35 research outputs found

    Clonal mutations in primary human glial tumors: evidence in support of the mutator hypothesis

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    <p>Abstract</p> <p>Background</p> <p>A verifiable consequence of the mutator hypothesis is that even low grade neoplasms would accumulate a large number of mutations that do not influence the tumor phenotype (clonal mutations). In this study, we have attempted to quantify the number of clonal mutations in primary human gliomas of astrocytic cell origin. These alterations were identified in tumor tissue, microscopically confirmed to have over 70% neoplastic cells.</p> <p>Methods</p> <p>Random Amplified Polymorphic DNA (RAPD) analysis was performed using a set of fifteen 10-mer primers of arbitrary but definite sequences in 17 WHO grade II astrocytomas (low grade diffuse astrocytoma or DA) and 16 WHO grade IV astrocytomas (Glioblastoma Multiforme or GBM). The RAPD profile of the tumor tissue was compared with that of the leucocyte DNA of the same patient and alteration(s) scored. A quantitative estimate of the overall genomic changes in these tumors was obtained by 2 different modes of calculation.</p> <p>Results</p> <p>The overall change in the tumors was estimated to be 4.24% in DA and 2.29% in GBM by one method and 11.96% and 6.03% in DA and GBM respectively by the other. The difference between high and lower grade tumors was statistically significant by both methods.</p> <p>Conclusion</p> <p>This study demonstrates the presence of extensive clonal mutations in gliomas, more in lower grade. This is consistent with our earlier work demonstrating that technique like RAPD analysis, unbiased for locus, is able to demonstrate more intra-tumor genetic heterogeneity in lower grade gliomas compared to higher grade. The results support the mutator hypothesis proposed by Loeb.</p

    Medulloblastoma outcome is adversely associated with overexpression of EEF1D, RPL30, and RPS20 on the long arm of chromosome 8

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    BACKGROUND: Medulloblastoma is the most common malignant brain tumor of childhood. Improvements in clinical outcome require a better understanding of the genetic alterations to identify clinically significant biological factors and to stratify patients accordingly. In the present study, we applied cytogenetic characterization to guide the identification of biologically significant genes from gene expression microarray profiles of medulloblastoma. METHODS: We analyzed 71 primary medulloblastomas for chromosomal copy number aberrations (CNAs) using comparative genomic hybridization (CGH). Among 64 tumors that we previously analyzed by gene expression microarrays, 27 were included in our CGH series. We analyzed clinical outcome with respect to CNAs and microarray results. We filtered microarray data using specific CNAs to detect differentially expressed candidate genes associated with survival. RESULTS: The most frequent lesions detected in our series involved chromosome 17; loss of 16q, 10q, or 8p; and gain of 7q or 2p. Recurrent amplifications at 2p23-p24, 2q14, 7q34, and 12p13 were also observed. Gain of 8q is associated with worse overall survival (p = 0.0141), which is not entirely attributable to MYC amplification or overexpression. By applying CGH results to gene expression analysis of medulloblastoma, we identified three 8q-mapped genes that are associated with overall survival in the larger group of 64 patients (p < 0.05): eukaryotic translation elongation factor 1D (EEF1D), ribosomal protein L30 (RPL30), and ribosomal protein S20 (RPS20). CONCLUSION: The complementary use of CGH and expression profiles can facilitate the identification of clinically significant candidate genes involved in medulloblastoma growth. We demonstrate that gain of 8q and expression levels of three 8q-mapped candidate genes (EEF1D, RPL30, RPS20) are associated with adverse outcome in medulloblastoma

    OLIG2 is differentially expressed in pediatric astrocytic and in ependymal neoplasms.

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    The bHLH transcription factor, OLIG2, is universally expressed in adult human gliomas and, as a major factor in the development of oligodendrocytes, is expressed at the highest levels in low-grade oligodendroglial tumors. In addition, it is functionally required for the formation of high-grade astrocytomas in a genetically relevant murine model. The pediatric gliomas have genomic profiles that are different from the corresponding adult tumors and accordingly, the expression of OLIG2 in non-oligodendroglial pediatric gliomas is not well documented within specific tumor types. In the current study, the pattern of OLIG2 expression in a spectrum of 90 non-oligodendroglial pediatric gliomas varied from very low levels in the ependymomas (cellular and tanycytic) to high levels in pilocytic astrocytoma, and in the diffuse-type astrocytic tumors (WHO grades II-IV). With dual-labeling, glioblastoma had the highest percentage of OLIG2 expressing cells that were also Ki-67 positive (mean = 16.3%) whereas pilocytic astrocytoma WHO grade I and astrocytoma WHO grade II had the lowest (0.9 and 1%, respectively); most of the Ki-67 positive cells in the diffuse-type astrocytomas (WHO grade II-III) were also OLIG2 positive (92-94%). In contrast to the various types of pediatric astrocytic tumors, all ependymomas WHO grade II, regardless of site of origin, showed at most minimal OLIG2 expression, suggesting that OLIG2 function in pediatric gliomas is cell lineage dependent

