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1.
Nat Commun ; 12(1): 1881, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767157

RESUMO

To achieve the very high oncoprotein levels required to drive the malignant state cancer cells utilise the ubiquitin proteasome system to upregulate transcription factor levels. Here our analyses identify ALYREF, expressed from the most common genetic copy number variation in neuroblastoma, chromosome 17q21-ter gain as a key regulator of MYCN protein turnover. We show strong co-operativity between ALYREF and MYCN from transgenic models of neuroblastoma in vitro and in vivo. The two proteins form a nuclear coactivator complex which stimulates transcription of the ubiquitin specific peptidase 3, USP3. We show that increased USP3 levels reduce K-48- and K-63-linked ubiquitination of MYCN, thus driving up MYCN protein stability. In the MYCN-ALYREF-USP3 signal, ALYREF is required for MYCN effects on the malignant phenotype and that of USP3 on MYCN stability. This data defines a MYCN oncoprotein dependency state which provides a rationale for future pharmacological studies.


Assuntos
Carcinogênese/patologia , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/patologia , Proteínas Nucleares/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Cromossomos Humanos Par 17/genética , Variações do Número de Cópias de DNA/genética , Células HEK293 , Humanos , Camundongos , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Proteínas Nucleares/genética , Prognóstico , Interferência de RNA , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética , Transcrição Genética/genética , Ativação Transcricional/genética , Proteases Específicas de Ubiquitina/genética , Ubiquitinação/fisiologia
2.
Gen Physiol Biophys ; 40(1): 17-29, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33655888

RESUMO

Neuroblastoma (NB) is an extracranial solid malignancy in childhood. More and more studies have demonstrated that circRNAs are essential regulators of various tumors. This study conducted to explore the role and mechanism of circular RNA CUT-like homeobox 1 (circCUX1) in NB. The levels of circCUX1, miR-338-3p and plant homeodomain finger protein 20 (PHF20) were detected by qRT-PCR or Western blot. Cell proliferation and apoptosis were evaluated by colony formation assay, flow cytometry and Western blot analysis. Cell migration and invasion were examined via transwell assay. Glycolysis was expressed by measuring the extracellular acidification rate (ECAR). The interaction among circCUX1, miR-338-3p and PHF20 were validated by dual-luciferase reporter assay and RNA Immunoprecipitation assay. Besides, xenograft experiment was performed to assess tumor growth in vivo. circCUX1 and PHF20 were up-regulated, while miR-338-3p was down-regulated in NB tissues and cells. Knockdown of circCUX1 suppressed the progression and glycolysis of NB cells. circCUX1 triggered NB progression and glycolysis by regulating miR-338-3p. Additionally, down-regulation of miR-338-3p promoted NB progression and glycolysis via targeting PHF20. Moreover, circCUX1 sponged miR-338-3p to regulate PHF20 expression. Furthermore, circCUX1 silencing hindered tumor growth in vivo. circCUX1 depletion suppressed tumor progression and glycolysis in NB by regulating miR-338-3p/PHF20 axis, suggesting a potential biomarker for NB treatment.


Assuntos
MicroRNAs , Neuroblastoma , Linhagem Celular Tumoral , Criança , Proteínas de Ligação a DNA , Regulação Neoplásica da Expressão Gênica , Glicólise , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neuroblastoma/genética , Fatores de Transcrição
3.
J Vis Exp ; (169)2021 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-33779609

RESUMO

Zebrafish has emerged as an important animal model to study human diseases, especially cancer. Along with the robust transgenic and genome editing technologies applied in zebrafish modeling, the ease of maintenance, high-yield productivity, and powerful live imaging altogether make the zebrafish a valuable model system to study metastasis and cellular and molecular bases underlying this process in vivo. The first zebrafish neuroblastoma (NB) model of metastasis was developed by overexpressing two oncogenes, MYCN and LMO1, under control of the dopamine-beta-hydroxylase (dßh) promoter. Co-overexpressed MYCN and LMO1 led to the reduced latency and increased penetrance of neuroblastomagenesis, as well as accelerated distant metastasis of tumor cells. This new model reliably reiterates many key features of human metastatic NB, including involvement of clinically relevant and metastasis-associated genetic alterations; natural and spontaneous development of metastasis in vivo; and conserved sites of metastases. Therefore, the zebrafish model possesses unique advantages to dissect the complex process of tumor metastasis in vivo.


