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1.
Ann Clin Transl Neurol ; 11(8): 2153-2165, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38925618

RESUMO

OBJECTIVES: Neuroblastoma is the most common extracranial solid tumor in childhood. YAP (Yes-associated protein) is a highly expressed protein in NB. Nestin is an important marker of neuronal differentiation in NB. Orthodenticle homeobox (OTX) is a transcription factor and is overexpressed in blastoma-derived tumors. The aim of this study was to examine the potential roles of YAP-1, Nestin, and OTX-2 proteins in prognosis and risk stratification in neuroblastoma METHODS: Tumor sections of 56 patients with different NB risk groups were analyzed. YAP-1, Nestin, and OTX-2 protein expression levels were evaluated by immunohistochemical staining in NB patient tissue samples. RESULTS: YAP-1, Nestin, and OTX-2 protein expression levels were evaluated together with the clinical findings of NB patients. YAP-1 was expressed in 18% of all tissues, while Nestin was expressed in 20.4%. OTX-2 protein expression was found in 41.1% of the NB patients. YAP-1 was expressed in 26.9% of high-risk and 11.5% of low-risk patients. Nestin was expressed in 24.4% high-risk and 33.3% low-risk patients. OTX-2 was expressed in 68.2% high-risk and 60% low-risk patients.YAP-1 was shown to provide survival advantages among risk groups. INTERPRETATION: The findings of this study support that YAP-1 may be a potential prognostic biomarker for staging and risk-group assignment of NB patients. YAP-1 expression in neuroblastoma is associated with significantly poorer survival probabilities and should be considered as a potential therapeutic target. OTX-2 is a promising predictive biomarker candidate, but its mechanisms need further investigation in neuroblastoma, as nestin expression is not significantly linked to patient survival.


Assuntos
Nestina , Neuroblastoma , Fatores de Transcrição Otx , Fatores de Transcrição , Proteínas de Sinalização YAP , Humanos , Nestina/metabolismo , Neuroblastoma/metabolismo , Feminino , Masculino , Proteínas de Sinalização YAP/metabolismo , Pré-Escolar , Fatores de Transcrição Otx/metabolismo , Lactente , Fatores de Transcrição/metabolismo , Criança , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais/metabolismo , Prognóstico
3.
J Pediatr Hematol Oncol ; 46(1): 21-28, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37943051

RESUMO

Neuroblastoma (NB) is the most frequent extracranial solid tumor of childhood, remarkable for its broad spectrum of clinical behavior. This diversity in behavior correlates closely with defined clinical and biological features and combinations of prognostic variables are used for risk-group assignment. S-100 proteins have roles in differentiation and were shown to be frequently dysregulated in NB. MATH-1 protein plays role in neuronal cell differentiation through development. However, up to date, there are no studies evaluating the relationship between MATH-1 and NB. Grb2-associated binding (Gab) proteins have roles in the regulation of cell growth and differentiation. Gab1 was reported to be related to poor survival of high-risk NB patients. The aim of this study was to investigate the relationship between differentiation-related S-100, MATH-1, and Gab1 proteins and risk group and/or stages of NB. A significant relation was found between S-100 and early stages of NB. This study also revealed a significant association between MATH-1 and low-risk groups. S-100 and MATH-1 were also shown to provide survival advantages among stages and risk groups. The findings of this study support the assumption that S-100 and MATH-1 can be potential prognostic biomarkers for staging and risk-group assignment of NB patients. These proteins can be useful tools for clinicians to guide through treatment options, especially for the evaluation of tumor differentiation.


