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Postoperative radiotherapy timing, molecular subgroups and treatment outcomes of Thai pediatric patients with medulloblastoma. PLoS One 2023; 18:e0271778. [PMID: 36649280 PMCID: PMC9844848 DOI: 10.1371/journal.pone.0271778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 12/23/2022] [Indexed: 01/18/2023] Open
Abstract
INTRODUCTION Medulloblastoma (MB) is the most common childhood malignant brain tumor worldwide. Recently, molecular classification was established and started to play a role in the management of MB; however, studies involving molecular defined MB in Southeast Asia have been limited. We aimed to describe, and correlate clinical characteristics and molecular subgroups with therapeutic outcomes of Thai pediatric patients with MB. MATERIALS AND METHODS Pediatric MB patients treated at King Chulalongkorn Memorial Hospital in Thailand from 2006 to 2018 were recruited. Patients were classified by clinical characteristics into standard- and high-risk groups, which determined treatment regimen. Retrospectively, available tumor tissues were classified into 3 molecular subgroups using immunohistochemistry: 1) WNT, 2) SHH, and 3) non-WNT/non-SHH. The primary outcome was 5-year overall survival (OS). Risk factors associated with OS were analyzed using cox regression analysis. RESULTS Fifty-three Thai pediatric patients with MB were enrolled. The median follow-up time was 60 months. The 5-year OS for all patients, and patients with standard-risk and high-risk were 74.2%, 76.3% and 71.4%, respectively. Tumor tissues of 24 patients were available, of which 23 could be molecularly classified. Two, one and 20 were in the WNT, SHH and non-WNT/non-SHH subtypes with 5-year OS of 100%, 100% and 78.9%, respectively. Using multivariate analysis, the interval of more than 8 weeks between surgery and radiotherapy was significantly correlated with a decrease in the 5-year OS. CONCLUSION Interval between surgery and radiotherapy within 8 weeks was associated with good therapeutic outcomes among Thai pediatric patients with MB. Simplified molecular subtyping combined with clinical characteristics is practical in risk classification of patients with MB in institutes with limited resources.
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Nayak C, Singh SK. Integrated Transcriptome Profiling Identifies Prognostic Hub Genes as Therapeutic Targets of Glioblastoma: Evidenced by Bioinformatics Analysis. ACS OMEGA 2022; 7:22531-22550. [PMID: 35811900 PMCID: PMC9260928 DOI: 10.1021/acsomega.2c01820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
Glioblastoma (GBM) is the most devastating and frequent type of primary brain tumor with high morbidity and mortality. Despite the use of surgical resection followed by radio- and chemotherapy as standard therapy, the progression of GBM remains dismal with a median overall survival of <15 months. GBM embodies a populace of cancer stem cells (GSCs) that is associated with tumor initiation, invasion, therapeutic resistance, and post-treatment reoccurrence. However, understanding the potential mechanisms of stemness and their candidate biomarkers remains limited. Hence in this investigation, we aimed to illuminate potential candidate hub genes and key pathways associated with the pathogenesis of GSC in the development of GBM. The integrated analysis discovered differentially expressed genes (DEGs) between the brain cancer tissues (GBM and GSC) and normal brain tissues. Multiple approaches, including gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, were employed to functionally annotate the DEGs and visualize them through the R program. The significant hub genes were identified through the protein-protein interaction network, Venn diagram analysis, and survival analysis. We observed that the upregulated DEGs were prominently involved in the ECM-receptor interaction pathway. The downregulated genes were mainly associated with the axon guidance pathway. Five significant hub genes (CTNNB1, ITGB1, TNC, EGFR, and SHOX2) were screened out through multiple analyses. GO and KEGG analyses of hub genes uncovered that these genes were primarily enriched in disease-associated pathways such as the inhibition of apoptosis and the DNA damage repair mechanism, activation of the cell cycle, EMT (epithelial-mesenchymal transition), hormone AR (androgen receptor), hormone ER (estrogen receptor), PI3K/AKT (phosphatidylinositol 3-kinase and AKT), RTK (receptor tyrosine kinase), and TSC/mTOR (tuberous sclerosis complex and mammalian target of rapamycin). Consequently, the epigenetic regulatory network disclosed that hub genes played a vital role in the progression of GBM. Finally, candidate drugs were predicted that can be used as possible drugs to treat GBM patients. Overall, our investigation offered five hub genes (CTNNB1, ITGB1, TNC, EGFR, and SHOX2) that could be used as precise diagnostic and prognostic candidate biomarkers of GBM and might be used as personalized therapeutic targets to obstruct gliomagenesis.
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Fang FY, Rosenblum JS, Ho WS, Heiss JD. New Developments in the Pathogenesis, Therapeutic Targeting, and Treatment of Pediatric Medulloblastoma. Cancers (Basel) 2022; 14:cancers14092285. [PMID: 35565414 PMCID: PMC9100249 DOI: 10.3390/cancers14092285] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 04/26/2022] [Accepted: 05/01/2022] [Indexed: 01/25/2023] Open
Abstract
Pediatric medulloblastoma (MB) is the most common pediatric brain tumor with varying prognoses depending on the distinct molecular subtype. The four consensus subgroups are WNT, Sonic hedgehog (SHH), Group 3, and Group 4, which underpin the current 2021 WHO classification of MB. While the field of knowledge for treating this disease has significantly advanced over the past decade, a deeper understanding is still required to improve the clinical outcomes for pediatric patients, who are often vulnerable in ways that adult patients are not. Here, we discuss how recent insights into the pathogenesis of pediatric medulloblastoma have directed current and future research. This review highlights new developments in understanding the four molecular subtypes’ pathophysiology, epigenetics, and therapeutic targeting. In addition, we provide a focused discussion of recent developments in imaging, and in the surgery, chemotherapy, and radiotherapy of pediatric medulloblastoma. The article includes a brief explanation of healthcare costs associated with medulloblastoma treatment.
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Affiliation(s)
- Francia Y. Fang
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA;
| | - Jared S. Rosenblum
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA;
| | - Winson S. Ho
- Department of Neurosurgery, The University of Texas at Austin, Austin, TX 78712, USA;
| | - John D. Heiss
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
- Correspondence:
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Ray S, Chaturvedi NK, Bhakat KK, Rizzino A, Mahapatra S. Subgroup-Specific Diagnostic, Prognostic, and Predictive Markers Influencing Pediatric Medulloblastoma Treatment. Diagnostics (Basel) 2021; 12:diagnostics12010061. [PMID: 35054230 PMCID: PMC8774967 DOI: 10.3390/diagnostics12010061] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/11/2021] [Accepted: 12/18/2021] [Indexed: 12/24/2022] Open
Abstract
Medulloblastoma (MB) is the most common malignant central nervous system tumor in pediatric patients. Mainstay of therapy remains surgical resection followed by craniospinal radiation and chemotherapy, although limitations to this therapy are applied in the youngest patients. Clinically, tumors are divided into average and high-risk status on the basis of age, metastasis at diagnosis, and extent of surgical resection. However, technological advances in high-throughput screening have facilitated the analysis of large transcriptomic datasets that have been used to generate the current classification system, dividing patients into four primary subgroups, i.e., WNT (wingless), SHH (sonic hedgehog), and the non-SHH/WNT subgroups 3 and 4. Each subgroup can further be subdivided on the basis of a combination of cytogenetic and epigenetic events, some in distinct signaling pathways, that activate specific phenotypes impacting patient prognosis. Here, we delve deeper into the genetic basis for each subgroup by reviewing the extent of cytogenetic events in key genes that trigger neoplastic transformation or that exhibit oncogenic properties. Each of these discussions is further centered on how these genetic aberrations can be exploited to generate novel targeted therapeutics for each subgroup along with a discussion on challenges that are currently faced in generating said therapies. Our future hope is that through better understanding of subgroup-specific cytogenetic events, the field may improve diagnosis, prognosis, and treatment to improve overall quality of life for these patients.
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Affiliation(s)
- Sutapa Ray
- Department of Pediatrics, University of Nebraska Medical Center, 601 S Saddle Creek Road, Omaha, NE 68198, USA; (S.R.); (N.K.C.)
