WOS

Permanent URI for this collectionhttps://hdl.handle.net/11443/932

Browse

Search Results

Now showing 1 - 6 of 6
  • Item
    Clinical Proton MR Spectroscopy in Central Nervous System Disorders
    (RADIOLOGICAL SOC NORTH AMERICA, 2014-01-01) Gulin, O. Z.; Alger, Jeffry R.; Barker, Peter B.; Bartha, Robert; Bizzi, Alberto; Boesch, Chris; Bolan, Patrick J.; Brindle, Kevin M.; Cudalbu, Cristina; Dincer, Alp; Dydak, Ulrike; Emir, Uzay E.; Frahm, Jens; Gonzalez, Ramon Gilberto; Gruber, Stephan; Gruetter, Rolf; Gupta, Rakesh K.; Heerschap, Arend; Henning, Anke; Hetherington, Hoby P.; Howe, Franklyn A.; Hueppi, Petra S.; Hurd, Ralph E.; Kantarci, Kejal; Klomp, Dennis W. J.; Kreis, Roland; Kruiskamp, Marijn J.; Leach, Martin O.; Lin, Alexander P.; Luijten, Peter R.; Marjanska, Malgorzata; Maudsley, Andrew A.; Meyerhoff, Dieter J.; Mountford, Carolyn E.; Nelson, Sarah J.; Pamir, M. Necmettin; Pan, Jullie W.; Peet, Andrew C.; Poptani, Harish; Posse, Stefan; Pouwels, Petra J. W.; Ratai, Eva-Maria; Ross, Brian D.; Scheenen, Tom W. J.; Schuster, Christian; Smith, Ian C. P.; Soher, Brian J.; Tkac, Ivan; Vigneron, Daniel B.; Kauppinen, Risto A.; Grp, M.R.S. Consensus
    A large body of published work shows that proton (hydrogen 1 {[}H-1]) magnetic resonance (MR) spectroscopy has evolved from a research tool into a clinical neuroimaging modality. Herein, the authors present a summary of brain disorders in which MR spectroscopy has an impact on patient management, together with a critical consideration of common data acquisition and processing procedures. The article documents the impact of 1H MR spectroscopy in the clinical evaluation of disorders of the central nervous system. The clinical usefulness of 1H MR spectroscopy has been established for brain neoplasms, neonatal and pediatric disorders (hypoxia-ischemia, inherited metabolic diseases, and traumatic brain injury), demyelinating disorders, and infectious brain lesions. The growing list of disorders for which 1H MR spectroscopy may contribute to patient management extends to neurodegenerative diseases, epilepsy, and stroke. To facilitate expanded clinical acceptance and standardization of MR spectroscopy methodology, guidelines are provided for data acquisition and analysis, quality assessment, and interpretation. Finally, the authors offer recommendations to expedite the use of robust MR spectroscopy methodology in the clinical setting, including incorporation of technical advances on clinical units. (c) RSNA, 2014
  • Item
    High-resolution Whole-Genome Analysis of Skull Base Chordomas Implicates FHIT Loss in Chordoma Pathogenesis
    (NEOPLASIA PRESS, 2012-01-01) Diaz, Roberto Jose; Guduk, Mustafa; Romagnuolo, Rocco; Smith, Christian A.; Northcott, Paul; Shih, David; Berisha, Fitim; Flanagan, Adrienne; Munoz, David G.; Cusimano, Michael D.; Pamir, M. Necmettin; Rutka, James T.