Assuntos
Neuroblastoma , Humanos , Diferenciação Celular , Linhagem Celular Tumoral , Neuroblastoma/patologia , Prognóstico , Fatores de Risco
4.
Clin Med Insights Oncol ; 17: 11795549231199926, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744426

RESUMO

Background: Tribbles Homolog 3 (TRIB3) is a member of the pseudokinase family of tribbles and acts as an adaptor protein to regulate different cellular processes. Upregulation of TRIB3 expression was shown either as a favorable or an adverse prognostic factor in various adult malignancies. However, TRIB3 expression has not been examined in pediatric cancers. Neuroblastoma is the most common malignant solid tumor of childhood, which affects mostly children under 5 years old. Risk stratification of patients defined by International Neuroblastoma Risk Group was used to determine prognosis and treatment of the disease. This study aimed to examine the relationship between TRIB3 protein expression levels and clinicopathological features and survival of patients. Methods: TRIB3 protein expression was analyzed using immunohistochemical staining on formalin-fixed paraffin-embedded tissue samples of neuroblastoma patients (n = 56). Survival analyses were performed with Kaplan-Meier method and log-rank tests. Association between TRIB3 expression and clinicopathological characteristics were analyzed with Spearman's correlation. Results: Of the patients, 32.1% were in the low-risk group, 21.4% in the medium-risk group, and 46.4% in the high-risk group. Survival analysis was performed in the entire neuroblastoma patient group and sub-risk groups of neuroblastoma patients. In the entire patient group, there was no significant difference in overall survival (P = .202) and event-free survival (P = .172) between TRIB3-positive and -negative patients. However, when survival analyses were performed in each risk group, TRIB3 expression was significantly associated with higher overall survival (P = .034) and event-free survival (P = .032) in low-risk group neuroblastoma patients. Nevertheless, no association was found between TRIB3 expression and overall survival (P = .799) and event-free survival (P = .448) in high-risk neuroblastoma patients. Furthermore, a significant correlation was identified between 1p36 loss-of-heterozygosity and TRIB3 expression (P = .030). However, TRIB3 expression did not correlate with other clinicopathological features. Conclusion: TRIB3 expression is a potential predictive biomarker for low-risk neuroblastoma patients.

5.
Proc Natl Acad Sci U S A ; 120(16): e2214997120, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37043537

RESUMO

While somatic variants of TRAF7 (Tumor necrosis factor receptor-associated factor 7) underlie anterior skull-base meningiomas, here we report the inherited mutations of TRAF7 that cause congenital heart defects. We show that TRAF7 mutants operate in a dominant manner, inhibiting protein function via heterodimerization with wild-type protein. Further, the shared genetics of the two disparate pathologies can be traced to the common origin of forebrain meninges and cardiac outflow tract from the TRAF7-expressing neural crest. Somatic and inherited mutations disrupt TRAF7-IFT57 interactions leading to cilia degradation. TRAF7-mutant meningioma primary cultures lack cilia, and TRAF7 knockdown causes cardiac, craniofacial, and ciliary defects in Xenopus and zebrafish, suggesting a mechanistic convergence for TRAF7-driven meningiomas and developmental heart defects.


Assuntos
Cardiopatias Congênitas , Neoplasias Meníngeas , Meningioma , Animais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Cardiopatias Congênitas/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Meningioma/patologia , Mutação , Crânio/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Humanos , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral
6.
Gene ; 860: 147233, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36736507

RESUMO

This study aimed to investigate the genetic aberrations in neuroblastoma (NB) by comparing high and low-risk NB patients by whole-exome sequencing (WES) and to reveal the heterogeneity and association between somatic variants and clinical features. Seven NB patients with available clinical data were included in the study (4 in the low-risk group and 3 in the high-risk group). WES was performed and somatic variants associated with NB genes in the COSMIC database were selected through bioinformatics pipeline analysis. Variants were determined using the Integrative Genomics Viewer (IGV). Some gene variations were found in both groups, including variations in oncogene and tumor suppressor genes. In general, candidate gene variations were associated with chromatin remodeling complexes, the RAS pathway, cell proliferation, and DNA repair mechanism. Some variations in CSF1R, MSH6, PTPN11, SOX9, RET, TSC1, and DNMT1 genes were detected only in high-risk patients, while EP300, TET2, MYCN, PRDM1, and ARID2 gene variations were detected only in low-risk patients. When high-risk gene variants were compared with the cBioportal cancer genomic database, two common gene variants (ARID1A and NCOR2) were identified. However, when low-risk gene variants were compared with the cBioportal cancer genomic database, no common genes were found. GO/KEGG enrichment analysis was performed to find relevant biological processes and molecular pathways related to gene variants, which will help to decipher the molecular mechanisms of NB tumorigenesis and the phenotypic differences between high-risk and low-risk patients.


