Andres Morales La Madrid

Long‐term outcome of 4,040 children diagnosed with pediatric low‐grade gliomas: An analysis of the Surveillance Epidemiology and End Results (SEER) database

Children with pediatric low‐grade gliomas (PLGG) are known to have excellent 10‐year survival rates; however the outcomes of adult survivors of PLGG are unknown. We identified patients diagnosed with PLGG diagnosed between 1973 and 2008 through the Surveillance Epidemiology and End Results (SEER) database to examine outcomes of adult survivors of PLGG.

Secreted Protein Acidic and Rich in Cysteine Is a Matrix Scavenger Chaperone

Secreted Protein Acidic and Rich in Cysteine (SPARC) is one of the major non-structural proteins of the extracellular matrix (ECM) in remodeling tissues. The functional significance of SPARC is emphasized by its origin in the first multicellular organisms and its high degree of evolutionary conservation. Although SPARC has been shown to act as a critical modulator of ECM remodeling with profound effects on tissue physiology and architecture, no plausible molecular mechanism of its action has been proposed. In the present study, we demonstrate that SPARC mediates the disassembly and degradation of ECM networks by functioning as a matricellular chaperone. While it has low affinity to its targets inside the cells where the Ca2+ concentrations are low, high extracellular concentrations of Ca2+ activate binding to multiple ECM proteins, including collagens. We demonstrated that in vitro, this leads to the inhibition of collagen I fibrillogenesis and disassembly of pre-formed collagen I fibrils by SPARC at high Ca2+ concentrations. In cell culture, exogenous SPARC was internalized by the fibroblast cells in a time- and concentration-dependent manner. Pulse-chase assay further revealed that internalized SPARC is quickly released outside the cell, demonstrating that SPARC shuttles between the cell and ECM. Fluorescently labeled collagen I, fibronectin, vitronectin, and laminin were co-internalized with SPARC by fibroblasts, and semi-quantitative Western blot showed that SPARC mediates internalization of collagen I. Using a novel 3-dimentional model of fluorescent ECM networks pre-deposited by live fibroblasts, we demonstrated that degradation of ECM depends on the chaperone activity of SPARC. These results indicate that SPARC may represent a new class of scavenger chaperones, which mediate ECM degradation, remodeling and repair by disassembling ECM networks and shuttling ECM proteins into the cell. Further understanding of this mechanism may provide insight into the pathogenesis of matrix-associated disorders and lead to the novel treatment strategies.

Validation of a prognostic multi-gene signature in high-risk neuroblastoma using the high throughput digital NanoString nCounter™ system.

Microarray‐based molecular signatures have not been widely integrated into neuroblastoma diagnostic classification systems due to the complexities of the assay and requirement for high‐quality RNA. New digital technologies that accurately quantify gene expression using RNA isolated from formalin‐fixed paraffin embedded (FFPE) tissues are now available. In this study, we describe the first use of a high‐throughput digital system to assay the expression of genes in an “ultra‐high risk” microarray classifier in FFPE high‐risk neuroblastoma tumors. Customized probes corresponding to the 42 genes in a published multi‐gene neuroblastoma signature were hybridized to RNA isolated from 107 FFPE high‐risk neuroblastoma samples using the NanoString nCounter™ Analysis System. For classification of each patient, the Pearsons correlation coefficient was calculated between the standardized nCounter™ data and the molecular signature from the microarray data. We demonstrate that the nCounter™ 42‐gene panel sub‐stratified the high‐risk cohort into two subsets with statistically significantly different overall survival (p = 0.0027) and event‐free survival (p = 0.028). In contrast, none of the established prognostic risk markers (age, stage, tumor histology, MYCN status, and ploidy) were significantly associated with survival. We conclude that the nCounter™ System can reproducibly quantify expression levels of signature genes in FFPE tumor samples. Validation of this microarray signature in our high‐risk patient cohort using a completely different technology emphasizes the prognostic relevance of this classifier. Prospective studies testing the prognostic value of molecular signatures in high‐risk neuroblastoma patients using FFPE tumor samples and the nCounter™ System are warranted.

Targeting ALK: a promising strategy for the treatment of non-small cell lung cancer, non-Hodgkin’s lymphoma, and neuroblastoma

Anaplastic lymphoma kinase (ALK) is a tyrosine kinase receptor that affects a number of biological and biochemical functions through normal ligand-dependent signaling. It has oncogenic functions in a number of tumors including non-small cell lung cancer (NSCLC), anaplastic large cell lymphoma, and neuroblastoma when altered by translocation or amplification or mutation. On August 2011, a small molecule inhibitor against ALK, crizotinib, was approved for therapy against NSCLC with ALK translocations. As we determine the molecular heterogeneity of tumors, the potential of ALK as a relevant therapeutic target in a number of malignancies has become apparent. This review will discuss some of the tumor types with oncogenic ALK alterations. The activity and unique toxicities of crizotinib are described, along with potential mechanisms of resistance and new therapies beyond crizotinib.

