Detection of N-Glycolyl GM3 Ganglioside in Neuroectodermal Tumors by Immunohistochemistry: An Attractive Vaccine Target for Aggressive Pediatric Cancer

The N-glycolylated ganglioside NeuGc-GM3 has been described in solid tumors such as breast carcinoma, nonsmall cell lung cancer, and melanoma, but is usually not detected in normal human cells. Our aim was to evaluate the presence of NeuGc-GM3 in pediatric neuroectodermal tumors by immunohistochemistry. Twenty-seven archival cases of neuroblastoma and Ewing sarcoma family of tumors (ESFT) were analyzed. Formalin-fixed, paraffin-embedded tumor samples were cut into 5 μm sections. The monoclonal antibody 14F7, a mouse IgG1 that specifically recognizes NeuGc-GM3, and a peroxidase-labeled polymer conjugated to secondary antibodies were used. Presence of NeuGc-GM3 was evident in 23 of 27 cases (85%), with an average of about 70% of positive tumors cells. Immunoreactivity was moderate to intense in most tumors, showing a diffuse cytoplasmic and membranous staining, although cases of ESFT demonstrated a fine granular cytoplasmic pattern. No significant differences were observed between neuroblastoma with and without NMYC oncogene amplification, suggesting that expression of NeuGc-GM3 is preserved in more aggressive cancers. Until now, the expression of N-glycolylated gangliosides in pediatric neuroectodermal tumors has not been investigated. The present study evidenced the expression of NeuGc-GM3 in a high proportion of neuroectodermal tumors, suggesting its potential utility as a specific target of immunotherapy

Recessive RYR1 mutations cause unusual congenital myopathy with prominent nuclear internalization and large areas of myofibrillar disorganization.

International audienceAIMS: To report the clinical, pathological and genetic findings in a group of patients with a previously not described phenotype of congenital myopathy due to recessive mutations in the gene encoding the type 1 muscle ryanodine receptor channel (RYR1). METHODS: Seven unrelated patients shared a predominant axial and proximal weakness of varying severity, with onset during the neonatal period, associated with bilateral ptosis and ophthalmoparesis, and unusual muscle biopsy features at light and electron microscopic levels. RESULTS: Muscle biopsy histochemistry revealed a peculiar morphological pattern characterized by numerous internalized myonuclei in up to 51% of fibres and large areas of myofibrillar disorganization with undefined borders. Ultrastructurally, such areas frequently occupied the whole myofibre cross section and extended to a moderate number of sarcomeres in length. Molecular genetic investigations identified recessive mutations in the ryanodine receptor (RYR1) gene in six compound heterozygous patients and one homozygous patient. Nine mutations are novel and four have already been reported either as pathogenic recessive mutations or as changes affecting a residue associated with dominant malignant hyperthermia susceptibility. Only two mutations were located in the C-terminal transmembrane domain whereas the others were distributed throughout the cytoplasmic region of RyR1. CONCLUSION: Our data enlarge the spectrum of RYR1 mutations and highlight their clinical and morphological heterogeneity. A congenital myopathy featuring ptosis and external ophthalmoplegia, concomitant with the novel histopathological phenotype showing fibres with large, poorly delimited areas of myofibrillar disorganization and internal nuclei, is highly suggestive of an RYR1-related congenital myopathy

The Netrin-1-Neogenin-1 signaling axis controls neuroblastoma cell migration via integrin-β1 and focal adhesion kinase activation

Neuroblastoma is a highly metastatic tumor that emerges from neural crest cell progenitors. Focal Adhesion Kinase (FAK) is a regulator of cell migration that binds to the receptor Neogenin-1 and is upregulated in neuroblastoma. Here, we show that Netrin-1 ligand binding to Neogenin-1 leads to FAK autophosphorylation and integrin β1 activation in a FAK dependent manner, thus promoting neuroblastoma cell migration. Moreover, Neogenin-1, which was detected in all tumor stages and was required for neuroblastoma cell migration, was found in a complex with integrin β1, FAK, and Netrin-1. Importantly, Neogenin-1 promoted neuroblastoma metastases in an immunodeficient mouse model. Taken together, these data show that Neogenin-1 is a metastasis-promoting protein that associates with FAK, activates integrin β1 and promotes neuroblastoma cell migration.This work was supported by the Comisión Nacional de Investigación Científica y Tecnológica [21130521]; Fondo Nacional de Desarrollo Científico y Tecnológico [1140697]; Fondo Nacional de Desarrollo Científico y Tecnológico [1180495]; Red Temática de Investigación Cooperativa en Cancer [RD12/0036/0027]; SAF [SAF2015-65175-R]; Red Temática de Investigación Cooperativa en Cancer [RD12/0036/0027]; PSG: Ministerio de Ciencia, Innovación y Universidades and FEDER funds (RTI2018-093596); JGC: Ministerio de Economía y Competitividad of Spain (PI17CIII/00013), Consejería de Educación, Juventud y Deporte, Comunidad de Madrid (P2017/BMD-3692), Fundación Oncohematología Infantil, AFANION, and Asociación Pablo Ugarte.S