Assuntos
Neuroblastoma/genética , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Peixe-Zebra
4.
Medicine (Baltimore) ; 100(9): e24920, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33655954

RESUMO

BACKGROUND: Previous studies have investigated the prognostic role of programmed death ligand 1 (PD-L1) expression in patients with neuroblastoma, while the results are still controversial. Therefore, we conducted a meta-analysis to clarify the relationship between the expression of PD-L1 and the prognosis of neuroblastoma. METHODS: Search electronic databases include PubMed, Cochrane, Embase, Scopus and Web of Science, and the search time is set to build the database until January 2021. Hazard ratio (HR) and 95% confidence interval (CI) were used to analyze the included results. Meta-analysis was performed using Stata 15.0 software. RESULTS: This review will be disseminated in print by peer-review. CONCLUSION: The study will provide updated evidence for the evaluation of whether the expression of PD-L1 is associated with poor prognosis in patients with neuroblastoma. ETHICS AND DISSEMINATION: The private information from individuals will not be published. This systematic review also should not damage participants' rights. Ethical approval is not available. The results may be published in a peer-reviewed journal or disseminated in relevant conferences. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/FBCY6.


Assuntos
Antígeno B7-H1/genética , DNA de Neoplasias/genética , Regulação Neoplásica da Expressão Gênica , Neuroblastoma/genética , Antígeno B7-H1/biossíntese , Morte Celular/genética , Sobrevivência Celular , Humanos , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Prognóstico
6.
Mol Med Rep ; 23(4)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33537818

RESUMO

Neuroblastoma (NB) is considered a highly prevalent extracranial solid tumor in young children, and the upregulation of N­myc proto­oncogene (MYCN) is closely associated with the late stages of NB and poor prognostic outcomes. The current study was designed to evaluate the effects of exosomal microRNA (miRNA/miR)­17­5p from MYCN­amplified NB cells on the proliferative and migratory potential of non­MYCN amplified NB cells. miR­17­5p was found to activate the PI3K/Akt signaling cascade by targeting PTEN, and the overexpression of miR­17­5p was found to promote cellular migration and proliferation in vitro. Further experimentation revealed that the elevated expression of miR­17­5p in SK­N­BE(2) cell­derived exosomes significantly promoted the proliferative and migratory capacities of SH­SY5Y cells by inhibiting PTEN. Collectively, these findings demonstrated that miR­17­5p derived from MYCN­amplified NB cell exosomes promoted the migration and proliferation of non­MYCN amplified cells, highlighting an exosome­associated malignant role for miR­17­5p.


Assuntos
Movimento Celular , Proliferação de Células , Exossomos/metabolismo , Amplificação de Genes , MicroRNAs/metabolismo , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/metabolismo , RNA Neoplásico/metabolismo , Linhagem Celular Tumoral , Exossomos/genética , Exossomos/patologia , Humanos , MicroRNAs/genética , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Neuroblastoma/patologia , RNA Neoplásico/genética
7.
Nucleic Acids Res ; 49(5): 2509-2521, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33555349

RESUMO

The paucity of recurrent mutations has hampered efforts to understand and treat neuroblastoma. Alternative splicing and splicing-dependent RNA-fusions represent mechanisms able to increase the gene product repertoire but their role in neuroblastoma remains largely unexplored. Here we investigate the presence and possible roles of aberrant splicing and splicing-dependent RNA-fusion transcripts in neuroblastoma. In addition, we attend to establish whether the spliceosome can be targeted to treat neuroblastoma. Through analysis of RNA-sequenced neuroblastoma we show that elevated expression of splicing factors is a strong predictor of poor clinical outcome. Furthermore, we identified >900 primarily intrachromosomal fusions containing canonical splicing sites. Fusions included transcripts from well-known oncogenes, were enriched for proximal genes and in chromosomal regions commonly gained or lost in neuroblastoma. As a proof-of-principle that these fusions can generate altered gene products, we characterized a ZNF451-BAG2 fusion, producing a truncated BAG2-protein which inhibited retinoic acid induced differentiation. Spliceosome inhibition impeded neuroblastoma fusion expression, induced apoptosis and inhibited xenograft tumor growth. Our findings elucidate a splicing-dependent mechanism generating altered gene products in neuroblastoma and show that the spliceosome is a potential target for clinical intervention.