Future Clinical Trials in DIPG: Bringing Epigenetics to the Clinic

In spite of major recent advances in diffuse intrinsic pontine glioma (DIPG) molecular characterization, this body of knowledge has not yet translated into better treatments. To date, more than 250 clinical trials evaluating radiotherapy along with conventional cytotoxic chemotherapy as well as newer biologic agents have failed to improve the dismal outcome when compared to palliative radiation alone. The biology of DIPG remained unknown until recently when the neurosurgical expertise along with the recognition by the scientific and clinical community of the importance of tissue sampling at diagnosis; ideally, in the context of a clinical trial and by trained neurosurgical teams to maximize patient safety. These pre-treatment tumor samples, and others coming from tissue obtained post-mortem, have yielded new insights into DIPG molecular pathogenesis. We now know that DIPG comprises a heterogeneous disease with variable molecular phenotypes, different from adult high-grade glioma, other non-pontine pediatric high-grade gliomas, and even between pontine gliomas. The discovery of histone H3.3 or H3.1 mutations has been an important step forward in understanding tumor formation, maintenance, and progression. Pharmacologic reversal of DIPG histone demethylation therefore offers an important potential intervention strategy for the treatment of DIPG. To date, clinical trials of newly diagnosed or progressive DIPG with epigenetic (histone) modifiers have been unsuccessful. Whether this failure represents limited activity of the agents used, their CNS penetration, redundant pathways within the tumor, or the possibility that histone mutations are necessary only to initiate DIPGs but not maintain their growth, suggest that a great deal still needs to be elucidated in both the underlying biology of these pathways and the drugs designed to target them. In this review, we will discuss the role of both epigenetic and genetic mutations within DIPG and the development of treatment strategies directed against the unique abnormalities present in this disease.

Opsoclonus-myoclonus and anti-Hu positive limbic encephalitis in a patient with neuroblastoma.

Opsoclonus‐myoclonus syndrome (OMS) is seen in 2–3% of children with neuroblastoma and is believed to be caused by an autoimmune process elicited by the tumor. Although long‐term neurologic sequelae are common in children with OMS, limbic encephalitis has not previously been reported. We report a child who developed limbic encephalitis associated with anti‐Hu antibodies, 6 years after her initial diagnosis of neuroblastoma and OMS. This case demonstrates that patients with neuroblastoma and OMS are at risk for developing new paraneoplastic symptoms years after their original diagnosis and emphasizes the need for careful long‐term follow‐up. Pediatr Blood Cancer 2012; 58: 472–474.

Two cases of localized neuroblastoma with multiple segmental chromosomal alterations and metastatic progression

Surgery alone is curative for most children with localized MYCN‐non‐amplified neuroblastoma. However, 10–15% will develop recurrent loco‐regional disease, and very rarely, patients will relapse metastatically. Currently, it is not possible to predict which child with localized, MYCN‐non‐amplified neuroblastoma will develop disseminated disease. We report two children who presented with favorable biology, localized neuroblastoma and subsequently relapsed with metastatic disease after treatment with surgery. Whole‐genome DNA copy number analyses performed on the diagnostic tumors identified 15 (case 1) and 8 (case 2) segmental chromosomal alterations. Further analysis of the prognostic value of whole‐genome analysis in children with localized neuroblastoma is warranted. Pediatr Blood Cancer 2013;60:332–335.

Central Versus Extraventricular Neurocytoma in Children: A Clinicopathologic Comparison and Review of the Literature.

Background: Central neurocytomas (CN) are rare pediatric CNS tumors most often with a benign clinical course. Occasionally, these tumors occur outside the ventricles and are called extraventricular neurocytomas (EVN). We present a retrospective institutional analysis of children with neurocytoma with prolonged follow-up. Procedure: Twelve patients were diagnosed with neurocytoma at our institution between 1993 and 2004. Results: Six patients were male and the median age at diagnosis was 12 years (1.5 to 16 y). Seven patients had CN and 5 had EVN. Presenting symptoms included headaches (67%), vomiting (50%), nausea (33%), seizures (33%), and mental status changes (25%). Obstructive hydrocephalus was present at diagnosis in 42% of the cases. Younger age and seizures were more common in patients with EVN. Gross total resection (GTR) was achieved in 42% (5/12) of the patients. Patients with GTR received no adjuvant therapy upfront; 1 patient subsequently had recurrence with leptomeningeal disease. Patients with subtotal resection received additional treatment: 1 underwent reoperation (GTR), 2 patients received focal radiation, 2 patients received adjuvant chemotherapy, and 2 patients received craniospinal irradiation followed by chemotherapy. The 20-year overall survival for this cohort was 83% with event free survival of 56%. Overall survival for CNs was 100%, versus 40% for EVN. Event free survival for CNs was 57% and 53% for the EVNs. An MIB-1 fraction >2% was associated with worse prognosis. Conclusions: Neurocytomas are rare brain tumors in children usually cured with GTR. Adjuvant focal radiation therapy and/or chemotherapy may improve disease control in cases with subtotal resection, but case-by-case analysis should be done. EVNs might be associated with worse outcome due to a higher proliferative index.