Muscle histopathology in nebulin-related nemaline myopathy : ultrastrastructural findings correlated to disease severity and genotype

Peer reviewe

Skeletal Muscle Biopsy Analysis in Reducing Body Myopathy and Other Fhl1-related Disorders

FHL1 mutations have been associated with various disorders that include reducing body myopathy (RBM), Emery-Dreifuss-like muscular dystrophy, isolated hypertrophic cardiomyopathy, and some overlapping conditions. We report a detailed histochemical, immunohistochemical, electron microscopic, and immunoelectron microscopic analyses of muscle biopsies from 18 patients carrying mutations in FHL1: 14 RBM patients (Group 1), 3 Emery-Dreifuss muscular dystrophy patients (Group 2), and 1 patient with hypertrophic cardiomyopathy and muscular hypertrophy (Group 2). Group 1 muscle biopsies consistently showed RBs associated with cytoplasmic bodies. The RBs showed prominent FHL1 immunoreactivity whereas desmin, alpha B-crystallin, and myotilin immunoreactivity surrounded RBs. By electron microscopy, RBs were composed of electron-dense tubulofilamentous material that seemed to spread progressively between the myofibrils and around myonuclei. By immunoelectron microscopy, FHL1 protein was found exclusively inside RBs. Group 2 biopsies showed mild dystrophic abnormalities without RBs; only minor nonspecific myofibrillar abnormalities were observed under electron microscopy. Molecular analysis revealed missense mutations in the second FHL1 LIM domain in Group 1 patients and ins/del or missense mutations within the fourth FHL1 LIM domain in Group 2 patients. Our findings expand the morphologic features of RBM, clearly demonstrate the localization of FHL1 in RBs, and further illustrate major morphologic differences among different FHL1-related myopathies

Recurrent somatic chromosomal abnormalities in relapsed extraocular retinoblastoma

Most reports about copy number alterations (CNA) in retinoblastoma relate to patients with intraocular disease and features of children with extraocular relapse remain unknown, so we aimed to describe the CNA in this population. We evaluated 23 patients and 27 specimens from 4 centers. Seventeen cases had extraocular relapse after initial enucleation and six cases after an initial preservation attempt. We performed an analysis of CNA and BCOR gene alteration by SNP array (Single Nucleotide Polymorfism array), whole-exome sequencing, IMPACT panel and CGH array (Array-based comparative genomic hybridization). All cases presented CNA at a higher prevalence than those reported in previously published studies for intraocular cases. CNA previously reported for intraocular retinoblastoma were found at a high frequency in our cohort: gains in 1q (69.5%), 2p (60.9%) and 6p (86.9%), and 16q loss (78.2%). Other, previously less-recognized, CNA were found including loss of 11q (34.8%), gain of 17q (56.5%), loss of 19q (30.4%) and BCOR alterations were present in 72.7% of our cases. A high number of CNA including 11q deletions, 17q gains, 19q loss, and BCOR alterations, are more common in extraocular retinoblastoma. Identification of these features may be correlated with a more aggressive tumor warranting consideration for patient management.Fil: Aschero, María del Rosario. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Francis, Jasmine H.. Memorial Sloan-Kettering Cancer Center; Estados UnidosFil: Ganiewich, Daiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Gomez Gonzalez, Soledad. Hospital Sant Joan de Deu Barcelona; EspañaFil: Sampor, Claudia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Zugbi, Santiago. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ottaviani, Daniela. Universite de Paris; Francia. Institute Curie; Francia. Centre National de la Recherche Scientifique; FranciaFil: Lemelle, Lauriane. Universite de Paris; Francia. Institute Curie; Francia. Centre National de la Recherche Scientifique; FranciaFil: Mena, Marcela Daniela C. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Winter, Ursula Andrea. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Correa Llano, Genoveva. Hospital Sant Joan de Deu Barcelona; EspañaFil: Lamas, Gabriela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Lubieniecki, Fabiana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Szijan, Irene. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Genética y Biología Molecular; ArgentinaFil: Mora, Jaume. Hospital Sant Joan de Deu Barcelona; EspañaFil: Podhajcer, Osvaldo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Doz, François. Universite de Paris; Francia. Institute Curie; Francia. Centre National de la Recherche Scientifique; FranciaFil: Radvanyi, François. Universite de Paris; Francia. Institute Curie; Francia. Centre National de la Recherche Scientifique; FranciaFil: Abramson, David H.. Memorial Sloan-Kettering Cancer Center; Estados UnidosFil: Llera, Andrea Sabina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Schaiquevich, Paula Susana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lavarino, Cinzia. Hospital Sant Joan de Deu Barcelona; EspañaFil: Chantada, Guillermo Luis. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Hospital Sant Joan de Deu Barcelona; España. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Clinical, genomic, and pharmacological study of MYCN-amplified RB1 wild-type metastatic retinoblastoma

