Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Commun Biol ; 3(1): 450, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807853

RESUMO

Under hypoxic conditions, nitroimidazoles can replace oxygen as electron acceptors, thereby enhancing the effects of radiation on malignant cells. These compounds also accumulate in hypoxic cells, where they can act as cytotoxins or imaging agents. However, whether these effects apply to cancer stem cells has not been sufficiently explored. Here we show that the 2-nitroimidazole doranidazole potentiates radiation-induced DNA damage in hypoxic glioma stem cells (GSCs) and confers a significant survival benefit in mice harboring GSC-derived tumors in radiotherapy settings. Furthermore, doranidazole and misonidazole, but not metronidazole, manifested radiation-independent cytotoxicity for hypoxic GSCs that was mediated by ferroptosis induced partially through blockade of mitochondrial complexes I and II and resultant metabolic alterations in oxidative stress responses. Doranidazole also limited the growth of GSC-derived subcutaneous tumors and that of tumors in orthotopic brain slices. Our results thus reveal the theranostic potential of 2-nitroimidazoles as ferroptosis inducers that enable targeting GSCs in their hypoxic niche.

2.
Keio J Med ; 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32741855

RESUMO

Imidazole antifungal compounds exert their antipathogenic effects through inhibition of sterol biosynthesis. These drugs have also recently been identified as candidate anticancer agents for several solid tumors including glioblastoma. However, their effects on glioma-initiating cells (GICs), i.e., glioma cells with stemlike properties that are able to initiate tumors, remain unclear. Consequently, we examined the effects of the optically active imidazole compound luliconazole on mouse GICs and GIC-based tumors. Luliconazole impaired in a concentration-dependent manner the growth of spheres formed by GICs in vitro. In contrast to the inhibitory effects of ionizing radiation and temozolomide on sphere growth, that of luliconazole was attenuated by the addition of exogenous cholesterol. Exposure to luliconazole of brain slices derived from mice with orthotopic GIC implants for 4 days in culture resulted in a marked increase in the number of tumor cells positive for cleaved caspase-3, but without a similar effect on normal cells. Furthermore, in brain slices, luliconazole inhibited the expansion of GIC-based tumors and the parenchymal infiltration of tumor cells. Our findings therefore indicate that luliconazole effectively targets GICs, thereby providing further support for the antitumorigenic effects of imidazole antifungal compounds.

3.
Sci Rep ; 10(1): 6084, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32242056

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

4.
Mol Pharm ; 17(6): 1835-1847, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32315193

RESUMO

Inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase of the family of statins have been suggested as therapeutic options in various tumors. Atorvastatin is a statin with the potential to cross the blood-brain barrier; however, the concentrations necessary for a cytotoxic effect against cancer cells exceed the concentrations achievable via oral administration, which made the development of a novel atorvastatin formulation necessary. We characterized the drug loading and basic physicochemical characteristics of micellar atorvastatin formulations and tested their cytotoxicity against a panel of different glioblastoma cell lines. In addition, activity against tumor spheroids formed from mouse glioma and mouse cancer stem cells, respectively, was evaluated. Our results show good activity of atorvastatin against all tested cell lines. Interestingly, in the three-dimensional (3D) models, growth inhibition was more pronounced for the micellar formulation compared to free atorvastatin. Finally, atorvastatin penetration across a blood-brain barrier model obtained from human induced-pluripotent stem cells was evaluated. Our results suggest that the presented micelles may enable much higher serum concentrations than possible by oral administration; however, if transport across the blood-brain barrier is sufficient to reach the therapeutic atorvastatin concentration for the treatment of glioblastoma via intravenous administration remains unclear.

