Bernhard Radlwimmer

Publications of Bernhard Radlwimmer

• Expression of podoplanin in human astrocytic brain tumors is controlled by the PI3K-AKT-AP-1 signaling pathway and promoter methylation.

  Authors: Heike Peterziel, Julia Müller, Andreas Danner, Sebastian Barbus, Hai-Kun Liu, Bernhard Radlwimmer, Torsten Pietsch, Peter Lichter, Günther Schütz, Jochen Hess, Peter Angel

  Neuro-oncology. 03/2012; 14(4):426-39.

  Recently, we found strong overexpression of the mucin-type glycoprotein podoplanin (PDPN) in human astrocytic brain tumors, specifically in primary glioblastoma multiforme (GB). In the current study,Recently, we found strong overexpression of the mucin-type glycoprotein podoplanin (PDPN) in human astrocytic brain tumors, specifically in primary glioblastoma multiforme (GB). In the current study, we show an inverse correlation between PDPN expression and PTEN levels in primary human GB and glioma cell lines, and we report elevated PDPN protein levels in the subventricular zone of brain tissue sections of PTEN-deficient mice. In human glioma cells lacking functional PTEN, reintroduction of wild-type PTEN, inhibition of the PTEN downstream target protein kinase B/AKT, or interference with transcription factor AP-1 function resulted in efficient downregulation of PDPN expression. In addition, we observed hypoxia-dependent PDPN transcriptional control and demonstrated that PDPN expression is subject to negative transcriptional regulation by promoter methylation in human GB and in glioma cell lines. Treatment of PTEN-negative glioma cells with demethylating agents induced expression of PDPN. Together, our findings show that increased PDPN expression in human GB is caused by loss of PTEN function and activation of the PI3K-AKT-AP-1 signaling pathway, accompanied by epigenetic regulation of PDPN promoter activity. Silencing of PDPN expression leads to reduced proliferation and migration of glioma cells, suggesting a functional role of PDPN in glioma progression and malignancy. Thus, specific targeting of PDPN expression and/or function could be a promising strategy for the treatment of patients with primary GB.

• Microglia isolated from patients with glioma gain antitumor activities on poly (I:C) stimulation.

  Authors: Tim Kees, Jennifer Lohr, Johannes Noack, Rodrigo Mora, Georg Gdynia, Grischa Tödt, Aurélie Ernst, Bernhard Radlwimmer, Christine S Falk, Christel Herold-Mende, Anne Régnier-Vigouroux

  Neuro-oncology. 01/2012; 14(1):64-78.

  The role of microglia, the brain-resident macrophages, in glioma biology is still a matter of debate. Clinical observations and in vitro studies in the mouse model indicate that microglia andThe role of microglia, the brain-resident macrophages, in glioma biology is still a matter of debate. Clinical observations and in vitro studies in the mouse model indicate that microglia and macrophages that infiltrate the brain tumor tissue in high numbers play a tumor-supportive role. Here, we provide evidence that human microglia isolated from brain tumors indeed support tumor cell growth, migration, and invasion. However, after stimulation with the Toll-like receptor 3 agonist poly (I:C), microglia secrete factors that exerted toxic and suppressive effects on different glioblastoma cell lines, as assessed in cytotoxicity, migration, and tumor cell spheroid invasion assays. Remarkably, these effects were tumor-specific because the microglial factors impaired neither growth nor viability of astrocytes and neurons. Culture supernatants of tumor cells inhibited the poly (I:C) induction of this microglial M1-like, oncotoxic profile. Microglia stimulation before coculture with tumor cells circumvented the tumor-mediated suppression, as demonstrated by the ability to kill and phagocytose glioma cells. Our results show, for the first time to our knowledge, that human microglia exert tumor-supporting functions that are overridden by tumor-suppressing activities gained after poly (I:C) stimulation.

• The Wnt secretion protein Evi/Gpr177 promotes glioma tumourigenesis.

  Authors: Iris Augustin, Violaine Goidts, Angelika Bongers, Grainne Kerr, Gordon Vollert, Bernhard Radlwimmer, Christian Hartmann, Christel Herold-Mende, Guido Reifenberger, Andreas von Deimling, Michael Boutros

  EMBO molecular medicine. 12/2011; 4(1):38-51.