Assuntos
Neuroblastoma , Oncogenes , Humanos , Sequenciamento do Exoma , Genômica , Fatores de Risco , Neuroblastoma/genética , Neuroblastoma/patologia
7.
Int J Clin Exp Pathol ; 12(8): 3140-3148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31934157

RESUMO

OBJECTIVE: Despite conventional histopathological and immunohistochemical methods, difficulties may be experienced in the differential diagnosis of pediatric cancers, especially in small round-cell undifferentiated tumors. In these cases, the determination of chromosomal abnormalities may be helpful. The aim of this study was to evaluate the place of the whole genome array comparative genomic hybridization method in pediatric cancers where difficulty is experienced in differential diagnosis. METHOD: In Comparative Genomic Hybridization (CGH), 135,000 probes were scanned as 3 probes per gene in all genomes. It was possible to analyze paraffin block tissues obtained from the archive of the Pathology Laboratory of Dr. Behcet Uz Children's Hospital. DNA extraction was made from the paraffin blocks of 24 cases where difficulty had been experienced in making the differential diagnosis and in each case, comparisons with the control samples were made for all anomalies in all chromosomes using microarray technology. RESULTS: Together with the typically observed chromosomal anomalies, additional derangements with debatable importance were determined. CONCLUSION: The whole genome CGH method may be useful in pediatric cancers where difficulties are experienced in making differential diagnoses. Since technical difficulties are experienced in the examination of paraffin-embedded tissue samples, storing fresh tissue samples from each tumor will be helpful for genetic and molecular examinations.

8.
Gastroenterology Res ; 11(4): 264-273, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30116425

RESUMO

Colorectal cancer is the third most common cancer worldwide with a high mortality rate at the advanced stages. However, colorectal cancer is not a single type of tumor; its pathogenesis depends on the anatomical location of the tumor and differs between right side and left side of the colon. Tumors in the proximal colon (right side) and distal colon (left side) exhibit different molecular characteristics and histology. In the right-sided tumors, mutations in the DNA mismatch repair pathway are commonly observed; and these tumors generally have a flat histology. In the left-sided tumors, chromosomal instability pathway-related mutations, such as KRAS, APC, PIK3CA, p53 mutations are observed and these tumors demonstrate polypoid-like morphology. Therapy responses are totally different between these tumor entities. Left-sided colorectal cancer (LCRC) patients benefit more from adjuvant chemotherapies such as 5-fluorouracil (5-FU)-based regimes, and targeted therapies such as anti- epidermal growth factor receptor (EGFR) therapy, and have a better prognosis. Right-sided colorectal cancer (RCRC) patients do not respond well to conventional chemotherapies, but demonstrate more promising results with immunotherapies because these tumors have high antigenic load. For the development of effective therapy regimes and better treatment options, it is essential to evaluate right-sided and left-sided tumors as separate entities, and design the therapy regime considering the differences between these tumors.

10.
Nat Commun ; 8: 14433, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28195122

RESUMO

Meningiomas are mostly benign brain tumours, with a potential for becoming atypical or malignant. On the basis of comprehensive genomic, transcriptomic and epigenomic analyses, we compared benign meningiomas to atypical ones. Here, we show that the majority of primary (de novo) atypical meningiomas display loss of NF2, which co-occurs either with genomic instability or recurrent SMARCB1 mutations. These tumours harbour increased H3K27me3 signal and a hypermethylated phenotype, mainly occupying the polycomb repressive complex 2 (PRC2) binding sites in human embryonic stem cells, thereby phenocopying a more primitive cellular state. Consistent with this observation, atypical meningiomas exhibit upregulation of EZH2, the catalytic subunit of the PRC2 complex, as well as the E2F2 and FOXM1 transcriptional networks. Importantly, these primary atypical meningiomas do not harbour TERT promoter mutations, which have been reported in atypical tumours that progressed from benign ones. Our results establish the genomic landscape of primary atypical meningiomas and potential therapeutic targets.