Assuntos
Chaperonas Moleculares/genética , Proteínas Mutantes Quiméricas/genética , Neuroblastoma/genética , Processamento de RNA , Spliceossomos/efeitos dos fármacos , Aminoaciltransferases/metabolismo , Animais , Apoptose , Diferenciação Celular , Linhagem Celular Tumoral , Feminino , Fusão Gênica , Proteínas de Choque Térmico HSC70/metabolismo , Humanos , Camundongos Nus , Chaperonas Moleculares/metabolismo , Proteínas Mutantes Quiméricas/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Deleção de Sequência , Fatores de Transcrição/metabolismo , Proteínas tau/metabolismo
8.
Zhonghua Zhong Liu Za Zhi ; 43(1): 118-125, 2021 Jan 23.
Artigo em Chinês | MEDLINE | ID: mdl-33472324

RESUMO

Objective: To investigate the effect of pentraxin 3 (PTX3) on the proliferation, invasion and drug resistance of pediatric neuroblastoma cells and its mechanism. Methods: si-RNA (si-RNA group), si-PTX3 (si-PTX3 group), siRNA+ pcDNA3.1 (siRNA+ pcDNA3.1 group), si-PTX3+ pcDNA3.1 (si-PTX3+ pcDNA3.1 group), siRNA+ pcDNA3.1-Toll-like receptor 4 (siRNA+ pcDNA3.1-TLR4 group) and si-PTX3+ pcDNA3.1-TLR4 (si-PTX3+ pcDNA3.1-TLR4 group) were transfected into SH-SY5Y cells. Collected 32 cases of tumor tissue and cancerous tissue in children with childhood neuromaternal cells who were treated at Zhumadian center hospital from July 2016 to August 2019. Real-time fluorescent quantitative polymerase chain (RT-qPCR) reaction and immunohistochemistry experiments were used to detect the protein expressions of PTX3 in neuroblastoma tissues and normal tissues. 5-Ethynyl-2'-deoxyuridine (EdU) was used to detect the proliferation effect of PTX3 on neuroblastoma cell SH-SY5Y. Western blot experiment was used to detect the protein expression levels of vascular endothelial growth factor (VEGF), resistance-related proteins including P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP-1), and invasion-related protein matrix metalloproteinase-1 (MMP-1). Results: PTX3 mRNA expressions in neuroblastoma tissues were 0.87±0.07, higher than 0.13±0.06 of normal tissues, and the differences were statistically significant (P<0.05), The expression of the immunohistochemistry test PTX3 protein was consistent with the qRT-PCR results. Compared with the si-RNA group (0.95±0.08; 1.02±0.10), the mRNA and protein expressions of PTX3 in the si-PTX3 group (0.25±0.05; 0.45±0.66) decreased, the differences were statistically significant (all P<0.05). The number of EdU positive cells, invasion rate, VEGF, MMP-1, P-gp and MRP-1 protein expressions in si-RNA group were (31.86±1.86)%, (28.12±2.96)%, (0.58±0.07), (0.44±0.06), (0.46±0.08) and (0.51±0.05), respectively, higher than (19.73±1.22)%, (8.45±1.06)%, (0.25±0.05), (0.19±0.03), (0.19±0.06) and (0.16±0.07) in si-PTX3 group, and the differences were statistically significant (all P<0.05). The Number of EdU positive cells [(19.49±1.68)%], invasion rate [(8.48±1.36)%], VEGF protein expression (0.10±0.15), P-gp (0.18±0.07) , TLR4 (0.45±0.06), p-p65 (0.25±0.05) protein expressions in si-PTX3+ pcDNA3.1 group were relatively lower compared with siRNA+ pcDNA3.1 group [(38.21±2.67)%, (26.39±2.14)%, 0.49±0.05, 0.52±0.06, 0.93±0.14 and 0.82±0.06] (all P<0.05). The number of EdU-positive cells [(62.73±5.18)%], invasion rate [(50.45±3.25)%], VEGF protein expression (2.17±0.17), P-gp (2.15±0.16), TLR4 (2.68±0.16), p-p65 (2.48±0.13) protein expressions in the siRNA+ pcDNA3.1-TLR4 group increased compared with siRNA+ pcDNA3.1 group (all P<0.05). Conclusions: Inhibition of PTX3 can inhibit the proliferation and invasion of neuroblastoma cells SH-SY5Y, and reduce drug resistance. Its mechanism may be achieved by regulating the TLR4/NF-κB signaling pathway. This result can provide a new perspective for pediatric neuroblasts tumor diagnosis and clinical treatment.


