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1.
ACS Appl Mater Interfaces ; 11(42): 38483-38496, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31537060

RESUMO

In this work, we designed, characterized, and investigated the performance of hydrolyzed galactomannan (hGM)-based amphiphilic nanoparticles for selective intratumoral accumulation in pediatric patient-derived sarcomas. To create a self-assembly amphiphilic copolymer, the side chain of hGM was hydrophobized with poly(methyl methacrylate) (PMMA) by utilizing a graft free radical polymerization reaction. Different hGM and MMA weight feeding ratios were used to adjust the critical aggregation concentration and the size and size distribution of the nanoparticles. The ability to actively target glucose transporter-1 (GLUT-1) was studied by fluorescence confocal microscopy and imaging flow cytometry in vitro on Rh30 (rhabdomyosarcoma) and patient-derived Ewing sarcoma (HSJD-ES-001) cell lines with different expression levels of GLUT-1. Results confirmed that the nanoparticles are internalized by ∼100% of the cells at 37 °C. Furthermore, we investigated the biodistribution of the nanoparticles in pediatric patient-derived models of two deadly musculoskeletal tumors, rhabdomyosarcoma and Ewing sarcoma. Outstandingly, the intratumoral accumulation of the nanoparticles correlated very well with the expression level of GLUT1 gene in each patient-derived tumor (P = 0.0141; Pearson's correlation test). Finally, we demonstrated the encapsulation capacity of these nanoparticles by loading 7.5% (w/w) of the hydrophobic first-generation tyrosine kinase inhibitor imatinib. These findings point out the potential of this new type of nanoparticle to target GLUT-1-expressing tumors and selectively deliver anticancer agents.

2.
Acta Neuropathol ; 138(6): 1053-1074, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31428936

RESUMO

Tumors have aberrant proteomes that often do not match their corresponding transcriptome profiles. One possible cause of this discrepancy is the existence of aberrant RNA modification landscapes in the so-called epitranscriptome. Here, we report that human glioma cells undergo DNA methylation-associated epigenetic silencing of NSUN5, a candidate RNA methyltransferase for 5-methylcytosine. In this setting, NSUN5 exhibits tumor-suppressor characteristics in vivo glioma models. We also found that NSUN5 loss generates an unmethylated status at the C3782 position of 28S rRNA that drives an overall depletion of protein synthesis, and leads to the emergence of an adaptive translational program for survival under conditions of cellular stress. Interestingly, NSUN5 epigenetic inactivation also renders these gliomas sensitive to bioactivatable substrates of the stress-related enzyme NQO1. Most importantly, NSUN5 epigenetic inactivation is a hallmark of glioma patients with long-term survival for this otherwise devastating disease.

3.
Nat Commun ; 10(1): 3790, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31439867

RESUMO

Pediatric high-grade gliomas are among the deadliest of childhood cancers due to limited knowledge of early driving events in their gliomagenesis and the lack of effective therapies available. In this study, we investigate the oncogenic role of PPM1D, a protein phosphatase often found truncated in pediatric gliomas such as DIPG, and uncover a synthetic lethal interaction between PPM1D mutations and nicotinamide phosphoribosyltransferase (NAMPT) inhibition. Specifically, we show that mutant PPM1D drives hypermethylation of CpG islands throughout the genome and promotes epigenetic silencing of nicotinic acid phosphoribosyltransferase (NAPRT), a key gene involved in NAD biosynthesis. Notably, PPM1D mutant cells are shown to be sensitive to NAMPT inhibitors in vitro and in vivo, within both engineered isogenic astrocytes and primary patient-derived model systems, suggesting the possible application of NAMPT inhibitors for the treatment of pediatric gliomas. Overall, our results reveal a promising approach for the targeting of PPM1D mutant tumors, and define a critical link between oncogenic driver mutations and NAD metabolism, which can be exploited for tumor-specific cell killing.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Tronco Encefálico/genética , Nicotinamida Fosforribosiltransferase/genética , Proteína Fosfatase 2C/genética , Animais , Antineoplásicos/uso terapêutico , Neoplasias do Tronco Encefálico/tratamento farmacológico , Neoplasias do Tronco Encefálico/patologia , Linhagem Celular Tumoral , Criança , Citocinas/antagonistas & inibidores , Metilação de DNA , /patologia , Repressão Epigenética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Nicotinamida Fosforribosiltransferase/antagonistas & inibidores , Nicotinamida Fosforribosiltransferase/metabolismo , Ponte/citologia , Ponte/patologia , Cultura Primária de Células , Proteína Fosfatase 2C/metabolismo , Mutações Sintéticas Letais , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Cancer Res ; 79(16): 4026-4041, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31201162