- Fred and Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68105, USA; (K.K.B.); (A.R.)
| | - Nagendra K. Chaturvedi
- Department of Pediatrics, University of Nebraska Medical Center, 601 S Saddle Creek Road, Omaha, NE 68198, USA; (S.R.); (N.K.C.)
- Fred and Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68105, USA; (K.K.B.); (A.R.)
| | - Kishor K. Bhakat
- Fred and Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68105, USA; (K.K.B.); (A.R.)
- Department of Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Angie Rizzino
- Fred and Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68105, USA; (K.K.B.); (A.R.)
- Eppley Institute for Research in Cancer and Allied Disease, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Sidharth Mahapatra
- Department of Pediatrics, University of Nebraska Medical Center, 601 S Saddle Creek Road, Omaha, NE 68198, USA; (S.R.); (N.K.C.)
- Fred and Pamela Buffet Cancer Center, University of Nebraska Medical Center, Omaha, NE 68105, USA; (K.K.B.); (A.R.)
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Correspondence: ; Tel.: +1-(402)-599-7754
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Trejo-Solis C, Escamilla-Ramirez A, Jimenez-Farfan D, Castillo-Rodriguez RA, Flores-Najera A, Cruz-Salgado A. Crosstalk of the Wnt/β-Catenin Signaling Pathway in the Induction of Apoptosis on Cancer Cells. Pharmaceuticals (Basel) 2021; 14:ph14090871. [PMID: 34577571 PMCID: PMC8465904 DOI: 10.3390/ph14090871] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/22/2021] [Accepted: 08/24/2021] [Indexed: 12/13/2022] Open
Abstract
The Wnt/β-catenin signaling pathway plays a major role in cell survival and proliferation, as well as in angiogenesis, migration, invasion, metastasis, and stem cell renewal in various cancer types. However, the modulation (either up- or downregulation) of this pathway can inhibit cell proliferation and apoptosis both through β-catenin-dependent and independent mechanisms, and by crosstalk with other signaling pathways in a wide range of malignant tumors. Existing studies have reported conflicting results, indicating that the Wnt signaling can have both oncogenic and tumor-suppressing roles, depending on the cellular context. This review summarizes the available information on the role of the Wnt/β-catenin pathway and its crosstalk with other signaling pathways in apoptosis induction in cancer cells and presents a modified dual-signal model for the function of β-catenin. Understanding the proapoptotic mechanisms induced by the Wnt/β-catenin pathway could open new therapeutic opportunities.
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Affiliation(s)
- Cristina Trejo-Solis
- Laboratorio Experimental de Enfermedades Neurodegenerativas, Instituto Nacional de Neurología y Neurocirugía, Ciudad de Mexico 14269, Mexico; (A.E.-R.); (A.C.-S.)
- Correspondence:
| | - Angel Escamilla-Ramirez
- Laboratorio Experimental de Enfermedades Neurodegenerativas, Instituto Nacional de Neurología y Neurocirugía, Ciudad de Mexico 14269, Mexico; (A.E.-R.); (A.C.-S.)
| | - Dolores Jimenez-Farfan
- Laboratorio de Inmunología, División de Estudios de Posgrado e Investigación, Facultad de Odontología, Universidad Nacional Autónoma de México, Ciudad de Mexico 04510, Mexico;
| | | | - Athenea Flores-Najera
- Centro Médico Nacional 20 de Noviembre, Departamento de Cirugía General, Ciudad de Mexico 03229, Mexico;
| | - Arturo Cruz-Salgado
- Laboratorio Experimental de Enfermedades Neurodegenerativas, Instituto Nacional de Neurología y Neurocirugía, Ciudad de Mexico 14269, Mexico; (A.E.-R.); (A.C.-S.)
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Nambirajan A, Gurung N, Suri V, Sarkar C, Kumar A, Singh M, Sharma MC. C19MC amplification and expression of Lin28A and Olig2 in the classification of embryonal tumors of the central nervous system: A 14-year retrospective study from a tertiary care center. Childs Nerv Syst 2021; 37:1067-1075. [PMID: 33236184 DOI: 10.1007/s00381-020-04973-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 11/12/2020] [Indexed: 10/22/2022]
Abstract
INTRODUCTION CNS embryonal tumors (CET) other than medulloblastomas (MB) and atypical teratoid/rhabdoid tumors (AT/RTs), previously designated as 'central nervous system primitive neuroectodermal tumors' ('CNS PNETs'), are a heterogenous subset of tumors with poorly defined diagnostic criteria. Other than the subset of embryonal tumor with multilayered rosettes (ETMR) defined by C19MC amplification, most CETs are diagnosed by exclusion of other molecularly defined entities and histological mimics including MB, AT/RTs, and high-grade gliomas, and termed as CET, not otherwise specified (NOS) in the 2016 WHO classification. AIM To reclassify 'CNS PNETs' as per WHO 2016, and estimate the true proportion of CET, NOS in a tertiary healthcare setting, and to evaluate the diagnostic utility of C19MC amplification, Lin28A and Olig2 expression in the subclassification of CETs. METHODS Previously diagnosed cases of 'CNS PNETs' (2002-2016) were first evaluated by immunohistochemistry (IHC) for MIC2, RelaA, L1CAM, IDH1R132H, H3K27M, H3G34R, H3G34V, INI1, and BRG1 proteins and by fluorescence in-situ hybridization (FISH) for EWSR1 translocation to exclude histological mimics. The selected CETs (case cohort) and 79 histological mimics (comparison cohort) comprising of MB, AT/RT, pineal parenchymal tumors, Ewing sarcoma, esthesioneuroblastoma, intraocular medulloepithelioma, and H3G34R mutant high-grade glioma were subject to IHC for Olig2 and Lin28A, and FISH for C19MC amplification. RESULTS Twenty-two cases of 'CNS PNETs' were retrieved, all of which were negative for the first panel of markers and showed retained INI-1/BRG1 expression. Three of them (3/22, 13.6%) showed C19MC amplification (ETMR, C19MC-altered) with ETMR histology, Lin28A positivity, and Olig2 negativity. Among the remaining 19 CETs, one showed medulloepithelioma histology (Medulloepithelioma, NOS) and remaining were non-descript small round cell tumors (CET, NOS), all negative for Lin28A. Olig2 was positive in only 3 CETs (13.6%), all being CET, NOS. All tumors in the comparison cohort were negative for C19MC amplification, Lin28A and Olig2 except for 27% of ATRTs that were Lin28A positive. CONCLUSION ETMR, C19MC-altered constitute less than 14% of CETs, with majority remaining uncharacterized as CET, NOS. Lin28A is 100% sensitive for the detection of C19MC amplification; however, its specificity is limited by its expression in ATRTs. Olig2 expression is seen only in a small subset of CET, NOS and is of limited diagnostic utility.
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Affiliation(s)
- Aruna Nambirajan
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India, 110029
| | - Niteeka Gurung
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India, 110029
| | - Vaishali Suri
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India, 110029
| | - Chitra Sarkar
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India, 110029
| | - Amandeep Kumar
- Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India, 110029
| | - Manmohan Singh
- Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India, 110029
| | - Mehar Chand Sharma
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India, 110029.
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K.M. Ip C, Yin J, K.S. Ng P, Lin SY, B. Mills G. Genomic-Glycosylation Aberrations in Tumor Initiation, Progression and Management. AIMS MEDICAL SCIENCE 2016. [DOI: 10.3934/medsci.2016.4.386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Abstract
Medulloblastoma is the most common malignant brain tumor of childhood. Although there is now long-term survival or cure for the majority of children, the survivors bear a significant burden of complications due, at least in part, to the intense therapies given to ensure eradication of the tumor. Significant efforts have been made over the years to be able to distinguish between patients who do and do not need intensive therapies. This review summarizes the history and current state of clinical risk stratification, pathologic diagnosis and genetics. Recent developments in correlation between genetics and pathology, genome-wide association studies and the biology of medulloblastoma metastasis are discussed in detail. The current state of clinical treatment trials are reviewed and placed into the perspective of potential novel therapies in the near term.
