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1.
J Neurooncol ; 167(1): 145-154, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38457090

RESUMO

PURPOSE: Adult Diffuse midline glioma (DMG) is a very rare disease. DMGs are currently treated with radiotherapy and chemotherapy even if only a few retrospective studies assessed the impact on overall survival (OS) of these approaches. METHODS: We carried out an Italian multicentric retrospective study of adult patients with H3K27-altered DMG to assess the effective role of systemic therapy in the treatment landscape of this rare tumor type. RESULTS: We evaluated 49 patients from 6 Institutions. The median age was 37.3 years (range 20.1-68.3). Most patients received biopsy as primary approach (n = 30, 61.2%) and radiation therapy after surgery (n = 39, 79.6%). 25 (51.0%) of patients received concurrent chemotherapy and 26 (53.1%) patients received adjuvant temozolomide. In univariate analysis, concurrent chemotherapy did not result in OS improvement while adjuvant temozolomide was associated with longer OS (21.2 vs. 9.0 months, HR 0.14, 0.05-0.41, p < 0.001). Multivariate analysis confirmed the role of adjuvant chemotherapy (HR 0.1, 95%CI: 0.03-0.34, p = 0.003). In patients who progressed after radiation and/or chemotherapy the administration of a second-line systemic treatment had a significantly favorable impact on survival (8.0 vs. 3.2 months, HR 0.2, 95%CI 0.1-0.65, p = 0.004). CONCLUSION: In our series, adjuvant treatment after radiotherapy can be useful in improving OS of patients with H3K27-altered DMG. When feasible another systemic treatment after treatment progression could be proposed.


Assuntos
Neoplasias Encefálicas , Glioma , Adulto , Humanos , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Temozolomida/uso terapêutico , Estudos Retrospectivos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Antineoplásicos Alquilantes/uso terapêutico , Glioma/tratamento farmacológico , Glioma/patologia , Dacarbazina/uso terapêutico , Quimioterapia Adjuvante
2.
Childs Nerv Syst ; 40(4): 1053-1064, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38376530

RESUMO

PURPOSE: Brain stem tumors in children < 3 months at diagnosis are extremely rare. Our aim is to study a retrospective cohort to improve the understanding of the disease course and guide patient management. METHODS: This is a multicenter retrospective analysis across the European Society for Pediatric Oncology SIOP-E HGG/DIPG Working Group linked centers, including patients with a brainstem tumor diagnosed between 2009 and 2020 and aged < 3 months at diagnosis. Clinical data were collected, and imaging characteristics were analyzed blindly and independently by two neuroradiologists. RESULTS: Five cases were identified. No patient received any therapy. The epicenter of two tumors was in the medulla oblongata alone and in the medulla oblongata and the pons in three. For patients with tumor in equal parts in the medulla oblongata and the pons (n = 3), the extension at diagnosis involved the spinal cord; for the two patients with the tumor epicenter in the medulla oblongata alone (n = 2), the extension at diagnosis included the pons (n = 2) and the spinal cord (n = 1). Biopsy was performed in one patient identifying a pilocytic astrocytoma. Two patients died. In one patient, autopsy revealed a high-grade glioma (case 3). Three survivors showed either spontaneous tumor regression (n = 2) or stable disease (n = 1). Survivors were followed up for 10, 7, and 0.6 years, respectively. One case had the typical imaging characteristics of a dorsal exophytic low-grade glioma. CONCLUSIONS: No patient fulfilled the radiologic criteria defining a high-grade glioma. Central neuroradiological review and biopsy may provide useful information regarding the patient management.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Neoplasias do Tronco Encefálico , Glioma , Criança , Humanos , Estudos Retrospectivos , Doenças Raras , Neoplasias do Tronco Encefálico/terapia , Glioma/patologia , Astrocitoma/patologia , Neoplasias Encefálicas/patologia
3.
Childs Nerv Syst ; 40(1): 65-71, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37644138