5.
Hum Gene Ther ; 31(5-6): 352-366, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32075424

RESUMO

Glioblastoma is the most aggressive brain tumor characterized by diffuse infiltration into the normal brain parenchyma. Neural stem cells are known to possess the tumor-tropic migratory capacity and thus can be used as cellular vehicles for targeted delivery of therapeutic agents. In the present study, we evaluated the efficacy of herpes simplex virus thymidine kinase (HSV-TK) suicide gene therapy for glioblastoma using neural stem/progenitor cells (NS/PCs) derived from human induced pluripotent stem cells (hiPSCs). Although transduction of hiPSCs is preferable for a safe and stable supply in the clinical setting, high-level and/or constitutive HSV-TK expression was highly cytotoxic to hiPSCs. To overcome this problem, we used the tetracycline-inducible system to control the expression of HSV-TK. hiPSC-derived NS/PCs expressing HSV-TK were transplanted in an orthotopic xenograft mouse model of human glioblastoma. Glioblastoma cell growth in mice was dramatically inhibited following ganciclovir (GCV) administration. Survival of the mice was significantly prolonged with administration of GCV compared with control groups. Time-lapse imaging of organotypic brain slice cultures first demonstrated the directional migration of NS/PCs toward glioblastoma cells and the bystander killing effect upon GCV treatment. hiPSC-derived NS/PCs with HSV-TK/GCV suicide gene system may have considerable therapeutic potential for the treatment of glioblastoma. Color images are available online.

6.
Mol Cancer Ther ; 19(2): 375-383, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31727689

RESUMO

Gliomas are the second most common primary brain tumors in adults. They are treated with combination therapies, including surgery, radiotherapy, and chemotherapy. There are currently limited treatment options for recurrent gliomas, and new targeted therapies need to be identified, especially in glioblastomas, which have poor prognosis. Isocitrate dehydrogenase (IDH) mutations are detected in various tumors, including gliomas. Most patients with IDH mutant glioma harbor the IDH1R132H subtype. Mutant IDH catalyzes the conversion of α-ketoglutarate to the oncometabolite 2-hydroxyglutarate (2-HG), which induces aberrant epigenetic status and contributes to malignant progression, and is therefore a potential therapeutic target for IDH mutant tumors. The present study describes a novel, orally bioavailable selective mutant IDH1 inhibitor, DS-1001b. The drug has high blood-brain barrier (BBB) permeability and inhibits IDH1R132H. Continuous administration of DS-1001b impaired tumor growth and decreased 2-HG levels in subcutaneous and intracranial xenograft models derived from a patient with glioblastoma with IDH1 mutation. Moreover, the expression of glial fibrillary acidic protein was strongly induced by DS-1001b, suggesting that inhibition of mutant IDH1 promotes glial differentiation. These results reveal the efficacy of BBB-permeable DS-1001b in orthotopic patient-derived xenograft models and provide a preclinical rationale for the clinical testing of DS-1001b in recurrent gliomas.

7.
Nat Cell Biol ; 21(8): 1003-1014, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31371825

RESUMO

In many cancers, high proliferation rates correlate with elevation of rRNA and tRNA levels, and nucleolar hypertrophy. However, the underlying mechanisms linking increased nucleolar transcription and tumorigenesis are only minimally understood. Here we show that IMP dehydrogenase-2 (IMPDH2), the rate-limiting enzyme for de novo guanine nucleotide biosynthesis, is overexpressed in the highly lethal brain cancer glioblastoma. This leads to increased rRNA and tRNA synthesis, stabilization of the nucleolar GTP-binding protein nucleostemin, and enlarged, malformed nucleoli. Pharmacological or genetic inactivation of IMPDH2 in glioblastoma reverses these effects and inhibits cell proliferation, whereas untransformed glia cells are unaffected by similar IMPDH2 perturbations. Impairment of IMPDH2 activity triggers nucleolar stress and growth arrest of glioblastoma cells even in the absence of functional p53. Our results reveal that upregulation of IMPDH2 is a prerequisite for the occurance of aberrant nucleolar function and increased anabolic processes in glioblastoma, which constitutes a primary event in gliomagenesis.


