-V600E and BRAFV600E. TP53 (56.00% vs. 7.41%), IDH1/2 (36.00% vs. 3.70%), and ATRX (32.00% vs. 7.41%) exhibited more mutations in BRAFnon-V600E than in BRAFV600E, and TP53 was an independent risk factor (56.00% vs. 7.41%). Both BRAFnon-V600E and BRAFV600E frequently overlapped with CDKN2A/2B homozygous deletions (HDs), but there was no significant difference. Survival analysis showed no difference between the BRAF non-V600E and BRAFV600E cohorts, even after excluding the survival benefit of IDH1/2 mutations and considering the BRAFnon-V600E mutations in the glycine-rich loop (G-loop) and in the activation segment. The estimated mean survival of patients with BRAFnon-V600E & IDH1/2WT with mutations in the G-loop groups was the shortest. CONCLUSIONS BRAFnon-V600E exhibited a stronger association with IDH1/2 mutations than BRAFV600E, but no survival advantage was found.
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Affiliation(s)
- Wei Wang
- Department of Neurosurgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Maode Wang
- Department of Neurosurgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Haitao Jiang
- Department of Neurosurgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Tuo Wang
- Department of Neurosurgery, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Rong Da
- Department of Clinical Laboratory, The First Affiliated Hospital of Xi'an Jiaotong University, No.277 Yanta West Road, Xi'an, 710061, Shaanxi, China.
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10
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Hypothalamic Rax + tanycytes contribute to tissue repair and tumorigenesis upon oncogene activation in mice. Nat Commun 2021; 12:2288. [PMID: 33863883 PMCID: PMC8052410 DOI: 10.1038/s41467-021-22640-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/22/2021] [Indexed: 11/24/2022] Open
Abstract
Hypothalamic tanycytes in median eminence (ME) are emerging as a crucial cell population that regulates endocrine output, energy balance and the diffusion of blood-born molecules. Tanycytes have recently been considered as potential somatic stem cells in the adult mammalian brain, but their regenerative and tumorigenic capacities are largely unknown. Here we found that Rax+ tanycytes in ME of mice are largely quiescent but quickly enter the cell cycle upon neural injury for self-renewal and regeneration. Mechanistically, Igf1r signaling in tanycytes is required for tissue repair under injury conditions. Furthermore, Braf oncogenic activation is sufficient to transform Rax+ tanycytes into actively dividing tumor cells that eventually develop into a papillary craniopharyngioma-like tumor. Together, these findings uncover the regenerative and tumorigenic potential of tanycytes. Our study offers insights into the properties of tanycytes, which may help to manipulate tanycyte biology for regulating hypothalamic function and investigate the pathogenesis of clinically relevant tumors. Tanycytes contribute to the regulation of multiple hypothalamic functions. Here the authors investigate the regenerative and tumorigenic potential of adult Rax+ tanycytes in the median eminence in the context of the stem cell niche in mice.
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11
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Kanvinde PP, Malla AP, Connolly NP, Szulzewsky F, Anastasiadis P, Ames HM, Kim AJ, Winkles JA, Holland EC, Woodworth GF. Leveraging the replication-competent avian-like sarcoma virus/tumor virus receptor-A system for modeling human gliomas. Glia 2021; 69:2059-2076. [PMID: 33638562 PMCID: PMC8591561 DOI: 10.1002/glia.23984] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 12/20/2022]
Abstract
Gliomas are the most common primary intrinsic brain tumors occurring in adults. Of all malignant gliomas, glioblastoma (GBM) is considered the deadliest tumor type due to diffuse brain invasion, immune evasion, cellular, and molecular heterogeneity, and resistance to treatments resulting in high rates of recurrence. An extensive understanding of the genomic and microenvironmental landscape of gliomas gathered over the past decade has renewed interest in pursuing novel therapeutics, including immune checkpoint inhibitors, glioma-associated macrophage/microglia (GAMs) modulators, and others. In light of this, predictive animal models that closely recreate the conditions and findings found in human gliomas will serve an increasingly important role in identifying new, effective therapeutic strategies. Although numerous syngeneic, xenograft, and transgenic rodent models have been developed, few include the full complement of pathobiological features found in human tumors, and therefore few accurately predict bench-to-bedside success. This review provides an update on how genetically engineered rodent models based on the replication-competent avian-like sarcoma (RCAS) virus/tumor virus receptor-A (tv-a) system have been used to recapitulate key elements of human gliomas in an immunologically intact host microenvironment and highlights new approaches using this model system as a predictive tool for advancing translational glioma research.
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Affiliation(s)
- Pranjali P Kanvinde
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Adarsha P Malla
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Nina P Connolly
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Frank Szulzewsky
- Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Pavlos Anastasiadis
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Heather M Ames
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Department of Pathology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Anthony J Kim
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Jeffrey A Winkles
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Eric C Holland
- Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,Seattle Tumor Translational Research Center, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Graeme F Woodworth
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
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12
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Clinical Relevance of BRAF V600E Mutation Status in Brain Tumors with a Focus on a Novel Management Algorithm. Target Oncol 2020; 15:531-540. [PMID: 32648041 PMCID: PMC7434793 DOI: 10.1007/s11523-020-00735-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The possible application of BRAF-targeted therapy in brain tumors is growing continuously. We have analyzed clinical strategies that address BRAF activation in primary brain tumors and verified current recommendations regarding screening for BRAF mutations. There is preliminary evidence for a range of positive responses in certain brain tumor types harboring the BRAF V600E mutation. National Comprehensive Cancer Network Guidelines for central nervous system cancers recommend screening for the BRAF V600E mutation in pilocytic astrocytoma, pleomorphic xanthoastrocytoma, and ganglioglioma. We suggest additional testing in glioblastomas WHO grade IV below the age of 30 years, especially those with epithelioid features, papillary craniopharyngiomas, and pediatric low-grade astrocytomas. BRAF-targeted therapy should be limited to the setting of a clinical trial. If the patient harboring a V600E mutation does not qualify for a trial, multimodality treatment is recommended. Dual inhibition of both RAF and MEK is expected to provide more potent and durable effects than anti-BRAF monotherapy. First-generation RAF inhibitors should be avoided. Gain-of-function mutations of EGFR and KIAA fusions may compromise BRAF-targeted therapy. BRAF alterations that result in MAPK pathway activation are common events in several types of brain tumors. BRAF V600E mutation emerges as a promising molecular target. The proposed algorithm was designed to help oncologists to provide the best therapeutic options for brain tumor patients.
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13
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Grigore F, Yang H, Hanson ND, VanBrocklin MW, Sarver AL, Robinson JP. BRAF inhibition in melanoma is associated with the dysregulation of histone methylation and histone methyltransferases. Neoplasia 2020; 22:376-389. [PMID: 32629178 PMCID: PMC7338995 DOI: 10.1016/j.neo.2020.06.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/05/2020] [Accepted: 06/08/2020] [Indexed: 12/24/2022] Open
Abstract
The development of mutant BRAF inhibitors has improved the outcome for melanoma patients with BRAFV600E mutations. Although the initial response to these inhibitors can be dramatic, sometimes resulting in complete tumor regression, the majority of melanomas become resistant. To study resistance to BRAF inhibition, we developed a novel mouse model of melanoma using a tetracycline/doxycycline-regulated system that permits control of mutant BRAF expression. Treatment with doxycycline leads to loss of mutant BRAF expression and tumor regression, but tumors recur after a prolonged period of response to treatment. Vemurafenib, encorafenib and dabrafenib induce cell cycle arrest and apoptosis in BRAF melanoma cell lines; however, a residual population of tumor cells survive. Comparing gene expression in human cell lines and mouse tumors can assist with the identification of novel mechanisms of resistance. Accordingly, we conducted RNA sequencing analysis and immunoblotting on untreated and doxycycline-treated dormant mouse melanomas and human mutant BRAF melanoma cell lines treated with 2 μM vemurafenib for 20 days. We found conserved expression changes in histone methyltransferase genes ASH2, EZH2, PRMT5, SUV39H1, SUV39H2, and SYMD2 in P-ERK low, p-38 high melanoma cells following prolonged BRAF inhibition. Quantitative mass spectrometry, determined a corresponding reduction in histone Lys9 and Lys27 methylation and increase in Lys36 methylation in melanoma cell lines treated with 2 μM vemurafenib for 20 days. Thus, these changes as are part of the initiate response to BRAF inhibition and likely contribute to the survival of melanoma cells.
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Affiliation(s)
- Florina Grigore
- The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA
| | - Hana Yang
- The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA
| | - Nicholas D Hanson
- The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA
| | - Matthew W VanBrocklin
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA; Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA; Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, Utah 84112, USA
| | - Aaron L Sarver
- Masonic Cancer Center, 2231 6th St SE, Minneapolis, MN 5545, USA; Institute for Health Informatics, 420 Delaware St. SE, Minneapolis, MN 55455, USA
| | - James P Robinson
- The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA; Masonic Cancer Center, 2231 6th St SE, Minneapolis, MN 5545, USA.
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14
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Philip B, Yu DX, Silvis MR, Shin CH, Robinson JP, Robinson GL, Welker AE, Angel SN, Tripp SR, Sonnen JA, VanBrocklin MW, Gibbons RJ, Looper RE, Colman H, Holmen SL. Mutant IDH1 Promotes Glioma Formation In Vivo. Cell Rep 2019; 23:1553-1564. [PMID: 29719265 PMCID: PMC6032974 DOI: 10.1016/j.celrep.2018.03.133] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 02/23/2018] [Accepted: 03/29/2018] [Indexed: 02/08/2023] Open
Abstract
Isocitrate dehydrogenase 1 (IDH1) is the most commonly mutated gene in grade II–III glioma and secondary glioblastoma (GBM). A causal role for IDH1R132H in gliomagenesis has been proposed, but functional validation in vivo has not been demonstrated. In this study, we assessed the role of IDH1R132H in glioma development in the context of clinically relevant cooperating genetic alterations in vitro and in vivo. Immortal astrocytes expressing IDH1R132H exhibited elevated (R)-2-hydroxyglutarate levels, reduced NADPH, increased proliferation, and anchorage-independent growth. Although not sufficient on its own, IDH1R132H cooperated with PDGFA and loss of Cdkn2a, Atrx, and Pten to promote glioma development in vivo. These tumors resembled pro-neural human mutant IDH1 GBM genetically, histologically, and functionally. Our findings support the hypothesis that IDH1R132H promotes glioma development. This model enhances our understanding of the biology of IDH1R132H-driven gliomas and facilitates testing of therapeutic strategies designed to combat this deadly disease.