RESUMO

PURPOSE: Diffuse Midline Glioma (DMG) with H3K27M mutation is a rare and aggressive midline high grade glioma with a predominant astrocytic differentiation and K27M mutation in either H3F3A or HIST1H3B/C. This tumor is more common in children than in adults. The current study was aimed to determine clinicohistoradiological and surgical outcome of patients who have undergone surgery for DMG and study disease severity of patients with DMG. METHODS: This is an observational study in which 29 DMG patients were evaluated for clinicohistoradiological and surgical outcomes by assessing the pre and postoperative neurological status. RESULT: Survival duration was significantly high in patients with age > 18 years (p = 0.02). Patients who had undergone Radiation Therapy showed higher survival rate (p = 0.05) and the cases with low levels of Ki 67 index had improved post operative outcome (p = 0.002). CONCLUSION: DMG with H3K27M mutation in newly classified Central Nervous System tumor are WHO grade IV Tumors, comprising H3K27M mutation as molecular marker for diagnosis and related with a poor prognosis.


Assuntos
Neoplasias Encefálicas , Glioma , Criança , Adulto , Humanos , Pessoa de Meia-Idade , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Histonas/genética , Glioma/genética , Glioma/cirurgia , Glioma/diagnóstico , Mutação/genética , Resultado do Tratamento
4.
Int J Mol Sci ; 25(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38542334

RESUMO

The BMP pathway is one of the major signaling pathways in embryonic development, ontogeny and homeostasis, identified many years ago by pioneers in developmental biology. Evidence of the deregulation of its activity has also emerged in many cancers, with complex and sometimes opposing effects. Recently, its role has been suspected in Diffuse Midline Gliomas (DMG), among which Diffuse Intrinsic Pontine Gliomas (DIPG) are one of the most complex challenges in pediatric oncology. Genomic sequencing has led to understanding part of their molecular etiology, with the identification of histone H3 mutations in a large proportion of patients. The epigenetic remodeling associated with these genetic alterations has also been precisely described, creating a permissive context for oncogenic transcriptional program activation. This review aims to describe the new findings about the involvement of BMP pathway activation in these tumors, placing their appearance in a developmental context. Targeting the oncogenic synergy resulting from this pathway activation in an H3K27M context could offer new therapeutic perspectives based on targeting treatment-resistant cell states.


Assuntos
Glioma Pontino Intrínseco Difuso , Glioma , Humanos , Criança , Glioma/metabolismo , Histonas/metabolismo , Glioma Pontino Intrínseco Difuso/genética , Glioma Pontino Intrínseco Difuso/metabolismo , Glioma Pontino Intrínseco Difuso/patologia , Mutação , Transdução de Sinais , Proteínas Morfogenéticas Ósseas/metabolismo
5.
Int J Mol Sci ; 24(14)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37511024

RESUMO

N,N-dimethylglycine (DMG) is a naturally occurring compound being widely used as an oral supplement to improve growth and physical performance. Thus far, its effects on human skin have not been described in the literature. For the first time, we show that N,N-dimethylglycine sodium salt (DMG-Na) promoted the proliferation of cultured human epidermal HaCaT keratinocytes. Even at high doses, DMG-Na did not compromise the cellular viability of these cells. In a scratch wound-closure assay, DMG-Na augmented the rate of wound closure, demonstrating that it promotes keratinocyte migration. Further, DMG-Na treatment of the cells resulted in the upregulation of the synthesis and release of specific growth factors. Intriguingly, DMG-Na also exerted robust anti-inflammatory and antioxidant effects, as assessed in three different models of human keratinocytes, mimicking microbial and allergic contact dermatitis as well as psoriasis and UVB irradiation-induced solar dermatitis. These results identify DMG-Na as a highly promising novel active compound to promote epidermal proliferation, regeneration, and repair, and to exert protective functions. Further preclinical and clinical studies are under investigation to prove the seminal impact of topically applied DMG-Na on relevant conditions of the skin and its appendages.