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Affiliation(s)
- Donya Aref
- University Health Network Pathology, Arthur & Sonia Labatt Brain Tumour Research Centre, Department of Laboratory Medicine & Pathobiology, Toronto, ON, Canada
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Zhukova N, Ramaswamy V, Remke M, Martin DC, Castelo-Branco P, Zhang CH, Fraser M, Tse K, Poon R, Shih DJH, Baskin B, Ray PN, Bouffet E, Dirks P, von Bueren AO, Pfaff E, Korshunov A, Jones DTW, Northcott PA, Kool M, Pugh TJ, Pomeroy SL, Cho YJ, Pietsch T, Gessi M, Rutkowski S, Bognár L, Cho BK, Eberhart CG, Conter CF, Fouladi M, French PJ, Grajkowska WA, Gupta N, Hauser P, Jabado N, Vasiljevic A, Jung S, Kim SK, Klekner A, Kumabe T, Lach B, Leonard JR, Liau LM, Massimi L, Pollack IF, Ra YS, Rubin JB, Van Meir EG, Wang KC, Weiss WA, Zitterbart K, Bristow RG, Alman B, Hawkins CE, Malkin D, Clifford SC, Pfister SM, Taylor MD, Tabori U. WNT activation by lithium abrogates TP53 mutation associated radiation resistance in medulloblastoma. Acta Neuropathol Commun 2014; 2:174. [PMID: 25539912 PMCID: PMC4297452 DOI: 10.1186/s40478-014-0174-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 12/02/2014] [Indexed: 11/25/2022] Open
Abstract
TP53 mutations confer subgroup specific poor survival for children with medulloblastoma. We hypothesized that WNT activation which is associated with improved survival for such children abrogates TP53 related radioresistance and can be used to sensitize TP53 mutant tumors for radiation. We examined the subgroup-specific role of TP53 mutations in a cohort of 314 patients treated with radiation. TP53 wild-type or mutant human medulloblastoma cell-lines and normal neural stem cells were used to test radioresistance of TP53 mutations and the radiosensitizing effect of WNT activation on tumors and the developing brain. Children with WNT/TP53 mutant medulloblastoma had higher 5-year survival than those with SHH/TP53 mutant tumours (100% and 36.6% ± 8.7%, respectively (p < 0.001)). Introduction of TP53 mutation into medulloblastoma cells induced radioresistance (survival fractions at 2Gy (SF2) of 89% ± 2% vs. 57.4% ± 1.8% (p < 0.01)). In contrast, β-catenin mutation sensitized TP53 mutant cells to radiation (p < 0.05). Lithium, an activator of the WNT pathway, sensitized TP53 mutant medulloblastoma to radiation (SF2 of 43.5% ± 1.5% in lithium treated cells vs. 56.6 ± 3% (p < 0.01)) accompanied by increased number of γH2AX foci. Normal neural stem cells were protected from lithium induced radiation damage (SF2 of 33% ± 8% for lithium treated cells vs. 27% ± 3% for untreated controls (p = 0.05). Poor survival of patients with TP53 mutant medulloblastoma may be related to radiation resistance. Since constitutive activation of the WNT pathway by lithium sensitizes TP53 mutant medulloblastoma cells and protect normal neural stem cells from radiation, this oral drug may represent an attractive novel therapy for high-risk medulloblastomas.
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Salaroli R, Ronchi A, Buttarelli FR, Cortesi F, Marchese V, Della Bella E, Renna C, Baldi C, Giangaspero F, Cenacchi G. Wnt activation affects proliferation, invasiveness and radiosensitivity in medulloblastoma. J Neurooncol 2014; 121:119-27. [PMID: 25261924 DOI: 10.1007/s11060-014-1621-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Accepted: 09/21/2014] [Indexed: 12/26/2022]
Abstract
Medulloblastomas (MBs) associated with the Wnt activation represent a subgroup with a favorable prognosis, but it remains unclear whether Wnt activation confers a less aggressive phenotype and/or enhances radiosensitivity. To investigate this issue, we evaluated the biological behavior of an MB cell line, UW228-1, stably transfected with human β-catenin cDNA encoding a nondegradable form of β-catenin (UW-B) in standard culture conditions and after radiation treatment. We evaluated the expression, transcriptional activity, and localization of β-catenin in the stably transfected cells using immunofluorescence and WB. We performed morphological analysis using light and electron microscopy. We then analyzed changes in the invasiveness, growth, and mortality in standard culture conditions and after radiation. We demonstrated that (A) Wnt activation inhibited 97 % of the invasion capability of the cells, (B) the growth of the UW-B cells was statistically significantly lower than that of all the other control cells (p < 0.01), (C) the mortality of irradiated UW-B cells was statistically significantly higher than that of the controls and their nonirradiated counterparts (p < 0.05), and (D) morphological features of neuronal differentiation were observed in the Wnt-activated cells. In tissue samples, the Ki-67 labeling index (LI) was lower in β-catenin-positive samples compared to non-β-catenin positive ones. The Ki-67 LI median (LI = 40) of the nuclear β-catenin-positive tumor samples was lower than that of non-nuclear β-catenin-positive samples (LI = 50), but the difference was not statistically significant. Overall, our data suggest that activation of the Wnt pathway reduces the proliferation and invasion of MBs and increases the tumor's radiosensitivity.
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Affiliation(s)
- Roberta Salaroli
- Department of Biomedical and Neuromotor Sciences, "Alma Mater Studiorum" University of Bologna, Via Massarenti 9, 40138, Bologna, Italy
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He M, Li Y, Zhang L, Li L, Shen Y, Lin L, Zheng W, Chen L, Bian X, Ng HK, Tang L. Curcumin suppresses cell proliferation through inhibition of the Wnt/β-catenin signaling pathway in medulloblastoma. Oncol Rep 2014; 32:173-80. [PMID: 24858998 DOI: 10.3892/or.2014.3206] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Accepted: 04/23/2014] [Indexed: 11/06/2022] Open
Abstract
Recently, the survival rate of medulloblastoma patients has greatly improved; yet, patients undergoing current treatment regimes suffer from serious therapy-related side-effects. The aim of the present study was to investigate the anticancer effects of curcumin on medulloblastoma cells by testing its capacity to suppress proliferation and regulate the Wnt/β-catenin pathway. In the present study, cell proliferation was determined by MTT assay. Cell cycle was observed by flow cytometry. The changes in the Wnt/β-catenin pathway were analyzed by immunofluorescence, western blot analysis and RT-PCR. Curcumin treatment resulted in a dose- and time-dependent inhibition of proliferation in the medulloblastoma cell line. Curcumin treatment arrested the cell-cycle at the G2/M phase. Furthermore, curcumin treatment led to activation of GSK-3β, reduced expression of β-catenin and its downstream target cyclin D1. The attenuation of the Wnt/β‑catenin pathway was due to the loss of nuclear β-catenin. In conclusion, curcumin can inhibit cell growth by suppressing the Wnt/β-catenin signaling pathway, and it has the potential to be developed as a therapeutic agent for medulloblastoma.