RESUMO

Diffuse intrinsic pontine gliomas (DIPG) are incurable brain tumors with an aggressive onset. Apart from irradiation, there are currently no effective therapies available for patients with DIPG, who have a median survival time of less than one year. Most DIPG cells harbor mutations in genes encoding histone H3 (H3K27M) proteins, resulting in a global reduction of H3K27 trimethylation and activation of oncogenic signaling pathways. Here we show that the H3K27M mutations contribute to RAS pathway signaling, which is augmented by additional RAS activators including PDGFRA. H3K27M mutation led to increased expression of receptor tyrosine kinases (RTK). A RAS pathway functional screen identified ERK5, but not ERK1/2, as a RAS pathway effector important for DIPG growth. Suppression of ERK5 decreased DIPG cell proliferation and induced apoptosis in vitro and in vivo. In addition, depletion or inhibition of ERK5 significantly increased survival of mice intracranially engrafted with DIPG cells. Mechanistically, ERK5 directly stabilized the proto-oncogene MYC at the protein level. Collectively, our data demonstrate an underappreciated role of H3K27M in RAS activation and reveal novel therapeutic targets for treating DIPG tumors. SIGNIFICANCE: These findings identify the H3K27M mutation as an enhancer of RAS activation in DIPG and ERK5 as a novel, immediately actionable molecular target. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/16/4026/F1.large.jpg.

5.
Clin Cancer Res ; 25(18): 5572-5583, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31227500

RESUMO

PURPOSE: Radiotherapy (RT) has long been and remains the only treatment option for diffuse intrinsic pontine glioma (DIPG). However, all patients show evidence of disease progression within months of completing RT. No further clinical benefit has been achieved using alternative radiation strategies. Here, we tested the hypothesis that histone demethylase inhibition by GSK-J4 enhances radiation-induced DNA damage, making it a potential radiosensitizer in the treatment of DIPG.Experimental Design: We evaluated the effects of GSK-J4 on genes associated with DNA double-strand break (DSB) repair in DIPG cells by RNA sequence, ATAC sequence, and quantitative real-time PCR. Radiation-induced DNA DSB repair was analyzed by immunocytochemistry of DSB markers γH2AX and 53BP1, DNA-repair assay, and cell-cycle distribution. Clonogenic survival assay was used to determine the effect of GSK-J4 on radiation response of DIPG cells. In vivo response to radiation monotherapy and combination therapy of RT and GSK-J4 was evaluated in patient-derived DIPG xenografts. RESULTS: GSK-J4 significantly reduced the expression of DNA DSB repair genes and DNA accessibility in DIPG cells. GSK-J4 sustained high levels of γH2AX and 53BP1 in irradiated DIPG cells, thereby inhibiting DNA DSB repair through homologous recombination pathway. GSK-J4 reduced clonogenic survival and enhanced radiation effect in DIPG cells. In vivo studies revealed increased survival of animals treated with combination therapy of RT and GSK-J4 compared with either monotherapy. CONCLUSIONS: Together, these results highlight GSK-J4 as a potential radiosensitizer and provide a rationale for developing combination therapy with radiation in the treatment of DIPG.

