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Medulloblastoma (MB) comprises a group of heterogeneous paediatric embryonal neoplasms of the hindbrain with strong links to early development of the hindbrain 1–4. Mutations that activate Sonic hedgehog signalling lead to Sonic hedgehog MB in the upper rhombic lip (RL) granule cell lineage 5–8. By contrast, mutations that activate WNT signalling lead to WNT MB in the lower RL 9,10. However, little is known about the more commonly occurring group 4 (G4) MB, which is thought to arise in the unipolar brush cell lineage 3,4. Here we demonstrate that somatic mutations that cause G4 MB converge on the core binding factor alpha (CBFA) complex and mutually exclusive alterations that affect CBFA2T2, CBFA2T3, PRDM6, UTX and OTX2. CBFA2T2 is expressed early in the progenitor cells of the cerebellar RL subventricular zone in Homo sapiens, and G4 MB transcriptionally resembles these progenitors but are stalled in developmental time. Knockdown of OTX2 in model systems relieves this differentiation blockade, which allows MB cells to spontaneously proceed along normal developmental differentiation trajectories. The specific nature of the split human RL, which is destined to generate most of the neurons in the human brain, and its high level of susceptible EOMES +KI67 + unipolar brush cell progenitor cells probably predisposes our species to the development of G4 MB.

Supplementary Figure 5. Assessment of citric acid cycle activity by protein expression analysis of PDHE1a.

Supplementary Tables 1-6. Supplementary Table 1: Clinico-pathological demographics of CD133high and CD133low GBM; Supplementary Table 2: Positive and negative correlation probe sets present in CD133-signature; Supplementary Table 3: Drug targets acquired from CD133 gene signature connectivity map; Supplementary Table 4: qRT-PCR Primers; Supplementary Table 5: Genes used to complete network analysis; Supplementary Table 6: Molecular Subtypes of GBM samples used

Supplementary Table 1 - 7. Supplementary Table 1: Clinical and histopathological data associated with all spinal ependymomas analyzed in this study, along with molecular subgroup assignment; Supplementary Table 2: Table of all antibodies used in this study, their commercial sources, and dilutions used; Supplementary Table 3: Table of differentially expressed genes between spinal grade II and myxopapillary ependymoma; Supplementary Table 4: Summary of focal amplifications detected in spinal ependymoma by GISTIC2; Supplementary Table 5: Summary of focal deletions detected in spinal ependymoma by GISTIC2; Supplementary Table 6: List of significant pathways enriched by Gene Set Enrichment Analysis in spinal grade II ependymoma; Supplementary Table 7: List of significant pathways enriched by Gene Set Enrichment Analysis in spinal myxopapillary ependymoma

Supplementary Figures 1-6. Supplementary Figure 1: CD133 correlates patient outcome with GIC selfrenewal and proliferative capacities in human GBM; Supplementary Figure 2: Gene Set Enrichment Analysis (GSEA) results for embryonic stem cell gene sets in CD133high- and CD133low-signature REMBRANDT samples; Supplementary Figure 3: CD133+ GICs are resistant to most compounds selected from CD133 connectivity mapping; Supplementary Figure 4: Pyrvinium specifically targets CD133+ GICs; Supplementary Figure 5: Overexpression of CD133; Supplementary Figure 6: Gene Set Enrichment Analysis (GSEA) results of Pyrvinium or DMSO control treated GICs

Purpose: Clonal evolution of cancer may be regulated by determinants of stemness, specifically self-renewal, and current therapies have not considered how genetic perturbations or properties of stemness affect such functional processes. Glioblastoma-initiating cells (GICs), identified by expression of the cell surface marker CD133, are shown to be chemoradioresistant. In the current study, we sought to elucidate the functional role of CD133 in self-renewal and identify compounds that can specifically target this CD133+ treatment-refractory population.Experimental Design: Using gain/loss-of-function studies for CD133 we assessed the in vitro self-renewal and in vivo tumor formation capabilities of patient-derived glioblastoma cells. We generated a CD133 signature combined with an in silico screen to find compounds that target GICs. Self-renewal and proliferation assays on CD133-sorted samples were performed to identify the preferential action of hit compounds. In vivo efficacy of the lead compound pyrvinium was assessed in intracranial GIC xenografts and survival studies. Lastly, microarray analysis was performed on pyrvinium-treated GICs to discover core signaling events involved.Results: We discovered pyrvinium, a small-molecule inhibitor of GIC self-renewal in vitro and in vivo, in part through inhibition of Wnt/β-catenin signaling and other essential stem cell regulatory pathways. We provide a therapeutically tractable strategy to target self-renewing, chemoradioresistant, and functionally important CD133+ stem cells that drive glioblastoma relapse and mortality.Conclusions: Our study provides an integrated approach for the eradication of clonal populations responsible for cancer progression, and may apply to other aggressive and heterogeneous cancers. Clin Cancer Res; 21(23); 5324–37. ©2015 AACR.