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Affiliation(s)
- Misi He
- Department of Pathophysiology, Chongqing Medical University, Chongqing, P.R. China
| | - Yu Li
- Department of Pathology, Insititute of Neuroscience, Chongqing Medical University, Chongqing, P.R. China
| | - Li Zhang
- Department of Pathophysiology, Chongqing Medical University, Chongqing, P.R. China
| | - Longjiang Li
- Department of Pathophysiology, Chongqing Medical University, Chongqing, P.R. China
| | - Yi Shen
- Department of Pathophysiology, Chongqing Medical University, Chongqing, P.R. China
| | - Ling Lin
- Department of Pathophysiology, Chongqing Medical University, Chongqing, P.R. China
| | - Weiping Zheng
- Experimental and Teaching Center, Chongqing Medical University, Chongqing, P.R. China
| | - Li Chen
- Experimental and Teaching Center, Chongqing Medical University, Chongqing, P.R. China
| | - Xiuwu Bian
- Institute of Pathology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing, P.R. China
| | - Ho-Keung Ng
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, SAR, P.R. China
| | - Li Tang
- Department of Pathophysiology, Chongqing Medical University, Chongqing, P.R. China
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Rogers HA, Mayne C, Chapman RJ, Kilday JP, Coyle B, Grundy RG. PI3K pathway activation provides a novel therapeutic target for pediatric ependymoma and is an independent marker of progression-free survival. Clin Cancer Res 2013; 19:6450-60. [PMID: 24077346 DOI: 10.1158/1078-0432.ccr-13-0222] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Currently, there are few effective adjuvant therapies for pediatric ependymoma outside confocal radiation, and prognosis remains poor. The phosphoinositide 3-kinase (PI3K) pathway is one of the most commonly activated pathways in cancer. PI3Ks transduce signals from growth factors and cytokines, resulting in the phosphorylation and activation of AKT, which in turn induces changes in cell growth, proliferation, and apoptosis. EXPERIMENTAL DESIGN PI3K pathway status was analyzed in ependymoma using gene expression data and immunohistochemical analysis of phosphorylated AKT (P-AKT). The effect of the PI3K pathway on cell proliferation was investigated by immunohistochemical analysis of cyclin D1 and Ki67, plus in vitro functional analysis. To identify a potential mechanism of PI3K pathway activation, PTEN protein expression and the mutation status of PI3K catalytic subunit α-isoform gene (PIK3CA) was investigated. RESULTS Genes in the pathway displayed significantly higher expression in supratentorial than in posterior fossa and spinal ependymomas. P-AKT protein expression, indicating pathway activation, was seen in 72% of tumors (n = 169) and P-AKT expression was found to be an independent marker of a poorer progression-free survival. A significant association between PI3K pathway activation and cell proliferation was identified, suggesting that pathway activation was influencing this process. PTEN protein loss was not associated with P-AKT staining and no mutations were identified in PIK3CA. CONCLUSIONS Our results suggest that the PI3K pathway could act as a biomarker, not only identifying patients with a worse prognosis but also those that could be treated with therapies targeted against the pathway, a strategy potentially effective in a high percentage of ependymoma patients.
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Affiliation(s)
- Hazel A Rogers
- Authors' Affiliation: Children's Brain Tumour Research Centre, D Floor Medical School, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
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13
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Ranjan A, Kaur N, Tiwari V, Singh Y, Chaturvedi MM, Tandon V. 3,4-Dimethoxyphenyl Bis-benzimidazole Derivative, Mitigates Radiation-Induced DNA Damage. Radiat Res 2013; 179:647-62. [DOI: 10.1667/rr3246.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Atul Ranjan
- Department of Chemistry, University of Delhi, Delhi, India
| | - Navrinder Kaur
- Department of Chemistry, University of Delhi, Delhi, India
| | - Vinod Tiwari
- Department of Chemistry, University of Delhi, Delhi, India
| | - Yogendra Singh
- Institute of Genomics and Integrative Biology, Delhi, India
| | | | - Vibha Tandon
- Department of Chemistry, University of Delhi, Delhi, India
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The role of the WNT/β-catenin pathway in central nervous system primitive neuroectodermal tumours (CNS PNETs). Br J Cancer 2013; 108:2130-41. [PMID: 23591193 PMCID: PMC3670474 DOI: 10.1038/bjc.2013.170] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Background: Central nervous system primitive neuroectodermal tumours (CNS PNETs) are embryonal tumours occurring predominantly in children. Current lack of knowledge regarding their underlying biology hinders development of more effective treatments. We previously identified WNT/β-catenin pathway activation in one-third of CNS PNETs, which was potentially linked to a better prognosis. In this study, we have extended our cohort, achieving a statistically significant correlation with prognosis. We additionally investigated the biological effects of WNT/β-catenin pathway activation in tumour pathogenesis. Methods: A total of 42 primary and 8 recurrent CNS PNETs were analysed for WNT/β-catenin pathway status using β-catenin immunohistochemistry. Genomic copy number and mRNA expression data were analysed to identify a molecular profile linked to WNT/β-catenin pathway activation. Results: Pathway activation was seen in 26% of CNS PNETs and was significantly associated with longer overall survival. Genes displaying a significant difference in expression levels, between tumours with and without WNT/β-catenin pathway activation, included several involved in normal CNS development suggesting aberrant pathway activation may be disrupting this process. Conclusion: We have identified WNT/β-catenin pathway status as a marker, which could potentially be used to stratify disease risk for patients with CNS PNET. Gene expression data suggest pathway activation is disrupting normal differentiation in the CNS.
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15
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Silva RD, Marie SKN, Uno M, Matushita H, Wakamatsu A, Rosemberg S, Oba-Shinjo SM. CTNNB1, AXIN1 and APC expression analysis of different medulloblastoma variants. Clinics (Sao Paulo) 2013; 68:167-72. [PMID: 23525311 PMCID: PMC3584274 DOI: 10.6061/clinics/2013(02)oa08] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Accepted: 10/15/2012] [Indexed: 01/07/2023] Open
Abstract
OBJECTIVES We investigated four components of the Wnt signaling pathway in medulloblastomas. Medulloblastoma is the most common type of malignant pediatric brain tumor, and the Wnt signaling pathway has been shown to be activated in this type of tumor. METHODS Sixty-one medulloblastoma cases were analyzed for β-catenin gene (CTNNB1) mutations, β-catenin protein expression via immunostaining and Wnt signaling pathway-related gene expression. All data were correlated with histological subtypes and patient clinical information. RESULTS CTNNB1 sequencing analysis revealed that 11 out of 61 medulloblastomas harbored missense mutations in residues 32, 33, 34 and 37, which are located in exon 3. These mutations alter the glycogen synthase kinase-3β phosphorylation sites, which participate in β-catenin degradation. No significant differences were observed between mutation status and histological medulloblastoma type, patient age and overall or progression-free survival times. Nuclear β-catenin accumulation, which was observed in 27.9% of the cases, was not associated with the histological type, CTNNB1 mutation status or tumor cell dissemination. The relative expression levels of genes that code for proteins involved in the Wnt signaling pathway (CTNNB1, APC, AXIN1 and WNT1) were also analyzed, but no significant correlations were found. In addition, large-cell variant medulloblastomas presented lower relative CTNNB1 expression as compared to the other tumor variants. CONCLUSIONS A small subset of medulloblastomas carry CTNNB1 mutations with consequent nuclear accumulation of β-catenin. The Wnt signaling pathway plays a role in classic, desmoplastic and extensive nodularity medulloblastoma variants but not in large-cell medulloblastomas.
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Affiliation(s)
- Roseli da Silva
- Laboratory of Molecular and Cellular Biology, Department of Neurology, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
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16
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Bartlett F, Kortmann R, Saran F. Medulloblastoma. Clin Oncol (R Coll Radiol) 2013; 25:36-45. [DOI: 10.1016/j.clon.2012.09.008] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/04/2012] [Accepted: 08/13/2012] [Indexed: 12/18/2022]
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17
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Northcott PA, Dubuc AM, Pfister S, Taylor MD. Molecular subgroups of medulloblastoma. Expert Rev Neurother 2012; 12:871-84. [PMID: 22853794 DOI: 10.1586/ern.12.66] [Citation(s) in RCA: 121] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Recent efforts at stratifying medulloblastomas based on their molecular features have revolutionized our understanding of this morbidity. Collective efforts by multiple independent groups have subdivided medulloblastoma from a single disease into four distinct molecular subgroups characterized by disparate transcriptional signatures, mutational spectra, copy number profiles and, most importantly, clinical features. We present a summary of recent studies that have contributed to our understanding of the core medulloblastoma subgroups, focusing largely on clinically relevant discoveries that have already, and will continue to, shape research.