6.
Int J Mol Sci ; 20(5)2019 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-30832308

RESUMO

A preclinical model could aid in understanding retinoblastoma vitreous seeds behavior, drug penetration, and response to chemotherapy to optimize patient treatment. Our aim was to develop a tridimensional in vitro model of retinoblastoma vitreous seeds to assess chemotherapy penetration by means of live-cell imaging. Cell cultures from patients with retinoblastoma who underwent upfront enucleation were established and thoroughly characterized for authentication of human tumor origin. The correlation of the in vitro tridimensional structures resembling human spheres and dusts vitreous seeds was established. Confocal microscopy was used to quantify real-time fluorescence of topotecan as a measure of its penetration into different sizes of spheres. Cell viability was determined after chemotherapy penetration. The in vitro spheres and dusts models were able to recapitulate the morphology, phenotype, and genotype of patient vitreous seeds. The larger the size of the spheres, the longer the time required for the drug to fully penetrate into the core (p < 0.05). Importantly, topotecan penetration correlated with its cytotoxic activity. Therefore, the studied tridimensional cell model recapitulated several characteristics of vitreous seeds observed in patients with retinoblastoma and were successfully used to assess live-cell imaging of chemotherapy penetration for drug distribution studies.


Assuntos
Antineoplásicos/farmacologia , Organoides/efeitos dos fármacos , Retinoblastoma/tratamento farmacológico , Topotecan/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Células Cultivadas , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Humanos , Imagem Tridimensional/métodos , Organoides/diagnóstico por imagem , Cultura Primária de Células/métodos , Topotecan/uso terapêutico
7.
Sci Transl Med ; 11(476)2019 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-30674657

RESUMO

Retinoblastoma is a pediatric solid tumor of the retina activated upon homozygous inactivation of the tumor suppressor RB1 VCN-01 is an oncolytic adenovirus designed to replicate selectively in tumor cells with high abundance of free E2F-1, a consequence of a dysfunctional RB1 pathway. Thus, we reasoned that VCN-01 could provide targeted therapeutic activity against even chemoresistant retinoblastoma. In vitro, VCN-01 effectively killed patient-derived retinoblastoma models. In mice, intravitreous administration of VCN-01 in retinoblastoma xenografts induced tumor necrosis, improved ocular survival compared with standard-of-care chemotherapy, and prevented micrometastatic dissemination into the brain. In juvenile immunocompetent rabbits, VCN-01 did not replicate in retinas, induced minor local side effects, and only leaked slightly and for a short time into the blood. Initial phase 1 data in patients showed the feasibility of the administration of intravitreous VCN-01 and resulted in antitumor activity in retinoblastoma vitreous seeds and evidence of viral replication markers in tumor cells. The treatment caused local vitreous inflammation but no systemic complications. Thus, oncolytic adenoviruses targeting RB1 might provide a tumor-selective and chemotherapy-independent treatment option for retinoblastoma.

8.
Oncogene ; 38(12): 2056-2075, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30401983

RESUMO

Retinoblastoma is the most common intraocular cancer in children. While the primary tumor can often be treated by local or systemic chemotherapy, metastatic dissemination is generally resistant to therapy and remains a leading cause of pediatric cancer death in much of the world. In order to identify new therapeutic targets in aggressive tumors, we sequenced RNA transcripts in five snap frozen retinoblastomas which invaded the optic nerve and five which did not. A three-fold increase was noted in mRNA levels of ACVR1C/ALK7, a type I receptor of the TGF-ß family, in invasive retinoblastomas, while downregulation of DACT2 and LEFTY2, negative modulators of the ACVR1C signaling, was observed in most invasive tumors. A two- to three-fold increase in ACVR1C mRNA was also found in invasive WERI Rb1 and Y79 cells as compared to non-invasive cells in vitro. Transcripts of ACVR1C receptor and its ligands (Nodal, Activin A/B, and GDF3) were expressed in six retinoblastoma lines, and evidence of downstream SMAD2 signaling was present in all these lines. Pharmacological inhibition of ACVR1C signaling using SB505124, or genetic downregulation of the receptor using shRNA potently suppressed invasion, growth, survival, and reduced the protein levels of the mesenchymal markers ZEB1 and Snail. The inhibitory effects on invasion, growth, and proliferation were recapitulated by knocking down SMAD2, but not SMAD3. Finally, in an orthotopic zebrafish model of retinoblastoma, a 55% decrease in tumor spread was noted (p = 0.0026) when larvae were treated with 3 µM of SB505124, as compared to DMSO. Similarly, knockdown of ACVR1C in injected tumor cells using shRNA also resulted in a 54% reduction in tumor dissemination in the zebrafish eye as compared to scrambled shRNA control (p = 0.0005). Our data support a role for the ACVR1C/SMAD2 pathway in promoting invasion and growth of retinoblastoma.