  Malignant astrocytomas are highly aggressive brain tumours with poor prognosis. While a number of structural genomic changes and dysregulation of signalling pathways in gliomas have been described,Malignant astrocytomas are highly aggressive brain tumours with poor prognosis. While a number of structural genomic changes and dysregulation of signalling pathways in gliomas have been described, the identification of biomarkers and druggable targets remains an important task for novel diagnostic and therapeutic approaches. Here, we show that the Wnt-specific secretory protein Evi (also known as GPR177/Wntless/Sprinter) is overexpressed in astrocytic gliomas. Evi/Wls is a core Wnt signalling component and a specific regulator of pan-Wnt protein secretion, affecting both canonical and non-canonical signalling. We demonstrate that its depletion in glioma and glioma-derived stem-like cells led to decreased cell proliferation and apoptosis. Furthermore, Evi/Wls silencing in glioma cells reduced cell migration and the capacity to form tumours in vivo. We further show that Evi/Wls overexpression is sufficient to promote downstream Wnt signalling. Taken together, our study identifies Evi/Wls as an essential regulator of glioma tumourigenesis, identifying a pathway-specific protein trafficking factor as an oncogene and offering novel therapeutic options to interfere with the aberrant regulation of growth factors at the site of production.

• An endogenous tumour-promoting ligand of the human aryl hydrocarbon receptor.

  Authors: Christiane A Opitz, Ulrike M Litzenburger, Felix Sahm, Martina Ott, Isabel Tritschler, Saskia Trump, Theresa Schumacher, Leonie Jestaedt, Dieter Schrenk, Michael Weller, Manfred Jugold, Gilles J Guillemin, Christine L Miller, Christian Lutz, Bernhard Radlwimmer, Irina Lehmann, Andreas von Deimling, Wolfgang Wick, Michael Platten

  Nature. 10/2011; 478(7368):197-203.

  Activation of the aryl hydrocarbon receptor (AHR) by environmental xenobiotic toxic chemicals, for instance 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin), has been implicated in a variety of cellularActivation of the aryl hydrocarbon receptor (AHR) by environmental xenobiotic toxic chemicals, for instance 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin), has been implicated in a variety of cellular processes such as embryogenesis, transformation, tumorigenesis and inflammation. But the identity of an endogenous ligand activating the AHR under physiological conditions in the absence of environmental toxic chemicals is still unknown. Here we identify the tryptophan (Trp) catabolite kynurenine (Kyn) as an endogenous ligand of the human AHR that is constitutively generated by human tumour cells via tryptophan-2,3-dioxygenase (TDO), a liver- and neuron-derived Trp-degrading enzyme not yet implicated in cancer biology. TDO-derived Kyn suppresses antitumour immune responses and promotes tumour-cell survival and motility through the AHR in an autocrine/paracrine fashion. The TDO-AHR pathway is active in human brain tumours and is associated with malignant progression and poor survival. Because Kyn is produced during cancer progression and inflammation in the local microenvironment in amounts sufficient for activating the human AHR, these results provide evidence for a previously unidentified pathophysiological function of the AHR with profound implications for cancer and immune biology.

• A gene signature distinguishing CD133hi from CD133- colorectal cancer cells: essential role for EGR1 and downstream factors.

  Authors: Aurélie Ernst, Maximilian Aigner, Susumu Nakata, Felix Engel, Magdalena Schlotter, Matthias Kloor, Karsten Brand, Steffen Schmitt, Gunnar Steinert, Nuh Rahbari, Moritz Koch, Bernhard Radlwimmer, Jürgen Weitz, Peter Lichter

  Pathology. 04/2011; 43(3):220-7.

  In colorectal cancer (CRC), CD133 expression is an independent prognostic marker associated with adverse clinical outcome. The CD133 epitope AC133 allowed isolating stem cells from normal andIn colorectal cancer (CRC), CD133 expression is an independent prognostic marker associated with adverse clinical outcome. The CD133 epitope AC133 allowed isolating stem cells from normal and cancerous tissues, although its use in colon was questioned. We aimed to identify differences between AC133 and AC133 cells. We analysed the gene expression profiles of EpCAM/CEA/AC133 and EpCAM/CEA/AC133 cells from primary CRC and liver metastasis tissues (n = 5). Immunohistochemistry confirmed these results in a validation set. We identified 68 genes differentially expressed between both populations, including genes of notorious importance in CRC pathogenesis, and several candidates not previously shown to play a major role in CRC. Notably, EGR1 belonged to the most highly expressed genes in AC133 cells. In the validation set, the presence of EGR1 and CD133 correlated (r = 0.625). Since EGR1 regulates Wnt through up-regulation of TCF4, which induces stem cell marker LGR5, the potential association between LGR5, EGR1 and CD133 was investigated. The presence of LGR5 correlated with the presence of EGR1 and CD133. Strong signals for LGR5 were detected throughout tumour invasion fronts. The study suggests a connection between CD133 and EGR1 and emphasises the importance of the EGR1/TCF4/CD133/LGR5 network in CRC.

• Molecular signatures classify astrocytic gliomas by IDH1 mutation status.