Diffuse Leptomeningeal Glioneural Tumour Simulating Tuberculous Meningitis in a 13-Year-Old Girl

increase in consistency, allowing the diagnosis of diffuse leptomeningeal glioneural tumour (DLGT) of childhood (Fig. 2). Ki67 was reported as 30%. IDH1 was negative. BRAF alterations in the tumour (tandem duplication and V600E mutation) were negative. Also, 1p deletion was not identified in the tumour (Fig. 2). The patient was started on vincristine and carboplatin as per COG 9952 protocol with good clinical and radiological response within 3 months of therapy (Fig. 3). Shortly after, the patient deteriorated clinically and radiologically. No response to vinblastine (6 mg/m2 weekly) or bevacizumab (10 mg/kg every 2 weeks) was observed, and the patient died of disease 7 months after diagnosis. DLGT of childhood is a rare disease characterized by the infiltration of the meninges by a diffuse neoplastic glial component without any evidence of intraparenchymal tumoural process in the central nervous system [1]. The aetiology is unknown. DLGT most commonly presents with signs and symptoms of meningitis and raised intracranial pressure. On CSF examination, an increase in protein level represents a major characteristic feature, and malignant cells are very infrequently detected. Brain A previously healthy 13-year-old girl presented with a few weeks of headache, nausea, and vomiting. Brain CT scan showed hydrocephalus with areas of periventricular hypodensity. On brain and spine MRI (Fig. 1) a marked thickening of the basal meninges with diffuse gadolinium enhancement was identified, predominantly along the anterior cranial fossa and the dorsal and lumbar spinal canal. No primary parenchymal lesion was observed. CSF examination revealed an elevated opening pressure of 45 cm of H2O and lymphocytosis, extremely highly elevated protein content (3 g/dL), and low glucose levels, with no malignant cells on cytological examination. Ophthalmoscopy showed a bilateral swelling of the optic nerves with a marked decrease in visual acuity. In the presence of hydrocephalus a ventriculoperitoneal shunt was placed. A presumptive diagnosis of tuberculosis meningitis was made and the patient was started on quadruple antituberculosis therapy. Bacterial, fungal, and mycobacterial cultures and a PCR assay of Mycobacterium tuberculosis were all negative. On this basis the antituberculosis therapy was stopped. A biopsy of leptomeninges was performed, characterized by a pearly opacified surface and Received: March 16, 2017 Accepted after revision: November 13, 2017 Published online: January 5, 2018

Immune Response Generated With the Administration of Autologous Dendritic Cells Pulsed With an Allogenic Tumoral Cell-Lines Lysate in Patients With Newly Diagnosed Diffuse Intrinsic Pontine Glioma

Background and objective Diffuse intrinsic pontine glioma (DIPG) is a lethal brainstem tumor in children. Dendritic cells (DCs) have T-cell stimulatory capacity and, therefore, potential antitumor activity for disease control. DCs vaccines have been shown to reactivate tumor-specific T cells in both clinical and preclinical settings. We designed a phase Ib immunotherapy (IT) clinical trial with the use of autologous dendritic cells (ADCs) pulsed with an allogeneic tumors cell-lines lysate in patients with newly diagnosed DIPG after irradiation (radiation therapy). Methods Nine patients with newly diagnosed DIPG met enrollment criteria. Autologous dendritic cell vaccines (ADCV) were prepared from monocytes obtained by leukapheresis. Five ADCV doses were administered intradermally during induction phase. In the absence of tumor progression, patients received three boosts of tumor lysate every 3 months during the maintenance phase. Results Vaccine fabrication was feasible in all patients included in the study. Non-specific KLH (9/9 patients) and specific (8/9 patients) antitumor response was identified by immunologic studies in peripheral blood mononuclear cells (PBMC). Immunological responses were also confirmed in the T lymphocytes isolated from the cerebrospinal fluid (CSF) of two patients. Vaccine administration resulted safe in all patients treated with this schema. Conclusion These preliminary results demonstrate that ADCV preparation is feasible, safe, and generate a DIPG-specific immune response detected in PBMC and CSF. This strategy shows a promising backbone for future schemas of combination IT.