Assuntos
NF-kappa B , Neuroblastoma , Proteína C-Reativa , Proliferação de Células , Criança , Resistência a Medicamentos , Humanos , NF-kappa B/metabolismo , Neuroblastoma/genética , Componente Amiloide P Sérico , Transdução de Sinais , Receptor 4 Toll-Like/genética , Fator A de Crescimento do Endotélio Vascular/genética
9.
Nat Cell Biol ; 23(1): 99-108, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33398178

RESUMO

Detection of endogenous signals and precise control of genetic circuits in the natural context are essential to understand biological processes. However, the tools to process endogenous information are limited. Here we developed a generalizable endogenous transcription-gated switch that releases single-guide RNAs in the presence of an endogenous promoter. When the endogenous transcription-gated switch is coupled with the highly sensitive CRISPR-activator-associated reporter we developed, we can reliably detect the activity of endogenous genes, including genes with very low expression (<0.001 relative to Gapdh; quantitative-PCR analysis). Notably, we could also monitor the transcriptional activity of typically long non-coding RNAs expressed at low levels in living cells using this approach. Together, our method provides a powerful platform to sense the activity of endogenous genetic elements underlying cellular functions.


Assuntos
Células-Tronco Embrionárias Murinas/metabolismo , Neuroblastoma/genética , Neuroblastoma/metabolismo , Regiões Promotoras Genéticas , RNA Guia/metabolismo , RNA Longo não Codificante/metabolismo , RNA Mensageiro/metabolismo , Animais , Sistemas CRISPR-Cas , Células HEK293 , Humanos , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Neuroblastoma/patologia , RNA Guia/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genética
10.
Nat Cell Biol ; 23(1): 40-48, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33420492

RESUMO

Loss of the fragile X protein FMRP is a leading cause of intellectual disability and autism1,2, but the underlying mechanism remains poorly understood. We report that FMRP deficiency results in hyperactivated nonsense-mediated mRNA decay (NMD)3,4 in human SH-SY5Y neuroblastoma cells and fragile X syndrome (FXS) fibroblast-derived induced pluripotent stem cells (iPSCs). We examined the underlying mechanism and found that the key NMD factor UPF1 binds directly to FMRP, promoting FMRP binding to NMD targets. Our data indicate that FMRP acts as an NMD repressor. In the absence of FMRP, NMD targets are relieved from FMRP-mediated translational repression so that their half-lives are decreased and, for those NMD targets encoding NMD factors, increased translation produces abnormally high factor levels despite their hyperactivated NMD. Transcriptome-wide alterations caused by NMD hyperactivation have a role in the FXS phenotype. Consistent with this, small-molecule-mediated inhibition of hyperactivated NMD, which typifies iPSCs derived from patients with FXS, restores a number of neurodifferentiation markers, including those not deriving from NMD targets. Our mechanistic studies reveal that many molecular abnormalities in FMRP-deficient cells are attributable-either directly or indirectly-to misregulated NMD.