Assuntos
Receptores de Ativinas Tipo I/metabolismo , Retinoblastoma/patologia , Transdução de Sinais , Proteína Smad2/metabolismo , Receptores de Ativinas Tipo I/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Fenótipo , Proteína Smad2/genética
9.
Clin Cancer Res ; 25(7): 2228-2240, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30420447

RESUMO

PURPOSE: Endoglin (ENG; CD105) is a coreceptor of the TGFß family that is highly expressed in proliferating endothelial cells. Often coopted by cancer cells, ENG can lead to neo-angiogenesis and vasculogenic mimicry in aggressive malignancies. It exists both as a transmembrane cell surface protein, where it primarily interacts with TGFß, and as a soluble matricellular protein (sENG) when cleaved by matrix metalloproteinase 14 (MMP14). High ENG expression has been associated with poor prognosis in Ewing sarcoma, an aggressive bone cancer that primarily occurs in adolescents and young adults. However, the therapeutic value of ENG targeting has not been fully explored in this disease. EXPERIMENTAL DESIGN: We characterized the expression pattern of transmembrane ENG, sENG, and MMP14 in preclinical and clinical samples. Subsequently, the antineoplastic potential of two novel ENG-targeting monoclonal antibody-drug conjugates (ADC), OMTX503 and OMTX703, which differed only by their drug payload (nigrin-b A chain and cytolysin, respectively), was assessed in cell lines and preclinical animal models of Ewing sarcoma. RESULTS: Both ADCs suppressed cell proliferation in proportion to the endogenous levels of ENG observed in vitro. Moreover, the ADCs significantly delayed tumor growth in Ewing sarcoma cell line-derived xenografts and patient-derived xenografts in a dose-dependent manner. CONCLUSIONS: Taken together, these studies demonstrate potent preclinical activity of first-in-class anti-ENG ADCs as a nascent strategy to eradicate Ewing sarcoma.

10.
Oncotarget ; 9(59): 31397-31410, 2018 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30140378

RESUMO

Purpose: Epigenetic regulation is crucial in mammalian development and maintenance of tissue-cell specific functions. Perturbation of epigenetic balance may lead to alterations in gene expression, resulting in cellular transformation and malignancy. Previous studies in Ewing sarcoma (ES) have shown that the Nucleosome Remodeling Deacetylase (NuRD) complex binds directly to EWS-FLI1 oncoprotein and modulates its transcriptional activity. The role of EWS-FLI1 as a driver of proliferation and transformation in ES is widely known, but the effect of epigenetic drugs on fusion activity remains poorly described. The present study evaluated the combination effects of the histone deacetylases inhibitor suberoylanilide hydroxamic acid (SAHA) and Lysine-specific demethylase1 inhibitor (HCI-2509) on different biological functions in ES and in comparison to monotherapy treatments. Results: The study of proliferation and cell viability showed a synergistic effect in most ES cell lines analyzed. An enhanced effect was also observed in the induction of apoptosis, together with accumulation of cells in G1 phase and a blockage of the migratory capacity of ES cell lines. Treatment, either in monotherapy or in combination, caused a significant decrease of EWS-FLI1 mRNA and protein levels and this effect is mediated in part by fusion gene promoter regulation. The anti-tumor effect of this combination was confirmed in patient-derived xenograft mouse models, in which only the combination treatment led to a statistically significant decrease in tumor volume. Conclusions: The combination of SAHA and HCI-2509 is proposed as a novel treatment strategy for ES patients to inhibit the essential driver of this sarcoma and tumor growth.