    Spinal ependymomas. Part 2: Ependymomas of the filum terminale

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    The interactive web-based program MSmonitor for self-management and multidisciplinary care in multiple sclerosis: utilization and valuation by&nbsp;patients

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    Peter Joseph Jongen,1,2 Ludovicus G Sinnige,3 Bj&ouml;rn M van Geel,4 Freek Verheul,5 Wim I Verhagen,6 Ruud A van der Kruijk,7 Reinoud Haverkamp,8 Hans M Schrijver,9 Jacoba C Baart,10 Leo H Visser,11 Edo P Arnoldus,12 Herman Jacobus Gilhuis,13 Paul Pop,14 Monique Booy,15 Marco Heerings,16 Anton&nbsp;Kool,17 Esther van Noort17 1Department of Community and Occupational Medicine, University Medical Center Groningen, University of Groningen, Groningen, 2MS4 Research Institute, Nijmegen, 3Multiple Sclerosis Centre Leeuwarden, Medical Centre Leeuwarden, Leeuwarden, 4Department of Neurology, Medical Centre Alkmaar, Alkmaar, 5Department of Neurology, Groene Hart Hospital, Gouda, 6Department of Neurology, Canisius Wilhelmina Hospital, Nijmegen, 7Department of Neurology, Slingeland Hospital, Doetinchem, 8Department of Neurology, Zuwe Hofpoort Hospital, Woerden, 9Multiple Sclerosis Centre, Westfries Gasthuis, Hoorn, 10Department of Neurology, Ziekenhuisgroep Twente, Almelo-Hengelo, 11Multiple Sclerosis Centre Midden Brabant, St Elisabeth Hospital, Tilburg, 12Multiple Sclerosis Centre Midden Brabant, Tweesteden Hospital, 13Department of Neurology, Reinier de Graaf Gasthuis, Delft, 14Department of Neurology, Viecuri Medical Centre, Venlo-Venray, 15Multiple Sclerosis Centre, Amphia Hospital, Breda, 16MH Advies en organisatiebureau, Assen, 17Curavista bv, Geertruidenberg, the Netherlands Background: MSmonitor is an interactive web-based program for self-management and integrated, multidisciplinary care in multiple sclerosis.Methods: To assess the utilization and valuation by persons with multiple sclerosis, we held an online survey among those who had used the program for at least 1 year. We evaluated the utilization and meaningfulness of the program&rsquo;s elements, perceived use of data by neurologists and nurses, and appreciation of care, self-management, and satisfaction.Results: Fifty-five persons completed the questionnaire (estimated response rate 40%). The Multiple Sclerosis Impact Profile (MSIP), Medication and Adherence Inventory, Activities Diary, and electronic consultation (e-consult) were used by 40%, 55%, 47%, and 44% of respondents and were considered meaningful by 83%, 81%, 54%, and 88%, respectively. During out-patient consultations, nurses reportedly used the MSmonitor data three to six times more frequently than neurologists. As to nursing care, more symptoms were dealt with (according to 54% of respondents), symptoms were better discussed (69%), and the overall quality of care had improved (60%) since the use of the program. As to neurological care, these figures were 24%, 31%, and 27%, respectively. In 46% of the respondents, the insight into their symptoms and disabilities had increased since the use of the program; the MSIP, Activities Diary, and e-consult had contributed most to this improvement. The overall satisfaction with the program was 3.5 out of 5, and 73% of the respondents would recommend the program to other persons with multiple sclerosis.Conclusion: A survey among persons with multiple sclerosis using the MSmonitor program showed that the MSIP, Medication and Adherence Inventory, Activities Diary, and e-consult were frequently used and that the MSIP, Medication and Adherence Inventory, and e-consult were appreciated the most. Moreover, the quality of nursing care, but not so neurological care, had improved, which may relate to nurses making more frequent use of the MSmonitor data than neurologists. Keywords: patient-reported outcome, impact, adherence, diary, inventory, e-consul
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