Search results for "MYCN"
showing 10 items of 23 documents
A g316a polymorphism in the ornithine decarboxylase gene promoter modulates mycn‐driven childhood neuroblastoma
2021
Simple Summary Neuroblastoma is a devasting childhood cancer in which multiple copies (amplification) of the cancer-causing gene MYCN strongly predict poor outcome. Neuroblastomas are reliant on high levels of cellular components called polyamines for their growth and malignant behavior, and the gene regulating polyamine synthesis is called ODC1. ODC1 is often coamplified with MYCN, and in fact is regulated by MYCN, and like MYCN is prognostic of poor outcome. Here we studied a naturally occurring genetic variant or polymorphism that occurs in the ODC1 gene, and used gene editing to demonstrate the functional importance of this variant in terms of ODC1 levels and growth of neuroblastoma cel…
CRISPR-Cas9 screen reveals a MYCN-amplified neuroblastoma dependency on EZH2.
2018
Pharmacologically difficult targets, such as MYC transcription factors, represent a major challenge in cancer therapy. For the childhood cancer neuroblastoma, amplification of the oncogene MYCN is associated with high-risk disease and poor prognosis. Here, we deployed genome-scale CRISPR-Cas9 screening of MYCN-amplified neuroblastoma and found a preferential dependency on genes encoding the polycomb repressive complex 2 (PRC2) components EZH2, EED, and SUZ12. Genetic and pharmacological suppression of EZH2 inhibited neuroblastoma growth in vitro and in vivo. Moreover, compared with neuroblastomas without MYCN amplification, MYCN-amplified neuroblastomas expressed higher levels of EZH2. ChIP…
Targeting MYCN in Pediatric and Adult Cancers
2021
The deregulation of theMYCfamily of oncogenes, includingc-MYC,MYCNandMYCLoccurs in many types of cancers, and is frequently associated with a poor prognosis. The majority of functional studies have focused onc-MYCdue to its broad expression profile in human cancers. The existence of highly conserved functional domains betweenMYCNandc-MYCsuggests thatMYCNparticipates in similar activities.MYCencodes a basic helix-loop-helix-leucine zipper (bHLH-LZ) transcription factor (TF) whose central oncogenic role in many human cancers makes it a highly desirable therapeutic target. Historically, as a TF, MYC has been regarded as “undruggable”. Thus, recent efforts focus on investigating methods to indi…
Influence of segmental chromosome abnormalities on survival in children over the age of 12 months with unresectable localised peripheral neuroblastic…
2014
Background: The prognostic impact of segmental chromosome alterations (SCAs) in children older than 1 year, diagnosed with localised unresectable neuroblastoma (NB) without MYCN amplification enrolled in the European Unresectable Neuroblastoma (EUNB) protocol is still to be clarified, while, for other group of patients, the presence of SCAs is associated with poor prognosis. Methods: To understand the role of SCAs we performed multilocus/pangenomic analysis of 98 tumour samples from patients enrolled in the EUNB protocol. Results: Age at diagnosis was categorised into two groups using 18 months as the age cutoff. Significant difference in the presence of SCAs was seen in tumours of patients…
Genome-wide promoter methylation analysis in neuroblastoma identifies prognostic methylation biomarkers.