  Authors: Grischa Toedt, Sebastian Barbus, Marietta Wolter, Jörg Felsberg, Björn Tews, Frederic Blond, Michael C Sabel, Stefanie Hofmann, Natalia Becker, Christian Hartmann, Hiroko Ohgaki, Andreas von Deimling, Otmar D Wiestler, Meinhard Hahn, Peter Lichter, Guido Reifenberger, Bernhard Radlwimmer

  International journal of cancer. Journal international du cancer. 03/2011; 128(5):1095-103.

  To identify novel glioma-associated pathomechanisms and molecular markers, we performed an array-based comparative genomic hybridization analysis of 131 diffuse astrocytic gliomas, including 87To identify novel glioma-associated pathomechanisms and molecular markers, we performed an array-based comparative genomic hybridization analysis of 131 diffuse astrocytic gliomas, including 87 primary glioblastomas (pGBIV), 13 secondary glioblastomas (sGBIV), 19 anaplastic astrocytomas (AAIII) and 12 diffuse astrocytomas (AII). All tumors were additionally screened for IDH1 and IDH2 mutations. Expression profiling was performed for 74 tumors (42 pGBIV, 11 sGBIV, 13 AAIII, 8 AII). Unsupervised and supervised bioinformatic analyses revealed distinct genomic and expression profiles separating pGBIV from the other entities. Classifier expression signatures were strongly associated with the IDH1 gene mutation status. Within pGBIV, the rare subtype of IDH1 mutant tumors shared expression profiles with IDH1 mutant sGBIV and was associated with longer overall survival compared with IDH1 wild-type tumors. In patients with IDH1 wild-type pGBIV, PDGFRA gain or amplification as well as 19q gain were associated with patient outcome. Array-CGH analysis additionally revealed homozygous deletions of the FGFR2 gene at 10q26.13 in 2 pGBIV, with reduced FGFR2 mRNA levels being frequent in pGBIV and linked to poor outcome. In conclusion, we report that diffuse astrocytic gliomas can be separated into 2 major molecular groups with distinct genomic and mRNA profiles as well as IDH1 gene mutation status. In addition, our results suggest FGFR2 as a novel glioma-associated candidate tumor suppressor gene on the long arm of chromosome 10.

• Differential retinoic acid signaling in tumors of long- and short-term glioblastoma survivors.

  Authors: Sebastian Barbus, Björn Tews, Daniela Karra, Meinhard Hahn, Bernhard Radlwimmer, Nicolas Delhomme, Christian Hartmann, Jörg Felsberg, Dietmar Krex, Gabriele Schackert, Ramon Martinez, Guido Reifenberger, Peter Lichter

  Journal of the National Cancer Institute. 02/2011; 103(7):598-606.

  Although the prognosis of most glioblastoma patients is poor, 3%-5% patients show long-term survival of 36 months or longer after diagnosis. To study the differences in activation of biochemicalAlthough the prognosis of most glioblastoma patients is poor, 3%-5% patients show long-term survival of 36 months or longer after diagnosis. To study the differences in activation of biochemical pathways, we performed mRNA and protein expression analyses of primary glioblastoma tissues from 11 long-term survivors (LTS; overall survival ≥ 36 months) and 12 short-term survivors (STS; overall survival ≤ 6 months). The mRNA expression ratio of the retinoic acid transporters fatty acid-binding protein 5 (FABP5) and cellular retinoic acid-binding protein 2 (CRABP2), which regulate the differential delivery of retinoic acid to either antioncogenic retinoic acid receptors or prooncogenic nuclear receptor peroxisome proliferator-activated receptor delta, was statistically significantly higher in the tumor tissues of STS than those of LTS (median ratio in STS tumors = 3.64, 10th-90th percentile = 1.43-4.54 vs median ratio in LTS tumors = 1.42, 10th-90th percentile = -0.98 to 2.59; P < .001). High FABP5 protein expression in STS tumors was associated with highly proliferating tumor cells and activation of 3-phosphoinositide-dependent protein kinase-1 and v-akt murine thymoma viral oncogene homolog. The data suggest that retinoic acid signaling activates different targets in glioblastomas from LTS and STS. All statistical tests were two-sided.

• Mapping candidate regions and genes for congenital anomalies of the kidneys and urinary tract (CAKUT) by array-based comparative genomic hybridization.

  Authors: Stefanie Weber, Christina Landwehr, Miriam Renkert, Alexander Hoischen, Elke Wühl, Jonas Denecke, Bernhard Radlwimmer, Dieter Haffner, Franz Schaefer, Ruthild G Weber

  Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association. 01/2011; 26(1):136-43.