Assuntos
Proteína do X Frágil de Retardo Mental/genética , Síndrome do Cromossomo X Frágil/patologia , Deleção de Genes , Neuroblastoma/patologia , Degradação do RNAm Mediada por Códon sem Sentido , Transcriptoma , Estudos de Casos e Controles , Células Cultivadas , Fibroblastos/metabolismo , Fibroblastos/patologia , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neurônios/metabolismo , Neurônios/patologia , RNA-Seq , Transativadores
11.
Arch Pathol Lab Med ; 145(2): 214-221, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33501494

RESUMO

CONTEXT.­: Several countries of the Central America and Caribbean region have been sharing regional neuroblastoma (NB) treatment guidelines. However, there is no standardization in the diagnosis, subclassification, or tumor biology to aid in the risk stratification of these patients. OBJECTIVE.­: To examine the histology and assess the accuracy of the local pathology reports; to evaluate the usefulness of manual MYCN immunohistochemistry (IHC); and to use NB as a model to identify the needs to establish a central pathology review (CPR) program in this region. DESIGN.­: A retrospective CPR of specimens derived from patients with a diagnosis of NB and treated under the regional NB guidelines between 2012 and 2017 was conducted, allowing for a comparison between local diagnoses and the CPR diagnoses. Manual MYCN IHC was performed in the confirmed NB specimens and the results compared with known fluorescence in situ hybridization or automated IHC results, when available. RESULTS.­: The 156 specimens reviewed included 460 blocks and 183 original slides. Neuroblastoma was confirmed in 138 samples (88.5%), but low concordance rates for Shimada classification (n = 39; 25.0%), mitotic-karyorrhectic index (n = 4; 2.5%), and International Neuroblastoma Pathology Classification (n = 18; 11.5%) were noted. Manual MYCN IHC performed on 120 specimens showed conclusive results in 89.2% (28 positive, 23.4%; 79 negative, 65.8%) and questionable results in 10.8% (n = 13). CONCLUSIONS.­: This retrospective CPR highlights the need for a CPR program to serve this region, to ensure correct diagnosis and subclassification of NB, and to provide manual MYCN IHC-with reflexing to fluorescence in situ hybridization, if questionable. This approach can further regional collaboration, enhance test utilization, and ultimately improve patients' outcomes.


Assuntos
Neuroblastoma/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Lactente , Masculino , Neuroblastoma/classificação , Neuroblastoma/diagnóstico , Neuroblastoma/genética , Prognóstico , Encaminhamento e Consulta , Estudos Retrospectivos
12.
DNA Cell Biol ; 40(2): 332-347, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33393844

RESUMO

Neuroblastoma (NB) has the highest incidence of all extracranial solid tumors in children and is highly lethal. This study aims to establish a prognostic model of NB with MYCN-related genes. We determined the gene expression profiles of 900 NB samples from the UCSC database and four Gene Expression Omnibus (GEO) data sets, and performed a comprehensive bioinformatics analysis and clinical sample verification. After univariate Cox regression, least absolute shrinkage and selection operator (Lasso), and multivariate Cox regression analyses, four (AKR1C1, CHD5, PDE4DIP, and PRKACB) genes were finally selected and used to construct a risk score prognostic model. In the UCSC data set, the high-risk group exhibited a significantly worse prognosis than the low-risk group. In addition, the nomogram, which includes prognostic markers and clinical factors, demonstrates high prognostic value. Finally, the differential expression of the four genes in the model was verified by quantitative real-time PCR in clinical tissues. These findings of MYCN-related genes provide a new and reliable prognostic model for NB related to MYCN.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/diagnóstico , Neuroblastoma/genética , Reação em Cadeia da Polimerase em Tempo Real , 20-Hidroxiesteroide Desidrogenases/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/genética , Proteínas do Citoesqueleto/genética , DNA Helicases/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas do Tecido Nervoso/genética , Prognóstico
13.
Int J Mol Sci ; 22(2)2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33430186