    Chordoma is a rare tumor arising in the sacrum, clivus, or vertebrae. It is often not completely resectable and shows a high incidence of recurrence and progression with shortened patient survival and impaired quality of life. Chemo-therapeutic options are limited to investigational therapies at present. Therefore, adjuvant therapy for control of tumor recurrence and progression is of great interest, especially in skull base lesions where complete tumor resection is often not possible because of the proximity of cranial nerves. To understand the extent of genetic instability and associated chromosomal and gene losses or gains in skull base chordoma, we undertook whole-genome single-nucleotide polymorphism microarray analysis of flash frozen surgical chordoma specimens, 21 from the clivus and 1 from C1 to C2 vertebrae. We confirm the presence of a deletion at 9p involving CDKN2A, CDKN2B, and MTAP but at a much lower rate (22\%) than previously reported for sacral chordoma. At a similar frequency (21\%), we found aneuploidy of chromosome 3. Tissue microarray immunohistochemistry demonstrated absent or reduced fragile histidine triad (FHIT) protein expression in 98\% of sacral chordomas and 67\% of skull base chordomas. Our data suggest that chromosome 3 aneuploidy and epigenetic regulation of FHIT contribute to loss of the FHIT tumor suppressor in chordoma. The finding that FHIT is lost in a majority of chordomas provides new insight into chordoma pathogenesis and points to a potential new therapeutic target for this challenging neoplasm. Neoplasia (2012) 14, 788-798
  • Item
    MEOX2 homeobox gene promotes growth of malignant gliomas
    (OXFORD UNIV PRESS INC, 2022-01-01) Schoenrock, Anna; Heinzelmann, Elisa; Steffl, Bianca; Demirdizen, Engin; Narayanan, Ashwin; Krunic, Damir; Baehr, Marion; Park, Jong-Whi; Schmidt, Claudia; Oezduman, Koray; Pamir, M. Necmettin; Wick, Wolfgang; Bestvater, Felix; Weichenhan, Dieter; Plass, Christoph; Taranda, Julian; Mall, Moritz; Turcan, Sevin
    Background Glioblastoma (GBM) is an aggressive tumor that frequently exhibits gain of chromosome 7, loss of chromosome 10, and aberrantly activated receptor tyrosine kinase signaling pathways. Previously, we identified Mesenchyme Homeobox 2 (MEOX2), a gene located on chromosome 7, as an upregulated transcription factor in GBM. Overexpressed transcription factors can be involved in driving GBM. Here, we aimed to address the role of MEOX2 in GBM. Methods Patient-derived GBM tumorspheres were used to constitutively knockdown or overexpress MEOX2 and subjected to in vitro assays including western blot to assess ERK phosphorylation. Cerebral organoid models were used to investigate the role of MEOX2 in growth initiation. Intracranial mouse implantation models were used to assess the tumorigenic potential of MEOX2. RNA-sequencing, ACT-seq, and CUT\&Tag were used to identify MEOX2 target genes. Results MEOX2 enhanced ERK signaling through a feed-forward mechanism. We identified Ser(155) as a putative ERK-dependent phosphorylation site upstream of the homeobox-domain of MEOX2. S155A substitution had a major effect on MEOX2 protein levels and altered its subnuclear localization. MEOX2 overexpression cooperated with p53 and PTEN loss in cerebral organoid models of human malignant gliomas to induce cell proliferation. Using high-throughput genomics, we identified putative transcriptional target genes of MEOX2 in patient-derived GBM tumorsphere models and a fresh frozen GBM tumor. Conclusions We identified MEOX2 as an oncogenic transcription regulator in GBM. MEOX2 increases proliferation in cerebral organoid models of GBM and feeds into ERK signaling that represents a core signaling pathway in GBM.
  • Item
    Genomic Analysis of Non-NF2 Meningiomas Reveals Mutations in TRAF7, KLF4, AKT1, and SMO
    (AMER ASSOC ADVANCEMENT SCIENCE, 2013-01-01) Clark, Victoria E.; Erson-Omay, E. Zeynep; Serin, Akdes; Yin, Jun; Cotney, Justin; Oezduman, Koray; Avsar, Timuin; Li, Jie; Murray, Phillip B.; Henegariu, Octavian; Yilmaz, Saliha; Guenel, Jennifer Moliterno; Carrion-Grant, Geneive; Yilmaz, Baran; Grady, Conor; Tanrikulu, Bahattin; Bakircioglu, Mehmet; Kaymakcalan, Hande; Caglayan, Ahmet Okay; Sencar, Leman; Ceyhun, Emre; Atik, A. Fatih; Bayri, Yasar; Bai, Hanwen; Kolb, Luis E.; Hebert, Ryan M.; Omay, S. Bulent; Mishra-Gorur, Ketu; Choi, Murim; Overton, John D.; Holland, Eric C.; Mane, Shrikant; State, Matthew W.; Bilguevar, Kaya; Baehring, Joachim M.; Gutin, Philip H.; Piepmeier, Joseph M.; Vortmeyer, Alexander; Brennan, Cameron W.; Pamir, M. Necmettin; Kilic, Tuerker; Lifton, Richard P.; Noonan, James P.; Yasuno, Katsuhito; Guenel, Murat
    We report genomic analysis of 300 meningiomas, the most common primary brain tumors, leading to the discovery of mutations in TRAF7, a proapoptotic E3 ubiquitin ligase, in nearly one-fourth of all meningiomas. Mutations in TRAF7 commonly occurred with a recurrent mutation ( K409Q) in KLF4, a transcription factor known for its role in inducing pluripotency, or with AKT1(E17K), a mutation known to activate the PI3K pathway. SMO mutations, which activate Hedgehog signaling, were identified in similar to 5\% of non-NF2 mutant meningiomas. These non-NF2 meningiomas were clinically distinctive-nearly always benign, with chromosomal stability, and originating from the medial skull base. In contrast, meningiomas with mutant NF2 and/or chromosome 22 loss were more likely to be atypical, showing genomic instability, and localizing to the cerebral and cerebellar hemispheres. Collectively, these findings identify distinct meningioma subtypes, suggesting avenues for targeted therapeutics.