  Congenital anomalies of the kidneys and urinary tract (CAKUT) are frequently associated with malformations of other organs. In order to explore the role of DNA microimbalances in syndromal CAKUT, weCongenital anomalies of the kidneys and urinary tract (CAKUT) are frequently associated with malformations of other organs. In order to explore the role of DNA microimbalances in syndromal CAKUT, we applied genome-wide array-based comparative genomic hybridization (array-CGH) in 30 children with various CAKUT phenotypes and at least one additional extrarenal symptom. In three patients, causal imbalances were detected: In one patient with duplex kidney and vesico-ureteral reflux associated with extrarenal stigmata, a terminal 9.52 Mb gain in chromosomal band 2q37.1-q37.3 and a terminal 5.65 Mb loss in 7q36.2-q36.3 were detected, which were due to an unbalanced 2;7-translocation according to FISH analysis. A balanced 2;7-translocation was present in the unaffected mother. In another patient presenting with renal hypoplasia and proximal ureteric stenosis combined with mental retardation, macrocephaly and ear anomalies, a duplication of 2.73 Mb was detected in 1q21.1. The unaffected father had a 1.3 Mb gain in 1q21.1-q21.2 involving the distal part of the patient's gain, for which benign copy number variation was described. A third patient affected by dysplastic kidney with a strongly dilated ureter and extrarenal abnormalities exhibited a de novo loss of 13.38 Mb in 3q23-q25.1 including the AGTR1 gene. However, no AGTR1 mutations were identified in the remaining allele of this case or in 108 patients with isolated renal dysplasia/hypoplasia. In this study, 10% of patients with syndromic CAKUT were shown to carry DNA microimbalances, and four chromosomal regions presumably associated with the CAKUT phenotype were identified: 1q21.1, 2q37.1-q37.3, 3q23-q25.1 and 7q36.2-q36.3.

• Authors' reply.

  Authors: Daniel E Stange, Bernhard Radlwimmer

  Gut. 12/2010;

• Differentiation therapy exerts antitumor effects on stem-like glioma cells.

  Authors: Benito Campos, Feng Wan, Mohammad Farhadi, Aurélie Ernst, Felix Zeppernick, Katrin E Tagscherer, Rezvan Ahmadi, Jennifer Lohr, Christine Dictus, Georg Gdynia, Stephanie E Combs, Violaine Goidts, Burkhard M Helmke, Volker Eckstein, Wilfried Roth, Philipp Beckhove, Peter Lichter, Andreas Unterberg, Bernhard Radlwimmer, Christel Herold-Mende

  Clinical cancer research : an official journal of the American Association for Cancer Research. 05/2010; 16(10):2715-28.

  Stem-like tumor cells comprise a highly tumorigenic and therapy-resistant tumor subpopulation, which is believed to substantially influence tumor initiation and therapy resistance in glioma.Stem-like tumor cells comprise a highly tumorigenic and therapy-resistant tumor subpopulation, which is believed to substantially influence tumor initiation and therapy resistance in glioma. Currently, therapeutic, drug-induced differentiation is considered as a promising approach to eradicate this tumor-driving cell population; retinoic acid is well known as a potent modulator of differentiation and proliferation in normal stem cells. In glioma, knowledge about the efficacy of retinoic acid-induced differentiation to target the stem-like tumor cell pool could have therapeutic implications. Stem-like glioma cells (SLGC) were differentiated with all-trans retinoic acid-containing medium to study the effect of differentiation on angiogenesis, invasive growth, as well as radioresistance and chemoresistance of SLGCs. In vivo effects were studied using live microscopy in a cranial window model. Our data suggest that in vitro differentiation of SLGCs induces therapy-sensitizing effects, impairs the secretion of angiogenic cytokines, and disrupts SLGCs motility. Further, ex vivo differentiation reduces tumorigenicity of SLGCs. Finally, we show that all-trans retinoic acid treatment alone can induce antitumor effects in vivo. Altogether, these results highlight the potential of differentiation treatment to target the stem-like cell population in glioblastoma.

• The nuclear receptor tailless induces long-term neural stem cell expansion and brain tumor initiation.

  Authors: Hai-Kun Liu, Ying Wang, Thorsten Belz, Dagmar Bock, Andrea Takacs, Bernhard Radlwimmer, Sebastian Barbus, Guido Reifenberger, Peter Lichter, Günther Schütz

  Genes & development. 04/2010; 24(7):683-95.