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Affiliation(s)
- Beatrice Philip
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Diana X Yu
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Mark R Silvis
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Clifford H Shin
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - James P Robinson
- Hormel Institute, University of Minnesota, 801 16(th) Avenue NE, Austin, MN 55912, USA
| | - Gemma L Robinson
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Adam E Welker
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Stephanie N Angel
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Sheryl R Tripp
- ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT 84108, USA
| | - Joshua A Sonnen
- ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT 84108, USA; Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Matthew W VanBrocklin
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Richard J Gibbons
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Ryan E Looper
- Department of Chemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - Howard Colman
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Neurosurgery, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA
| | - Sheri L Holmen
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA.
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15
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Daniel PM, Filiz G, Brown DV, Christie M, Waring PM, Zhang Y, Haynes JM, Pouton C, Flanagan D, Vincan E, Johns TG, Montgomery K, Phillips WA, Mantamadiotis T. PI3K activation in neural stem cells drives tumorigenesis which can be ameliorated by targeting the cAMP response element binding protein. Neuro Oncol 2019; 20:1344-1355. [PMID: 29718345 DOI: 10.1093/neuonc/noy068] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Background Hyperactivation of phosphoinositide 3-kinase (PI3K) signaling is common in cancers, but the precise role of the pathway in glioma biology remains to be determined. Some understanding of PI3K signaling mechanisms in brain cancer comes from studies on neural stem/progenitor cells (NSPCs), where signals transmitted via the PI3K pathway cooperate with other intracellular pathways and downstream transcription factors to regulate critical cell functions. Methods To investigate the role of the PI3K pathway in glioma initiation and development, we generated a mouse model targeting the inducible expression of a PIK3CAH1047A oncogenic mutant and deletion of the PI3K negative regulator, phosphatase and tensin homolog (PTEN), to NSPCs. Results Expression of a Pik3caH1047A was sufficient to generate tumors with oligodendroglial features, but simultaneous loss of PTEN was required for the development of invasive, high-grade glioma. Pik3caH1047A-PTEN mutant NSPCs exhibited enhanced neurosphere formation which correlated with increased Wnt signaling, while loss of cAMP response element binding protein (CREB) in Pik3caH1047A-Pten mutant tumors led to longer symptom-free survival in mice. Conclusion Taken together, our findings present a novel mouse model for glioma demonstrating that the PI3K pathway is important for initiation of tumorigenesis and that disruption of downstream CREB signaling attenuates tumor expansion.
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Affiliation(s)
- Paul M Daniel
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - Gulay Filiz
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - Daniel V Brown
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - Michael Christie
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - Paul M Waring
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - Yi Zhang
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - John M Haynes
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Colin Pouton
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Dustin Flanagan
- Molecular Oncology Laboratory, The University of Melbourne, Parkville, Victoria, Australia
| | - Elizabeth Vincan
- Molecular Oncology Laboratory, The University of Melbourne, Parkville, Victoria, Australia.,Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute, Melbourne, Victoria, Australia.,School of Biomedical Sciences, Curtin University, Perth, Western Australia, Australia
| | - Terrance G Johns
- Oncogenic Signalling Laboratory, Telethon Kids Institute, Subiaco, Western Australia, Australia
| | - Karen Montgomery
- Cancer Biology and Surgical Oncology Research Laboratory, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
| | - Wayne A Phillips
- Cancer Biology and Surgical Oncology Research Laboratory, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Theo Mantamadiotis
- Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia.,Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia.,Department of Surgery (Royal Melbourne Hospital), The University of Melbourne, Parkville, Victoria, Australia
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16
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Weinberg F, Griffin R, Fröhlich M, Heining C, Braun S, Spohr C, Iconomou M, Hollek V, Röring M, Horak P, Kreutzfeldt S, Warsow G, Hutter B, Uhrig S, Neumann O, Reuss D, Heiland DH, von Kalle C, Weichert W, Stenzinger A, Brors B, Glimm H, Fröhling S, Brummer T. Identification and characterization of a BRAF fusion oncoprotein with retained autoinhibitory domains. Oncogene 2019; 39:814-832. [PMID: 31558800 DOI: 10.1038/s41388-019-1021-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 09/09/2019] [Accepted: 09/11/2019] [Indexed: 12/14/2022]
Abstract
Fusion proteins involving the BRAF serine/threonine kinase occur in many cancers. The oncogenic potential of BRAF fusions has been attributed to the loss of critical N-terminal domains that mediate BRAF autoinhibition. We used whole-exome and RNA sequencing in a patient with glioblastoma multiforme to identify a rearrangement between TTYH3, encoding a membrane-resident, calcium-activated chloride channel, and BRAF intron 1, resulting in a TTYH3-BRAF fusion protein that retained all features essential for BRAF autoinhibition. Accordingly, the BRAF moiety of the fusion protein alone, which represents full-length BRAF without the amino acids encoded by exon 1 (BRAFΔE1), did not induce MEK/ERK phosphorylation or transformation. Likewise, neither the TTYH3 moiety of the fusion protein nor full-length TTYH3 provoked ERK pathway activity or transformation. In contrast, TTYH3-BRAF displayed increased MEK phosphorylation potential and transforming activity, which were caused by TTYH3-mediated tethering of near-full-length BRAF to the (endo)membrane system. Consistent with this mechanism, a synthetic approach, in which BRAFΔE1 was tethered to the membrane by fusing it to the cytoplasmic tail of CD8 also induced transformation. Furthermore, we demonstrate that TTYH3-BRAF signals largely independent of a functional RAS binding domain, but requires an intact BRAF dimer interface and activation loop phosphorylation sites. Cells expressing TTYH3-BRAF exhibited increased MEK/ERK signaling, which was blocked by clinically achievable concentrations of sorafenib, trametinib, and the paradox breaker PLX8394. These data provide the first example of a fully autoinhibited BRAF protein whose oncogenic potential is dictated by a distinct fusion partner and not by a structural change in BRAF itself.
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Affiliation(s)
- Florian Weinberg
- Institute of Molecular Medicine and Cell Research, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Centre for Biological Signalling Studies BIOSS, University of Freiburg, Freiburg, Germany
| | - Ricarda Griffin
- Institute of Molecular Medicine and Cell Research, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Martina Fröhlich
- Division of Applied Bioinformatics, German Cancer Research Center (DKFZ) and National Center for Tumor Diseases (NCT) Heidelberg, Heidelberg, Germany
| | - Christoph Heining
- Department of Translational Medical Oncology, NCT Dresden, Dresden, and DKFZ, Heidelberg, Germany.,University Hospital Carl Gustav Carus, Technical University Dresden, Dresden, Germany.,German Cancer Consortium (DKTK), Dresden, Germany
| | - Sandra Braun
- Institute of Molecular Medicine and Cell Research, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Centre for Biological Signalling Studies BIOSS, University of Freiburg, Freiburg, Germany
| | - Corinna Spohr
- Institute of Molecular Medicine and Cell Research, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany.,Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg, Germany
| | - Mary Iconomou
- Institute of Molecular Medicine and Cell Research, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Viola Hollek
- Institute of Molecular Medicine and Cell Research, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Michael Röring
- Institute of Molecular Medicine and Cell Research, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Peter Horak
- Department of Translational Medical Oncology, NCT Heidelberg and DKFZ, Heidelberg, Germany.,DKTK, Heidelberg, Germany
| | - Simon Kreutzfeldt
- Department of Translational Medical Oncology, NCT Heidelberg and DKFZ, Heidelberg, Germany.,DKTK, Heidelberg, Germany
| | - Gregor Warsow
- Omics IT and Data Management Core Facility, DKFZ, Heidelberg, Germany.,Division of Theoretical Bioinformatics, DKFZ, Heidelberg, Germany
| | - Barbara Hutter
- Division of Applied Bioinformatics, German Cancer Research Center (DKFZ) and National Center for Tumor Diseases (NCT) Heidelberg, Heidelberg, Germany
| | - Sebastian Uhrig
- Division of Applied Bioinformatics, German Cancer Research Center (DKFZ) and National Center for Tumor Diseases (NCT) Heidelberg, Heidelberg, Germany.,Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Olaf Neumann
- DKTK, Heidelberg, Germany.,Institute of Pathology, Heidelberg University Hospital, Heidelberg, Germany
| | - David Reuss
- DKTK, Heidelberg, Germany.,Department of Neuropathology, Institute of Pathology, Heidelberg University Hospital, Heidelberg, Germany.,Clinical Cooperation Unit Neuropathology, German Cancer Research Center (DKFZ), German Consortium for Translational Cancer Research (DKTK), Heidelberg, Germany
| | - Dieter Henrik Heiland
- Department of Neurosurgery, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Translational NeuroOncology Research Group, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christof von Kalle
- Department of Translational Oncology, NCT Heidelberg and DKFZ, Heidelberg, Germany
| | - Wilko Weichert
- Institute of Pathology, Technical University Munich, Munich, Germany.,DKTK, Munich, Germany
| | - Albrecht Stenzinger
- DKTK, Heidelberg, Germany.,Institute of Pathology, Heidelberg University Hospital, Heidelberg, Germany
| | - Benedikt Brors
- Division of Applied Bioinformatics, German Cancer Research Center (DKFZ) and National Center for Tumor Diseases (NCT) Heidelberg, Heidelberg, Germany.,DKTK, Heidelberg, Germany
| | - Hanno Glimm
- Department of Translational Medical Oncology, NCT Dresden, Dresden, and DKFZ, Heidelberg, Germany.,University Hospital Carl Gustav Carus, Technical University Dresden, Dresden, Germany.,German Cancer Consortium (DKTK), Dresden, Germany
| | - Stefan Fröhling
- Department of Translational Medical Oncology, NCT Heidelberg and DKFZ, Heidelberg, Germany. .,DKTK, Heidelberg, Germany.
| | - Tilman Brummer
- Institute of Molecular Medicine and Cell Research, Faculty of Medicine, University of Freiburg, Freiburg, Germany. .,Centre for Biological Signalling Studies BIOSS, University of Freiburg, Freiburg, Germany. .,Comprehensive Cancer Centre Freiburg, University of Freiburg, Freiburg, Germany. .,DKTK Partner Site Freiburg and DKFZ, Heidelberg, Germany.