Supplementary Figure 1. Unsupervised consensus hierarchical clustering and non-negative matrix factorization of 35 spinal ependymoma gene expression signatures from a rank 2 to 4 classification.

Supplementary Figure 2. Summary of focal copy number alterations detected by GISTIC2 in spinal Grade II and Myxopapillary Ependymoma.

Supplementary Figure 3. Analysis of HIF-1a expression in Spinal Grade II versus Myxopapillary Ependymoma in additional to single sample GSEA analysis of HIF1a transcriptional targets.

Supplementary Figure 4. Metabolic protein expression analysis supporting Figure 4 along with lactate measurements in normal spinal tissue, Grade II spinal ependymoma, and myxopapillary ependymoma.

Purpose: Myxopapillary ependymoma (MPE) is a distinct histologic variant of ependymoma arising commonly in the spinal cord. Despite an overall favorable prognosis, distant metastases, subarachnoid dissemination, and late recurrences have been reported. Currently, the only effective treatment for MPE is gross-total resection. We characterized the genomic and transcriptional landscape of spinal ependymomas in an effort to delineate the genetic basis of this disease and identify new leads for therapy.Experimental Design: Gene expression profiling was performed on 35 spinal ependymomas, and copy number profiling was done on an overlapping cohort of 46 spinal ependymomas. Functional validation experiments were performed on tumor lysates consisting of assays measuring pyruvate kinase M activity (PKM), hexokinase activity (HK), and lactate production.Results: At a gene expression level, we demonstrate that spinal grade II and MPE are molecularly and biologically distinct. These are supported by specific copy number alterations occurring in each histologic variant. Pathway analysis revealed that MPE are characterized by increased cellular metabolism, associated with upregulation of HIF1α. These findings were validated by Western blot analysis demonstrating increased protein expression of HIF1α, HK2, PDK1, and phosphorylation of PDHE1A. Functional assays were performed on MPE lysates, which demonstrated decreased PKM activity, increased HK activity, and elevated lactate production.Conclusions: Our findings suggest that MPE may be driven by a Warburg metabolic phenotype. The key enzymes promoting the Warburg phenotype: HK2, PKM2, and PDK are targetable by small-molecule inhibitors/activators, and should be considered for evaluation in future clinical trials for MPE. Clin Cancer Res; 21(16); 3750–8. ©2015 AACR.

Supplementary Figure 6. A schematic of the glycolytic pathway in myxopapillary ependymoma illustrating deregulation of proteins and metabolites and possible targets for therapeutic intervention.

Supplementary Figure and Table Legends. Legends describing in detail the data shown in supplementary figures and tables pertaining to this manuscript.

Sonic hedgehog medulloblastoma encompasses a clinically and molecularly diverse group of cancers of the developing central nervous system. Here, we use unbiased sequencing of the transcriptome across a large cohort of 250 tumors to reveal differences among molecular subtypes of the disease, and demonstrate the previously unappreciated importance of non-coding RNA transcripts. We identify alterations within the cAMP dependent pathway (GNAS, PRKAR1A) which converge on GLI2 activity and show that 18% of tumors have a genetic event that directly targets the abundance and/or stability of MYCN. Furthermore, we discover an extensive network of fusions in focally amplified regions encompassing GLI2, and several loss-of-function fusions in tumor suppressor genes PTCH1, SUFU and NCOR1. Molecular convergence on a subset of genes by nucleotide variants, copy number aberrations, and gene fusions highlight the key roles of specific pathways in the pathogenesis of Sonic hedgehog medulloblastoma and open up opportunities for therapeutic intervention., Sonic Hedgehog medulloblastoma (Shh-MB) comprises four subtypes each with distinct clinical traits. Here the authors characterize the genome, transcriptome, and methylome of Shh-MB subtypes, revealing a complex fusion landscape and the molecular convergence of MYCN and cAMP signaling pathways.