  Malignant gliomas are the most common primary brain tumors, and are associated with frequent resistance to therapy as well as poor prognosis. Here we demonstrate that the nuclear receptor taillessMalignant gliomas are the most common primary brain tumors, and are associated with frequent resistance to therapy as well as poor prognosis. Here we demonstrate that the nuclear receptor tailless (Tlx), which in the adult is expressed exclusively in astrocyte-like B cells of the subventricular zone, acts as a key regulator of neural stem cell (NSC) expansion and brain tumor initiation from NSCs. Overexpression of Tlx antagonizes age-dependent exhaustion of NSCs in mice and leads to migration of stem/progenitor cells from their natural niche. The increase of NSCs persists with age, and leads to efficient production of newborn neurons in aged brain tissues. These cells initiate the development of glioma-like lesions and gliomas. Glioma development is accelerated upon loss of the tumor suppressor p53. Tlx-induced NSC expansion and gliomagenesis are associated with increased angiogenesis, which allows for the migration and maintenance of brain tumor stem cells in the perivascular niche. We also demonstrate that Tlx transcripts are overexpressed in human primary glioblastomas in which Tlx expression is restricted to a subpopulation of nestin-positive perivascular tumor cells. Our study clearly demonstrates how NSCs contribute to brain tumorgenesis driven by a stem cell-specific transcription factor, thus providing novel insights into the histogenesis and molecular pathogenesis of primary brain tumors.

• MYC High Level Gene Amplification Is a Distinctive Feature of Angiosarcomas after Irradiation or Chronic Lymphedema.

  Authors: Johanna Manner, Bernhard Radlwimmer, Peter Hohenberger, Katharina Mössinger, Stefan Küffer, Christian Sauer, Djeda Belharazem, Andreas Zettl, Jean-Michel Coindre, Christian Hallermann, Jörg Thomas Hartmann, Detlef Katenkamp, Kathrin Katenkamp, Patrick Schöffski, Raf Sciot, Agnieszka Wozniak, Peter Lichter, Alexander Marx, Philipp Ströbel

  The American journal of pathology. 12/2009;

  Angiosarcomas (AS) are rare vascular malignancies that arise either de novo as primary tumors or secondary to irradiation or chronic lymphedema. The cytogenetics of angiosarcomas are poorlyAngiosarcomas (AS) are rare vascular malignancies that arise either de novo as primary tumors or secondary to irradiation or chronic lymphedema. The cytogenetics of angiosarcomas are poorly characterized. We applied array-comparative genomic hybridization as a screening method to identify recurrent alterations in 22 cases. Recurrent genetic alterations were identified only in secondary but not in primary AS. The most frequent recurrent alterations were high level amplifications on chromosome 8q24.21 (50%), followed by 10p12.33 (33%) and 5q35.3 (11%). Fluorescence in situ hybridization analysis in 28 primary and 33 secondary angiosarcomas (31 tumors secondary to irradiation, 2 tumors secondary to chronic lymphedema) confirmed high level amplification of MYC on chromosome 8q24.21 as a recurrent genetic alteration found exclusively in 55% of AS secondary to irradiation or chronic lymphedema, but not in primary AS. Amplification of MYC did not predispose to high grade morphology or increased cell turnover. In conclusion, despite their identical morphology, secondary AS are genetically different from primary AS and are characterized by a high frequency of high level amplifications of MYC. This finding may have implications both for the diagnosis and treatment of these tumors.

• Genomic and expression profiling of glioblastoma stem cell-like spheroid cultures identifies novel tumor-relevant genes associated with survival.

  Authors: Aurélie Ernst, Stefanie Hofmann, Rezvan Ahmadi, Natalia Becker, Andrey Korshunov, Felix Engel, Christian Hartmann, Jörg Felsberg, Michael Sabel, Heike Peterziel, Moritz Durchdewald, Jochen Hess, Sebastian Barbus, Benito Campos, Anna Starzinski-Powitz, Andreas Unterberg, Guido Reifenberger, Peter Lichter, Christel Herold-Mende, Bernhard Radlwimmer

  Clinical cancer research : an official journal of the American Association for Cancer Research. 11/2009; 15(21):6541-50.

  PURPOSE: Glioblastoma spheroid cultures are enriched in tumor stem-like cells and therefore may be more representative of the respective primary tumors than conventional monolayer cultures. WePURPOSE: Glioblastoma spheroid cultures are enriched in tumor stem-like cells and therefore may be more representative of the respective primary tumors than conventional monolayer cultures. We exploited the glioma spheroid culture model to find novel tumor-relevant genes. EXPERIMENTAL DESIGN: We carried out array-based comparative genomic hybridization of spheroid cultures derived from 20 glioblastomas. Microarray-based gene expression analysis was applied to determine genes with differential expression compared with normal brain tissue and to nonneoplastic brain spheroids in glioma spheroid cultures. The protein expression levels of three candidates were determined by immunohistochemistry on tissue microarrays and correlated with clinical outcome. Functional analysis of PDPN was done. RESULTS: Genomic changes in spheroid cultures closely resembled those detected in primary tumors of the corresponding patients. In contrast, genomic changes in serum-grown monolayer cultures established from the same patients did not match well with the respective primary tumors. Microarray-based gene expression analysis of glioblastoma spheroid cultures identified a set of novel candidate genes being upregulated or downregulated relative to normal brain. Quantitative real-time PCR analyses of 8 selected candidate genes in 20 clinical glioblastoma samples validated the microarray findings. Immunohistochemistry on tissue microarrays revealed that expression of AJAP1, EMP3, and PDPN was significantly associated with overall survival of astrocytic glioma patients. Invasive capacity and RhoA activity were decreased in PDPN-silenced spheroids. CONCLUSION: We identified a set of novel candidate genes that likely play a role in glioblastoma pathogenesis and implicate AJAP1, EMP3, and PDPN as molecular markers associated with the clinical outcome of glioma patients.