Assuntos
Carcinogênese/metabolismo , Glioblastoma/metabolismo , IMP Desidrogenase/metabolismo , Linhagem Celular Tumoral , Nucléolo Celular/metabolismo , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/metabolismo , Humanos , IMP Desidrogenase/genética , RNA Ribossômico/metabolismo
8.
Mol Brain ; 12(1): 45, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-31060588

RESUMO

Glioblastoma exhibits phenotypic and genetic heterogeneity, aggressive invasiveness, therapeutic resistance, and tumor recurrence, which can be explained by the existence of glioma stem cells (GSCs). In this study, we visualized the spatiotemporal dynamics of invasion of human GSCs in an orthotopic xenograft mouse model using time-lapse imaging of organotypic brain slice cultures and three-dimensional imaging of optically cleared whole brains. GSCs implanted in the striatum exhibited directional migration toward axon bundles, perivascular area, and the subventricular zone around the inferior horn of the lateral ventricle. GSCs migrated in a helical pattern around axon bundles in the striatum and invaded broadly in both the rostral and caudal directions. GSCs in the corpus callosum migrated more rapidly and unidirectionally toward the contralateral side with pseudopod extension. These characteristics of GSC invasion shared histological features observed in glioblastoma patients. Spatiotemporal visualization techniques can contribute to the elucidation of the mechanisms underlying GSC invasion that may lead to the development of effective therapy for glioblastoma.

9.
Cancer Sci ; 109(12): 3874-3882, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30298963

RESUMO

Autocrine and paracrine factors, including glutamate and epidermal growth factor (EGF), are potent inducers of brain tumor cell invasion, a pathological hallmark of malignant gliomas. System xc(-) consists of xCT and CD98hc subunits and functions as a plasma membrane antiporter for the uptake of extracellular cystine in exchange for intracellular glutamate. We previously showed that the EGF receptor (EGFR) interacts with xCT and thereby promotes the activity of system xc(-) in a kinase-independent manner, resulting in enhanced glutamate release in glioma cells. However, the molecular mechanism underlying EGFR-mediated glioma progression in a glutamate-rich microenvironment has remained unclear. Here we show that the GluN2B subunit of the N-methyl-d-aspartate-sensitive glutamate receptor (NMDAR) is a substrate of EGFR in glioma cells. In response to EGF stimulation, EGFR phosphorylated the COOH-terminal domain of GluN2B and thereby enhanced glutamate-NMDAR signaling and consequent cell migration in EGFR-overexpressing glioma cells. Treatment with the NMDAR inhibitor MK-801 or the system xc(-) inhibitor sulfasalazine suppressed EGF-elicited glioma cell migration. The administration of sulfasalazine and MK-801 also synergistically suppressed the growth of subcutaneous tumors formed by EGFR-overexpressing glioma cells. Furthermore, shRNA-mediated knockdown of xCT and GluN2B cooperatively prolonged the survival of mice injected intracerebrally with such glioma cells. Our findings thus establish a central role for EGFR in the signaling crosstalk between xCT and GluN2B-containing NMDAR in glioma cells.


Assuntos
Sistema y+ de Transporte de Aminoácidos/metabolismo , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Progressão da Doença , Maleato de Dizocilpina/administração & dosagem , Maleato de Dizocilpina/farmacologia , Sinergismo Farmacológico , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Glioma/tratamento farmacológico , Ácido Glutâmico/metabolismo , Humanos , Camundongos , Transplante de Neoplasias , Fosforilação , Domínios Proteicos , Receptores de N-Metil-D-Aspartato/química , Transdução de Sinais/efeitos dos fármacos , Sulfassalazina/administração & dosagem , Sulfassalazina/farmacologia
10.
Int J Mol Sci ; 19(8)2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30042341

RESUMO

Intratumoral human epidermal growth factor receptor 2 (HER2) heterogeneity has been reported in 16⁻36% of HER2-positive breast cancer and its clinical impact is under discussion. We examined the biological effects of HER2-heterogeneity on mouse models and analyzed metastatic brains by RNA sequence analysis. A metastatic mouse model was developed using 231-Luc (triple negative cells) and 2 HER2-positive cell lines, namely, HER2-60 and HER2-90 which showed heterogeneous and monotonous HER2 expressions, respectively. Metastatic lesions developed in 3 weeks in all the mice injected with HER2-60 cells, and in 69% of the mice injected with HER2-90 and 87.5% of the mice injected with 231-Luc. The median survival days of mice injected with 231-Luc, HER2-60, and HER2-90 cells were 29 (n = 24), 24 (n = 22) and 30 (n = 13) days, respectively. RNA sequence analysis showed that CASP-1 and its related genes were significantly downregulated in metastatic brain tumors with HER2-60 cells. The low expression of caspase-1 could be a new prognostic biomarker for early relapse in HER2-positive breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Heterogeneidade Genética , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Caspase 1/genética , Caspase 1/metabolismo , Feminino , Humanos , Estimativa de Kaplan-Meier , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Prognóstico , Recidiva , Análise de Sequência de RNA
11.
Sci Rep ; 8(1): 6069, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29666462