We describe an unusual leukoencephalopathy in a female who developed global language and memory difficulties as well as diffuse FLAIR lesions in the cerebral white matter (WM) ~ 30 months after bariatric surgery. She had no detectable nutritional deficiency. She died suddenly due to cardiovascular disease. The cerebral WM revealed perivascular T-cell infiltrations and strong immunoreactivity for the amyloid precursor protein limited to axons, without signs of myelin or neuronal injury. Unexplained WM lesions have been reported in post-bariatric-surgery patients. Our findings suggest that altered immunity and axonal dysfunction could be responsible for leukoencephalopathy in some patients undergoing bariatric procedures. .

SUMMARY Over the past decade, wingless-activated (WNT) medulloblastoma has been identified as a candidate for therapy de-escalation based on excellent survival; however, a paucity of relapses has precluded additional analyses of markers of relapse. To address this gap in knowledge, an international cohort of 93 molecularly confirmed WNT MB was assembled, where 5-year progression-free survival is 0.84 (95%, 0.763–0.925) with 15 relapsed individuals identified. Maintenance chemotherapy is identified as a strong predictor of relapse, with individuals receiving high doses of cyclophosphamide or ifosphamide having only one very late molecularly confirmed relapse (p = 0.032). The anatomical location of recurrence is metastatic in 12 of 15 relapses, with 8 of 12 metastatic relapses in the lateral ventricles. Maintenance chemotherapy, specifically cumulative cyclophosphamide doses, is a significant predictor of relapse across WNT MB. Future efforts to de-escalate therapy need to carefully consider not only the radiation dose but also the chemotherapy regimen and the propensity for metastatic relapses., Graphical Abstract, In Brief Nobre et al. analyze a clinically annotated cohort of 93 WNT-activated medulloblastoma using an integrated genomic approach. A maintenance chemotherapy regimen is the strongest predictor of relapse, and cumulative cyclophosphamide doses confer a reduced risk of relapse. Unlike other medulloblastoma subgroups, WNT-activated medulloblastoma recurs most frequently in the lateral ventricles.

Wingless-activated (WNT) medulloblastoma have been identified over the past decade as being a candidate for therapy de-escalation based on their excellent survival, however a paucity of relapses in any single cohort have precluded any additional analysis of markers of relapse. To address this gap in knowledge, an international cohort of 91 WNT-MB was assembled where we identified 14 relapsed cases where five-year progression free survival was 0.84 (95% 0.763-0.925). Maintenance chemotherapy was identified as a strong predictor of relapse, where no relapses were observed in cases receiving high doses of cyclophosphamide or ifosphamide (p=0.0026). The location of relapse was metastatic in 10/14 of relapses, with 7/10 metastatic relapses presenting along the ependymal lining in the lateral ventricles. Maintenance chemotherapy, specifically cumulative cyclophosphamide dose is a significant predictor of relapse across WNT-MB. Future efforts to de-escalate therapy need to carefully consider not only the radiation dose but also the chemotherapy regimen, and the propensity to metastatic relapses.

© The Author(s), under exclusive licence to Springer Nature Limited 2019, In cancer, recurrent somatic single-nucleotide variants-which are rare in most paediatric cancers-are confined largely to protein-coding genes1-3. Here we report highly recurrent hotspot mutations (r.3A>G) of U1 spliceosomal small nuclear RNAs (snRNAs) in about 50% of Sonic hedgehog (SHH) medulloblastomas. These mutations were not present across other subgroups of medulloblastoma, and we identified these hotspot mutations in U1 snRNA in only