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Affiliation(s)
- Paul A Northcott
- The Arthur & Sonia Labatt Brain Tumour Research Center, Hospital for Sick Children, Toronto, ON, Canada
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18
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WNT/β-catenin pathway activation in Myc immortalised cerebellar progenitor cells inhibits neuronal differentiation and generates tumours resembling medulloblastoma. Br J Cancer 2012; 107:1144-52. [PMID: 22929883 PMCID: PMC3461168 DOI: 10.1038/bjc.2012.377] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background: Medulloblastoma is the most common malignant childhood brain tumour. Aberrant activation of the WNT/β-catenin pathway occurs in approximately 25% of medulloblastomas. However, its role in medulloblastoma pathogenesis is not understood. Methods: We have developed a model of WNT/β-catenin pathway-activated medulloblastoma. Pathway activation was induced in a Myc immortalised cerebellar progenitor cell line through stable expression of Wnt1. In vitro and in vivo analysis was undertaken to understand the effect of pathway activation and identify the potential cell of origin. Results: Tumours that histologically resembled classical medulloblastoma formed in vivo using cells overexpressing Wnt1, but not with the control cell line. Wnt1 overexpression inhibited neuronal differentiation in vitro, suggesting WNT/β-catenin pathway activation prevents cells terminally differentiating, maintaining them in a more ‘stem-like’ state. Analysis of cerebellar progenitor cell markers demonstrated the cell line resembled cells from the cerebellar ventricular zone. Conclusion: We have developed a cell line with the means of orthotopically modelling WNT/β-catenin pathway-activated medulloblastoma. We provide evidence of the role pathway activation is playing in tumour pathogenesis and suggest medulloblastomas can arise from cells other than granule cell progenitors. This cell line is a valuable resource to further understand the role of pathway activation in tumorigenesis and for investigation of targeted therapies.
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Picard D, Miller S, Hawkins CE, Bouffet E, Rogers HA, Chan TSY, Kim SK, Ra YS, Fangusaro J, Korshunov A, Toledano H, Nakamura H, Hayden JT, Chan J, Lafay-Cousin L, Hu PX, Fan X, Muraszko KM, Pomeroy SL, Lau CC, Ng HK, Jones C, Meter TV, Clifford SC, Eberhart C, Gajjar A, Pfister SM, Grundy RG, Huang A. Markers of survival and metastatic potential in childhood CNS primitive neuro-ectodermal brain tumours: an integrative genomic analysis. Lancet Oncol 2012; 13:838-48. [PMID: 22691720 PMCID: PMC3615440 DOI: 10.1016/s1470-2045(12)70257-7] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Childhood CNS primitive neuro-ectodermal brain tumours (PNETs) are very aggressive brain tumours for which the molecular features and best treatment approaches are unknown. We assessed a large cohort of these rare tumours to identify molecular markers to enhance clinical management of this disease. METHODS We obtained 142 primary hemispheric CNS PNET samples from 20 institutions in nine countries and examined transcriptional profiles for a subset of 51 samples and copy number profiles for a subset of 77 samples. We used clustering, gene, and pathway enrichment analyses to identify tumour subgroups and group-specific molecular markers, and applied immunohistochemical and gene-expression analyses to validate and assess the clinical significance of the subgroup markers. FINDINGS We identified three molecular subgroups of CNS PNETs that were distinguished by primitive neural (group 1), oligoneural (group 2), and mesenchymal lineage (group 3) gene-expression signatures with differential expression of cell-lineage markers LIN28 and OLIG2. Patients with group 1 tumours were most often female (male:female ratio 0·61 for group 1 vs 1·25 for group 2 and 1·63 for group 3; p=0·043 [group 1 vs groups 2 and 3]), youngest (median age at diagnosis 2·9 years [95% CI 2·4-5·2] for group 1 vs 7·9 years [6·0-9·7] for group 2 and 5·9 years [4·9-7·8] for group 3; p=0·005), and had poorest survival (median survival 0·8 years [95% CI 0·5-1·2] in group 1, 1·8 years [1·4-2·3] in group 2 and 4·3 years [0·8-7·8] in group 3; p=0·019). Patients with group 3 tumours had the highest incidence of metastases at diagnosis (no distant metastasis:metastasis ratio 0·90 for group 3 vs 2·80 for group 1 and 5·67 for group 2; p=0·037). INTERPRETATION LIN28 and OLIG2 are promising diagnostic and prognostic molecular markers for CNS PNET that warrant further assessment in prospective clinical trials. FUNDING Canadian Institute of Health Research, Brainchild/SickKids Foundation, and the Samantha Dickson Brain Tumour Trust.
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Affiliation(s)
- Daniel Picard
- Division of Hematology-Oncology, Arthur and Sonia Labatt Brain Tumour Research Centre, Dept of Pediatrics, Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Suzanne Miller
- Children's Brain Tumour Research Centre, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | | | - Eric Bouffet
- Division of Hematology-Oncology, Arthur and Sonia Labatt Brain Tumour Research Centre, Dept of Pediatrics, Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Hazel A Rogers
- Children's Brain Tumour Research Centre, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Tiffany SY Chan
- Division of Hematology-Oncology, Arthur and Sonia Labatt Brain Tumour Research Centre, Dept of Pediatrics, Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Seung-Ki Kim
- Dept of Neurosurgery, Seoul National University Children's Hospital, Seoul, South Korea
| | - Young-Shin Ra
- Dept of Neurosurgery, Asan Medical Center, Seoul, Korea
| | - Jason Fangusaro
- Division of Pediatric Hematology/Oncology and Stem Cell Transplantation, Children's Memorial Hospital, Chicago, USA
| | - Andrey Korshunov
- Clinical Cooperation Unit Neuropathology, German Cancer Research Center, Heidelberg, Germany
| | | | | | - James T Hayden
- Northern Institute for Cancer Research, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Jennifer Chan
- Dept of Pathology & Laboratory Medicine, University of Calgary, Calgary, Canada
| | - Lucie Lafay-Cousin
- Dept of Pediatric Oncology, Alberta Children's Hospital, Calgary, Canada
| | - Ping X Hu
- The Centre for Applied Genomics, Hospital for Sick Children, Toronto, Canada
| | - Xing Fan
- Dept of Neurosurgery, University of Michigan Medical School, Ann Arbor, USA
| | - Karin M Muraszko
- Dept of Neurosurgery, University of Michigan Medical School, Ann Arbor, USA
| | | | - Ching C Lau
- Texas Children's Cancer Center, Baylor College of Medicine, Houston, USA
| | - Ho-Keung Ng
- Dept of Anatomical and Cellular Pathology, Chinese University of Hong Kong, Hong Kong, China
| | - Chris Jones
- Dept of Paediatric Molecular Pathology, Institute of Cancer Research, Sutton, United Kingdom
| | | | - Steven C Clifford
- Northern Institute for Cancer Research, Newcastle University, Newcastle Upon Tyne, United Kingdom
| | - Charles Eberhart
- Division of Pathology, John Hopkins University School of Medicine, Baltimore, USA
| | - Amar Gajjar
- Neuro-oncology Division, St. Jude Children's Research Hospital, Memphis, USA
| | - Stefan M Pfister
- German Cancer Research Centre, and Paediatric, Haematology and Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Richard G Grundy
- Children's Brain Tumour Research Centre, Queen's Medical Centre, University of Nottingham, Nottingham, United Kingdom
| | - Annie Huang
- Division of Hematology-Oncology, Arthur and Sonia Labatt Brain Tumour Research Centre, Dept of Pediatrics, Hospital for Sick Children, University of Toronto, Toronto, Canada
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20
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Abstract
Primary brain tumours are difficult to manage clinically due to their abilities to invade adjacent tissue and infiltrate distant neuropil. These contribute to challenges in surgical management and also limit the effectiveness of radiotherapy. Despite initial responses to chemotherapy, most tumours become chemo-resistant, leading to relapse. Recent identification and isolation of brain cancer stem cells (BCSCs) have broadened our understanding of the molecular pathogenesis and potential Achilles' heel of brain tumours. BCSCs are thought to drive and propagate the tumour and therefore present an important target for further investigations. This review explores the history of the discovery of BCSCs and the evolving concept of "cancer stem cells" in neuro-oncology. We attempt to present a balanced view on the subject and also to update the readers on the molecular biology of BCSCs. Lastly, we outline the potential strategies to target BCSCs which will translate into specific and effective therapies for brain tumours.