Assuntos
Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/fisiologia , Genoma , Genômica/métodos , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/metabolismo , Meningioma/genética , Meningioma/metabolismo , Sítios de Ligação , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Transformação Celular Neoplásica/genética , Instabilidade Cromossômica , Análise por Conglomerados , Metilação de DNA , Fator de Transcrição E2F2/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigenômica/métodos , Exoma/genética , Proteína Forkhead Box M1/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Genes da Neurofibromatose 2 , Técnicas de Genotipagem , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Técnicas de Sonda Molecular , Mutação , Fenótipo , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Proteína SMARCB1/genética , Análise de Sequência , Transdução de Sinais/genética , Transcriptoma
11.
J Hum Genet ; 61(5): 395-403, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26740239

RESUMO

The fat mass and obesity associated (FTO) gene has previously been associated with a variety of diseases and conditions, notably obesity, acute coronary syndrome and metabolic syndrome. Reports describing mutations in FTO as well as in FTO animal models have further demonstrated a role for FTO in the development of the brain and other organs. Here, we describe a patient born of consanguineous union who presented with microcephaly, developmental delay, behavioral abnormalities, dysmorphic facial features, hypotonia and other various phenotypic abnormalities. Whole-exome sequencing revealed a novel homozygous missense mutation in FTO and a nonsense mutation in the cholesteryl ester transfer protein (CETP). Exome copy number variation analysis revealed no disease-causing large duplications or deletions within coding regions. Patient's, her parents' and non-related control' fibroblasts were analyzed for morphologic defects, abnormal proliferation, apoptosis and transcriptome profile. We have shown that FTO is located in the nucleus of cells from each tested sample. Western blot analysis demonstrated no changes in patient FTO. Quantitative (qPCR) analysis revealed slightly decreased levels of FTO expression in patient cells compared with controls. No morphological or proliferation differences between the patient and control fibroblasts were observed. There is still much to be learned about the molecular mechanisms by which mutations in FTO contribute to such severe phenotypes.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Proteínas de Transferência de Ésteres de Colesterol/genética , Estudos de Associação Genética , Homozigoto , Mutação de Sentido Incorreto , Apoptose/genética , Biópsia , Pré-Escolar , Biologia Computacional/métodos , Consanguinidade , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Exoma , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Fenótipo , Transcriptoma
12.
Neuropediatrics ; 46(6): 420-3, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26479764

RESUMO

Tangier disease (TD) is a rare, autosomal recessive inherited disorder caused by a mutation in the adenosine triphosphate-binding cassette transporter 1 (ABCA1) gene, which results in a decrease in plasma high-density lipoprotein (HDL) levels. Peripheral neuropathy can be seen in approximately 50% of patients with TD, which usually occurs after the age of 15 years, and is characterized by relapsing-remitting mono- or polyneuropathy or syringomyelia-like neuropathy. Herein, we report a 16-year-old female patient who was initially diagnosed with peripheral neuropathy at the age of 13 years. Whole exome sequencing was performed, and a nonsense mutation (p.Arg1817X) in ABCA1 was identified. The patient was investigated for systemic findings of TD after the genetic diagnosis was made, and low (< 5 mg/dL) levels of HDL cholesterol were detected by lipid electrophoresis. Other family members were reexamined after the diagnosis of the proband, and asymptomatic sister of the proband was diagnosed with TD. We would like to emphasize that TD should be considered in the differential diagnosis of pediatric patients presenting with peripheral neuropathy; furthermore detection of HDL levels by lipid electrophoresis is a simple but indicative diagnostic test.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/genética , Códon sem Sentido , Doenças do Sistema Nervoso Periférico/etiologia , Doença de Tangier/diagnóstico , Adolescente , HDL-Colesterol/sangue , Exoma , Feminino , Humanos , Linhagem , Análise de Sequência de DNA , Siringomielia/genética , Doença de Tangier/genética , Doença de Tangier/fisiopatologia
13.
Neuro Oncol ; 17(10): 1356-64, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25740784