Background The term “tumor-to-lesion metastasis” is an extension of “tumor-to-tumor metastasis,” which is a rare but well-documented phenomenon. Tumor metastasis to the meninges and/or central nervous system (CNS) is rare in patents with multiple sclerosis (MS), although MS lesions bear many similarities to the primary tumor microenvironment and metastatic niche. We present the first case of malignant tumor metastasis to MS lesions with immunophenotyping of inflammatory cells in the metastatic foci. Case Description A 45-year-old male patient with a 6-year history of MS and newly diagnosed lung carcinoma developed carcinoma metastases in the meninges and CNS, as well as into mixed active/inactive MS lesions. The carcinoma-hosting MS lesions exhibited abundant macrophages/microglia with ongoing demyelination but rare T cells. In comparison, a 46-year-old female patient with a 21-month history of MS and newly diagnosed gastric carcinoma was found to have leptomeningeal carcinomatosis and separate active MS lesions containing not only frequent macrophages/microglia but also T cells. Conclusions The carcinoma-hosting MS lesions are unlike typical active lesions but recapitulate the CNS metastatic niche. Our observations suggest that metastasis-hosting MS lesions might require a distinct immune microenvironment to be permissive to the seeding and growth of metastatic tumors.

Telomerase reverse transcriptase (TERT) promoter mutations were recently shown to drive telomerase activity in various cancer types, including medulloblastoma. However, the clinical and biological implications of TERT mutations in medulloblastoma have not been described. Hence, we sought to describe these mutations and their impact in a subgroup-specific manner. We analyzed the TERT promoter by direct sequencing and genotyping in 466 medulloblastomas. The mutational distributions were determined according to subgroup affiliation, demographics, and clinical, prognostic, and molecular features. Integrated genomics approaches were used to identify specific somatic copy number alterations in TERT promoter-mutated and wild-type tumors. Overall, TERT promoter mutations were identified in 21 % of medulloblastomas. Strikingly, the highest frequencies of TERT mutations were observed in SHH (83 %; 55/66) and WNT (31 %; 4/13) medulloblastomas derived from adult patients. Group 3 and Group 4 harbored this alteration in

Purpose: Myxopapillary ependymoma (MPE) is a distinct histologic variant of ependymoma arising commonly in the spinal cord. Despite an overall favorable prognosis, distant metastases, subarachnoid dissemination, and late recurrences have been reported. Currently, the only effective treatment for MPE is gross-total resection. We characterized the genomic and transcriptional landscape of spinal ependymomas in an effort to delineate the genetic basis of this disease and identify new leads for therapy. Experimental Design: Gene expression profiling was performed on 35 spinal ependymomas, and copy number profiling was done on an overlapping cohort of 46 spinal ependymomas. Functional validation experiments were performed on tumor lysates consisting of assays measuring pyruvate kinase M activity (PKM), hexokinase activity (HK), and lactate production. Results: At a gene expression level, we demonstrate that spinal grade II and MPE are molecularly and biologically distinct. These are supported by specific copy number alterations occurring in each histologic variant. Pathway analysis revealed that MPE are characterized by increased cellular metabolism, associated with upregulation of HIF1α. These findings were validated by Western blot analysis demonstrating increased protein expression of HIF1α, HK2, PDK1, and phosphorylation of PDHE1A. Functional assays were performed on MPE lysates, which demonstrated decreased PKM activity, increased HK activity, and elevated lactate production. Conclusions: Our findings suggest that MPE may be driven by a Warburg metabolic phenotype. The key enzymes promoting the Warburg phenotype: HK2, PKM2, and PDK are targetable by small-molecule inhibitors/activators, and should be considered for evaluation in future clinical trials for MPE. Clin Cancer Res; 21(16); 3750–8. ©2015 AACR.

We describe a 50-year-old man with a well-demarcated intra- and extrasellar lesion and clinical signs of a non-functioning pituitary adenoma. Neuropathological examination revealed tumor composed of non-pigmented spindle cells arranged in tightly packed nests separated by delicate vascular septae. There was no significant cellular atypia or mitotic activity, and Ki67-positive nuclei were present in less than 1% of cells. The neoplastic cells were positive for S-100 and vimentin, and negative for numerous cellular markers including HMB45, anti-melanoma cocktail antibodies, and Masson melanin stain. Electron microscopy revealed scattered cells with small numbers of premelanosomes, aiding in the correct diagnosis of an amelanotic melanocytoma. This is the first case report of entirely amelanotic melanocytoma of meninges, and in a very unique location. BRAF was negative supporting the diagnosis of intracranial origin of the tumor. Approximately 2 years after subtotal resection and stereotactic radiosurgery the patient is alive and well with a non-progressive residual tumor. .