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Larson JD, Largaespada DA. Review: In vivo models for defining molecular subtypes of the primitive neuroectodermal tumor genome: current challenges and solutions. In Vivo 2012; 26:487-500. [PMID: 22773561 PMCID: PMC3516387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Primitive neuroectodermal tumors (PNET) of the brain include medulloblastoma (MB) and central nervous system primitive neuroectodermal tumor (CNS PNET) subtypes, which share histological features yet differ at the genomic level and in clinical outcome. Delineation of the genetic anomalies between PNET subtypes is a current challenge for establishing effective targeted therapeutic strategies against these aggressive tumors. Current efforts have demonstrated that specific molecular pathways drive a subset of MB and CNS PNET, but the genetic basis for the deadliest forms of these tumors remains poorly understood and anecdotal. This is in part due to an overall lack of biologically relevant in vivo and in vitro model systems capable of direct comparison and identification of the genetic origins among PNET subtypes. Forward genetic, random mutagenesis in mice is an effective phenotype-driven method to model the genetic origins of human disease including cancer. We have applied this method to PNET by developing a single Sleeping Beauty transposon insertional mutagenesis mouse model that recapitulates the morphological similarities and genetic heterogeneity of MB and CNS PNET capable of identifying genetic drivers important for genesis of PNET. Importantly, this model has allowed new PNET phenotypes to be observed and is designed to reveal biologically relevant candidate oncogenes and tumor suppressor genes for MB and CNS PNET molecular subgroups in mice and humans. The ultimate goal of the approach we have taken is to uncover new understanding of the genetic basis for MB and CNS PNET development, how they are distinguished from each other, and offer potential targets for therapeutic testing to improve patient clinical outcome.
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Affiliation(s)
- Jon D Larson
- The Center For Genome Engineering and Masonic Cancer Center, University of Minnesota, 6-160 Jackson Hall, 321 Church Street South East, Minneapolis, MN 55455, USA
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22
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Miller S, Ward JH, Rogers HA, Lowe J, Grundy RG. Loss of INI1 protein expression defines a subgroup of aggressive central nervous system primitive neuroectodermal tumors. Brain Pathol 2012; 23:19-27. [PMID: 22672440 DOI: 10.1111/j.1750-3639.2012.00610.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 05/21/2012] [Indexed: 01/29/2023] Open
Abstract
Pediatric embryonal brain tumors can be difficult to classify. Atypical teratoid rhabdoid tumors (ATRT) contain rhabdoid cells, while primitive neuroectodermal tumors (PNETs) are composed of "small round blue cells." Loss of INI1 is a common event in ATRT; therefore, we investigated if the loss of INI1 protein expression was also observed in central nervous system (CNS) PNET and pineoblastoma. A histological review of 42 CNS PNETs and six pineoblastomas was performed. INI1 expression was assessed by immunohistochemistry. Sequencing was performed on the mutational hotspots of INI1. INI1-immunonegative tumors were further investigated using fluorescence in situ hybridization. Epithelial membrane antigen (EMA) protein expression was assessed in six CNS PNETs to further define the phenotype. Five CNS PNETs without rhabdoid cell morphology were immuno-negative for both INI1 and EMA. Of these primary CNS PNET patients, three died <11 months postdiagnosis, which was dissimilar to the INI1-immunopositive primary CNS PNETs where 18/24 (75%) patients were alive 1 year postdiagnosis. We have identified a small subgroup of CNS PNETs which lack INI1 protein expression, but have no evidence of rhabdoid cell morphology. INI1 protein loss may occur through mechanisms other than gene deletion. INI1 immunohistochemistry should be performed for all CNS PNET cases.
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Affiliation(s)
- Suzanne Miller
- Children's Brain Tumour Research Centre, School of Clinical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham, UK
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23
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Taylor MD, Northcott PA, Korshunov A, Remke M, Cho YJ, Clifford SC, Eberhart CG, Parsons DW, Rutkowski S, Gajjar A, Ellison DW, Lichter P, Gilbertson RJ, Pomeroy SL, Kool M, Pfister SM. Molecular subgroups of medulloblastoma: the current consensus. Acta Neuropathol 2012; 123:465-72. [PMID: 22134537 PMCID: PMC3306779 DOI: 10.1007/s00401-011-0922-z] [Citation(s) in RCA: 1307] [Impact Index Per Article: 108.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 11/19/2011] [Accepted: 11/22/2011] [Indexed: 12/14/2022]
Abstract
Medulloblastoma, a small blue cell malignancy of the cerebellum, is a major cause of morbidity and mortality in pediatric oncology. Current mechanisms for clinical prognostication and stratification include clinical factors (age, presence of metastases, and extent of resection) as well as histological subgrouping (classic, desmoplastic, and large cell/anaplastic histology). Transcriptional profiling studies of medulloblastoma cohorts from several research groups around the globe have suggested the existence of multiple distinct molecular subgroups that differ in their demographics, transcriptomes, somatic genetic events, and clinical outcomes. Variations in the number, composition, and nature of the subgroups between studies brought about a consensus conference in Boston in the fall of 2010. Discussants at the conference came to a consensus that the evidence supported the existence of four main subgroups of medulloblastoma (Wnt, Shh, Group 3, and Group 4). Participants outlined the demographic, transcriptional, genetic, and clinical differences between the four subgroups. While it is anticipated that the molecular classification of medulloblastoma will continue to evolve and diversify in the future as larger cohorts are studied at greater depth, herein we outline the current consensus nomenclature, and the differences between the medulloblastoma subgroups.
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Affiliation(s)
- Michael D. Taylor
- Division of Neurosurgery, Hospital for Sick Children, University of Toronto, Toronto, Canada
- Program in Developmental and Stem Cell Biology, Arthur and Sonia Labatt Brain Tumour Research Centre, Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Paul A. Northcott
- Program in Developmental and Stem Cell Biology, Arthur and Sonia Labatt Brain Tumour Research Centre, Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Andrey Korshunov
- Clinical Cooperation Unit Neuropathology, German Cancer Research Center, Heidelberg, Germany
| | - Marc Remke
- Division of Molecular Genetics, German Cancer Research Center, Heidelberg, Germany
- Department of Pediatric Hematology and Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Yoon-Jae Cho
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, USA
| | - Steven C. Clifford
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne, UK
| | - Charles G. Eberhart
- Departments of Pathology, Ophthalmology and Oncology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - D. Williams Parsons
- Department of Pediatrics, Texas Children’s Cancer Center, Baylor College of Medicine, Houston, USA
| | - Stefan Rutkowski
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Amar Gajjar
- Department of Oncology, St. Jude Children’s Research Hospital, Memphis, USA
| | - David W. Ellison
- Department of Pathology, St. Jude Children’s Research Hospital, Memphis, USA
| | - Peter Lichter
- Division of Molecular Genetics, German Cancer Research Center, Heidelberg, Germany
| | - Richard J. Gilbertson
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, USA
| | - Scott L. Pomeroy
- Department of Neurology, Children’s Hospital Boston, Harvard Medical School, Boston, USA
| | - Marcel Kool
- Division of Molecular Genetics, German Cancer Research Center, Heidelberg, Germany
| | - Stefan M. Pfister
- Division of Molecular Genetics, German Cancer Research Center, Heidelberg, Germany
- Department of Pediatric Hematology and Oncology, Heidelberg University Hospital, Heidelberg, Germany
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24
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Miller S, Rogers HA, Lyon P, Rand V, Adamowicz-Brice M, Clifford SC, Hayden JT, Dyer S, Pfister S, Korshunov A, Brundler MA, Lowe J, Coyle B, Grundy RG. Genome-wide molecular characterization of central nervous system primitive neuroectodermal tumor and pineoblastoma. Neuro Oncol 2011; 13:866-79. [PMID: 21798848 DOI: 10.1093/neuonc/nor070] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Central nervous system primitive neuroectodermal tumor (CNS PNET) and pineoblastoma are highly malignant embryonal brain tumors with poor prognoses. Current therapies are based on the treatment of pediatric medulloblastoma, even though these tumors are distinct at both the anatomical and molecular level. CNS PNET and pineoblastoma have a worse clinical outcome than medulloblastoma; thus, improved therapies based on an understanding of the underlying biology of CNS PNET and pineoblastoma are needed. To this end, we characterized the genomic alterations of 36 pediatric CNS PNETs and 8 pineoblastomas using Affymetrix single nucleotide polymorphism arrays. Overall, the majority of CNS PNETs contained a greater degree of genomic imbalance than pineoblastomas, with gain of 19p (8 [27.6%] of 29), 2p (7 [24.1%] of 29), and 1q (6 [20.7%] of 29) common events in primary CNS PNETs. Novel gene copy number alterations were identified and corroborated by Genomic Identification of Significant Targets In Cancer (GISTIC) analysis: gain of PCDHGA3, 5q31.3 in 62.1% of primary CNS PNETs and all primary pineoblastomas and FAM129A, 1q25 in 55.2% of primary CNS PNETs and 50% of primary pineoblastomas. Comparison of our GISTIC data with publically available data for medulloblastoma confirmed these CNS PNET-specific copy number alterations. With use of the collection of 5 primary and recurrent CNS PNET pairs, we found that gain of 2p21 was maintained at relapse in 80% of cases. Novel gene copy number losses included OR4C12, 11p11.12 in 48.2% of primary CNS PNETs and 50% of primary pineoblastomas. Loss of CDKN2A/B (9p21.3) was identified in 14% of primary CNS PNETs and was significantly associated with older age among children (P = .05). CADPS, 3p14.2 was lost in 27.6% of primary CNS PNETs and was associated with poor prognosis (P = .043). This genome-wide analysis revealed the marked molecular heterogeneity of CNS PNETs and enabled the identification of novel genes and clinical associations potentially involved in the pathogenesis of these tumors.