  • Item
    Longitudinal analysis of treatment-induced genomic alterations in gliomas
    (BIOMED CENTRAL LTD, 2017-01-01) Erson-Omay, E. Zeynep; Henegariu, Octavian; Omay, S. Bulent; Harmanci, Akdes Serin; Youngblood, Mark W.; Mishra-Gorur, Ketu; Li, Jie; Ozduman, Koray; Carrion-Grant, Geneive; Clark, Victoria E.; Caglar, Caner; Bakircioglu, Mehmet; Pamir, M. Necmettin; Tabar, Viviane; Vortmeyer, Alexander O.; Bilguvar, Kaya; Yasuno, Katsuhito; DeAngelis, Lisa M.; Baehring, Joachim M.; Moliterno, Jennifer; Gunel, Murat
    Background: Glioblastoma multiforme (GBM) constitutes nearly half of all malignant brain tumors and has a median survival of 15 months. The standard treatment for these lesions includes maximal resection, radiotherapy, and chemotherapy
  • Item
    Correlation of anatomical involvement patterns of insular gliomas with subnetworks of the limbic system
    (AMER ASSOC NEUROLOGICAL SURGEONS, 2022-01-01) Ulgen, Ege; Aras, Fuat Kaan; Cosgun, Erdal; Ersen-Danyeli, Ayca; Dincer, Alp; Usseli, M. Imre; Ozduman, Koray; Pamir, M. Necmettin
    OBJECTIVE Gliomas frequently involve the insula both primarily and secondarily by invasion. Despite the high connectivity of the human insula, gliomas do not spread randomly to or from the insula but follow stereotypical anatomical involvement patterns. In the majority of cases, these patterns correspond to the intrinsic connectivity of the limbic system, except for tumors with aggressive biology. On the basis of these observations, the authors hypothesized that these different involvement patterns may be correlated with distinct outcomes and analyzed these correlations in an institutional cohort. METHODS Fifty-nine patients who had undergone surgery for insular diffuse gliomas and had complete demographic, pre- and postoperative imaging, pathology, molecular genetics, and clinical follow-up data were included in the analysis (median age 37 years, range 21-71 years, M/F ratio 1.68). Patients with gliomatosis and those with only minor involvement of the insula were excluded. The presence of T2-hyperintense tumor infiltration was evaluated in 12 anatomical structures. Hierarchical biclustering was used to identify co-involved structures, and the findings were correlated with established functional anatomy knowledge. Overall survival was evaluated using Kaplan-Meier and Cox proportional hazards regression analysis (17 parameters). RESULTS The tumors involved the anterior insula (98.3\%), posterior insula (67.8\%), temporal operculum (47.5\%), amygdala (42.4\%), frontal operculum (40.7\%), temporal pole (39\%), parolfactory area (35.6\%), hypothalamus (23.7\%), hippocampus (16.9\%), thalamus (6.8\%), striatum (5.1\%), and cingulate gyrus (3.4\%). A mean 4.2 +/- 2.6 structures were involved. On the basis of hierarchical biclustering, 7 involvement patterns were identified and correlated with cortical functional anatomy (pure insular {[}11.9\%], olfactocentric {[}15.3\%], olfactoopercular {[}33.9\%], operculoinsular {[}15.3\%], striatoinsular {[}3.4\%], translimbic {[}11.9\%], and multifocal {[}8.5\%] patterns). Cox regression identified hippocampal involvement (p = 0.006) and postoperative tumor volume (p = 0.027) as significant negative independent prognosticators of overall survival and extent of resection (p = 0.015) as a significant positive independent prognosticator. CONCLUSIONS The study findings indicate that insular gliomas primarily involve the olfactocentric limbic girdle and that involvement in the hippocampocentric limbic girdle is associated with a worse prognosis.