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17
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Kanemaru Y, Natsumeda M, Okada M, Saito R, Kobayashi D, Eda T, Watanabe J, Saito S, Tsukamoto Y, Oishi M, Saito H, Nagahashi M, Sasaki T, Hashizume R, Aoyama H, Wakai T, Kakita A, Fujii Y. Dramatic response of BRAF V600E-mutant epithelioid glioblastoma to combination therapy with BRAF and MEK inhibitor: establishment and xenograft of a cell line to predict clinical efficacy. Acta Neuropathol Commun 2019; 7:119. [PMID: 31345255 PMCID: PMC6659204 DOI: 10.1186/s40478-019-0774-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Accepted: 07/18/2019] [Indexed: 11/14/2022] Open
Abstract
Epithelioid glioblastoma is a rare aggressive variant of glioblastoma (GBM) characterized by a dismal prognosis of about 6 months and frequent leptomeningeal dissemination. A recent study has revealed that 50% of epithelioid GBMs harbor three genetic alterations - BRAF V600E mutation, TERT promoter mutations, and homozygous deletions of CDKN2A/2B. Emerging evidence support the effectiveness of targeted therapies for brain tumors with BRAF V600E mutation. Here we describe a dramatic radiographical response to combined therapy with BRAF and MEK inhibitors in a patient with epithelioid GBM harboring BRAF V600E mutation, characterized by thick spinal dissemination. From relapsed tumor procured at autopsy, we established a cell line retaining the BRAF V600E mutation, TERT promoter mutation and CDKN2A/2B loss. Intracranial implantation of these cells into mice resulted in tumors closely resembling the original, characterized by epithelioid tumor cells and dissemination, and invasion into the perivascular spaces. We then confirmed the efficacy of treatment with BRAF and MEK inhibitor both in vitro and in vivo. Epithelioid GBM with BRAF V600E mutation can be considered a good treatment indication for precision medicine, and this patient-derived cell line should be useful for prediction of the tumor response and clarification of its biological characteristics.
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Affiliation(s)
- Yu Kanemaru
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan
| | - Manabu Natsumeda
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan.
| | - Masayasu Okada
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan
| | - Rie Saito
- Pathology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Daiki Kobayashi
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan
| | - Takeyoshi Eda
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan
| | - Jun Watanabe
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan
| | - Shoji Saito
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan
| | - Yoshihiro Tsukamoto
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan
| | - Makoto Oishi
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan
| | - Hirotake Saito
- Department of Radiology and Radiation Oncology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Masayuki Nagahashi
- Division of Digestive and General Surgery, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Takahiro Sasaki
- Department of Neurosurgery, Northwestern University, Chicago, IL, USA
| | - Rintaro Hashizume
- Department of Neurosurgery, Northwestern University, Chicago, IL, USA
| | - Hidefumi Aoyama
- Department of Radiology and Radiation Oncology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Toshifumi Wakai
- Division of Digestive and General Surgery, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Akiyoshi Kakita
- Pathology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Yukihiko Fujii
- From the Departments of Neurosurgery, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Japan
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18
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Oncogenic BRAF Alterations and Their Role in Brain Tumors. Cancers (Basel) 2019; 11:cancers11060794. [PMID: 31181803 PMCID: PMC6627484 DOI: 10.3390/cancers11060794] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 06/05/2019] [Accepted: 06/06/2019] [Indexed: 12/26/2022] Open
Abstract
Alterations of the v-raf murine sarcoma viral oncogene homolog B (BRAF) have been extensively studied in several tumor entities and are known to drive cell growth in several tumor entities. Effective targeted therapies with mutation-specific small molecule inhibitors have been developed and established for metastasized malignant melanoma. The BRAF V600E mutation and KIAA1549-BRAF fusion are alterations found in several brain tumors and show a distinct prognostic impact in some entities. Besides the diagnostic significance for the classification of central nervous system tumors, these alterations present possible therapy targets that may be exploitable for oncological treatments, as it has been established for malignant melanomas. In this review the different central nervous system tumors harboring BRAF alterations are presented and the diagnostic significance, prognostic role, and therapeutic potential are discussed.
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19
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Molecular genetics and therapeutic targets of pediatric low-grade gliomas. Brain Tumor Pathol 2019; 36:74-83. [PMID: 30929113 DOI: 10.1007/s10014-019-00340-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 03/19/2019] [Indexed: 12/27/2022]
Abstract
Pediatric low-grade gliomas (PLGGs) have relatively favorable prognosis and some resectable PLGGs, such as cerebellar pilocytic astrocytoma, can be cured by surgery alone. However, many PLGG cases are unresectable and some of them undergo tumor progression. Therefore, a multidisciplinary approach is necessary to treat PLGG patients. Recent genomic analysis revealed a broad genomic landscape underlying PLGG. Notably, the majority of PLGGs present MAPK pathway-associated genomic alterations and MAPK signaling-dependent tumor progression. Following preclinical evidence, many clinical trials based on molecular target therapy have been conducted on PLGG patients, some of whom exhibited durable response to target therapy. Here, we provide an overview of PLGG genetics and the evidence supporting the application of molecular target therapy in these patients.
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20
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da Nóbrega FR, Ozdemir O, Nascimento Sousa SCS, Barboza JN, Turkez H, de Sousa DP. Piplartine Analogues and Cytotoxic Evaluation against Glioblastoma. Molecules 2018; 23:E1382. [PMID: 29890617 PMCID: PMC6099735 DOI: 10.3390/molecules23061382] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 05/14/2018] [Accepted: 05/14/2018] [Indexed: 12/14/2022] Open
Abstract
Piplartine (1) is an alkamide extracted from plants of the genus Piper which shows several pharmacological properties, including antitumor activity. To improve this activity, a series of analogues based on 1 have been synthesized by esterification and amidation using the 3,4,5-trimethoxycinnamic acid-like starting material. During the study, the moieties 3-(3,4,5-trimethoxyphenyl)acrylate and 3-(3,4,5-trimethoxyphenyl)acrylamide were maintained on esters and amides respectively. Meanwhile, functional changes were exploited, and it was revealed that the presence of two aromatic rings in the side-chain was important to improve the cytotoxic activity against the U87MG cell line, such as the compound (E)-benzhydryl 3-(3,4,5-trimethoxyphenyl)acrylate (10), an ester that exhibited strong cytotoxicity and a similar level of potency to that of paclitaxel, a positive control. Compound 10 had a marked concentration-dependent inhibitory effect on the viability of the U87MG cell line with apoptotic and oxidative processes, showing good potential for altering main molecular pathways to prevent tumor development. Moreover, it has strong bioavailability with non-genotoxic and non-cytotoxic properties on human blood cells. In conclusion, the findings of the present study demonstrated that compound 10 is a promising agent that may find applications combatting diseases associated with oxidative stress and as a prototype for the development of novel drugs used in the treatment of glioblastoma.
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Affiliation(s)
- Flávio Rogério da Nóbrega
- Laboratory of Pharmaceutical Chemistry, Universidade Federal da Paraíba, João Pessoa 58051-085, Brazil.
| | - Ozlem Ozdemir
- Department of Molecular Biology and Genetics, Erzurum Technical University, Erzurum 25240, Turkey.
| | | | - Joice Nascimento Barboza
- Laboratory of Pharmaceutical Chemistry, Universidade Federal da Paraíba, João Pessoa 58051-085, Brazil.
| | - Hasan Turkez
- Department of Molecular Biology and Genetics, Erzurum Technical University, Erzurum 25240, Turkey.
- Department of Pharmacy, "G. d'Annunzio" University of Chieti-Pescara, Via dei Vestini 31, 66013 Chieti Scalo, CH, Italy.
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21
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Barthel FP, Wesseling P, Verhaak RGW. Reconstructing the molecular life history of gliomas. Acta Neuropathol 2018; 135:649-670. [PMID: 29616301 PMCID: PMC5904231 DOI: 10.1007/s00401-018-1842-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 03/16/2018] [Accepted: 03/18/2018] [Indexed: 12/20/2022]
Abstract
At the time of their clinical manifestation, the heterogeneous group of adult and pediatric gliomas carries a wide range of diverse somatic genomic alterations, ranging from somatic single-nucleotide variants to structural chromosomal rearrangements. Somatic abnormalities may have functional consequences, such as a decrease, increase or change in mRNA transcripts, and cells pay a penalty for maintaining them. These abnormalities, therefore, must provide cells with a competitive advantage to become engrained into the glioma genome. Here, we propose a model of gliomagenesis consisting of the following five consecutive phases that glioma cells have traversed prior to clinical manifestation: (I) initial growth; (II) oncogene-induced senescence; (III) stressed growth; (IV) replicative senescence/crisis; (V) immortal growth. We have integrated the findings from a large number of studies in biology and (neuro)oncology and relate somatic alterations and other results discussed in these papers to each of these five phases. Understanding the story that each glioma tells at presentation may ultimately facilitate the design of novel, more effective therapeutic approaches.
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Affiliation(s)
- Floris P Barthel
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06030, USA.
- Department of Pathology, VU University Medical Center/Brain Tumor Center Amsterdam, Amsterdam, The Netherlands.
| | - Pieter Wesseling
- Department of Pathology, VU University Medical Center/Brain Tumor Center Amsterdam, Amsterdam, The Netherlands
- Department of Pathology, Princess Máxima Center for Pediatric Oncology and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Roel G W Verhaak
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, 06030, USA
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22
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Oldrini B, Curiel-García Á, Marques C, Matia V, Uluçkan Ö, Graña-Castro O, Torres-Ruiz R, Rodriguez-Perales S, Huse JT, Squatrito M. Somatic genome editing with the RCAS-TVA-CRISPR-Cas9 system for precision tumor modeling. Nat Commun 2018; 9:1466. [PMID: 29654229 PMCID: PMC5899147 DOI: 10.1038/s41467-018-03731-w] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 03/08/2018] [Indexed: 12/21/2022] Open
Abstract
To accurately recapitulate the heterogeneity of human diseases, animal models require to recreate multiple complex genetic alterations. Here, we combine the RCAS-TVA system with the CRISPR-Cas9 genome editing tools for precise modeling of human tumors. We show that somatic deletion in neural stem cells of a variety of known tumor suppressor genes (Trp53, Cdkn2a, and Pten) leads to high-grade glioma formation. Moreover, by simultaneous delivery of pairs of guide RNAs we generate different gene fusions with oncogenic potential, either by chromosomal deletion (Bcan-Ntrk1) or by chromosomal translocation (Myb-Qk). Lastly, using homology-directed-repair, we also produce tumors carrying the homologous mutation to human BRAF V600E, frequently identified in a variety of tumors, including different types of gliomas. In summary, we have developed an extremely versatile mouse model for in vivo somatic genome editing, that will elicit the generation of more accurate cancer models particularly appropriate for pre-clinical testing.