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Affiliation(s)
- Suzanne Miller
- Children’s Brain Tumour Research Centre, School of Clinical Sciences, Queen’s Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
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25
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Cimmino F, Scoppettuolo MN, Carotenuto M, De Antonellis P, Dato VD, De Vita G, Zollo M. Norcantharidin impairs medulloblastoma growth by inhibition of Wnt/β-catenin signaling. J Neurooncol 2011; 106:59-70. [PMID: 21735115 DOI: 10.1007/s11060-011-0645-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 06/18/2011] [Indexed: 01/12/2023]
Abstract
Medulloblastoma is one of the leading causes of morbidity and mortality in pediatric cancer. Wnt-active tumors, an independent molecular subgroup in medulloblastoma, are characterized by a distinct pattern of genomic aberrations. We assessed the anticancer activity of cantharidin and norcantharidin against medulloblastoma, as cell lines in vitro and in athymic nude mice in vivo. Cantharidin and norcantharidin treatment impaired the growth of DAOY and UW228 medulloblastoma cells and promoted the loss of β-catenin activation and the β-catenin nuclearization linked to N-cadherin impairment in vitro. Intra-peritoneal administration of norcantharidin inhibited the growth of intra-cerebellum tumors in orthotopic xenograft nude mice. Analysis of the xenograft tissues revealed enhanced neuronal differentiation and reduced β-catenin expression. Our findings suggest that norcantharidin has potential therapeutic applications in the treatment of medulloblastoma as a result of its ability to cross the blood-brain barrier and its impairment of Wnt-β-catenin signaling.
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Affiliation(s)
- Flora Cimmino
- CEINGE, Centro di Ingegneria Genetica, Biotecnologie Avanzate, Via Gaetano Salvatore 486, 80145 Naples, Italy
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26
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Azizi AA, Li L, Ströbel T, Chen WQ, Slavc I, Lubec G. Identification of c-myc-dependent proteins in the medulloblastoma cell line D425Med. Amino Acids 2011; 42:2149-63. [DOI: 10.1007/s00726-011-0953-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Accepted: 05/26/2011] [Indexed: 12/27/2022]
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Abstract
INTRODUCTION The term of "medulloblastoma" refers to cerebellar tumors belonging to the family of primitive neuro-ectodermic tumors (PNET). Medulloblastomas represent 40% of cerebellar tumors, 15 to 20% of brain tumors and the first cause of malignant brain tumors in childhood. Seventy to 80% of cases are diagnosed in children versus 20 to 30% in adults. UPDATED KNOWLEDGE Diagnosis is based on clinical and radiological exams, and proved on pathological analysis in association with molecular biology. Treatment comprises surgery, craniospinal radiotherapy except for children under five years of age and chemotherapy according to age and high-risk criteria. Medulloblastoma is a rare case of a central nervous system tumor which is radio- and chemo-sensitive. Treatment goals are, on one hand, to improve the survival rates and, on the other hand, to avoid late neurocognitive, neuroendocrine and orthopedic side effects related to radiation therapy, notably in children. The prognosis is relatively good, with a five year survival rate over 75% after complete resection of a localized tumor although sequelae may still compromise outcome. PERSPECTIVES AND CONCLUSION Management of patients with medulloblastoma implies a multidisciplinary approach combining the contributions of neurosurgery, neuroradiology, pediatric oncology, neuro-oncology and radiotherapy teams.
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28
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Abstract
Embryonal brain tumors are a heterogeneous group of neoplasms united by the presence of poorly differentiated stem-like cells. Molecular details are increasingly being used to separate them into biologically and clinically meaningful groups. For medulloblastoma, integrated mRNA expression profiling and DNA analysis by a number of research groups defines 4-6 distinctive molecular variants. A subset with prominent Wnt activity is associated with good clinical outcomes and classic histology. Medulloblastomas showing a Hedgehog gene expression signature are frequently of the desmoplastic/nodular subtype. Interestingly, Hedgehog activity is found in tumors arising either in infants or older teenagers and adults. The association of clinically aggressive medulloblastoma with MYC expression, large cell/anaplastic change and high levels of photoreceptor differentiation transcripts has also been noted in several studies. Immunohistochemical analysis of just one or two genes per molecular medulloblastoma variant may be sufficient for accurate classification, and this would be of great practical utility if validated. Advances have also been made in the classification of central nervous system (CNS) Primitive Neuroectodermal Tumors (PNET), as several groups have identified an amplicon at chromosome 19q13.41-42, which appears to define a unique PNET subtype associated with prominent true rosettes, young age and very poor outcomes.
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Affiliation(s)
- Charles G Eberhart
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Md 21205, USA.
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29
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Molecular diagnostics of CNS embryonal tumors. Acta Neuropathol 2010; 120:553-66. [PMID: 20882288 DOI: 10.1007/s00401-010-0751-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Revised: 09/20/2010] [Accepted: 09/22/2010] [Indexed: 12/18/2022]
Abstract
Tremendous progress has recently been made in both molecular subgrouping, and the establishment of prognostic biomarkers for embryonal brain tumors, particularly medulloblastoma. Several prognostic biomarkers that were initially identified in retrospective cohorts of medulloblastoma, including MYC and MYCN amplification, nuclear β-catenin accumulation, and chromosome 17 aberrations have now been validated in clinical trials. Moreover, molecular subgroups based on distinct transcriptome profiles have been consistently reported from various groups on different platforms demonstrating that the concept of distinct medulloblastoma subgroups is very robust. Well-described subgroups of medulloblastomas include tumors showing wingless signaling pathway (Wnt) activation, and another characterized by sonic hedgehog pathway activity. Two or more additional subgroups were consistently reported to contain the vast majority of high-risk tumors, including most tumors with metastatic disease at diagnosis and/or large cell/anaplastic histology. Several years ago, atypical teratoid rhabdoid tumor (AT/RT) was recognized as a separate entity based on its distinct biology and particularly aggressive clinical behavior. These tumors may occur supra or infratentorially and are usually found to have genetic alterations of SMARCB1 (INI1/hSNF5), a tumor suppressor gene located on chromosome 22q. Subsequent loss of SMARCB1 protein expression comprises a relatively specific and sensitive diagnostic marker for AT/RT. For CNS primitive neuroectodermal tumors (CNS PNETs), a consistent finding has been that they are molecularly distinct from medulloblastoma. Furthermore, a distinct fraction of CNS PNETs with particularly poor prognosis only occurring in young children was delineated, which was previously labeled ependymoblastoma or embryonal tumor with abundant neuropil and true rosettes (ETANTR) and which is morphologically characterized by the presence of multilayered "ependymoblastic" rosettes. This group of tumors shows a unique cytogenetic abnormality not seen in other brain tumors: focal amplification of a micro-RNA cluster at chromosome 19q13.42, which has never been found to be amplified in other CNS PNETs, medulloblastoma or AT/RT. In summary, these consistent findings have significantly contributed to our ability to sub-classify embryonal brain tumors into clinically and biologically meaningful strata and, for some of the subgroups, have led to the identification of specific targets for future development of molecularly targeted therapies.