We describe an atypical teratoid rhabdoid tumor (AT/RT) with a component of low-grade and anaplastic rhabdoid meningioma in a 7-year-old child. The AT/RT was uniformly negative for INI1 and displayed immunoreactivity for vimentin, P53, CD99, cytokeratins with AE1/AE3 antibodies, epithelial membrane antigen, β-catenin, smooth muscle actin, E-cadherin, and S-100 protein. AT/RT was continuous, with small foci of recognizable low-grade and anaplastic meningioma. The low-grade meningioma was INI1 positive with scattered INI1-negative nuclei, whereas the remaining tumor components were INI1 negative. A recurrent tumor 6 months after partial resection contained only INI1-negative AT/RT. This case supports the hypothesis that rare examples of AT/RT may emerge from a preexisting “parent” neoplasm as a result of a second hit mutation.

BackgroundStatins have recently been reported to cause a rare autoimmune inflammatory and/or necrotic myopathy that begins or persists after drug cessation.MethodsWe report on 26 patients seen at a neuromuscular centre between 2005 and 2011 who demonstrated muscle weakness/myalgias and creatine kinase elevations during or after statin treatment with continuation of signs and symptoms despite statin withdrawal.ResultsAll patients were treated with immunosuppressive therapy with good response; all improved biochemically and 86% improved clinically. Sixty-five percent of patients who attempted to taper off immunosuppressive therapy relapsed. We report on a novel finding whereby five of the seven patients who underwent multiple biopsies throughout their disease demonstrated a transformation of their histological diagnosis, with four progressing from having myofibre necrosis with minimal or no inflammation to a diagnosis of polymyositis.ConclusionsThis study offers preliminary evidence that statin-associated necrotizing myopathy and statin-associated polymyositis may not be separate entities but are part of the same pathophysiological spectrum. Both entities respond well to immunosuppression.

Summary Merkel cell carcinoma is an aggressive neuroendocrine tumor occasionally demonstrating aberrant differentiation to other epithelial and nonepithelial cell lines. We describe a case of Merkel cell carcinoma displaying unique patterns of differentiation in the primary focus and brain metastasis. The skin primary was almost uniformly small cell carcinoma positive for epithelial and neuroendocrine markers, with a few glial fibrillary acidic protein– and cytokeratin 20–positive cells. The neoplasm contained giant cells immunoreactive for neurofilament and negative for epithelial markers. The neck lymph node metastasis was a typical neuroendocrine Merkel cell carcinoma positive for cytokeratin 20. A solitary dural intracranial metastasis displayed features of aggressive ganglioneuroblastoma, expressing many neuronal antigens with no evidence of glial or epithelial differentiation. After total gross resection, the tumor recurred within 3 months, and the patient developed skeletal metastases and died 6 months after craniotomy.

An 84-year-old man with rheumatoid arthritis (RA) treated with methotrexate, developed progressive confusion and cerebellar symptoms, and died approximately 2 months later. Neuropathological examination revealed progressive multifocal leukoencephalopathy (PML) involving the cerebellum and brainstem. The affected tissues displayed intense infiltrations by CD8+ T-cells and microglia. JC virus was localized in oligodendroglia and cerebellar granule cells. This case illustrates unusual localization of inflammatory PML in a patient with RA treated with methotrexate.

While molecular subgrouping has revolutionized medulloblastoma classification, the extent of heterogeneity within subgroups is unknown. Similarity network fusion (SNF) applied to genome-wide DNA methylation and gene expression data across 763 primary samples identifies very homogeneous clusters of patients, supporting the presence of medulloblastoma subtypes. After integration of somatic copy-number alterations, and clinical features specific to each cluster, we identify 12 different subtypes of medulloblastoma. Integrative analysis using SNF further delineates group 3 from group 4 medulloblastoma, which is not as readily apparent through analyses of individual data types. Two clear subtypes of infants with Sonic Hedgehog medulloblastoma with disparate outcomes and biology are identified. Medulloblastoma subtypes identified through integrative clustering have important implications for stratification of future clinical trials.