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Affiliation(s)
- Barbara Oldrini
- Seve Ballesteros Foundation Brain Tumor Group, Cancer Cell Biology Program, Spanish National Cancer Research Center, CNIO, 28029, Madrid, Spain
| | - Álvaro Curiel-García
- Seve Ballesteros Foundation Brain Tumor Group, Cancer Cell Biology Program, Spanish National Cancer Research Center, CNIO, 28029, Madrid, Spain
| | - Carolina Marques
- Seve Ballesteros Foundation Brain Tumor Group, Cancer Cell Biology Program, Spanish National Cancer Research Center, CNIO, 28029, Madrid, Spain
| | - Veronica Matia
- Seve Ballesteros Foundation Brain Tumor Group, Cancer Cell Biology Program, Spanish National Cancer Research Center, CNIO, 28029, Madrid, Spain
| | - Özge Uluçkan
- Genes, Development, and Disease Group, Cancer Cell Biology Program, Spanish National Cancer Research Centre, CNIO, 28029, Madrid, Spain
| | - Osvaldo Graña-Castro
- Bioinformatics Unit, Structural Biology and Biocomputing Programme, CNIO, 28029, Madrid, Spain
| | - Raul Torres-Ruiz
- Molecular Cytogenetics Group, Human Cancer Genetics Program, Spanish National Cancer Research Center, CNIO, 28029, Madrid, Spain
| | - Sandra Rodriguez-Perales
- Molecular Cytogenetics Group, Human Cancer Genetics Program, Spanish National Cancer Research Center, CNIO, 28029, Madrid, Spain
| | - Jason T Huse
- Departments of Pathology and Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Massimo Squatrito
- Seve Ballesteros Foundation Brain Tumor Group, Cancer Cell Biology Program, Spanish National Cancer Research Center, CNIO, 28029, Madrid, Spain.
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23
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Tiburcio PDB, Xiao B, Berg S, Asper S, Lyne S, Zhang Y, Zhu X, Yan H, Huang LE. Functional requirement of a wild-type allele for mutant IDH1 to suppress anchorage-independent growth through redox homeostasis. Acta Neuropathol 2018; 135:285-298. [PMID: 29288440 DOI: 10.1007/s00401-017-1800-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 12/05/2017] [Accepted: 12/21/2017] [Indexed: 01/06/2023]
Abstract
Mutations of isocitrate dehydrogenase 1 (IDH1) gene are most common in glioma, arguably preceding all known genetic alterations during tumor development. IDH1 mutations nearly invariably target the enzymatic active site Arg132, giving rise to the predominant IDH1R132H. Cells harboring IDH1 R132H -heterozygous mutation produce 2-hydroxyglutarate (2-HG), which results in histone and DNA hypermethylation. Although exogenous IDH1 R132H transduction has been shown to promote anchorage-independent growth, the biological role of IDH1R132H in glioma remains debatable. In this study, we demonstrate that heterozygous IDH1 R132H suppresses but hemizygous IDH1 R132H promotes anchorage-independent growth. Whereas genetic deletion of the wild-type allele in IDH1 R132H -heterozygous cells resulted in a pronounced increase in neurosphere genesis, restoration of IDH1 expression in IDH1 R132H -hemizygous cells led to the contrary. Conversely, anchorage-independent growth was antagonistic to the mutant IDH1 function by inhibiting gene expression and 2-HG production. Furthermore, we identified that in contrast to IDH1 R132H -hemizygous neurosphere, IDH1 R132H -heterozygous cells maintained a low level of reducing power to suppress neurosphere genesis, which could be bypassed, however, by the addition of reducing agent. Taken together, these results underscore the functional importance of IDH1 mutation heterozygosity in glioma biology and indicate functional loss of mutant IDH1 as an escape mechanism underlying glioma progression and the pathway of redox homeostasis as potential therapeutic targets.
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Affiliation(s)
- Patricia D B Tiburcio
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, USA
| | - Bing Xiao
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
- Department of Neurosurgery, Nanchang University Second Affiliated Hospital, Nanchang, Jiangxi, People's Republic of China
| | - Shauna Berg
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
| | - Sydney Asper
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
| | - Sean Lyne
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
| | - Yan Zhang
- Department of Neurosurgery, Nanchang University Second Affiliated Hospital, Nanchang, Jiangxi, People's Republic of China
| | - Xingen Zhu
- Department of Neurosurgery, Nanchang University Second Affiliated Hospital, Nanchang, Jiangxi, People's Republic of China
| | - Hai Yan
- Department of Pathology, Duke University Medical Center, Durham, NC, USA
| | - L Eric Huang
- Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA.
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, USA.
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24
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Cacciatore I, Fornasari E, Marinelli L, Eusepi P, Ciulla M, Ozdemir O, Tatar A, Turkez H, Di Stefano A. Memantine-derived drugs as potential antitumor agents for the treatment of glioblastoma. Eur J Pharm Sci 2017; 109:402-411. [DOI: 10.1016/j.ejps.2017.08.030] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 08/08/2017] [Accepted: 08/26/2017] [Indexed: 10/19/2022]
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25
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Abstract
PURPOSE OF REVIEW This review will discuss the role of several key players in glioma classification and biology, namely isocitrate dehydrogenase 1 and 2 (IDH1/2), alpha thalassemia/mental retardation syndrome X-linked (ATRX), B-Raf (BRAF), telomerase reverse transcriptase (TERT), and H3K27M. RECENT FINDINGS IDH1/2 mutation delineates oligoden-droglioma, astrocytoma, and secondary glioblastoma (GBM) from primary GBM and lower-grade gliomas with biology similar to GBM. Additional mutations including TERT, 1p/19q, and ATRX further guide glioma classification and diagnosis, as well as pointing directions toward individualized treatments for these distinct molecular subtypes. ATRX and TERT mutations suggest the importance of telomere maintenance in gliomagenesis. BRAF alterations are key in certain low-grade gliomas and pediatric gliomas but rarely in high-grade gliomas in adults. Histone mutations (e.g., H3K27M) and their effect on chromatin modulation are novel mechanisms of cancer generation and uniquely seen in midline gliomas in children and young adults. Over the past decade, a remarkable accumulation of knowledge from the genomic study of gliomas has led to reclassification of tumors, new understanding of oncogenic mechanisms, and novel treatment strategies.
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26
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Shin CH, Robinson JP, Sonnen JA, Welker AE, Yu DX, VanBrocklin MW, Holmen SL. HBEGF promotes gliomagenesis in the context of Ink4a/Arf and Pten loss. Oncogene 2017; 36:4610-4618. [PMID: 28368403 PMCID: PMC5552427 DOI: 10.1038/onc.2017.83] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 02/07/2017] [Accepted: 02/26/2017] [Indexed: 12/19/2022]
Abstract
Heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF) is a ligand for the epidermal growth factor receptor (EGFR), one of the most commonly amplified receptor tyrosine kinases (RTK) in glioblastoma. While HBEGF has been found to be expressed in a subset of malignant gliomas, its sufficiency for glioma initiation has not been evaluated. In this study, we demonstrate that HBEGF can initiate glioblastoma (GBM) in mice in the context of Ink4a/Arf and Pten loss, and that these tumors are similar to the classical GBM subtype observed in patients. Isogenic astrocytes from these mice showed activation not only of Egfr but also the RTK Axl in response to HBEGF stimulation. Deletion of either Egfr or Axl decreased the tumorigenic properties of HBEGF transformed cells; however only EGFR was able to rescue the phenotype in cells lacking both RTKs indicating that Egfr is required for activation of Axl in this context. Silencing of HBEGF in vivo resulted in tumor regression and significantly increased survival suggesting that HBEGF may be a clinically relevant target.
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Affiliation(s)
- C H Shin
- Huntsman Cancer Institute, University of Utah Health Sciences Center, University of Utah, Salt Lake City, UT, USA.,Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, UT, USA
| | - J P Robinson
- Hormel Institute, University of Minnesota, Austin, MN, USA
| | - J A Sonnen
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, UT, USA.,ARUP Laboratories, Salt Lake City, UT, USA
| | - A E Welker
- Huntsman Cancer Institute, University of Utah Health Sciences Center, University of Utah, Salt Lake City, UT, USA
| | - D X Yu
- Huntsman Cancer Institute, University of Utah Health Sciences Center, University of Utah, Salt Lake City, UT, USA.,Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT, USA
| | - M W VanBrocklin
- Huntsman Cancer Institute, University of Utah Health Sciences Center, University of Utah, Salt Lake City, UT, USA.,Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, UT, USA.,Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT, USA
| | - S L Holmen
- Huntsman Cancer Institute, University of Utah Health Sciences Center, University of Utah, Salt Lake City, UT, USA.,Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, UT, USA.,Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, UT, USA
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27
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Activated MEK cooperates with Cdkn2a and Pten loss to promote the development and maintenance of melanoma. Oncogene 2017; 36:3842-3851. [PMID: 28263969 PMCID: PMC5501768 DOI: 10.1038/onc.2016.526] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 12/07/2016] [Accepted: 12/27/2016] [Indexed: 01/22/2023]
Abstract
The development of targeted inhibitors, vemurafenib and dabrafenib, has led to improved clinical outcome for melanoma patients with BRAFV600E mutations. Although the initial response to these inhibitors can be dramatic, sometimes causing complete tumor regression, the majority of melanomas eventually become resistant. Mitogen-activated protein kinase kinase (MEK) mutations are found in primary melanomas and frequently reported in BRAF melanomas that develop resistance to targeted therapy; however, melanoma is a molecularly heterogeneous cancer, and which mutations are drivers and which are passengers remains to be determined. In this study, we demonstrate that in BRAFV600E melanoma cell lines, activating MEK mutations drive resistance and contribute to suboptimal growth of melanoma cells following the withdrawal of BRAF inhibition. In this manner, the cells are drug-addicted, suggesting that melanoma cells evolve a ‘just right’ level of mitogen-activated protein kinase signaling and the additive effects of MEK and BRAF mutations are counterproductive. We also used a novel mouse model of melanoma to demonstrate that several of these MEK mutants promote the development, growth and maintenance of melanoma in vivo in the context of Cdkn2a and Pten loss. By utilizing a genetic approach to control mutant MEK expression in vivo, we were able to induce tumor regression and significantly increase survival; however, after a long latency, all tumors subsequently became resistant. These data suggest that resistance to BRAF or MEK inhibitors is probably inevitable, and novel therapeutic approaches are needed to target dormant tumors.