Assuntos
Dermatite , Queratinócitos , Humanos , Proliferação de Células , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia
6.
J Cell Biochem ; 123(3): 628-643, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34989009

RESUMO

In this study, multicomplex-based pharmacophore modeling was conducted on the structural proteome of the two states of CDK8 protein, that is, DMG-in and out. Three pharmacophores having six, five, and four features were selected as the representative models to conduct the virtual screening process using the prepared drug-like natural product database. The screened candidates were subjected to molecular docking studies on DMG-in (5XS2) and out (4F6U) conformation of the CDK8 protein. Subsequently, the common four docked candidates of 5XS2 and 4F6U were selected to perform the molecular dynamics simulation studies. Apart from one of the complexes of DMG-in (5XS2-UNPD163102), all other complexes displayed stable dynamic behavior. The interaction and stability studies of the docked complexes were compared with the references selected from the two conformations (DMG-in and out) of the protein. The current work leads to the identification of three common DMG-in and out hits with diverse scaffolds which can be employed as the initial leads for the design of the novel CDK8 inhibitors.


Assuntos
Inibidores Enzimáticos , Simulação de Dinâmica Molecular , Inibidores Enzimáticos/farmacologia , Ligantes , Simulação de Acoplamento Molecular
7.
Acta Neuropathol ; 143(1): 1-13, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34762160

RESUMO

Ependymomas (EPN) are tumors of the central nervous system (CNS) that can arise in the supratentorial brain (ST-EPN), hindbrain or posterior fossa (PF-EPN) or anywhere in the spinal cord (SP-EPN), both in children and adults. Molecular profiling studies have identified distinct groups and subtypes in each of these anatomical compartments. In this review, we give an overview on recent findings and new insights what is driving PFA ependymomas, which is the most common group. PFA ependymomas are characterized by a young median age at diagnosis, an overall balanced genome and a bad clinical outcome (56% 10-year overall survival). Sequencing studies revealed no fusion genes or other highly recurrently mutated genes, suggesting that the disease is epigenetically driven. Indeed, recent findings have shown that the characteristic global loss of the repressive histone 3 lysine 27 trimethylation (H3K27me3) mark in PFA ependymoma is caused by aberrant expression of the enhancer of zeste homolog inhibitory protein (EZHIP) or in rare cases by H3K27M mutations, which both inhibit EZH2 thereby preventing the polycomb repressive complex 2 (PRC2) from spreading H3K27me3. We present the current status of the ongoing work on EZHIP and its essential role in the epigenetic disturbance of PFA biology. Comparisons to the oncohistone H3K27M and its role in diffuse midline glioma (DMG) are drawn, highlighting similarities but also differences between the tumor entities and underlying mechanisms. A strong focus is to point out missing information and to present directions of further research that may result in new and improved therapies for PFA ependymoma patients.


Assuntos
Ependimoma/genética , Neoplasias Infratentoriais/genética , Proteínas Oncogênicas/genética , Criança , Feminino , Humanos , Masculino
8.
Trends Immunol ; 40(8): 748-761, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31229353

RESUMO

Pediatric brain tumors are the leading cause of childhood cancer-related death. Immunotherapy is a powerful new approach for treating some refractory cancers; applying this 'fourth pillar' of cancer treatment to pediatric brain tumors is an exciting but challenging prospect. This review offers new perspectives on moving towards successful immunotherapy for pediatric brain tumors, focusing on pediatric high-grade glioma (HGG), a subgroup with universally poor outcomes. We cover chimeric antigen receptor T cell (CAR-T) therapy, vaccine therapy, and checkpoint inhibition in this context, and focus on the need for intimately understanding the growing brain and its immune system. We highlight the challenges associated with the application of immunotherapy in pediatric neuro-oncology, as well as the tissue-specific challenges to be overcome, to achieve improved outcomes.