12.
Nat Med ; 24(8): 1204-1215, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29967352

RESUMO

The failure to develop effective therapies for pediatric glioblastoma (pGBM) and diffuse intrinsic pontine glioma (DIPG) is in part due to their intrinsic heterogeneity. We aimed to quantitatively assess the extent to which this was present in these tumors through subclonal genomic analyses and to determine whether distinct tumor subpopulations may interact to promote tumorigenesis by generating subclonal patient-derived models in vitro and in vivo. Analysis of 142 sequenced tumors revealed multiple tumor subclones, spatially and temporally coexisting in a stable manner as observed by multiple sampling strategies. We isolated genotypically and phenotypically distinct subpopulations that we propose cooperate to enhance tumorigenicity and resistance to therapy. Inactivating mutations in the H4K20 histone methyltransferase KMT5B (SUV420H1), present in <1% of cells, abrogate DNA repair and confer increased invasion and migration on neighboring cells, in vitro and in vivo, through chemokine signaling and modulation of integrins. These data indicate that even rare tumor subpopulations may exert profound effects on tumorigenesis as a whole and may represent a new avenue for therapeutic development. Unraveling the mechanisms of subclonal diversity and communication in pGBM and DIPG will be an important step toward overcoming barriers to effective treatments.


Assuntos
Neoplasias do Tronco Encefálico/patologia , Glioblastoma/patologia , Animais , Neoplasias do Tronco Encefálico/genética , Carcinogênese/patologia , Separação Celular , Criança , Células Clonais , Genótipo , Glioblastoma/genética , Humanos , Camundongos Nus , Fenótipo , Células Tumorais Cultivadas
14.
Adv Healthc Mater ; 7(15): e1800255, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29892999

RESUMO

Delivery of chemotherapy in the surgical bed has shown preclinical activity to control cancer progression upon subtotal resection of pediatric solid tumors, but whether this new treatment is safe for tumor-adjacent healthy tissues remains unknown. Here, Wistar rats are used to study the anatomic and functional impact of electrospun nanofiber matrices eluting SN-38-a potent chemotherapeutic agent-on several body sites where pediatric tumors such as neuroblastoma, Ewing sarcoma, and rhabdomyosarcoma arise. Blank and SN-38-loaded matrices embracing the femoral neurovascular bundle or in direct contact with abdominal viscera (liver, kidney, urinary bladder, intestine, and uterus) are placed. Foreign body tissue reaction to the implants is observed though no histologic damage in any tissue/organ. Skin healing is normal. Tissue reaction is similar for SN-38-loaded and blank matrices, with the exception of the hepatic capsule that is thicker for the former although within the limits consistent with mild foreign body reaction. Tissue and organ function is completely conserved after local treatments, as assessed by the rotarod test (forelimb function), hematologic tests (liver and renal function), and control of clinical signs. Overall, these findings support the clinical translation of SN-38-loaded nanofiber matrices to improve local control strategies of surgically resected tumors.


Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Irinotecano/química , Nanofibras/química , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Ratos Wistar , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/metabolismo
15.
Front Oncol ; 8: 127, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29755954

RESUMO

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

16.
Science ; 360(6386): 331-335, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29674595

RESUMO

Gliomas with histone H3 lysine27-to-methionine mutations (H3K27M-glioma) arise primarily in the midline of the central nervous system of young children, suggesting a cooperation between genetics and cellular context in tumorigenesis. Although the genetics of H3K27M-glioma are well characterized, their cellular architecture remains uncharted. We performed single-cell RNA sequencing in 3321 cells from six primary H3K27M-glioma and matched models. We found that H3K27M-glioma primarily contain cells that resemble oligodendrocyte precursor cells (OPC-like), whereas more differentiated malignant cells are a minority. OPC-like cells exhibit greater proliferation and tumor-propagating potential than their more differentiated counterparts and are at least in part sustained by PDGFRA signaling. Our study characterizes oncogenic and developmental programs in H3K27M-glioma at single-cell resolution and across genetic subclones, suggesting potential therapeutic targets in this disease.