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28
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Brown NF, Carter T, Mulholland P. Dabrafenib in BRAFV600-mutated anaplastic pleomorphic xanthoastrocytoma. CNS Oncol 2016; 6:5-9. [PMID: 27781490 DOI: 10.2217/cns-2016-0031] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Pleomorphic xanthoastrocytoma (PXA) is a rare brain tumor. Anaplastic features are found in 20-30% of cases of PXA and are associated with poor outcomes. Typical treatment is with gross total resection, followed by radiation therapy and cytotoxic chemotherapy at relapse. BRAFV600 mutations have been identified in 38-60% of patients with PXA. Several case reports and small case series have identified clinical benefit with BRAF inhibition in patients with BRAFV600-mutated PXA. We report the second published case of successful treatment with the BRAF inhibitor dabrafenib in a female patient with relapsed anaplastic PXA with a BRAFV600 mutation, and the first published case of dabrafinib treatment following intolerance to vemurafenib.
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Affiliation(s)
- Nicholas F Brown
- Department of Oncology, University College London Hospitals, 235 Euston Road, London NW1 2BU, UK.,UCL Cancer Institute, University College London, 72 Huntley Street, London WC1E 6DD, UK
| | - Thomas Carter
- UCL Cancer Institute, University College London, 72 Huntley Street, London WC1E 6DD, UK
| | - Paul Mulholland
- Department of Oncology, University College London Hospitals, 235 Euston Road, London NW1 2BU, UK.,UCL Cancer Institute, University College London, 72 Huntley Street, London WC1E 6DD, UK
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29
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McNeill RS, Irvin DM, Miller CR. BRAF Mutations Open Doors for N-Ethyl-N-Nitrosourea-Induced Gliomagenesis. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:2551-4. [PMID: 27543966 DOI: 10.1016/j.ajpath.2016.07.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 07/17/2016] [Indexed: 12/16/2022]
Abstract
This commentary highlights the article by Wang et al that describes a preclinical model for targeting BRAF-mutant gliomas.
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Affiliation(s)
- Robert S McNeill
- Pathobiology and Translational Science Graduate Program, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - David M Irvin
- Curriculum in Genetics and Molecular Biology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - C Ryan Miller
- Pathobiology and Translational Science Graduate Program, University of North Carolina School of Medicine, Chapel Hill, North Carolina; Curriculum in Genetics and Molecular Biology, University of North Carolina School of Medicine, Chapel Hill, North Carolina; Division of Neuropathology, Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine, Chapel Hill, North Carolina; Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina; Department of Neurology and Neurosciences Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina.
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30
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Peyre M, Salaud C, Clermont-Taranchon E, Niwa-Kawakita M, Goutagny S, Mawrin C, Giovannini M, Kalamarides M. PDGF activation in PGDS-positive arachnoid cells induces meningioma formation in mice promoting tumor progression in combination with Nf2 and Cdkn2ab loss. Oncotarget 2016; 6:32713-22. [PMID: 26418719 PMCID: PMC4741724 DOI: 10.18632/oncotarget.5296] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 09/14/2015] [Indexed: 11/25/2022] Open
Abstract
The role of PDGF-B and its receptor in meningeal tumorigenesis is not clear. We investigated the role of PDGF-B in mouse meningioma development by generating autocrine stimulation of the arachnoid through the platelet-derived growth factor receptor (PDGFR) using the RCAStv-a system. To specifically target arachnoid cells, the cells of origin of meningioma, we generated the PGDStv-a mouse (Prostaglandin D synthase). Forced expression of PDGF-B in arachnoid cells in vivo induced the formation of Grade I meningiomas in 27% of mice by 8 months of age. In vitro, PDGF-B overexpression in PGDS-positive arachnoid cells lead to increased proliferation.We found a correlation of PDGFR-B expression and NF2 inactivation in a cohort of human meningiomas, and we showed that, in mice, Nf2 loss and PDGF over-expression in arachnoid cells induced meningioma malignant transformation, with 40% of Grade II meningiomas. In these mice, additional loss of Cdkn2ab resulted in a higher incidence of malignant meningiomas with 60% of Grade II and 30% of Grade III meningiomas. These data suggest that chronic autocrine PDGF signaling can promote proliferation of arachnoid cells and is potentially sufficient to induce meningiomagenesis. Loss of Nf2 and Cdkn2ab have synergistic effects with PDGF-B overexpression promoting meningioma malignant transformation.
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Affiliation(s)
- Matthieu Peyre
- Department of Neurosurgery, AP-HP, Hôpital Pitié-Salpêtrière, Paris, France.,Université Paris 6 - Pierre et Marie Curie, Paris, France.,CRICM INSERM U1127 CNRS UMR 7225, Institut du Cerveau et de la Moelle Epinière, Paris, France
| | - Céline Salaud
- Université Paris 6 - Pierre et Marie Curie, Paris, France.,CRICM INSERM U1127 CNRS UMR 7225, Institut du Cerveau et de la Moelle Epinière, Paris, France
| | - Estelle Clermont-Taranchon
- Université Paris 6 - Pierre et Marie Curie, Paris, France.,CRICM INSERM U1127 CNRS UMR 7225, Institut du Cerveau et de la Moelle Epinière, Paris, France
| | - Michiko Niwa-Kawakita
- Inserm U944, CNRS U7212, Université Paris VII, Institut Universitaire d'Hématologie, Paris, France
| | | | - Christian Mawrin
- Department of Neuropathology, Otto-von-Guericke Universität, Magdeburg, Germany
| | - Marco Giovannini
- Department of Head and Neck Surgery, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Michel Kalamarides
- Department of Neurosurgery, AP-HP, Hôpital Pitié-Salpêtrière, Paris, France.,Université Paris 6 - Pierre et Marie Curie, Paris, France.,CRICM INSERM U1127 CNRS UMR 7225, Institut du Cerveau et de la Moelle Epinière, Paris, France
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31
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Han J, Wang L, Wang X, Li K. Downregulation of Microrna-126 Contributes to Tumorigenesis of Squamous Tongue Cell Carcinoma via Targeting KRAS. Med Sci Monit 2016; 22:522-9. [PMID: 26883054 PMCID: PMC4760649 DOI: 10.12659/msm.895306] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
UNLABELLED BACKGROUND miR-126 has been reported to be differentially expressed in various malignancies, whereas its role in the pathogenesis of tongue squamous cell carcinoma (TSCC) remains largely unknown. MATERIAL AND METHODS In this study, we collected 21 pairs of TSCC cancerous and adjacent non-cancerous tissue samples, with which we performed real-time PCR to determine and compare the expression of 6 candidate miRNAs that are reportedly associated with tumorigenesis of TSCC, including miR-100, miR-451, miR-221, let-7a, miR-21, and miR-126. We further performed luciferase assay to validate KRAS as a target of miR-126, and conducted transfection to study the effect of miR-126 on proliferation and apoptosis of the cells. RESULTS We identified that miR-126 was significantly downregulated in the cancerous tissue samples compared with the non-cancerous control tissue samples. By using computational analysis, we identified that KRAS is a virtual target of miR-126, and such association was verified by using luciferase assay. In addition, we found that mRNA and protein expression level of KRAS was significantly higher in the tumor tissue than the control tissue samples. CONCLUSIONS The following in vitro experiment showed that both mRNA and protein KRAS expression were significantly decreased in SCC-15 cells in which miR-126 was overexpressed, in comparison with similar cells transfected with a negative control, while downregulation of miR-126 by transfecting the cells with miR-126 inhibitors significantly upregulated the mRNA and protein expression of KRAS. CONCLUSIONS miR-126 might be a promising diagnostic and therapeutic target in the prevention and management of TSCC patients.
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Affiliation(s)
- Jingying Han
- Department of Orthodontics, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China (mainland)
| | - Lina Wang
- Department of Orthodontics, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China (mainland)
| | - Xiaofeng Wang
- Department of Orthodontics, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China (mainland)
| | - Kun Li
- Department of Orthodontics, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China (mainland)
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32
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Pandey V, Bhaskara VK, Babu PP. Implications of mitogen-activated protein kinase signaling in glioma. J Neurosci Res 2015; 94:114-27. [PMID: 26509338 DOI: 10.1002/jnr.23687] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/22/2015] [Accepted: 10/12/2015] [Indexed: 12/22/2022]
Abstract
Gliomas are the most common primary central nervous system tumors. Gliomas originate from astrocytes, oligodendrocytes, and neural stem cells or their precursors. According to WHO classification, gliomas are classified into four different malignant grades ranging from grade I to grade IV based on histopathological features and related molecular aberrations. The induction and maintenance of these tumors can be attributed largely to aberrant signaling networks. In this regard, the mitogen-activated protein kinase (MAPK) network has been widely studied and is reported to be severely altered in glial tumors. Mutations in MAPK pathways most frequently affect RAS and B-RAF in the ERK, c-Jun N-terminal kinase (JNK), and p38 pathways leading to malignant transformation. Also, it is linked to both inherited and sequential accumulations of mutations that control receptor tyrosine kinase (RTK)-activated signal transduction pathways, cell cycle growth arrest pathways, and nonresponsive cell death pathways. Genetic alterations that modulate RTK signaling can also alter several downstream pathways, including RAS-mediated MAP kinases along with JNK pathways, which ultimately regulate cell proliferation and cell death. The present review focuses on recent literature regarding important deregulations in the RTK-activated MAPK pathway during gliomagenesis and progression.