• Recurrent copy number gain of transcription factor SOX2 and corresponding high protein expression in oral squamous cell carcinoma.

  Authors: Kolja Freier, Karl Knoepfle, Christa Flechtenmacher, Susanne Pungs, Frauke Devens, Grischa Toedt, Christof Hofele, Stefan Joos, Peter Lichter, Bernhard Radlwimmer

  Genes, chromosomes & cancer. 09/2009;

  Gene copy number aberrations are involved in oral squamous cell carcinoma (OSCC) development. To delineate candidate genes inside critical chromosomal regions, array-CGH was applied to 40 OSCCGene copy number aberrations are involved in oral squamous cell carcinoma (OSCC) development. To delineate candidate genes inside critical chromosomal regions, array-CGH was applied to 40 OSCC specimens using a microarray covering the whole human genome with an average resolution of 1 Mb. Gene copy number gains were predominantly found at 1q23 (9 cases), 3q26 (11), 5p15 (13), 7p11 (7), 8q24 (17), 11q13 (15), 14q32 (8), 19p13 (8), 19q12 (7), 19q13 (8), and 20q13 (9), whereas gene copy number losses were detected at 3p21-3p12 (15), 8p32 (11), 10p12 (8), and 18q21-q23 (10). Subsequent mRNA expression analyses by quantitative real time polymerase chain reaction found high mRNA expression of candidate genes SOX2 in 3q26.33, FSLT3 in 19p13.3, and CCNE1 in 19q12. Tissue microarray (TMA) analyses in a representative OSCC collection found gene copy number gain for SOX2 in 52% (115/223) and for CCNE1 in 31% (72/233) of the tumors. Immunohistochemical analyses on TMA sections of the corresponding proteins detected high expression of SOX2 in 18.1% (49/271) and of CyclinE1 in 23.3% (64/275) of tumors analyzed. These findings indicate that SOX2 and CCNE1 might be activated via gene copy number gain and participate in oral carcinogenesis. The combination of array-CGH with TMA analyses allows rapid pinpointing of novel promising candidate genes, which might be used as therapeutic stratification markers or target molecules for therapeutic interference. (c) 2009 Wiley-Liss, Inc.

• Rosetted glioneuronal tumor of the spine with overtly anaplastic histological features.

  Authors: Martin Scholz, Alexander Hoischen, Bernhard Radlwimmer, Ruthild G Weber, Albrecht Harders, Guido Reifenberger, Markus J Riemenschneider

  Acta neuropathologica. 06/2009; 117(5):591-3.

• Array-CGH in unclear syndromic nephropathies identifies a microdeletion in Xq22.3-q23.

  Authors: Alexander Hoischen, Christina Landwehr, Sarah Kabisch, Xiao-Qi Ding, Detlef Trost, Gerhard Stropahl, Marianne Wigger, Bernhard Radlwimmer, Ruthild Weber, Dieter Haffner

  Pediatric nephrology (Berlin, Germany). 06/2009;

  To investigate whether submicroscopic chromosomal deletions or duplications can be causative of unclear syndromic nephropathies, we analyzed ten patients with congenital abnormalities of the kidneyTo investigate whether submicroscopic chromosomal deletions or duplications can be causative of unclear syndromic nephropathies, we analyzed ten patients with congenital abnormalities of the kidney and urinary tract or glomerulopathies combined with important extrarenal anomalies by whole-genome array-based comparative genomic hybridization. In a 14-year-old girl presenting with hematuria, proteinuria, mental retardation (MR), sensorineural hearing loss, dysmorphisms, and epilepsy, we detected a microdeletion in chromosome Xq22.3-q23. This deletion was verified and characterized by fluorescence in situ hybridization and multiplex ligation-dependent probe amplification analyses, found to be de novo, uniallelic and 3.3 Mb in size. Electron microscopy of a kidney biopsy showed glomerular basement membrane thinning and segmental splitting of the lamina densa compatible with Alport syndrome. Cranial magnetic resonance and diffusion tensor imaging detected a severe neuronal migration disorder with double cortex formation and pronounced reduction of the fronto-occipital tract system. Thus, in one of ten patients with unclear syndromic nephropathies we identified a previously undescribed contiguous gene syndrome at Xq22.3-q23. The microdeletion contains the X-linked Alport syndrome gene COL4A5, the MR genes FACL4 and PAK3, and parts of the X-chromosomal lissencephaly gene DCX associated with double cortex formation in girls, MR, and epilepsy. The phenotype in our patient combines features of the Alport-MR contiguous gene syndrome with lissencephaly.