RESUMO

The ability to establish, maintain, and reactivate from latency in sensory neurons within trigeminal ganglia (TG) is crucial for bovine herpesvirus 1 (BoHV-1) transmission. In contrast to lytic infection, the only viral gene abundantly expressed during latency is the latency-related (LR) gene. The synthetic corticosteroid dexamethasone consistently induces reactivation from latency, in part because the glucocorticoid receptor (GR) transactivates viral promoters that drive expression of key viral transcriptional regulator proteins (bICP0 and bICP4). Within hours after dexamethasone treatment of latently infected calves, LR gene products and ß-catenin are not readily detected in TG neurons. Hence, we hypothesized that LR gene products and/or ß-catenin restrict GR-mediated transcriptional activation. A plasmid expressing LR RNA sequences that span open reading frame 2 (ORF2-Stop) inhibited GR-mediated transactivation of the BoHV-1 immediate early transcription unit 1 (IEtu1) and mouse mammary tumor virus (MMTV) promoter activity in mouse neuroblastoma cells (Neuro-2A). ORF2-Stop also reduced productive infection and GR steady-state protein levels in transfected Neuro-2A cells. Additional studies revealed that the constitutively active ß-catenin mutant reduced the transactivation of the IEtu1 promoter by GR and dexamethasone. Collectively, these studies suggest ORF2 RNA sequences and Wnt/ß-catenin signaling pathway actively promote maintenance of latency, in part, by impairing GR-mediated gene expression.


Assuntos
Infecções por Herpesviridae/genética , RNA não Traduzido/genética , Proteínas Virais/genética , beta Catenina/genética , Animais , Bovinos , Dexametasona/farmacologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Infecções por Herpesviridae/virologia , Herpesvirus Bovino 1/genética , Herpesvirus Bovino 1/patogenicidade , Humanos , Vírus do Tumor Mamário do Camundongo/genética , Vírus do Tumor Mamário do Camundongo/patogenicidade , Camundongos , Neuroblastoma/genética , Neuroblastoma/virologia , Regiões Promotoras Genéticas/genética , RNA não Traduzido/farmacologia , Receptores de Glucocorticoides/genética , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/virologia , Fatores de Transcrição/genética , Gânglio Trigeminal/metabolismo , Gânglio Trigeminal/virologia , Latência Viral/genética , Via de Sinalização Wnt/efeitos dos fármacos
14.
Mol Oncol ; 15(2): 347-349, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33314654

RESUMO

In this issue, Coronado et al. attempt to improve our understanding of the factors affecting the response to immunotherapy in a large subset of high-risk neuroblastoma with hemizygous deletion of chromosome 11q. By using several computational approaches, the authors study potential transcriptional and post-transcriptional pathways that may affect the response to immunotherapy and further be leveraged therapeutically in a biomarker-directed fashion.


Assuntos
Neuroblastoma , Genômica , Humanos , Imunossupressão , Imunoterapia , Neuroblastoma/genética
15.
Ecotoxicol Environ Saf ; 209: 111832, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33383341

RESUMO

Cobalt has been known for its neurotoxicity in numerous studies. However, the molecular mechanism underlying cobalt-induced neurotoxicity remains largely unknown. In this study, two neuroblastoma (SHSY5Y and N2a) cell lines and a phaeochromocytoma (PC12) line were used as in vitro models. Cells were treated for 24 h with 50, 100, 200, 300, 400 µM cobalt chloride (CoCl2) or cultured with 300 µM CoCl2 for 4, 8, 12 and 24 h to investigate the effects of histone acetylation on CoCl2-induced neurodegenerative damages. Our findings demonstrate that CoCl2 suppresses the acetylation of histone H3 and H4 in a time-dependent and dosage-dependent manner. Furthermore, CoCl2 selectively decreases the expression and activity of histone acetyltransferase (HAT) but has no effects on histone deacetylase (HDAC) in SHSY5Y cells. More importantly, we show that 100 ng/mL HDAC inhibitor trichostatin (TSA) pre-treatment partly attenuates 300 µM CoCl2-induced neurodegenerative damages in SHSY5Y cells. Mechanistic analyses show that CoCl2-induced neurodegenerative damages are associated with the dysfunction of APP, BACE1, PSEN1, NEP and HIF-1α genes, whose expression are partly mediated by histone modification. In summary, we demonstrate that histone acetylation is involved in CoCl2-induced neurodegenerative damages. Our study indicates an important connection between histone modification and the pathological process of neurodegenerative damages and provides a mechanism for cobalt-mediated epigenetic regulation.