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Affiliation(s)
- Vimal Pandey
- Laboratory of Neuroscience, Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, AP, India
| | - Vasantha Kumar Bhaskara
- Laboratory of Neuroscience, Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, AP, India
| | - Phanithi Prakash Babu
- Laboratory of Neuroscience, Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, AP, India
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33
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Weller M, Wick W, Aldape K, Brada M, Berger M, Pfister SM, Nishikawa R, Rosenthal M, Wen PY, Stupp R, Reifenberger G. Glioma. Nat Rev Dis Primers 2015; 1:15017. [PMID: 27188790 DOI: 10.1038/nrdp.2015.17] [Citation(s) in RCA: 665] [Impact Index Per Article: 73.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Gliomas are primary brain tumours that are thought to derive from neuroglial stem or progenitor cells. On the basis of their histological appearance, they have been traditionally classified as astrocytic, oligodendroglial or ependymal tumours and assigned WHO grades I-IV, which indicate different degrees of malignancy. Tremendous progress in genomic, transcriptomic and epigenetic profiling has resulted in new concepts of classifying and treating gliomas. Diffusely infiltrating gliomas in adults are now separated into three overarching tumour groups with distinct natural histories, responses to treatment and outcomes: isocitrate dehydrogenase (IDH)-mutant, 1p/19q co-deleted tumours with mostly oligodendroglial morphology that are associated with the best prognosis; IDH-mutant, 1p/19q non-co-deleted tumours with mostly astrocytic histology that are associated with intermediate outcome; and IDH wild-type, mostly higher WHO grade (III or IV) tumours that are associated with poor prognosis. Gliomas in children are molecularly distinct from those in adults, the majority being WHO grade I pilocytic astrocytomas characterized by circumscribed growth, favourable prognosis and frequent BRAF gene fusions or mutations. Ependymal tumours can be molecularly subdivided into distinct epigenetic subgroups according to location and prognosis. Although surgery, radiotherapy and alkylating agent chemotherapy are still the mainstay of treatment, individually tailored strategies based on tumour-intrinsic dominant signalling pathways and antigenic tumour profiles may ultimately improve outcome. For an illustrated summary of this Primer, visit: http://go.nature.com/TXY7Ri.
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Affiliation(s)
- Michael Weller
- Department of Neurology and Brain Tumor Center, University Hospital Zurich and University of Zurich, Frauenklinikstrasse 26, CH-8091 Zurich, Switzerland
| | - Wolfgang Wick
- Neurology Clinic, University of Heidelberg and German Cancer Research Center, Heidelberg, Germany
| | - Ken Aldape
- Department of Pathology, University Health Network, Toronto, Ontario, Canada
| | - Michael Brada
- Department of Molecular and Clinical Cancer Medicine and Department of Radiation Oncology, University of Liverpool and Clatterbridge Cancer Centre NHS Foundation Trust, Liverpool, UK
| | - Mitchell Berger
- Department of Neurological Surgery and Brain Tumor Research Center, University of California, San Francisco, California, USA
| | - Stefan M Pfister
- Division of Pediatric Neuro-Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Department of Pediatric Haematology and Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Ryo Nishikawa
- Department of Neuro-Oncology and Neurosurgery, Saitama Medical University, Saitama, Japan
| | - Mark Rosenthal
- Department of Medical Oncology, The Royal Melbourne Hospital, Victoria 3050, Australia
| | - Patrick Y Wen
- Center for Neuro-Oncology, Dana-Farber/Brigham and Women's Cancer Center, Boston, Massachusetts, USA
| | - Roger Stupp
- Department of Oncology and Brain Tumor Center, University Hospital Zurich and University of Zurich, Zurich, Switzerland
| | - Guido Reifenberger
- Department of Neuropathology, Heinrich Heine University Düsseldorf, and German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ) Heidelberg, partner site Essen/Düsseldorf, Germany
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Kegelman TP, Hu B, Emdad L, Das SK, Sarkar D, Fisher PB. In vivo modeling of malignant glioma: the road to effective therapy. Adv Cancer Res 2015; 121:261-330. [PMID: 24889534 DOI: 10.1016/b978-0-12-800249-0.00007-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Despite an increased emphasis on developing new therapies for malignant gliomas, they remain among the most intractable tumors faced today as they demonstrate a remarkable ability to evade current treatment strategies. Numerous candidate treatments fail at late stages, often after showing promising preclinical results. This disconnect highlights the continued need for improved animal models of glioma, which can be used to both screen potential targets and authentically recapitulate the human condition. This review examines recent developments in the animal modeling of glioma, from more established rat models to intriguing new systems using Drosophila and zebrafish that set the stage for higher throughput studies of potentially useful targets. It also addresses the versatility of mouse modeling using newly developed techniques recreating human protocols and sophisticated genetically engineered approaches that aim to characterize the biology of gliomagenesis. The use of these and future models will elucidate both new targets and effective combination therapies that will impact on disease management.
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Affiliation(s)
- Timothy P Kegelman
- Department of Human and Molecular Genetics, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA
| | - Bin Hu
- Department of Human and Molecular Genetics, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA
| | - Luni Emdad
- Department of Human and Molecular Genetics, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA; VCU Institute of Molecular Medicine, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA; VCU Massey Cancer Center, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA
| | - Swadesh K Das
- Department of Human and Molecular Genetics, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA; VCU Institute of Molecular Medicine, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA
| | - Devanand Sarkar
- Department of Human and Molecular Genetics, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA; VCU Institute of Molecular Medicine, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA; VCU Massey Cancer Center, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA
| | - Paul B Fisher
- Department of Human and Molecular Genetics, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA; VCU Institute of Molecular Medicine, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA; VCU Massey Cancer Center, Virginia Commonwealth University, School of Medicine, Richmond, Virginia, USA.
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Shin CH, Grossmann AH, Holmen SL, Robinson JP. The BRAF kinase domain promotes the development of gliomas in vivo. Genes Cancer 2015; 6:9-18. [PMID: 25821557 PMCID: PMC4362480 DOI: 10.18632/genesandcancer.48] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 01/23/2015] [Indexed: 12/31/2022] Open
Abstract
In-frame BRAF fusions have been observed in over 80% of sporadic pilocytic astrocytomas. In each fusion, the N-terminal autoinhibitory domain of BRAF is lost, which results in constitutive activation via the retained C-terminal kinase domain (BRAF-KD). We set out to determine if the BRAF-KD is sufficient to induce gliomas alone or in combination with Ink4a/Arf loss. Syngeneic cell lines demonstrated the transforming ability of the BRAF-KD following Ink4a/Arf loss. In vivo, somatic cell gene transfer of the BRAF-KD did not cause tumors to develop; however, gliomas were detected in 21% of the mice following Ink4a/Arf loss. Interestingly, these mice demonstrated no obvious symptoms. Histologically the tumors were highly cellular and atypical, similar to BRAFV600E tumors reported previously, but with less invasive borders. They also lacked the necrosis and vascular proliferation seen in BRAFV600E-driven tumors. The BRAF-KD-expressing astrocytes showed elevated MAPK signaling, albeit at reduced levels compared to the BRAFV600E mutant. Pharmacologic inhibition of MEK and PI3K inhibited cell growth and induced apoptosis in astrocytes expressing BRAF-KD. Our findings demonstrate that the BRAF-KD can cooperate with Ink4a/Arf loss to drive the development of gliomas and suggest that glioma development is determined by the level of MAPK signaling.
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Affiliation(s)
- Clifford H Shin
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah, USA ; Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
| | - Allie H Grossmann
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, Utah, USA ; ARUP Laboratories, Salt Lake City, Utah, USA
| | - Sheri L Holmen
- Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, Utah, USA ; Department of Oncological Sciences, University of Utah Health Sciences Center, Salt Lake City, Utah, USA ; Department of Surgery, University of Utah Health Sciences Center, Salt Lake City, Utah, USA
| | - James P Robinson
- Hormel Institute, University of Minnesota, Austin, Minnesota, USA
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Saito N, Fu J, Zheng S, Yao J, Wang S, Liu DD, Yuan Y, Sulman EP, Lang FF, Colman H, Verhaak RG, Yung WKA, Koul D. A high Notch pathway activation predicts response to γ secretase inhibitors in proneural subtype of glioma tumor-initiating cells. Stem Cells 2014; 32:301-12. [PMID: 24038660 DOI: 10.1002/stem.1528] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 07/27/2013] [Indexed: 11/07/2022]
Abstract
Genomic, transcriptional, and proteomic analyses of brain tumors reveal subtypes that differ in pathway activity, progression, and response to therapy. However, a number of small molecule inhibitors under development vary in strength of subset and pathway-specificity, with molecularly targeted experimental agents tending toward stronger specificity. The Notch signaling pathway is an evolutionarily conserved pathway that plays an important role in multiple cellular and developmental processes. We investigated the effects of Notch pathway inhibition in glioma tumor-initiating cell (GIC, hereafter GIC) populations using γ secretase inhibitors. Drug cytotoxicity testing of 16 GICs showed differential growth responses to the inhibitors, stratifying GICs into responders and nonresponders. Responder GICs had an enriched proneural gene signature in comparison to nonresponders. Also gene set enrichment analysis revealed 17 genes set representing active Notch signaling components NOTCH1, NOTCH3, HES1, MAML1, DLL-3, JAG2, and so on, enriched in responder group. Analysis of The Cancer Genome Atlas expression dataset identified a group (43.9%) of tumors with proneural signature showing high Notch pathway activation suggesting γ secretase inhibitors might be of potential value to treat that particular group of proneural glioblastoma (GBM). Inhibition of Notch pathway by γ secretase inhibitor treatment attenuated proliferation and self-renewal of responder GICs and induces both neuronal and astrocytic differentiation. In vivo evaluation demonstrated prolongation of median survival in an intracranial mouse model. Our results suggest that proneural GBM characterized by high Notch pathway activation may exhibit greater sensitivity to γ secretase inhibitor treatment, holding a promise to improve the efficiency of current glioma therapy.
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Affiliation(s)
- Norihiko Saito
- Department of Neuro-Oncology, Brain Tumor Center, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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Li H, Chen Z, Zhou S. Apoptosis in glioma-bearing rats after neural stem cell transplantation. Neural Regen Res 2014; 8:1793-802. [PMID: 25206476 PMCID: PMC4145955 DOI: 10.3969/j.issn.1673-5374.2013.19.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 06/03/2013] [Indexed: 12/22/2022] Open
Abstract
Abnormal activation of the Ras/Raf/Mek/Erk signaling cascade plays an important role in glioma. Inhibition of this aberrant activity could effectively hinder glioma cell proliferation and promote cell apoptosis. To investigate the mechanism of glioblastoma treatment by neural stem cell transplantation with respect to the Ras/Raf/Mek/Erk pathway, C6 glioma cells were prepared in suspension and then infused into the rat brain to establish a glioblastoma model. Neural stem cells isolated from fetal rats were then injected into the brain of this glioblastoma model. Results showed that Raf-1, Erk and Bcl-2 protein expression significantly increased, while Caspase-3 protein expression decreased. After transplantation of neural stem cells, Raf-1, Erk and Bcl-2 protein expression significantly decreased, while Caspase-3 protein expression significantly increased. Our findings indicate that transplantation of neural stem cells may promote apoptosis of glioma cells by inhibiting Ras/Raf/Mek/Erk signaling, and thus may represent a novel treatment approach for glioblastoma.