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Primitive neuroectodermal tumors in patients with testicular germ cell tumors usually resemble pediatric-type central nervous system embryonal neoplasms and lack chromosome 22 rearrangements. Mod Pathol 2010; 23:972-80. [PMID: 20348883 DOI: 10.1038/modpathol.2010.70] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Primitive neuroectodermal tumors (PNETs) are one of the most frequent types of 'non-germ cell' tumor in patients with testicular germ cell tumors and have a guarded prognosis when present in metastatic sites after cisplatin-based chemotherapy. Improved treatments, including targeted therapy, require understanding the biology of these neoplasms. We therefore analyzed the morphologic, immunohistochemical and molecular biologic features of 14 PNETs from 14 patients with concurrent or previous testicular germ cell tumors; 12 tumors were from metastatic sites and 2 were primary in the testis. Using standard light microscopic criteria for central nervous system and peripheral PNETs, we classified nine tumors as medulloepithelioma, three as medulloblastoma/supratentorial PNET, one as neuroblastic tumor with abundant neuropil and true rosettes and one as small cell embryonal tumor/PNET (Ewing sarcoma-like). Immunostains directed against INI1, CD57, S-100 protein, NeuN, WT1, neurofilament, CD99, GFAP, synaptophysin, chromogranin, AE1/AE3 cytokeratin, Fli-1 and collagen IV were performed for each case. INI1 was diffusely and strongly positive in all tumors whereas the other stains, except for cytoplasmic WT1 (which showed substantial reactivity in most tumors), were mostly focal to negative, including CD99 (eight negative, six focal) and Fli-1 (all negative). The most consistently reactive 'neuroendocrine' marker was CD57. Each case was also analyzed for chromosome 22 rearrangements using a FISH-based break-apart probe method. Only 1 tumor, classified as medulloepithelioma, was scored positive for chromosome 22 translocation (22% rearranged cells) and the remaining 13 were negative, including the one case that resembled peripheral PNET. We conclude that PNETs derived from testicular germ cell tumors mostly resemble central nervous system PNETs and generally lack the chromosome 22 translocation of peripheral PNETs. Future treatment strategies should take these findings into account.
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Swartling FJ, Grimmer MR, Hackett CS, Northcott PA, Fan QW, Goldenberg DD, Lau J, Masic S, Nguyen K, Yakovenko S, Zhe XN, Gilmer HCF, Collins R, Nagaoka M, Phillips JJ, Jenkins RB, Tihan T, Vandenberg SR, James CD, Tanaka K, Taylor MD, Weiss WA, Chesler L. Pleiotropic role for MYCN in medulloblastoma. Genes Dev 2010; 24:1059-72. [PMID: 20478998 DOI: 10.1101/gad.1907510] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Medulloblastoma (MB) is the most common malignant brain tumor of childhood. Sonic Hedgehog (SHH) signaling drives a minority of MB, correlating with desmoplastic pathology and favorable outcome. The majority, however, arises independently of SHH and displays classic or large cell anaplastic (LCA) pathology and poor prognosis. To identify common signaling abnormalities, we profiled mRNA, demonstrating misexpression of MYCN in the majority of human MB and negligible expression in normal cerebella. We clarified a role in pathogenesis by targeting MYCN (and luciferase) to cerebella of transgenic mice. MYCN-driven MB showed either classic or LCA pathologies, with Shh signaling activated in approximately 5% of tumors, demonstrating that MYCN can drive MB independently of Shh. MB arose at high penetrance, consistent with a role for MYCN in initiation. Tumor burden correlated with bioluminescence, with rare metastatic spread to the leptomeninges, suggesting roles for MYCN in both progression and metastasis. Transient pharmacological down-regulation of MYCN led to both clearance and senescence of tumor cells, and improved survival. Targeted expression of MYCN thus contributes to initiation, progression, and maintenance of MB, suggesting a central role for MYCN in pathogenesis.
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Affiliation(s)
- Fredrik J Swartling
- University of California at San Francisco, San Francisco, California 94158, USA
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Chronic viral infection and primary central nervous system malignancy. J Neuroimmune Pharmacol 2010; 5:387-403. [PMID: 20387126 PMCID: PMC2914282 DOI: 10.1007/s11481-010-9204-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Accepted: 03/05/2010] [Indexed: 01/08/2023]
Abstract
Primary central nervous system (CNS) tumors cause significant morbidity and mortality in both adults and children. While some of the genetic and molecular mechanisms of neuro-oncogenesis are known, much less is known about possible epigenetic contributions to disease pathophysiology. Over the last several decades, chronic viral infections have been associated with a number of human malignancies. In primary CNS malignancies, two families of viruses, namely polyomavirus and herpesvirus, have been detected with varied frequencies in a number of pediatric and adult histological tumor subtypes. However, establishing a link between chronic viral infection and primary CNS malignancy has been an area of considerable controversy, due in part to variations in detection frequencies and methodologies used among researchers. Since a latent viral neurotropism can be seen with a variety of viruses and a widespread seropositivity exists among the population, it has been difficult to establish an association between viral infection and CNS malignancy based on epidemiology alone. While direct evidence of a role of viruses in neuro-oncogenesis in humans is lacking, a more plausible hypothesis of neuro-oncomodulation has been proposed. The overall goals of this review are to summarize the many human investigations that have studied viral infection in primary CNS tumors, discuss potential neuro-oncomodulatory mechanisms of viral-associated CNS disease and propose future research directions to establish a more firm association between chronic viral infections and primary CNS malignancies.
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Li M, Lee KF, Lu Y, Clarke I, Shih D, Eberhart C, Collins VP, Van Meter T, Picard D, Zhou L, Boutros PC, Modena P, Liang ML, Scherer SW, Bouffet E, Rutka JT, Pomeroy SL, Lau CC, Taylor MD, Gajjar A, Dirks PB, Hawkins CE, Huang A. Frequent amplification of a chr19q13.41 microRNA polycistron in aggressive primitive neuroectodermal brain tumors. Cancer Cell 2009; 16:533-46. [PMID: 19962671 PMCID: PMC3431561 DOI: 10.1016/j.ccr.2009.10.025] [Citation(s) in RCA: 187] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Revised: 08/03/2009] [Accepted: 10/23/2009] [Indexed: 12/19/2022]
Abstract
We discovered a high-level amplicon involving the chr19q13.41 microRNA (miRNA) cluster (C19MC) in 11/45 ( approximately 25%) primary CNS-PNET, which results in striking overexpression of miR-517c and 520g. Constitutive expression of miR-517c or 520g promotes in vitro and in vivo oncogenicity, modulates cell survival, and robustly enhances growth of untransformed human neural stem cells (hNSCs) in part by upregulating WNT pathway signaling and restricting differentiation of hNSCs. Remarkably, the C19MC amplicon, which is very rare in other brain tumors (1/263), identifies an aggressive subgroup of CNS-PNET with distinct gene-expression profiles, characteristic histology, and dismal survival. Our data implicate miR-517c and 520g as oncogenes and promising biological markers for CNS-PNET and provide important insights into oncogenic properties of the C19MC locus.
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Affiliation(s)
- Meihua Li
- Division of Hematology-Oncology, Hospital for Sick Children, Toronto, ON M5G 0A3, Canada
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