• Outcome prediction in pediatric medulloblastoma based on DNA copy-number aberrations of chromosomes 6q and 17q and the MYC and MYCN loci.

  Authors: Stefan Pfister, Marc Remke, Axel Benner, Frank Mendrzyk, Grischa Toedt, Jörg Felsberg, Andrea Wittmann, Frauke Devens, Nicolas U Gerber, Stefan Joos, Andreas Kulozik, Guido Reifenberger, Stefan Rutkowski, Otmar D Wiestler, Bernhard Radlwimmer, Wolfram Scheurlen, Peter Lichter, Andrey Korshunov

  Journal of clinical oncology : official journal of the American Society of Clinical Oncology. 05/2009; 27(10):1627-36.

  PURPOSE: Medulloblastoma is the most common malignant brain tumor in children. Current treatment decisions are based on clinical variables. Novel tumor-derived biomarkers may improve the riskPURPOSE: Medulloblastoma is the most common malignant brain tumor in children. Current treatment decisions are based on clinical variables. Novel tumor-derived biomarkers may improve the risk stratification of medulloblastoma patients. PATIENTS AND METHODS: A model for the molecular risk stratification was proposed from an array-based comparative genomic hybridization (array-CGH) screen (n = 80). Fluorescence in situ hybridization (FISH) analyses for chromosome arms 6q, 17p, and 17q and the MYC and MYCN loci were performed in an independent validation set (n = 260). Copy number aberrations were correlated with clinical, histologic, and survival data. RESULTS: Gain of 6q and 17q and genomic amplification of MYC or MYCN were each associated with poor outcome in the array-CGH study (n = 80). In contrast, all patients with 6q-deleted tumors survived. Given these findings, the following hierarchical molecular staging system was defined: (1) MYC/MYCN amplification, (2) 6q gain, (3) 17q gain, (4) 6q and 17q balanced, and (5) 6q deletion. The prognostic value of this staging system was investigated by FISH analysis (n = 260). The addition of molecular markers to clinical risk factors resulted in the identification of a large proportion of patients (72 of 260 patients; 30%) at high risk for relapse and death who would be considered standard risk by application of clinical variables alone. CONCLUSION: Genomic aberrations in medulloblastoma are powerful independent markers of disease progression and survival. By adding genomic markers to established clinical and histologic variables, outcome prediction can be substantially improved. Because the analyses can be conducted on routine paraffin-embedded material, it will be especially feasible to use this novel molecular staging system in large multicenter clinical trials.

• FARP2, HDLBP and PASK are downregulated in a patient with autism and 2q37.3 deletion syndrome.

  Authors: Bärbel Felder, Bernhard Radlwimmer, Axel Benner, Antoaneta Mincheva, Grischa Tödt, Kim S Beyer, Claudia Schuster, Sven Bölte, Gabriele Schmötzer, Sabine M Klauck, Fritz Poustka, Peter Lichter, Annemarie Poustka

  American journal of medical genetics. Part A. 05/2009;

  We describe a patient with autism and brachymetaphalangy, meeting criteria for 2q37 deletion syndrome (also called Albright Hereditary Osteodystrophy-like syndrome or Brachydactyly-Mental RetardationWe describe a patient with autism and brachymetaphalangy, meeting criteria for 2q37 deletion syndrome (also called Albright Hereditary Osteodystrophy-like syndrome or Brachydactyly-Mental Retardation syndrome, OMIM 600430). Our molecular cytogenetic studies, including array comparative genomic hybridization (aCGH) and fluorescence in situ hybridization (FISH), define the extent of the de novo deletion to a 3.5 Mb region on 2q37.3. Although a number of reports of patients with 2q37 deletion syndrome have been published, it remains unclear if gene expression and/or translation are altered by the deletion, thus contributing to the observed phenotypes. To address this question, we selected several candidate genes for the neuropsychiatric and skeletal anomalies found in this patient (autism and brachymetaphalangy). The deleted region in 2q37.3 includes the FERM, RhoGEF and pleckstrin domain protein 2 (FARP2), glypican 1 (GPC1), vigilin (HDLBP), kinesin family member 1A (KIF1A) and proline-alanine-rich STE20-related kinase (PASK), all of which are involved in skeletal or neural differentiation processes. Expression analyses of these genes were performed using RNA from lymphoblastoid cell lines of the patient and his family members. Here we demonstrate that three of these genes, FARP2, HDLBP, and PASK, are considerably downregulated in the patient's cell line. We hypothesize that haploinsufficiency of these genes may have contributed to the patient's clinical phenotype. (c) 2009 Wiley-Liss, Inc.