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Affiliation(s)
- Hua Li
- Department of Neurology, the 476 Hospital of Chinese PLA, Fuzhou 350002, Fujian Province, China
| | - Zhenjun Chen
- Department of Neurology, the 476 Hospital of Chinese PLA, Fuzhou 350002, Fujian Province, China
| | - Shaopeng Zhou
- Department of Anesthesiology, the Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai 519000, Guangdong Province, China
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Raf/MEK/ERK can regulate cellular levels of LC3B and SQSTM1/p62 at expression levels. Exp Cell Res 2014; 327:340-52. [PMID: 25128814 DOI: 10.1016/j.yexcr.2014.08.001] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 07/29/2014] [Accepted: 08/02/2014] [Indexed: 11/22/2022]
Abstract
While cellular LC3B and SQSTM1 levels serve as key autophagy markers, their regulation by different signaling pathways requires better understanding. Here, we report the mechanisms by which the Raf/MEK/ERK pathway regulates cellular LC3B and SQSTM1 levels. In different cell types, ΔRaf-1:ER- or B-Raf(V600E)-mediated MEK/ERK activation increased LC3B-I, LC3B-II, and SQSTM1/p62 levels, which was accompanied by increased BiP/GRP78 expression. Use of the autophagy inhibitors chloroquine and bafilomycin A1, or RNA interference of ATG7, suggested that these increases in LC3B and SQSTM1 levels were in part attributed to altered autophagic flux. However, intriguingly, these increases were also attributed to their increased expression. Upon Raf/MEK/ERK activation, mRNA levels of LC3B and SQSTM1 were also increased, and subsequent luciferase reporter analyses suggested that SQSTM1 upregulation was mediated at transcription level. Under this condition, transcription of BiP/GRP78 was also increased, which was necessary for Raf/MEK/ERK to regulate LC3B at the protein, but not mRNA, level. This suggests that BiP has a role in regulating autophagy machinery when Raf/MEK/ERK is activated. In conclusion, these results suggest that, under a Raf/MEK/ERK-activated condition, the steady-state cellular levels of LC3B and SQSTM1 can also be determined by their altered expression wherein BiP is utilized as an effector of the signaling.
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CAO LEI, WANG PING, LUO HUI, WANG XIRUI, WANG XIEFENG, ZHANG JUNXIA, WANG YINGYI, YAO LEI, LIU NING, YOU YONGPING. Inhibition of activated Ras suppresses multiple oncogenic Hub genes in human epithelial tumors. Int J Oncol 2014; 45:1609-17. [DOI: 10.3892/ijo.2014.2532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 06/10/2014] [Indexed: 11/06/2022] Open
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Upregulation of plasmacytoid dendritic cells in glioma. Tumour Biol 2014; 35:9661-6. [PMID: 24969556 DOI: 10.1007/s13277-014-2211-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 06/06/2014] [Indexed: 12/20/2022] Open
Abstract
The immune system fails to eradicate established tumors partly due to the induction of immune tolerance within tumor microenvironment. Plasmacytoid dendritic cells (pDCs) play critical roles in regulating immune system. In this study, we investigated pDC in the peripheral blood of glioma. CD4 + CD123 + BDCA2+ pDCs were tested from peripheral blood mononuclear cells in 40 glioma patients and 40 healthy controls by flow cytometry. The results revealed that proportion of pDCs was significantly increased in cases than in controls (0.52 ± 0.07 versus 0.21 ± 0.02 %, p < 0.001), whereas myeloid dendritic cells (mDCs) did not present any obvious difference between patients and healthy donors (0.25 ± 0.04 versus 0.18 ± 0.02 %, p = 0.217). We further studied pDCs in glioma patients with different clinical stages. Data showed that cases with smoking history had elevated level of pDCs than those non-smoker patients (0.91 ± 0.16 versus 0.48 ± 0.06 %, p = 0.004). Interestingly, we observed that patients with aphasia presented significantly elevated pDCs than those without aphasia (0.93 ± 0.12 versus 0.41 ± 0.07 %, p < 0.001). These data suggested that pDCs may be closely involved in the pathogenesis of glioma and may play roles in certain symptoms of the disease.
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Robinson GL, Robinson JP, Lastwika KJ, Holmen SL, Vanbrocklin MW. Akt signaling accelerates tumor recurrence following ras inhibition in the context of ink4a/arf loss. Genes Cancer 2014; 4:476-85. [PMID: 24386508 DOI: 10.1177/1947601913513268] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 10/27/2013] [Indexed: 12/30/2022] Open
Abstract
Aberrant activation of the RAS signaling pathway contributes to nearly all human cancers, including gliomas. To determine the dependence of high-grade gliomas on this signaling pathway, we developed a doxycycline-regulated KRas glioma mouse model. Using this model we previously demonstrated that inhibition of KRas expression in gliomas induced by activated KRas and Akt results in complete tumor regression. We have also shown that, in the context of Ink4a/Arf loss, abrogation of KRas signaling is sufficient to decrease tumor burden but resistance ensues. In this study, we sought to determine the effect of activated Akt signaling in combination with activated KRas and loss of Ink4a/Arf on the growth and recurrence of brain tumors following suppression of KRas expression. We observed significant tumor formation in Ink4a/Arf(lox/lox) mice injected with retroviruses containing tetracycline responsive element (TRE)-KRas, Tet-off, Akt, and Cre. Abrogation of KRas signaling resulted in significant tumor regression; however, resistance developed after a relatively short latency. Tumor recurrence occurred more rapidly and the tumors were more aggressive in the presence of activated Akt signaling compared with loss of Ink4a/Arf alone suggesting that this pathway contributes to tumor progression in this context.
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Affiliation(s)
- Gemma L Robinson
- Department of Surgery, University of Utah, Salt Lake City, UT, USA ; Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - James P Robinson
- Department of Surgery, University of Utah, Salt Lake City, UT, USA ; Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | | | - Sheri L Holmen
- Department of Surgery, University of Utah, Salt Lake City, UT, USA ; Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Matthew W Vanbrocklin
- Department of Surgery, University of Utah, Salt Lake City, UT, USA ; Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
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Shimamura M, Nakahara M, Orim F, Kurashige T, Mitsutake N, Nakashima M, Kondo S, Yamada M, Taguchi R, Kimura S, Nagayama Y. Postnatal expression of BRAFV600E does not induce thyroid cancer in mouse models of thyroid papillary carcinoma. Endocrinology 2013; 154:4423-30. [PMID: 23970782 DOI: 10.1210/en.2013-1174] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The mutant BRAF (BRAF(V600E)) is the most common genetic alteration in papillary thyroid carcinomas (PTCs). The oncogenicity of this mutation has been shown by some genetically engineered mouse models. However, in these mice, BRAF(V600E) is expressed in all the thyroid cells from the fetal periods, and suppresses thyroid function, thereby leading to TSH elevation, which by itself promotes thyroid tumorigenesis. To overcome these problems, we exploited 2 different approaches, both of which allowed temporally and spatially restricted expression of BRAF(V600E) in the thyroid glands. First, we generated conditional transgenic mice harboring the loxP-neo(R)-loxP-BRAF(V600E)-internal ribosome entry site-green fluorescent protein sequence [Tg(LNL-BRAF(V600E))]. The double transgenic mice (LNL-BRAF(V600E);TPO-Cre) were derived from a high expressor line of Tg(LNL-BRAF(V600E)) mice and TPO-Cre mice; the latter expresses Cre DNA recombinase under the control of thyroid-specific thyroid peroxidase (TPO) promoter and developed PTC-like lesions in early life under normal serum TSH levels due to mosaic recombination. In contrast, injection of adenovirus expressing Cre under the control of another thyroid-specific thyroglobulin (Tg) promoter (Ad-TgP-Cre) into the thyroids of LNL-BRAF(V600E) mice did not induce tumor formation despite detection of BRAF(V600E) and pERK in a small fraction of thyroid cells. Second, postnatal expression of BRAF(V600E) in a small number of thyroid cells was also achieved by injecting the lentivirus expressing loxP-green fluorescent protein-loxP-BRAF(V600E) into the thyroids of TPO-Cre mice; however, no tumor development was again observed. These results suggest that BRAF(V600E) does not appear to induce PTC-like lesions when expressed in a fraction of thyroid cells postnatally under normal TSH concentrations.
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Affiliation(s)
- Mika Shimamura
- MD, Department of Molecular Medicine, Atomic Bomb Disease Institute, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki 852-8523 Japan.
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Wang XR, Luo H, Li HL, Cao L, Wang XF, Yan W, Wang YY, Zhang JX, Jiang T, Kang CS, Liu N, You YP. Overexpressed let-7a inhibits glioma cell malignancy by directly targeting K-ras, independently of PTEN. Neuro Oncol 2013; 15:1491-501. [PMID: 24092860 DOI: 10.1093/neuonc/not107] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Altered expression of micro(mi)RNAs has been shown to be associated with tumorigenesis and tumor progression. The expression of phosphatase and tensin homolog (PTEN) plays an important role in glioma and is regarded as a prognostic marker of glioma patients. The goal of this study was to investigate the function of lethal (let)-7a miRNA in glioma cell lines with different PTEN phenotypes. METHODS One hundred ninety-eight glioma tissues were used to profile miRNA expression. RESULTS Let-7a was shown to have lower expression in high-grade glioma than in low-grade glioma. Low expression of let-7a was correlated with poor prognosis of primary glioblastoma patients. We demonstrated that K-ras was a functional target for let-7a to induce cell cycle arrest, apoptosis, and inhibition of cell migration and invasion in vitro. Our further results showed no difference in malignancy inhibition induced by let-7a in 4 glioma cells, including U87 (PTEN null), U251 (PTEN mutant), LN229 (PTEN wild type), and LN229 (PTEN small interfering RNA). The phosphatidylinositol-3 kinase/Akt and mitogen-activated protein kinase/extracellular signal-regulated kinase pathways were inhibited by let-7a, and the inhibition effects had no difference in 4 glioma cells. We demonstrated that let-7a could induce suppression of glioma in vivo by generating a glioma xenograft model. CONCLUSION Our results indicated that let-7a suppresses its target transcript K-ras and inhibits glioma malignancy independent of PTEN expression.