Assuntos
Neoplasias Encefálicas/terapia , Imunoterapia , Fatores Etários , Animais , Antineoplásicos Imunológicos , Biomarcadores Tumorais , Neoplasias Encefálicas/etiologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Criança , Gerenciamento Clínico , Suscetibilidade a Doenças , Humanos , Imunoterapia/métodos , Imunoterapia Adotiva/métodos , Terapia de Alvo Molecular , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-34983324

RESUMO

Contact allergy to Nickel is the most prevalent contact allergy in western societies. This has led to regulation for metallic items that come into prolonged and direct contact with the skin, such as buttons on clothing, belt buckles, jewelry and watches. In Europe, the legal provision is based on a test in which there is a limit to the amount of nickel that may be released from the item to an artificial sweat solution (EN 1811). This test is costly and has reproducibility issues. The resulting undertesting of items placed on the market, leads to many nickel releasing non-compliant articles being available in spite of the regulations that are in place. In this study, the performance of the standard release test is compared to the performance of a rapid nickel spot test based on dimethylglyoxime (DMG-test). The data suggest that using the rapid DMG-test for compliance testing is sufficiently equivalent to the current gold standard of EN 1811. Previously published comparisons between the DMG-test and EN 1811 did not consider the effect of accelerated wear and corrosion testing according to EN 12472. This study shows that by applying EN 12472, the number of deviating results between the DMG-test and EN 1811 decreases significantly. Regarding consumer protection, it is necessary for wear and corrosion resistance to be considered.


Assuntos
Dermatite Alérgica de Contato , Joias , Dermatite Alérgica de Contato/etiologia , Dermatite Alérgica de Contato/prevenção & controle , Europa (Continente) , Humanos , Níquel/análise , Reprodutibilidade dos Testes
10.
Pathologica ; 114(6): 422-435, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36534421

RESUMO

As a relevant element of novelty, the fifth CNS WHO Classification highlights the distinctive pathobiology underlying gliomas arising primarily in children by recognizing for the first time the families of paediatric-type diffuse gliomas, both high-grade and low-grade. This review will focus on the family of paediatric-type diffuse high-grade gliomas, which includes four tumour types: 1) Diffuse midline glioma H3 K27-altered; 2) Diffuse hemispheric glioma H3 G34-mutant; 3) Diffuse paediatric-type high-grade glioma H3-wildtype and IDH-wildtype; and 4) Infant-type hemispheric glioma. The essential and desirable diagnostic criteria as well as the entities entering in the differential will be discussed for each tumour type. A special focus will be given on the issues encountered in the daily practice, especially regarding the diagnosis of the diffuse paediatric-type high-grade glioma H3-wildtype and IDH-wildtype. The advantages and the limits of the multiple molecular tests which may be utilised to define the entities of this tumour family will be evaluated in each diagnostic context.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Criança , Mutação , Glioma/diagnóstico , Organização Mundial da Saúde
11.
Contact Dermatitis ; 2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33713466

RESUMO

BACKGROUND: Exposure to nickel-releasing ear-piercing jewellery may explain the persistently high prevalence of nickel allergy in Europe. While nickel release from earrings is regulated, field studies show that the regulation is not always respected. More knowledge is needed regarding the risk of piercing exposure including suitable screening methods. OBJECTIVE: To examine the proportion of earrings on the Danish market that release more nickel than allowed, and to validate the use of the dimethylglyoxime (DMG) test as a screening tool. METHODS: A total of 304 earrings were purchased and tested with the DMG test and X-ray fluorescence spectrometry. The level of nickel release was quantified in a selected subsample of 100 earrings by the European reference test EN 1811. The DMG spot test was validated against EN 1811 at different thresholds. RESULTS: Excessive nickel release according to the European regulation was found in 45 (14.8%) tested earrings. The sensitivity of the DMG test decreased with reduced levels of nickel release (sensitivity of 45.2% at ≥0.2 µg/cm2 /week vs 61.1% at >0.5 µg/cm2 /week). CONCLUSION: Excessive nickel release is common in earrings on the Danish market. Because of low sensitivity, the DMG test has limited use in screening of earrings for research but may still be used clinically.