• High-resolution genomic profiling of childhood T-ALL reveals frequent copy-number alterations affecting the TGF-{beta} and PI3K-AKT pathways and deletions at 6q15-16.1 as a genomic marker for unfavorable early treatment response.

  Authors: Marc Remke, Stefan Pfister, Corinne Kox, Grischa Toedt, Natalia Becker, Axel Benner, Wiebke Werft, Stephen Breit, Shuangyou Liu, Felix Engel, Andrea Wittmann, Martin Zimmermann, Martin Stanulla, Martin Schrappe, Wolf-Dieter Ludwig, Claus R Bartram, Bernhard Radlwimmer, Martina U Muckenthaler, Peter Lichter, Andreas E Kulozik

  Blood. 05/2009;

  Precursor T-cell lymphoblastic leukemia (T-ALL) in children represents a clinical challenge, because relapses are usually fatal. It is thus necessary to identify high risk patients as early asPrecursor T-cell lymphoblastic leukemia (T-ALL) in children represents a clinical challenge, because relapses are usually fatal. It is thus necessary to identify high risk patients as early as possible to effectively individualize treatment. We aimed to define novel molecular risk markers in T-ALL, and performed array-based comparative genomic hybridization (array-CGH) and gene expression analyses in 73 patients. We show that DNA copy-number changes are common in T-ALL and affect 70/73 (96%) patients. Notably, genomic imbalances predicted to downregulate the TGF-beta or upregulate the PI3K-AKT pathways are identified in 25/73 (34%) and 21/73 (29%) of the patients, suggesting that these pathways play a key role in T-ALL leukemogenesis. Furthermore, we identified a deletion at 6q15-16.1 in 9/73 (12%) of the patients, which predicts poor early treatment response. This deletion includes the CASP8AP2 gene whose expression is also shown to be downregulated. The interaction of CASP8AP2 with CASP8 plays a crucial role in apoptotic regulation suggesting a likely functional link between the clinical effect of the deletion and the molecular mode of action. The data presented here thus implicate the TGF-beta and PI3K-AKT pathways in T-ALL leukemogenesis and identify a subgroup of T-ALL patients with CASP8AP2 deletions and poor early treatment response.

• Comprehensive Characterization of Genomic Aberrations in Gangliogliomas by CGH, Array-based CGH and Interphase FISH.

  Authors: Alexander Hoischen, Marion Ehrler, Jana Fassunke, Matthias Simon, Michael Baudis, Christina Landwehr, Bernhard Radlwimmer, Peter Lichter, Johannes Schramm, Albert J Becker, Ruthild G Weber

  Brain pathology (Zurich, Switzerland). 08/2008; 18(3):326-37.

  Gangliogliomas are generally benign neuroepithelial tumors composed of dysplastic neuronal and neoplastic glial elements. We screened 61 gangliogliomas [World Health Organization (WHO) grade I] forGangliogliomas are generally benign neuroepithelial tumors composed of dysplastic neuronal and neoplastic glial elements. We screened 61 gangliogliomas [World Health Organization (WHO) grade I] for genomic alterations by chromosomal and array-based comparative genomic hybridization (CGH). Aberrations were detected in 66% of gangliogliomas (mean +/- SEM = 2.5 +/- 0.5 alterations/tumor). Frequent gains were on chromosomes 7 (21%), 5 (16%), 8 (13%), 12 (12%); frequent losses on 22q (16%), 9 (10%), 10 (8%). Recurrent partial imbalances comprised the minimal overlapping regions dim(10)(q25) and enh(12)(q13.3-q14.1). Unsupervised cluster analysis of genomic profiles detected two major subgroups (group I: complete gain of 7 and additional gains of 5, 8 or 12; group II: no major recurring imbalances, mainly losses). A comparison with low-grade gliomas (astrocytomas WHO grade II) showed chromosome 5 gain to be significantly more frequent in gangliogliomas. Interphase fluorescence in situ hybridization (FISH) identified the aberrations to be contained in a subpopulation of glial but not in neuronal cells. Two gangliogliomas and their anaplastic recurrences (WHO grade III) were analyzed. Losses of CDKN2A/B and DMBT1 or a gain/amplification of CDK4 found in the anaplastic tumors were already present in the respective gangliogliomas by array CGH and interphase FISH. In summary, genomic profiling in a large series of gangliogliomas could distinguish genetic subgroups even in this low-grade tumor.