Assuntos
Cobalto/toxicidade , Histonas/fisiologia , Sistema Nervoso/efeitos dos fármacos , Acetilação/efeitos dos fármacos , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Linhagem Celular Tumoral , Cobalto/metabolismo , Epigênese Genética/efeitos dos fármacos , Inibidores de Histona Desacetilases/metabolismo , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Testes de Toxicidade
16.
PLoS One ; 15(12): e0244069, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33326488

RESUMO

In a previous study, we demonstrated that CHL1, the neuronal cell adhesion molecule close homolog of L1, acts as a tumor suppressor in human neuroblastoma (NB), a still highly lethal childhood malignancy, influencing its differentiation and proliferation degree. Here we found that ezrin, one of the ERM (ezrin, radixin, moesin) proteins involved in cytoskeleton organization, strongly interacts with CHL1. The low expression of EZRIN, as well as the low expression of CHL1 and of the neuronal differentiation marker MAP2, correlates with poor outcome in NB patients. Knock-down of ezrin in HTLA-230 cell line induces neurite retraction, enhances cell proliferation and migration, and triggers anchorage-independent growth, with effects very similar to those already obtained by CHL1 silencing. Furthermore, lack of ezrin inhibits the expression of MAP2 and of the oncosuppressor molecule p53, whereas it enhances MAPK activation, all typical features of tumor aggressiveness. As already described, CHL1 overexpression in IMR-32 cell line provokes an opposite trend, but the co-silencing of ezrin reduces these effects, confirming the hypothesis that CHL1 acts in close connection with ezrin. Overall, our data show that ezrin reinforces the differentiating and oncosuppressive functions of CHL1, identifying this ERM protein as a new targetable molecule for NB therapy.


Assuntos
Moléculas de Adesão Celular/metabolismo , Diferenciação Celular , Proteínas do Citoesqueleto/metabolismo , Sistema de Sinalização das MAP Quinases , Neuroblastoma/metabolismo , Neurônios/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Proteínas do Citoesqueleto/genética , Humanos , Neuroblastoma/genética , Neuroblastoma/patologia , Neurônios/patologia , Proteínas Supressoras de Tumor/genética
17.
Nat Commun ; 11(1): 5823, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33199677

RESUMO

MYCN amplification drives one in six cases of neuroblastoma. The supernumerary gene copies are commonly found on highly rearranged, extrachromosomal circular DNA (ecDNA). The exact amplicon structure has not been described thus far and the functional relevance of its rearrangements is unknown. Here, we analyze the MYCN amplicon structure using short-read and Nanopore sequencing and its chromatin landscape using ChIP-seq, ATAC-seq and Hi-C. This reveals two distinct classes of amplicons which explain the regulatory requirements for MYCN overexpression. The first class always co-amplifies a proximal enhancer driven by the noradrenergic core regulatory circuit (CRC). The second class of MYCN amplicons is characterized by high structural complexity, lacks key local enhancers, and instead contains distal chromosomal fragments harboring CRC-driven enhancers. Thus, ectopic enhancer hijacking can compensate for the loss of local gene regulatory elements and explains a large component of the structural diversity observed in MYCN amplification.


Assuntos
Cromossomos Humanos/genética , Elementos Facilitadores Genéticos/genética , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Acetilação , Sequência de Bases , Linhagem Celular Tumoral , Metilação de DNA/genética , DNA Circular/genética , Epigênese Genética , Histonas/metabolismo , Humanos , Estimativa de Kaplan-Meier , Lisina/metabolismo , Sequenciamento por Nanoporos
18.
Nat Commun ; 11(1): 5183, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33056981