12.
Adv Exp Med Biol ; 1283: 73-84, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33155139

RESUMO

Diffuse intrinsic pontine glioma (DIPG) is a lethal midline brainstem tumor that most commonly occurs in children and is genetically defined by substitution of methionine for lysine at site 27 of histone 3 (H3K27M) in the majority of cases. This mutation has since been shown to exert an influence on the posttranslational epigenetic landscape of this disease, with the loss of trimethylation at lysine 27 (H3K27me3) the most common alteration. Based on these findings, a number of drugs targeting these epigenetic changes have been proposed, specifically that alter histone trimethylation, acetylation, or phosphorylation. Various mechanisms have been explored, including inhibition of H327 demethylase and methyltransferase to target trimethylation, inhibition of histone deacetylase (HDAC) and bromodomain and extraterminal (BET) to target acetylation, and inhibition of phosphatase-related enzymes to target phosphorylation. This chapter reviews the current rationales and progress made to date in epigenetically targeting DIPG via these mechanisms.


Assuntos
Neoplasias do Tronco Encefálico , Epigênese Genética , Glioma , Histonas/genética , Neoplasias do Tronco Encefálico/genética , Criança , Glioma/tratamento farmacológico , Glioma/genética , Histonas/metabolismo , Humanos , Mutação , Processamento de Proteína Pós-Traducional
13.
J Neuroradiol ; 48(4): 243-247, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32184119

RESUMO

BACKGROUND: Diffuse midline gliomas (DMG) are aggressive brain tumours, previously known as diffuse intrinsic pontine gliomas (DIPG), with 10% overall survival (OS) at 18 months. Predicting OS will help refine treatment strategy in this patient group. MRI based texture analysis (MRTA) is novel image analysis technique that provides objective information about spatial arrangement of MRI signal intensity (heterogeneity) and has potential to be imaging biomarker. OBJECTIVES: To investigate MRTA in predicting OS in childhood DMG. METHODS: Retrospective study of patients diagnosed with DMG, based on radiological features, treated at our institution 2007-2017. MRIs were acquired at diagnosis and 6 weeks after radiotherapy (54Gy in 30 fractions). MRTA was performed using commercial available TexRAD research software on T2W sequence and Apparent Diffusion Coefficient (ADC) maps encapsulating tumour in the largest single axial plane. MRTA comprised filtration-histogram technique using statistical and histogram metrics for quantification of texture. Kaplan-Meier survival analysis determined association of MRI texture parameters with OS. RESULTS: In all, 32 children 2-14 years (median 7 years) were included. MRTA was undertaken on T2W (n=32) and ADC (n=22). T2W-MRTA parameters were better at prognosticating than ADC-MRTA. Children with homogenous tumour texture, at medium scale on diagnostic T2W MRI, had worse prognosis (Mean of Positive Pixels (MPP): P=0.005, mean: P=0.009, SD: P=0.011, kurtosis: P=0.037, entropy: P=0.042). Best predictor MPP was able to stratify patients into poor and good prognostic groups with median survival of 7.5 months versus 17.5 months, respectively. CONCLUSIONS: DMG with more homogeneous texture on diagnostic MRI is associated with worse prognosis. Texture parameter MPP is the most predictive marker of OS in childhood DMG.


Assuntos
Neoplasias do Tronco Encefálico , Glioma , Criança , Imagem de Difusão por Ressonância Magnética , Glioma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos
14.
J Bacteriol ; 202(24)2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32817090