We report a childhood case of thalamic atypical extraventricular neurocytoma that progressed to highly anaplastic ganglioglioma after 8 years of dormancy after subtotal resection and chemotherapy. The neurocytoma displayed immunoreactivity only for synaptophysin, β-catenin, S100, and CD56. The ganglioglioma acquired strong immunoreactivity for chromogranin, glial fibrillary acidic protein, neuron-specific enolase, and p53 and showed a very high proliferation rate approaching 50% in some areas. Tumor transformation was associated with overexpression of components of the sonic hedgehog and Wnt developmental signaling pathways, which are known to regulate tumor-initiating cells in malignant brain neoplasms.

The brain of a 5-year-old boy with Schinzel-Giedion syndrome displayed a cobblestone appearance of orbital and lateral aspects of frontal lobes due to widespread glioneuronal meningeal heterotopia. Meningeal heterotopia consisted of scattered neurons, neurofilament positive axons, and myelinated fibers accompanied by striking astrocytic gliosis. The underlying cortex showed gaps in the pial basal lamina, distorted neuronal layering, and focal polymicrogyria. The number of capillaries appeared increased throughout the brain. Mild hydrocephalus was associated with a slight atrophy of corpus callosum as well as villous hyperplasia and marked stromal degeneration of the choroid plexus. Our findings suggest that Schinzel-Giedion syndrome may represent One more entity within enlarging spectrum of lissencephalic cortical dysplasia syndromes.

SummaryDespite the histological similarity of ependymomas from throughout the neuroaxis, the disease likely comprises multiple independent entities, each with a distinct molecular pathogenesis. Transcriptional profiling of two large independent cohorts of ependymoma reveals the existence of two demographically, transcriptionally, genetically, and clinically distinct groups of posterior fossa (PF) ependymomas. Group A patients are younger, have laterally located tumors with a balanced genome, and are much more likely to exhibit recurrence, metastasis at recurrence, and death compared with Group B patients. Identification and optimization of immunohistochemical (IHC) markers for PF ependymoma subgroups allowed validation of our findings on a third independent cohort, using a human ependymoma tissue microarray, and provides a tool for prospective prognostication and stratification of PF ependymoma patients.

Introduction: Bergstrom needle muscle biopsies have been used by exercise physiologists for over 35 years but have been less accepted by neuromuscular clinicians due to size concerns. Methods: We retrospectively reviewed over 13,500 muscle Bergstrom needle biopsies done over a 21-year period to determine sampling success, patient/subject experience, and complications. We compared sample yield between two different needles (Bergstrom vs. UCH), with and without suction modifications. Results: Needle biopsies adequate for histology and enzymology were obtainable from the vastus lateralis, deltoid, biceps brachii, soleus, and medial gastrocnemius muscles, with a success rate of >99.9% and a minor complication rate of 0.15%. Approximately 450 muscle fibers were submitted for histologic assessment; suction modification and use of the Bergstrom vs. UCH needle were associated with larger sample size (P < 0.05). Conclusions: The suction-modified Bergstrom needle muscle biopsy technique is safe and provides an adequate sample size for histologic, ultrastructural, DNA, and enzyme analysis. Muscle Nerve, 2011

a McMaster University, Department of Medicine, Hamilton, Ontario, Canada b University of Ottawa, Department of Epidemiology and Community Medicine, Faculty of Medicine, Ottawa, Ontario, Canada c McMaster University, Department of Pathology and Molecular Medicine, Hamilton, Ontario, Canada d Stephenson Cardiovascular Magnetic Resonance Centre, University of Calgary, Alberta, Canada e Universite de Sherbrooke, Department of Cardiology, Quebec, Canada f McMaster University, Department of Medicine, Division of Cardiology, Hamilton, Ontario, Canada