2012
Background: Accurate outcome prediction in neuroblastoma, which is necessary to enable the optimal choice of risk-related therapy, remains a challenge. To improve neuroblastoma patient stratification, this study aimed to identify prognostic tumor DNA methylation biomarkers.Results: To identify genes silenced by promoter methylation, we first applied two independent genome-wide methylation screening methodologies to eight neuroblastoma cell lines. Specifically, we used re-expression profiling upon 5-aza-2'-deoxycytidine (DAC) treatment and massively parallel sequencing after capturing with a methyl-CpG-binding domain (MBD-seq). Putative methylation markers were selected from DAC-upregulated …
Expresión inmunohistoquímica de la proteína mycN y el estado del gen MYCN en tumores neuroblásticos
2007
Antecedentes: Los tumores neuroblásticos son de los tumores pediátricos más frecuentes. A pesar de su gran variedad genética, clínica e histopatológica, la amplificación del gen MYCN es siempre un indicador de mal pronóstico. Este oncogen codifica una proteína nuclear que se une al ADN y activa la transcripción de sus genes diana. Un aumento en el número de copias del gen no se corresponde siempre con sobreexpresión de su proteína. El valor pronóstico de la detección de la proteína es controvertido. Métodos: Se han analizado 220 muestras de NB. Mediante la técnica de FISH se ha establecido el estado del gen, mientras que la inmunohistoquímica ha permitido el estudio de la expresión de la pr…
Zvaigžņotā Debess: 2005, Vasara
2005
Contents: In memoriam Arturs Balklavs-Grīnhofs ; Parting Words to Arturs Balklavs ; List of Publications by Prof. Dr.phys. Arturs Balklavs-Grīnhofs ; Astronomy in 25 Years of Soviet Latvia ; Man in Space: Based on newspaper “Pravda” materials ; U.Dzērvītis. Centenary of the Theory of Relativity ; A.Balklavs. Gamma Emission from the Galactic Centre ; A.Alksnis, Z.Alksne. Fewer Brown Dwarfs, More Red Ones ; A.Alksnis. New Observations of the Eruptive Variable Star V838 Mon ; A.Balklavs. Cosmic Objects in Captivating Photos – 5 ; J. Freimanis. On Polarization of Continuous Solar Spectrum ; J.Jaunbergs. The Very First Contact with Titan ; A.Millers. Biological Effects of Cosmic Rays ; J.Jansons…
The genetic tumor background is an important determinant for heterogeneous MYCN ‐amplified neuroblastoma
2016
Amplification of MYCN is the signature genetic aberration of 20–25% of neuroblastoma and a stratifying marker associated with aggressive tumor behavior. The detection of heterogeneous MYCN amplification (hetMNA) poses a diagnostic dilemma due to the uncertainty of its relevance to tumor behavior. Here, we aimed to shed light on the genomic background which permits hetMNA in neuroblastoma and tied the occurrence to other stratifying markers and disease outcome. We performed SNP analysis using Affymetrix Cytoscan HD arrays on 63 samples including constitutional DNA, tumor, bone marrow and relapse samples of 26 patients with confirmed hetMNA by MYCN‐FISH. Tumors of patients ≤18m were mostly an…
Imbalance between genomic gain and loss identifies high-risk neuroblastoma patients with worse outcomes
2021
Survival in high-risk neuroblastoma (HR-NB) patients remains poor despite multimodal treatment. We aimed to identify HR-NB patients with worse outcomes by analyzing the genomic instability derived from segmental chromosomal aberrations. We calculated 3 genomic instability indexes for primary tumor SNP array profiles from 127 HR-NB patients: (1) Copy number aberration burden (%gainslength+%losseslength), (2) copy number load (CNL) (%gainslength-%losseslength) and (3) net genomic load (NGL) (%gainsamount-%lossesamount). Tumors were classified according to positive or negative CNL and NGL genomic subtypes. The impact of the genomic instability indexes on overall survival (OS) was assessed with…
Neuroblastoma after Childhood: Prognostic Relevance of Segmental Chromosome Aberrations, ATRX Protein Status, and Immune Cell Infiltration
2014
AbstractNeuroblastoma (NB) is a common malignancy in children but rarely occurs during adolescence or adulthood. This subgroup is characterized by an indolent disease course, almost uniformly fatal, yet little is known about the biologic characteristics. The aim of this study was to identify differential features regarding DNA copy number alterations, α-thalassemia/mental retardation syndrome X-linked (ATRX) protein expression, and the presence of tumor-associated inflammatory cells. Thirty-one NB patients older than 10 years who were included in the Spanish NB Registry were considered for the current study; seven young and middle-aged adult patients (range 18-60 years) formed part of the c…