RESUMO

Neurofibromatosis type 1 (NF1) is caused by germline mutations in the NF1 gene and is characterized by café au lait spots and benign tumours known as neurofibromas. NF1 encodes the tumour suppressor protein neurofibromin, which negatively regulates the small GTPase Ras, with the constitutive activation of Ras signalling resulting from NF1 mutations being thought to underlie neurofibroma development. We previously showed that knockdown of neurofibromin triggers epithelial-mesenchymal transition (EMT) signalling and that such signalling is activated in NF1-associated neurofibromas. With the use of a cell-based drug screening assay, we have now identified the antiallergy drug tranilast (N-(3,4-dimethoxycinnamoyl) anthranilic acid) as an inhibitor of EMT and found that it attenuated the expression of mesenchymal markers and angiogenesis-related genes in NF1-mutated sNF96.2 cells and in neurofibroma cells from NF1 patients. Tranilast also suppressed the proliferation of neurofibromin-deficient cells in vitro more effectively than it did that of intact cells. In addition, tranilast inhibited sNF96.2 cell migration and proliferation in vivo. Knockdown of type III collagen (COL3A1) also suppressed the proliferation of neurofibroma cells, whereas expression of COL3A1 and SOX2 was increased in tranilast-resistant cells, suggesting that COL3A1 and the transcription factor SOX2 might contribute to the development of tranilast resistance.


Assuntos
Antialérgicos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Neurofibromina 1/genética , ortoaminobenzoatos/farmacologia , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Feminino , Deleção de Genes , Genes da Neurofibromatose 1/efeitos dos fármacos , Mutação em Linhagem Germinativa , Células HeLa , Humanos , Camundongos SCID , Invasividade Neoplásica/genética , Invasividade Neoplásica/prevenção & controle , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neurofibromatose 1/tratamento farmacológico , Neurofibromatose 1/genética
12.
Nat Commun ; 9(1): 1561, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29674746

RESUMO

Gold deposition with diagonal angle towards boehmite-based nanostructure creates random arrays of horse-bean-shaped nanostructures named gold-nanofève (GNF). GNF generates many electromagnetic hotspots as surface-enhanced Raman spectroscopy (SERS) excitation sources, and enables large-area visualization of molecular vibration fingerprints of metabolites in human cancer xenografts in livers of immunodeficient mice with sufficient sensitivity and uniformity. Differential screening of GNF-SERS signals in tumours and those in parenchyma demarcated tumour boundaries in liver tissues. Furthermore, GNF-SERS combined with quantum chemical calculation identified cysteine-derived glutathione and hypotaurine (HT) as tumour-dominant and parenchyma-dominant metabolites, respectively. CD44 knockdown in cancer diminished glutathione, but not HT in tumours. Mechanisms whereby tumours sustained HT under CD44-knockdown conditions include upregulation of PHGDH, PSAT1 and PSPH that drove glycolysis-dependent activation of serine/glycine-cleavage systems to provide one-methyl group for HT synthesis. HT was rapidly converted into taurine in cancer cells, suggesting that HT is a robust anti-oxidant for their survival under glutathione-suppressed conditions.