RESUMO

Fluctuations in osmolarity are one of the most prevalent stresses to which bacteria must adapt, both hypo- and hyperosmotic conditions. Most bacteria cope with high osmolarity by accumulating compatible solutes (osmolytes) in the cytoplasm to maintain the turgor pressure of the cell. Vibrio parahaemolyticus, a halophile, utilizes at least six compatible solute transporters for the uptake of osmolytes: two ABC family ProU transporters and four betaine-carnitine-choline transporter (BCCT) family transporters. The full range of compatible solutes transported by this species has yet to be determined. Using an osmolyte phenotypic microarray plate for growth analyses, we expanded the known osmolytes used by V. parahaemolyticus to include N,N-dimethylglycine (DMG), among others. Growth pattern analysis of four triple-bccT mutants, possessing only one functional BCCT, indicated that BccT1 (VP1456), BccT2 (VP1723), and BccT3 (VP1905) transported DMG. BccT1 was unusual in that it could take up both compounds with methylated head groups (glycine betaine [GB], choline, and DMG) and cyclic compounds (ectoine and proline). Bioinformatics analysis identified the four coordinating amino acid residues for GB in the BccT1 protein. In silico modeling analysis demonstrated that GB, DMG, and ectoine docked in the same binding pocket in BccT1. Using site-directed mutagenesis, we showed that a strain with all four residues mutated resulted in the loss of uptake of GB, DMG, and ectoine. We showed that three of the four residues were essential for ectoine uptake, whereas only one of the residues was important for GB uptake. Overall, we have demonstrated that DMG is a highly effective compatible solute for Vibrio species and have elucidated the amino acid residues in BccT1 that are important for the coordination of GB, DMG, and ectoine transport.IMPORTANCEVibrio parahaemolyticus possesses at least six osmolyte transporters, which allow the bacterium to adapt to high-salinity conditions. In this study, we identified several additional osmolytes that were utilized by V. parahaemolyticus We demonstrated that the compound DMG, which is present in the marine environment, was a highly effective osmolyte for Vibrio species. We determined that DMG is transported via BCCT family carriers, which have not been shown previously to take up this compound. BccT1 was a carrier for GB, DMG, and ectoine, and we identified the amino acid residues essential for the coordination of these compounds. The data suggest that for BccT1, GB is more easily accommodated than ectoine in the transporter binding pocket.


Assuntos
Diamino Aminoácidos/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Sarcosina/análogos & derivados , Vibrio parahaemolyticus/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Betaína/metabolismo , Transporte Biológico , Carnitina/metabolismo , Colina/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/genética , Família Multigênica , Sarcosina/metabolismo , Vibrio parahaemolyticus/química , Vibrio parahaemolyticus/genética
15.
J Neurooncol ; 149(3): 511-522, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33034839

RESUMO

PURPOSE: Cyclin-dependent kinase-retinoblastoma (CDK-RB) pathway is dysregulated in some diffuse intrinsic pontine gliomas (DIPG). We evaluated safety, feasibility, and early efficacy of the CDK4/6-inhibitor ribociclib, administered following radiotherapy in newly-diagnosed DIPG patients. METHODS: Following radiotherapy, eligible patients received ribociclib in 28-day cycles (350 mg/m2; 21 days on/7 days off). Feasibility endpoints included tolerability for at least 6 courses, and a less than 2-week delay in restarting therapy after 1 dose reduction. Early efficacy was measured by 1-year and median overall survival (OS). Patient/parent-by-proxy reported outcomes measurement information system (PROMIS) assessments were completed prospectively. RESULTS: The study included 10 evaluable patients, 9 DIPG and 1 diffuse midline glioma (DMG)-all 3.7 to 19.8 years of age. The median number of courses was 8 (range 3-14). Three patients required dose reduction for grade-4 neutropenia, and 1 discontinued therapy for hematological toxicity following course 4. The most common grade-3/4 toxicity was myelosuppression. After 2 courses, MRI evaluations in 4 patients revealed increased necrotic volume, associated with new neurological symptoms in 3 patients. The 1-year and median OS for DIPG was 89% and 16.1 months (range 10-30), respectively; the DMG patient died at 6 months post-diagnosis. Five patients donated brain tissue and tumor; 3 were RB+ . CONCLUSIONS: Ribociclib administered following radiotherapy is feasible in DIPG and DMG. Increased tumor necrosis may represent a treatment effect. These data warrant further prospective volumetric analyses of tumors with necrosis. Feasibility and stabilization findings support further investigation of ribociclib in combination therapies. TRIAL REGISTRATION: NCT02607124.