Assuntos
Neoplasias Encefálicas/patologia , Carcinogênese/genética , Glioma/patologia , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Oncogenes , Neoplasias Encefálicas/genética , Proliferação de Células , Glioma/genética , Histonas/metabolismo , Humanos , Proteína Quinase 7 Ativada por Mitógeno/genética , Mutação , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos
17.
J Control Release ; 276: 59-71, 2018 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-29501533

RESUMO

We report for the first time on a nano-drug delivery system based on glucosylated polymeric nanomicelles to actively target the second-generation tyrosine kinase inhibitor dasatinib to glucose-avid pediatric sarcomas by the intravenous route. After a comprehensive physicochemical characterization that confirmed the substantially lower critical micellar concentration and the higher encapsulation capacity of the glucosylated amphiphilic nanocarrier with respect to the pristine counterpart, we showed a 9-fold decrease of the half maximal inhibitory concentration of dasatinib in a rhabdomyosarcoma cell line, Rh30, in vitro. In immunodeficient mice bearing the glucose-avid Rh30 xenograft, we revealed that the glucosylated polymeric nanomicelles increased the delivery of dasatinib in the tumor parenchyma. Conversely, the exposure of off-target tissues and organs to the drug was substantially reduced. Upon experimental confirmation that most patient-derived xenograft (PDX) models of pediatric sarcomas overexpress glucose transporter 1 (GLUT-1), we demonstrated the selective accumulation of dasatinib in a patient-derived rhabdomyosarcoma model in vivo. Conversely, the reference dose administered by the oral route was not tumor-selective. Finally, the improved nanocarrier pharmacokinetics led to prolonged median survival of mice bearing a clinically relevant PDX model of alveolar rhabdomyosarcoma from 19 days for the untreated controls to 27 days for the targeted therapy.


Assuntos
Antineoplásicos/administração & dosagem , Dasatinibe/administração & dosagem , Micelas , Nanoestruturas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Criança , Dasatinibe/farmacocinética , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Humanos , Camundongos Nus , Inibidores de Proteínas Quinases/farmacocinética , Sarcoma/tratamento farmacológico , Sarcoma/genética , Sarcoma/metabolismo
18.
Clin Cancer Res ; 24(6): 1355-1363, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29351917

RESUMO

Purpose: The classification of medulloblastoma into WNT, SHH, group 3, and group 4 subgroups has become of critical importance for patient risk stratification and subgroup-tailored clinical trials. Here, we aimed to develop a simplified, clinically applicable classification approach that can be implemented in the majority of centers treating patients with medulloblastoma.Experimental Design: We analyzed 1,577 samples comprising previously published DNA methylation microarray data (913 medulloblastomas, 457 non-medulloblastoma tumors, 85 normal tissues), and 122 frozen and formalin-fixed paraffin-embedded medulloblastoma samples. Biomarkers were identified applying stringent selection filters and Linear Discriminant Analysis (LDA) method, and validated using DNA methylation microarray data, bisulfite pyrosequencing, and direct-bisulfite sequencing.Results: Using a LDA-based approach, we developed and validated a prediction method (EpiWNT-SHH classifier) based on six epigenetic biomarkers that allowed for rapid classification of medulloblastoma into the clinically relevant subgroups WNT, SHH, and non-WNT/non-SHH with excellent concordance (>99%) with current gold-standard methods, DNA methylation microarray, and gene signature profiling analysis. The EpiWNT-SHH classifier showed high prediction capacity using both frozen and formalin-fixed material, as well as diverse DNA methylation detection methods. Similarly, we developed a classifier specific for group 3 and group 4 tumors, based on five biomarkers (EpiG3-G4) with good discriminatory capacity, allowing for correct assignment of more than 92% of tumors. EpiWNT-SHH and EpiG3-G4 methylation profiles remained stable across tumor primary, metastasis, and relapse samples.Conclusions: The EpiWNT-SHH and EpiG3-G4 classifiers represent a new simplified approach for accurate, rapid, and cost-effective molecular classification of single medulloblastoma DNA samples, using clinically applicable DNA methylation detection methods. Clin Cancer Res; 24(6); 1355-63. ©2018 AACR.