RESUMO

Neuroblastoma is a pediatric malignancy with heterogeneous clinical outcomes. To better understand neuroblastoma pathogenesis, here we analyze whole-genome, whole-exome and/or transcriptome data from 702 neuroblastoma samples. Forty percent of samples harbor at least one recurrent driver gene alteration and most aberrations, including MYCN, ATRX, and TERT alterations, differ in frequency by age. MYCN alterations occur at median 2.3 years of age, TERT at 3.8 years, and ATRX at 5.6 years. COSMIC mutational signature 18, previously associated with reactive oxygen species, is the most common cause of driver point mutations in neuroblastoma, including most ALK and Ras-activating variants. Signature 18 appears early and is continuous throughout disease evolution. Signature 18 is enriched in neuroblastomas with MYCN amplification, 17q gain, and increased expression of mitochondrial ribosome and electron transport-associated genes. Recurrent FGFR1 variants in six patients, and ALK N-terminal structural alterations in five samples, identify additional patients potentially amenable to precision therapy.


Assuntos
Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Neuroblastoma/genética , Adolescente , Adulto , Fatores Etários , Quinase do Linfoma Anaplásico/genética , Criança , Pré-Escolar , Estudos de Coortes , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Conjuntos de Dados como Assunto , Transporte de Elétrons/genética , Exoma/genética , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Ribossomos Mitocondriais , Mutação , Neuroblastoma/patologia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Proteínas Ribossômicas/genética , Transcriptoma/genética , Sequenciamento Completo do Genoma , Adulto Jovem
19.
Anticancer Res ; 40(9): 5151-5158, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878803

RESUMO

BACKGROUND/AIM: Magnetic stimulation is used in the treatment of a diversity of diseases, but a complete understanding of the underlying mechanisms of action requires further investigation. We examined the effect of static magnetic stimulation (SMS) in different cell lines. MATERIALS AND METHODS: A culture plate holder with attached NeFeB magnets was developed. Different magnetic field intensities and periods were tested in tumoral and non-tumoral cell lines. To verify the cellular responses to SMS, cell viability, cell death, cell cycle and BDNF expression were evaluated. RESULTS: Exposure of SH-SY5Y cells to SMS for 24 hours led to a decrease in cell viability. Analysis 24 h after stimulation revealed a decrease in apoptotic and double-positive cells, associated with an increase in the number of necrotic cells. CONCLUSION: The effects of SMS on cell viability are cell type-specific, inducing a decrease in cell viability in SH-SY5Y cells. This suggests that SMS may be a potential tool in the treatment of neuronal tumors.


Assuntos
Sobrevivência Celular/efeitos da radiação , Fenômenos Magnéticos , Apoptose/efeitos da radiação , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Neuroblastoma/genética , Neuroblastoma/metabolismo , Especificidade de Órgãos/efeitos da radiação
20.
Proc Natl Acad Sci U S A ; 117(28): 16516-16526, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601179

RESUMO

LIN28B is highly expressed in neuroblastoma and promotes tumorigenesis, at least, in part, through inhibition of let-7 microRNA biogenesis. Here, we report that overexpression of either wild-type (WT) LIN28B or a LIN28B mutant that is unable to inhibit let-7 processing increases the penetrance of MYCN-induced neuroblastoma, potentiates the invasion and migration of transformed sympathetic neuroblasts, and drives distant metastases in vivo. Genome-wide chromatin immunoprecipitation coupled with massively parallel DNA sequencing (ChIP-seq) and coimmunoprecipitation experiments show that LIN28B binds active gene promoters in neuroblastoma cells through protein-protein interaction with the sequence-specific zinc-finger transcription factor ZNF143 and activates the expression of downstream targets, including transcription factors forming the adrenergic core regulatory circuitry that controls the malignant cell state in neuroblastoma as well as GSK3B and L1CAM that are involved in neuronal cell adhesion and migration. These findings reveal an unexpected let-7-independent function of LIN28B in transcriptional regulation during neuroblastoma pathogenesis.


Assuntos
Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transativadores/metabolismo , Animais , Animais Geneticamente Modificados , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Neuroblastoma/fisiopatologia , Ligação Proteica , Proteínas de Ligação a RNA/genética , Transativadores/genética , Peixe-Zebra
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