Recurrent mutations in chromatin modifiers are specifically prevalent in adolescent or adult patients with Sonic hedgehog-associated medulloblastoma (SHH MB). Here, we report that mutations in the acetyltransferase CREBBP have opposing effects during the development of the cerebellum, the primary site of origin of SHH MB. Our data reveal that loss of Crebbp in cerebellar granule neuron progenitors (GNPs) during embryonic development of mice compromises GNP development, in part by downregulation of brain-derived neurotrophic factor (Bdnf). Interestingly, concomitant cerebellar hypoplasia was also observed in patients with Rubinstein-Taybi syndrome, a congenital disorder caused by germline mutations of CREBBP. By contrast, loss of Crebbp in GNPs during postnatal development synergizes with oncogenic activation of SHH signaling to drive MB growth, thereby explaining the enrichment of somatic CREBBP mutations in SHH MB of adult patients. Together, our data provide insights into time-sensitive consequences of CREBBP mutations and corresponding associations with human diseases.

We describe a pediatric case of primary angiosarcoma of the brain displaying striking intravascular papillary pattern, consistent with the "Dabska tumor," often in continuity with a massive, multifocal intravascular papillary endothelial hyperplasia. The tumor contained small hemangioma and obliterated dysplastic arteries as well as very large thin-walled veins. The surrounding brain tissue showed scattered telangiectasias, conglomerates of calcified dysplastic arteries, old hemorrhages and gliosis. Colocalization of these lesions suggests the development of a papillary angiosarcoma in the pre-existing vascular malformation. Although never reported, the possibility of a malignant transformation of endothelial papillary hyperplasia also should be considered in this case.

Although meningiomas represent the most common class of tumors of the central nervous system, the molecular events underlying their genesis and development are still not well defined, and therapeutic approaches based on the genetics of these tumors are currently lacking. In the present study we have used the immunoblotting technique to show that the p16INK4A, Cdk6 and pRB proteins are differentially expressed in primary meningioma cells with 20-, 30- and 36-fold difference between the lowest and the highest levels of each protein, respectively. In addition, we present evidence that the level of the anti-apoptosis survivin protein is high in these benign tumors. Moreover, the annexin V-associated flow cytometry technique was used to show that 60% of meningioma cell cultures underwent apoptosis in response to both γ-rays and cisplatin, and 50% of these cells exhibited significant sensitivity to hydroxyurea. These agents triggered apoptosis through the mitochondrial pathway, by increasing the Bax/Bcl-2 ratio. Interestingly, the induction of apoptosis following radiation and cisplatin was significant in all cells that expressed low levels of p16INK4A, Cdk6 and pRB proteins. These data shed more light on the molecular biology of meningioma cells and suggest that survivin and proteins of the RB pathway could play a determinant role in the development and the treatment of meningiomas.

Macrophagic myofasciitis is a novel, “inflammatory myopathy” described after a variety of vaccinations, almost exclusively in adults. We examined the relevance of histological findings of this myopathy to the clinical presentation in pediatric patients. Muscle biopsies from 8 children (7 months to 6 years old) with histological features of macrophagic myofasciitis were reviewed and correlated with the clinical manifestations. Patients underwent quadriceps muscle biopsy for suspected mitochondrial disease (4 patients), spinal muscular atrophy (2 patients), myoglobinuria (1 patient), and hypotonia with motor delay (1 patient). All biopsies showed identical granulomas composed of periodic acid-Schiff—positive and CD68-positive macrophages. Characteristic aluminum hydroxide crystals were identified by electron microscopy in 2 cases. The biopsy established diagnoses other than macrophagic myofasciitis in 5 patients: spinal muscular atrophy (2), Duchenne muscular dystrophy (1), phospho-glycerate kinase deficiency (1), and cytochrome c oxidase deficiency (1). Three children with manifestations and/or a family history of mitochondrial disease had otherwise morphologically normal muscle. All children had routine vaccinations between 2 months and 1 year before the biopsy, with up to 11 intramuscular injections, including the biopsy sites. There was no correlation between histological findings of macrophagic myofasciitis in biopsies and the clinical symptoms. We believe that macrophagic myofasciitis represents a localized histological hallmark of previous immunization with the aluminum hydroxide adjuvants contained in vaccines, rather than a primary or distinct inflammatory muscle disease.