Assuntos
Biomarcadores Tumorais , Neoplasias Cerebelares/diagnóstico , Neoplasias Cerebelares/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Meduloblastoma/diagnóstico , Meduloblastoma/genética , Biópsia , Ilhas de CpG , Metilação de DNA , Epigênese Genética , Epigenômica/métodos , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Reprodutibilidade dos Testes
19.
Nature ; 553(7686): 101-105, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29258295

RESUMO

Genomic sequencing has driven precision-based oncology therapy; however, the genetic drivers of many malignancies remain unknown or non-targetable, so alternative approaches to the identification of therapeutic leads are necessary. Ependymomas are chemotherapy-resistant brain tumours, which, despite genomic sequencing, lack effective molecular targets. Intracranial ependymomas are segregated on the basis of anatomical location (supratentorial region or posterior fossa) and further divided into distinct molecular subgroups that reflect differences in the age of onset, gender predominance and response to therapy. The most common and aggressive subgroup, posterior fossa ependymoma group A (PF-EPN-A), occurs in young children and appears to lack recurrent somatic mutations. Conversely, posterior fossa ependymoma group B (PF-EPN-B) tumours display frequent large-scale copy number gains and losses but have favourable clinical outcomes. More than 70% of supratentorial ependymomas are defined by highly recurrent gene fusions in the NF-κB subunit gene RELA (ST-EPN-RELA), and a smaller number involve fusion of the gene encoding the transcriptional activator YAP1 (ST-EPN-YAP1). Subependymomas, a distinct histologic variant, can also be found within the supratetorial and posterior fossa compartments, and account for the majority of tumours in the molecular subgroups ST-EPN-SE and PF-EPN-SE. Here we describe mapping of active chromatin landscapes in 42 primary ependymomas in two non-overlapping primary ependymoma cohorts, with the goal of identifying essential super-enhancer-associated genes on which tumour cells depend. Enhancer regions revealed putative oncogenes, molecular targets and pathways; inhibition of these targets with small molecule inhibitors or short hairpin RNA diminished the proliferation of patient-derived neurospheres and increased survival in mouse models of ependymomas. Through profiling of transcriptional enhancers, our study provides a framework for target and drug discovery in other cancers that lack known genetic drivers and are therefore difficult to treat.


Assuntos
Elementos Facilitadores Genéticos/genética , Ependimoma/tratamento farmacológico , Ependimoma/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes/genética , Terapia de Alvo Molecular , Oncogenes/genética , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Ependimoma/classificação , Ependimoma/patologia , Feminino , Humanos , Camundongos , Medicina de Precisão , Interferência de RNA , Ensaios Antitumorais Modelo de Xenoenxerto
20.
J Exp Med ; 215(1): 141-157, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29203539

RESUMO

The median overall survival for children with diffuse intrinsic pontine glioma (DIPG) is less than one year. The majority of diffuse midline gliomas, including more than 70% of DIPGs, harbor an amino acid substitution from lysine (K) to methionine (M) at position 27 of histone 3 variant 3 (H3.3). From a CD8+ T cell clone established by stimulation of HLA-A2+ CD8+ T cells with synthetic peptide encompassing the H3.3K27M mutation, complementary DNA for T cell receptor (TCR) α- and ß-chains were cloned into a retroviral vector. TCR-transduced HLA-A2+ T cells efficiently killed HLA-A2+H3.3K27M+ glioma cells in an antigen- and HLA-specific manner. Adoptive transfer of TCR-transduced T cells significantly suppressed the progression of glioma xenografts in mice. Alanine-scanning assays suggested the absence of known human proteins sharing the key amino acid residues required for recognition by the TCR, suggesting that the TCR could be safely used in patients. These data provide us with a strong basis for developing T cell-based therapy targeting this shared neoepitope.


Assuntos
Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Glioma/genética , Glioma/imunologia , Histonas/genética , Histonas/imunologia , Mutação , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transferência Adotiva , Sequência de Aminoácidos , Aminoácidos , Animais , Apresentação do Antígeno , Antígenos de Neoplasias/química , Cromatografia Líquida , Modelos Animais de Doenças , Mapeamento de Epitopos , Feminino , Glioma/patologia , Glioma/terapia , Antígenos HLA-A/imunologia , Antígenos HLA-A/metabolismo , Histonas/química , Humanos , Imunoterapia Adotiva , Camundongos , Camundongos Transgênicos , Peptídeos/química , Peptídeos/imunologia , Peptídeos/metabolismo , Ligação Proteica , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Espectrometria de Massas em Tandem , Ensaios Antitumorais Modelo de Xenoenxerto
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