An uncommon subgroup of unilateral retinoblastomas with highly aggressive histological features, lacking aberrations in RB1 gene with high-level amplification of MYCN (MCYNampl RB1+/+) has only been described as intra-ocular cases treated with initial enucleation. Here, we present a comprehensive clinical, genomic, and pharmacological analysis of two cases of MCYNampl RB1+/+ with orbital and cervical lymph node involvement, but no central nervous system spread, rapidly progressing to fatal disease due to chemoresistance. Both patients showed in common MYCN high amplification and chromosome 16q and 17p loss. A somatic mutation in TP53, in homozygosis by LOH, and high chromosomal instability leading to aneuploidy was identified in the primary ocular tumor and sites of dissemination of one patient. High-throughput pharmacological screening was performed in a primary cell line derived from the lymph node dissemination of one case. This cell line showed resistance to broad spectrum chemotherapy consistent with the patient’s poor response but sensitivity to the synergistic effects of panobinostat–bortezomib and carboplatin–panobinostat associations. From these cells we established a cell line derived xenograft model that closely recapitulated the tumor dissemination pattern of the patient and served to evaluate whether triple chemotherapy significantly prolonged survival of the animals. We report novel genomic alterations in two cases of metastatic MCYNampl RB1+/+ that may be associated with chemotherapy resistance and in vitro/in vivo models that serve as basis for tailoring therapy in these cases.Fil: Zugbi, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Ganiewich, Daiana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Bhattacharyya, Arpita. Tata Memorial Hospital; IndiaFil: Aschero, María del Rosario. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ottaviani, Daniela. Centre National de la Recherche Scientifique; FranciaFil: Sampor, Claudia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Cafferata, Eduardo Gustavo Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Mena, Marcela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Sgroi, Mariana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Winter, Ursula Andrea. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Lamas, Gabriela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Suñol, Mariona. Hospital Sant Joan de Deu Barcelona; EspañaFil: Daroqui, Manuel. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Baialardo, Edgardo. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Salas, Beatriz. Hospital Asencio Villaroel; BoliviaFil: Das, Anirban. Tata Memorial Hospital; IndiaFil: Fandiño, Adriana Cristina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Francis, Jasmine H.. Memorial Sloan-kettering Cancer Center.; Estados UnidosFil: Lubieniecki, Fabiana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Lavarino, Cinzia. Hospital Sant Joan de Deu Barcelona; EspañaFil: Garippa, Ralph. Memorial Sloan-kettering Cancer Center.; Estados UnidosFil: Podhajcer, Osvaldo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Abramson, David. Memorial Sloan-kettering Cancer Center.; Estados UnidosFil: Radvanyi, François. Centre National de la Recherche Scientifique; FranciaFil: Chantada, Guillermo Luis. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Llera, Andrea Sabina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Schaiquevich, Paula Susana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Severe ACTA1-related nemaline myopathy: intranuclear rods, cytoplasmic bodies, and enlarged perinuclear space as characteristic pathological features on muscle biopsies.