RESUMO

BACKGROUND: Malignant high-grade gliomas (HGGs), including the most aggressive form, glioblastoma multiforme, show significant clinical and genomic heterogeneity. Despite recent advances, the overall survival of HGGs and their response to treatment remain poor. In order to gain further insight into disease pathophysiology by correlating genomic landscape with clinical behavior, thereby identifying distinct HGG molecular subgroups associated with improved prognosis, we performed a comprehensive genomic analysis. METHODS: We analyzed and compared 720 exome-sequenced gliomas (136 from Yale, 584 from The Cancer Genome Atlas) based on their genomic, histological, and clinical features. RESULTS: We identified a subgroup of HGGs (6 total, 4 adults and 2 children) that harbored a statistically significantly increased number of somatic mutations (mean = 9257.3 vs 76.2, P = .002). All of these "ultramutated" tumors harbored somatic mutations in the exonuclease domain of the polymerase epsilon gene (POLE), displaying a distinctive genetic profile, characterized by genomic stability and increased C-to-A transversions. Histologically, they all harbored multinucleated giant or bizarre cells, some with predominant infiltrating immune cells. One adult and both pediatric patients carried homozygous germline mutations in the mutS homolog 6 (MSH6) gene. In adults, POLE mutations were observed in patients younger than 40 years and were associated with a longer progression-free survival. CONCLUSIONS: We identified a genomically, histologically, and clinically distinct subgroup of HGGs that harbored somatic POLE mutations and carried an improved prognosis. Identification of distinctive molecular and pathological HGG phenotypes has implications not only for improved classification but also for potential targeted treatments.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , DNA Polimerase II/genética , Glioma/genética , Glioma/patologia , Mutação , Adulto , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/diagnóstico , Criança , Pré-Escolar , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Intervalo Livre de Doença , Glioma/classificação , Glioma/diagnóstico , Humanos , Fenótipo , Proteínas de Ligação a Poli-ADP-Ribose , Prognóstico , Adulto Jovem
14.
Neuron ; 84(6): 1226-39, 2014 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-25521378

RESUMO

Exome sequencing analysis of over 2,000 children with complex malformations of cortical development identified five independent (four homozygous and one compound heterozygous) deleterious mutations in KATNB1, encoding the regulatory subunit of the microtubule-severing enzyme Katanin. Mitotic spindle formation is defective in patient-derived fibroblasts, a consequence of disrupted interactions of mutant KATNB1 with KATNA1, the catalytic subunit of Katanin, and other microtubule-associated proteins. Loss of KATNB1 orthologs in zebrafish (katnb1) and flies (kat80) results in microcephaly, recapitulating the human phenotype. In the developing Drosophila optic lobe, kat80 loss specifically affects the asymmetrically dividing neuroblasts, which display supernumerary centrosomes and spindle abnormalities during mitosis, leading to cell cycle progression delays and reduced cell numbers. Furthermore, kat80 depletion results in dendritic arborization defects in sensory and motor neurons, affecting neural architecture. Taken together, we provide insight into the mechanisms by which KATNB1 mutations cause human cerebral cortical malformations, demonstrating its fundamental role during brain development.


Assuntos
Adenosina Trifosfatases/genética , Encéfalo/anormalidades , Encéfalo/patologia , Microcefalia/genética , Células-Tronco Neurais/patologia , Neurogênese/genética , Lobo Óptico de Animais não Mamíferos/anormalidades , Animais , Encéfalo/crescimento & desenvolvimento , Contagem de Células , Divisão Celular/genética , Dendritos/genética , Drosophila , Proteínas de Drosophila/genética , Humanos , Katanina , Camundongos , Microcefalia/patologia , Proteínas Associadas aos Microtúbulos/genética , Mutação , Fuso Acromático/genética , Peixe-Zebra
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