Assuntos
Aminopiridinas/uso terapêutico , Neoplasias do Tronco Encefálico/terapia , Quimiorradioterapia/métodos , Glioma Pontino Intrínseco Difuso/terapia , Purinas/uso terapêutico , Adolescente , Adulto , Aminopiridinas/farmacocinética , Neoplasias do Tronco Encefálico/patologia , Criança , Pré-Escolar , Glioma Pontino Intrínseco Difuso/patologia , Feminino , Seguimentos , Humanos , Masculino , Dose Máxima Tolerável , Prognóstico , Purinas/farmacocinética , Distribuição Tecidual , Adulto Jovem
16.
Neurosurg Focus ; 48(1): E4, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31896081

RESUMO

Diffuse intrinsic pontine glioma (DIPG) is a universally fatal pediatric brainstem tumor affecting approximately 300 children in the US annually. Median survival is less than 1 year, and radiation therapy has been the mainstay of treatment for decades. Recent advances in the biological understanding of the disease have identified the H3K27M mutation in nearly 80% of DIPGs, leading to the 2016 WHO classification of diffuse midline glioma H3K27M-mutant, a grade IV brainstem tumor. Developments in epigenetic targeting of transcriptional tendencies have yielded potential molecular targets for clinical trials. Chimeric antigen receptor T cell therapy has also shown preclinical promise. Recent clinical studies, including prospective trials, have demonstrated the safety and feasibility of pediatric brainstem biopsy in the setting of DIPG and other brainstem tumors. Given developments in the ability to analyze DIPG tumor tissue to deepen biological understanding of this disease and develop new therapies for treatment, together with the increased safety of stereotactic brainstem biopsy, the authors present a case for offering biopsy to all children with suspected DIPG. They also present their standard operative techniques for image-guided, frameless stereotactic biopsy.


Assuntos
Astrocitoma , Biópsia , Neoplasias do Tronco Encefálico , Padrão de Cuidado , Astrocitoma/patologia , Astrocitoma/cirurgia , Biópsia/métodos , Neoplasias do Tronco Encefálico/patologia , Neoplasias do Tronco Encefálico/cirurgia , Criança , Pré-Escolar , Epigenômica , Glioma/genética , Humanos , Biópsia Guiada por Imagem/métodos , Estudos Prospectivos
17.
Neurosurg Focus ; 48(1): E9, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31896079

RESUMO

Diffuse midline glioma (DMG) is a highly malignant childhood tumor with an exceedingly poor prognosis and limited treatment options. The majority of these tumors harbor somatic mutations in genes encoding histone variants. These recurrent mutations correlate with treatment response and are forming the basis for molecularly guided clinical trials. The ability to detect these mutations, either in circulating tumor DNA (ctDNA) or cerebrospinal fluid tumor DNA (CSF-tDNA), may enable noninvasive molecular profiling and earlier prediction of treatment response. Here, the authors review ctDNA and CSF-tDNA detection methods, detail recent studies that have explored detection of ctDNA and CSF-tDNA in patients with DMG, and discuss the implications of liquid biopsies for patients with DMG.


Assuntos
Neoplasias Encefálicas/diagnóstico , DNA Tumoral Circulante/líquido cefalorraquidiano , Glioma/diagnóstico , Biópsia Líquida , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/líquido cefalorraquidiano , Neoplasias Encefálicas/patologia , DNA/genética , Glioma/líquido cefalorraquidiano , Humanos , Biópsia Líquida/métodos
18.
Biochem Biophys Res Commun ; 512(4): 742-749, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-30926168

RESUMO

High temperature stress has become a major concern for crop production worldwide because it greatly affects the growth, development, and productivity of plants. The mechanisms underlying the development of heat-tolerance need to be better understood for important agricultural crops. Recent research shows that DNA methylation is dynamic during plant development. However, the molecular mechanism regulating these dynamic DNA methylation patterns remains to be elucidated. In this study, six MethylRAD libraries were constructed using DNA isolated from leaves of maize. A total of 42,561,144 and 48,157,284 clean reads were generated from CK (Control condition) and HTP (Heat stress condition) treatments, respectively. The results showed that a total of 25,470 methylated genes were found in six tested samples, including 325 differentially methylated genes (200 in CCGG sites and 125 in CCWGG sites) between the CK and HTP samples. KEGG pathway enrichment analysis for DMGs indicated that Spliceosome, Homologous recombination, RNA transport, Ubiquitin mediated proteolysis and Carbon metabolism pathways play a central role in maize response to heat stress. Taken together, this research revealed the genome-wide DNA methylation pattern of maize leaves in response to heat exposure and identified candidate genes potentially involved in response to heat stress at the methylation level, which will facilitate future studies to elucidate the epigenetic mechanisms underlying the responses of maize to heat stress.