peer reviewedNemaline myopathy (NM) is a muscle disorder with broad clinical and genetic heterogeneity. The clinical presentation of affected individuals ranges from severe perinatal muscle weakness to milder childhood-onset forms, and the disease course and prognosis depends on the gene and mutation type. To date, 14 causative genes have been identified, and ACTA1 accounts for more than half of the severe NM cases. ACTA1 encodes α-actin, one of the principal components of the contractile units in skeletal muscle. We established a homogenous cohort of ten unreported families with severe NM, and we provide clinical, genetic, histological, and ultrastructural data. The patients manifested antenatal or neonatal muscle weakness requiring permanent respiratory assistance, and most deceased within the first months of life. DNA sequencing identified known or novel ACTA1 mutations in all. Morphological analyses of the muscle biopsy specimens showed characteristic features of NM histopathology including cytoplasmic and intranuclear rods, cytoplasmic bodies, and major myofibrillar disorganization. We also detected structural anomalies of the perinuclear space, emphasizing a physiological contribution of skeletal muscle α-actin to nuclear shape. In-depth investigations of the nuclei confirmed an abnormal localization of lamin A/C, Nesprin-1, and Nesprin-2, forming the main constituents of the nuclear lamina and the LINC complex and ensuring nuclear envelope integrity. To validate the relevance of our findings, we examined muscle samples from three previously reported ACTA1 cases, and we identified the same set of structural aberrations. Moreover, we measured an increased expression of cardiac α-actin in the muscle samples from the patients with longer lifespan, indicating a potential compensatory effect. Overall, this study expands the genetic and morphological spectrum of severe ACTA1-related nemaline myopathy, improves molecular diagnosis, highlights the enlargement of the perinuclear space as an ultrastructural hallmark, and indicates a potential genotype/phenotype correlation

Intracranial Gliofibroma: A Case Report and Review of the Literature

Gliofibroma is a rare tumor with biphasic morphology, commonly occurring in the first two decades of life. Currently, the tumor is not listed as a distinct entity in the current World Health Organization (WHO) classification of central nervous system tumors. As its biological behavior, histogenesis, and prognostic factors are still debated, the aim of this paper was to describe a case of a gliofibroma and to update the data about these lesions. Hence, we present here clinical symptoms, pathological findings, and evolution observed in a child with gliofibroma. A 10-year-old girl with seizures was referred for study. Neuroimaging showed a hemispheric hyperdense tumor with little peritumoral edema and no mass effect. The tumor was totally removed. Histologically, the tumor consisted of a mixture of glial cells and collagen-rich stroma. Immunohistochemical examination revealed positive staining for GFAP, CD 99, S100, and vimentin. EMA staining showed a paranuclear dot pattern in only few cells in isolated areas. These findings of a glial component with collagenous stroma were consistent with a desmoplastic glioma. Because of the rarity of this entity, we believe it is important to report every case in order to adequately analyze and categorize the tumor in the next WHO classification

Stem-cell marker CD34, multidrug resistance proteins P-gp and BCRP in SEGA

The resistance of human malignancy to multiple chemotherapeutic agents remains a major obstacle in cancer therapy due to in part to increased expression of ATP-binding cassette (ABC) transporters gene family, including “multidrug resistance 1”, and “breast cancer resistant protein”. These proteins are differentially expressed during normal hematopoiesis with the highest levels in primitive bone marrow CD34 stem cell population, and similarly, it was also suggested to occur transiently during neurulation. Subependymal Giant Cell Astrocytoma (SEGA) is a periventricular-low-grade tumor usually associated with tuberous sclerosis complex. We previously described that several multidrug-resistance proteins are overexpressed in brain cortical tubers associated with refractory epilepsy; however, they have not been investigated in SEGA. From a previous reported study of 15 brain specimens of SEGA, 6 randomized cases were selected for the immunostaining with specific monoclonal antibodies to multidrug resistance 1, breast cancer resistant protein and CD34 stem-cell marker. Heterogeneous distributions for these markers were detected with differential immunostaining pattern, showing high immunoreactivity in SEGA cells far of vessels, and low or negative expression in SEGA cells near the vessels. This particular expression pattern of both ABCtransporters, and CD34 antigen could identify different stem-cell subset in SEGA