Although meningiomas represent the most common class of tumors of the central nervous system, the molecular events underlying their genesis and development are still not well defined. In the present study we have used the immuno-blotting technique to study the expression level of the tumor suppressor proteins p53, p21 and PTEN in primary meningioma cells. We have also studied the induction of p21 and p53 in response to both UV light and gamma-rays. We present evidence that the p53/p21-dependent gamma-ray signaling pathway is defective in 5 out of 8 (62%) of these cells. Furthermore, we have shown that the tumor suppressor p21, p53 and PTEN proteins are differently expressed in these cells, with up to 40-folds difference between the lowest and the highest levels of each protein. These results suggest that the tumor suppressors p53/p21 signaling pathway and PTEN play important roles in the development of benign meningiomas.

We describe the clinical, radiological and pathological findings of concurrent, congenital leptomeningeal arteriovenous malformation with hemangioma diagnosed in a newborn by prenatal and immediately postnatal magnetic resonance imaging. Vascular abnormalities were accompanied by massive arachnoidal cell hyperplasia reminiscent of meningioma.To the best of our knowledge, this is the first case of such a lesion reported in the literature.

Objective: To identify the gene and specific mutation underlying hyaline body myopathy in the family studied.Methods: A microsatellite-based whole genome scan was performed. Linkage analysis assumed autosomal dominant inheritance and equal allele frequencies. A candidate gene approach within the linked interval and direct sequencing were used for mutation detection.Results: Initial analysis indicated a maximum lod score of 3.01 at D14S1280. High-density mapping surrounding the linked locus was performed. Multipoint analysis showed that the linked region with a maximum lod score of 3.01 extended from D14S742 to D14S608 with a peak non-parametric linkage (NPL) score of 3.75 at D14S608. The myosin heavy chain genes MYH6 and MYH7 map to the region between D14S742 and D14S1280. Sequence analysis of the coding regions of MYH7 revealed an A→T transversion at nucleotide position 25596 (M57965) resulting in a histidine-to-leucine amino acid change at residue 1904 (H1904L).Conclusion: Pathogenicity of the MYH7 H1904L mutation most likely results from disruption of myosin heavy chain assembly or stability of the sarcomeric protein. The MYH7 tail domain mutation results in an inclusion body myopathy with an apparent absence of hypertrophic cardiomyopathy usually associated with mutations of this gene.

Hemangiomas are customarily described as low-grade vascular tumors most often located in the head and neck, but on rare occasions occurring in the intradural space of the spine. The different subtypes of hemangiomas can be distinguished histologically as capillary, cavernous, or mixed types. We describe a rare case of a mixed capillary–cavernous extramedullary intradural hemangioma of the thoracic spinal cord, mimicking meningioma radiologically.

Purpose: Clonal evolution of cancer may be regulated by determinants of stemness, specifically self-renewal, and current therapies have not considered how genetic perturbations or properties of stemness affect such functional processes. Glioblastoma-initiating cells (GICs), identified by expression of the cell surface marker CD133, are shown to be chemoradioresistant. In the current study, we sought to elucidate the functional role of CD133 in self-renewal and identify compounds that can specifically target this CD133+ treatment-refractory population. Experimental Design: Using gain/loss-of-function studies for CD133 we assessed the in vitro self-renewal and in vivo tumor formation capabilities of patient-derived glioblastoma cells. We generated a CD133 signature combined with an in silico screen to find compounds that target GICs. Self-renewal and proliferation assays on CD133-sorted samples were performed to identify the preferential action of hit compounds. In vivo efficacy of the lead compound pyrvinium was assessed in intracranial GIC xenografts and survival studies. Lastly, microarray analysis was performed on pyrvinium-treated GICs to discover core signaling events involved. Results: We discovered pyrvinium, a small-molecule inhibitor of GIC self-renewal in vitro and in vivo, in part through inhibition of Wnt/β-catenin signaling and other essential stem cell regulatory pathways. We provide a therapeutically tractable strategy to target self-renewing, chemoradioresistant, and functionally important CD133+ stem cells that drive glioblastoma relapse and mortality. Conclusions: Our study provides an integrated approach for the eradication of clonal populations responsible for cancer progression, and may apply to other aggressive and heterogeneous cancers. Clin Cancer Res; 21(23); 5324–37. ©2015 AACR.