Assuntos
Metilação de DNA , Regulação da Expressão Gênica de Plantas , Plântula/genética , Zea mays/genética , DNA de Plantas/genética , Epigênese Genética , Resposta ao Choque Térmico , Proteínas de Plantas/genética , Plântula/fisiologia , Zea mays/fisiologia
19.
J Neurooncol ; 145(1): 177-184, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31522324

RESUMO

INTRODUCTION: Diffuse intrinsic pontine glioma (DIPG) is a rare clinically, neuro-radiologically, and molecularly defined malignancy of the brainstem with a median overall survival of approximately 11 months. Our aim is to evaluate the current tendency for its treatment in Europe in order to develop (inter)national consensus guidelines. METHODS: Healthcare professionals specialized in DIPG were asked to fill in an online survey with questions regarding usual treatment strategies at diagnosis and at disease progression in their countries and/or their centers, respectively. RESULTS: Seventy-four healthcare professionals responded to the survey, of which 87.8% were pediatric oncologists. Only 13.5% of the respondents biopsy all of their patients, 41.9% biopsy their patients infrequently. More than half of the respondents (54.1%) treated their patients with radiotherapy only at diagnosis, whereas 44.6% preferred radiotherapy combined with chemotherapy. When the disease progresses, treatment strategies became even more diverse, and the tendency for no treatment increased from 1.4% at diagnosis to 77.0% after second progression. 36.5% of the healthcare professionals treat children younger than 3 years differently than older children at diagnosis. This percentage decreased, when the disease progresses. Most of the participants (51.4%) included less than 25% of their patients in clinical trials. CONCLUSION: This survey demonstrates a large heterogeneity of treatment regimens, especially at disease progression. We emphasize the need for international consensus guidelines for the treatment of DIPG, possible by more collaborative clinical trials.


Assuntos
Neoplasias do Tronco Encefálico/diagnóstico , Neoplasias do Tronco Encefálico/terapia , Glioma Pontino Intrínseco Difuso/diagnóstico , Glioma Pontino Intrínseco Difuso/terapia , Biópsia , Terapia Combinada , Progressão da Doença , Humanos , Prognóstico
20.
Br J Nutr ; 121(11): 1279-1286, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30837009

RESUMO

Maternal one-carbon metabolism during pregnancy is crucial for fetal development and programming by DNA methylation. However, evidence on one-carbon biomarkers other than folate is lacking. We, therefore, investigated whether maternal plasma methyl donors, that is, choline, betaine and methionine, are associated with birth outcomes. Blood samples were obtained from 115 women during gestation (median 26·3 weeks, 90 % range 22·7-33·0 weeks). Plasma choline, betaine, methionine and dimethylglycine were measured using HPLC-tandem MS. Multivariate linear and logistic regression models were used to estimate the association between plasma biomarkers and birth weight, birth length, the risk of small-for-gestational-age and large-for-gestational-age (LGA). Higher level of maternal betaine was associated with lower birth weight (-130·3 (95 % CI -244·8, -15·9) per 1 sd increment for log-transformed betaine). Higher maternal methionine was associated with lower risk of LGA, and adjusted OR, with 95 % CI for 1 sd increase in methionine concentration was 0·44 (95 % CI 0·21, 0·89). Stratified analyses according to infant sex or maternal plasma homocysteine status showed that reduction in birth weight in relation to maternal betaine was only limited to male infants or to who had higher maternal homocysteine status (≥5·1 µmol/l). Higher maternal betaine status was associated with reduced birth weight. Maternal methionine was inversely associated with LGA risk. These findings are needed to be replicated in future larger studies.


Assuntos
Betaína/sangue , Peso ao Nascer , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Trimestres da Gravidez/sangue , Adulto , Colina/sangue , Feminino , Homocisteína/sangue , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Masculino , Metionina/sangue , Gravidez , Sarcosina/análogos & derivados , Sarcosina/sangue
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