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Affiliation(s)
- Xi-Rui Wang
- Corresponding Authors: Yong-Ping You, PhD, Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China. ); Ning Liu, PhD, Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029 China (
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Kaul A, Chen YH, Emnett RJ, Gianino SM, Gutmann DH. Conditional KIAA1549:BRAF mice reveal brain region- and cell type-specific effects. Genesis 2013; 51:708-16. [PMID: 23893969 PMCID: PMC3808469 DOI: 10.1002/dvg.22415] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Revised: 07/10/2013] [Accepted: 07/15/2013] [Indexed: 11/06/2022]
Abstract
Low-grade brain tumors (pilocytic astrocytomas) that result from a genomic rearrangement in which the BRAF kinase domain is fused to the amino terminal of the KIAA1549 gene (KIAA1549:BRAF fusion; f-BRAF) commonly arise in the cerebellum of young children. To model this temporal and spatial specificity in mice, we generated conditional KIAA1549:BRAF strains that coexpresses green fluorescent protein (GFP). Although both primary astrocytes and neural stem cells (NSCs) from these mice express f-BRAF and GFP as well as exhibit increased MEK activity, only f-BRAF-expressing NSCs exhibit increased proliferation in vitro. Using Cre driver lines in which KIAA1549:BRAF expression was directed to NSCs (f-BRAF; BLBP-Cre mice), astrocytes (f-BRAF; GFAP-Cre mice), and NG2 progenitor cells (f-BRAF; NG2-Cre mice), increased glial cell numbers were observed only in the cerebellum of f-BRAF; BLBP-Cre mice in vivo. The availability of this unique KIAA1549:BRAF conditional transgenic mouse strain will enable future mechanistic studies aimed at defining the developmentally-regulated temporal and spatial determinants that underlie low-grade astrocytoma formation in children.
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Affiliation(s)
- Aparna Kaul
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
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Hong SK, Jeong JH, Chan AM, Park JI. AKT upregulates B-Raf Ser445 phosphorylation and ERK1/2 activation in prostate cancer cells in response to androgen depletion. Exp Cell Res 2013; 319:1732-1743. [PMID: 23701950 DOI: 10.1016/j.yexcr.2013.05.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 04/15/2013] [Accepted: 05/13/2013] [Indexed: 11/24/2022]
Abstract
Upregulated ERK1/2 activity is often correlated with AKT activation during prostate cancer (PCa) progression, yet their functional relation needs elucidation. Using androgen-deprived LNCaP cells, in which ERK1/2 activation occurs in strong correlation with AKT activation, we found that AKT-mediated B-Raf regulation is necessary for ERK1/2 activation. Specifically, in response to androgen deprivation, AKT upregulated B-Raf phosphorylation at Ser445 without affecting A-Raf or C-Raf-1. This effect of AKT was abolished by Arg25 to Ala mutation or truncating (∆4-129) the pleckstrin homology domain of AKT, indicating that the canonical AKT regulation is important for this signaling. Intriguingly, although a constitutively active AKT containing N-terminal myristoylation signal could sufficiently upregulate B-Raf phosphorylation at Ser445 in LNCaP cells, subsequent MEK/ERK activation still required hormone deprivation. In contrast, AKT activity was sufficient to induce not only B-Raf phosphorylation but also MEK/ERK activation in the hormone refractory LNCaP variant, C4-2. These data indicate that androgen depletion may induce MEK/ERK activation through a synergy between AKT-dependent and -independent mechanisms and that the latter may become deregulated in association with castration resistance. In support, consistent AKT-mediated B-Raf regulation was also detected in a panel of PCa lines derived from the cPten(-/-)L mice before and after castration. Our results also demonstrate that AKT regulates androgen receptor levels partly via the Raf/MEK/ERK pathway. This study reveals a novel crosstalk between ERK1/2 and AKT in PCa cells.
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Affiliation(s)
- Seung-Keun Hong
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Joseph H Jeong
- Department of Dermatology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Andrew M Chan
- School of Biomedical Sciences, Chinese University of Hong Kong, Hong Kong, China
| | - Jong-In Park
- Department of Biochemistry, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
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The molecular and cell biology of pediatric low-grade gliomas. Oncogene 2013; 33:2019-26. [PMID: 23624918 DOI: 10.1038/onc.2013.148] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 03/05/2013] [Accepted: 03/07/2013] [Indexed: 12/13/2022]
Abstract
Pilocytic astrocytoma (PA) is the most common glial cell tumor arising in children. Sporadic cases are associated with KIAA1549:BRAF fusion rearrangements, while 15-20% of children develop PA in the context of the neurofibromatosis 1 (NF1) inherited tumor predisposition syndrome. The unique predilection of these tumors to form within the optic pathway and brainstem (NF1-PA) and cerebellum (sporadic PA) raises the possibility that gliomagenesis requires more than biallelic inactivation of the NF1 tumor suppressor gene or expression of the KIAA1549:BRAF transcript. Several etiologic explanations include differential susceptibilities of preneoplastic neuroglial cell types in different brain regions to these glioma-causing genetic changes, contributions from non-neoplastic cells and signals in the tumor microenvironment, and genomic modifiers that confer glioma risk. As clinically-faithful rodent models of sporadic PA are currently under development, Nf1 genetically-engineered mouse (GEM) models have served as tractable systems to study the role of the cell of origin, deregulated intracellular signaling, non-neoplastic cells in the tumor microenvironment and genomic modifiers in gliomagenesis. In this report, we highlight advances in Nf1-GEM modeling and review new experimental evidence that supports the emerging concept that Nf1- and KIAA1549:BRAF-induced gliomas arise from specific cell types in particular brain locations.
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Kim JH, Huse JT, Huang Y, Lyden D, Greenfield JP. Molecular diagnostics in paediatric glial tumours. Lancet Oncol 2013; 14:e19-27. [PMID: 23276367 DOI: 10.1016/s1470-2045(12)70577-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Glial tumours in children have distinct patterns of epigenetic alteration, chromosomal structure, and gene and protein expression that differentiate them from their histological counterparts in adults. Understanding paediatric gliomas at the molecular level provides important prognostic and therapeutic insights, such as which genetic alterations confer a favourable response to adjuvant therapy, or which signalling pathways might be amenable to specific molecularly targeted agents. For clinicians, the ultimate goal is to individualise therapeutic regimens on the basis of the molecular fingerprint of a particular tumour and the prognosis conferred by this profile. In this Review, we examine a series of studies of molecular and genomic analysis of glial tumours in children, and discuss the many clinical insights that these molecular features provide.
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Affiliation(s)
- Joon-Hyung Kim
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA
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Carra E, Barbieri F, Marubbi D, Pattarozzi A, Favoni RE, Florio T, Daga A. Sorafenib selectively depletes human glioblastoma tumor-initiating cells from primary cultures. Cell Cycle 2013; 12:491-500. [PMID: 23324350 DOI: 10.4161/cc.23372] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Glioblastomas are grade IV brain tumors characterized by high aggressiveness and invasiveness, giving patients a poor prognosis. We investigated the effects of the multi-kinase inhibitor sorafenib on six cultures isolated from human glioblastomas and maintained in tumor initiating cells-enriching conditions. These cell subpopulations are thought to be responsible for tumor recurrence and radio- and chemo-resistance, representing the perfect target for glioblastoma therapy. Sorafenib reduces proliferation of glioblastoma cultures, and this effect depends, at least in part, on the inhibition of PI3K/Akt and MAPK pathways, both involved in gliomagenesis. Sorafenib significantly induces apoptosis/cell death via downregulation of the survival factor Mcl-1. We provide evidence that sorafenib has a selective action on glioblastoma stem cells, causing enrichment of cultures in differentiated cells, downregulation of the expression of stemness markers required to maintain malignancy (nestin, Olig2 and Sox2) and reducing cell clonogenic ability in vitro and tumorigenic potential in vivo. The selectivity of sorafenib effects on glioblastoma stem cells is confirmed by the lower sensitivity of glioblastoma cultures after differentiation as compared with the undifferentiated counterpart. Since current GBM therapy enriches the tumor in cancer stem cells, the evidence of a selective action of sorafenib on these cells is therapeutically relevant, even if, so far, results from first phase II clinical trials did not demonstrate its efficacy.
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Affiliation(s)
- Elisa Carra
- Department of Experimental Medicine (DIMES), University of Genova, Genova, Italy
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Kaul A, Chen YH, Emnett RJ, Dahiya S, Gutmann DH. Pediatric glioma-associated KIAA1549:BRAF expression regulates neuroglial cell growth in a cell type-specific and mTOR-dependent manner. Genes Dev 2012; 26:2561-6. [PMID: 23152448 DOI: 10.1101/gad.200907.112] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Tandem duplications involving the BRAF kinase gene have recently been identified as the most frequent genetic alteration in sporadic pediatric glioma, creating a novel fusion protein (f-BRAF) with increased BRAF activity. To define the role of f-BRAF in gliomagenesis, we demonstrate that f-BRAF regulates neural stem cell (NSC), but not astrocyte, proliferation and is sufficient to induce glioma-like lesions in mice. Moreover, f-BRAF-driven NSC proliferation results from tuberin/Rheb-mediated mammalian target of rapamycin (mTOR) hyperactivation, leading to S6-kinase-dependent degradation of p27. Collectively, these results establish mTOR pathway activation as a key growth regulatory mechanism common to both sporadic and familial low-grade gliomas in children.
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Affiliation(s)
- Aparna Kaul
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63108, USA
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Thangarajh M, Gutmann DH. Review: low-grade gliomas as neurodevelopmental disorders: insights from mouse models of neurofibromatosis-1. Neuropathol Appl Neurobiol 2012; 38:241-53. [PMID: 22035280 DOI: 10.1111/j.1365-2990.2011.01230.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Over the past few years, the traditional view of brain tumorigenesis has been revolutionized by advances in genomic medicine, molecular biology, stem cell biology and genetically engineered small-animal modelling. We now appreciate that paediatric brain tumours arise following specific genetic mutations in specialized groups of progenitor cells in concert with permissive changes in the local tumour microenvironment. This interplay between preneoplastic/neoplastic cells and non-neoplastic stromal cells is nicely illustrated by the neurofibromatosis type 1-inherited cancer syndrome, in which affected children develop low-grade astrocytic gliomas. In this review, we will use neurofibromatosis type 1 as a model system to highlight the critical role of growth control pathways, non-neoplastic cellular elements and brain region-specific properties in the development of childhood gliomas. The insights derived from examining each of these contributing factors will be instructive in the design of new therapies for gliomas in the paediatric population.
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Affiliation(s)
- M Thangarajh
- Department of Neurology, School of Medicine, Washington University, Saint Louis, MO, USA
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