Assuntos
Antioxidantes/química , Antioxidantes/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Neoplasias/metabolismo , Análise Espectral Raman/métodos , Taurina/análogos & derivados , Animais , Feminino , Glutationa/metabolismo , Ouro/metabolismo , Humanos , Fígado/química , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Neoplasias/genética , Análise Espectral Raman/instrumentação , Taurina/química , Taurina/metabolismo , Transaminases/genética , Transaminases/metabolismo
13.
Sci Rep ; 8(1): 2785, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29434323

RESUMO

CD44 variant (CD44v) contributes to cancer stemness by stabilizing the xCT subunit of system xc(-) and thereby promoting its glutamate-cystine antiporter activity. CD44 has also been implicated in autoimmune insulitis and inflammation in diabetic islets, but whether CD44v regulates insulin secretion has remained unclear. Here we show that CD44v inhibits insulin secretion by attenuating amino acid transport mediated by the L-type amino acid transporter LAT1. CD44v expression level was inversely related to insulin content in islets of normal and diabetic model mice. Knockdown of CD44 increased insulin secretion, the intracellular insulin level, and the transport of neutral amino acids mediated by LAT1 in Min6 cells. Attenuation of the uptake of neutral amino acids with a LAT inhibitor reduced insulin secretion and insulin content in Min6 cells, whereas overexpression of LAT1 increased insulin secretion. Moreover, inhibition of LAT1 prevented the increase in insulin secretion and content induced by CD44 depletion in Min6 cells. Our results thus implicate CD44v in the regulation of insulin secretion and reveal that amino acid transport is rate limiting for such secretion. They further suggest that amino acid transport mediated by LAT1 is a potential therapeutic target for diabetes.


Assuntos
Sistema y+ de Transporte de Aminoácidos/metabolismo , Receptores de Hialuronatos/metabolismo , Secreção de Insulina/fisiologia , Células Secretoras de Insulina/efeitos dos fármacos , Sistema y+ de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/fisiologia , Animais , Linhagem Celular , Proliferação de Células/fisiologia , Cistina/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Receptores de Hialuronatos/genética , Células Secretoras de Insulina/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
14.
Cancer Sci ; 109(1): 6-14, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28796931

RESUMO

Malignant gliomas are primary tumors of the central nervous system characterized by diffuse infiltration into the brain and a high recurrence rate. Advances in comprehensive genomic studies have provided unprecedented insight into the genetic and molecular heterogeneity of these tumors and refined our understanding of their evolution from low to high grade. However, similar levels of phenotypic characterization are indispensable to understanding the complexity of malignant gliomas. Experimental glioma models have also achieved great progress in recent years. Advances in transgenic technologies and cell culture have allowed the establishment of mouse models that mirror the human disease with increasing fidelity and which support single-cell resolution for phenotypic analyses. Here we review the major types of preclinical glioma models, with an emphasis on how recent developments in experimental modeling have shed new light on two fundamental aspects of glioma phenotype, their cell of origin and their invasive potential.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Animais , Humanos , Camundongos , Camundongos Transgênicos , Invasividade Neoplásica , Transplante de Neoplasias , Análise de Célula Única
15.
Neuro Oncol ; 20(3): 343-354, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-29016888

RESUMO

Background: Glioblastomas have been shown to rely on glycolysis as an energy source. However, recent evidence suggests that at least a subset of glioma cells with stem cell-like properties can thrive on oxidative phosphorylation. It remains unclear whether both metabolic phenotypes support tumor propagation, if they are independent, and how stable they are. The present study investigated these questions with the use of isogenic murine glioma stem cells (GSCs). Methods: GSCs were established from tumors formed by Ink4a/Arf-null, H-RasV12-expressing glioma-initiating cells that differed in extracellular acidification potential. Metabolic characteristics of GSCs were determined by measurement of glucose, oxygen, and glutamine uptake, ATP content, and lactate production. Effects of metabolic inhibitors and changes in oxygen or nutrient availability on lactate production and tumorsphere growth were also determined. Results: GSCs were found either to consume more glucose and produce more lactate or to consume more oxygen and maintain a higher ATP content depending on the metabolic characteristics of the tumor cells of origin. The latter, mitochondrial-type GSCs increased lactate production after treatment with the oxidative phosphorylation inhibitor oligomycin or phenformin. Exposure to hypoxia also increased lactate production and expression of glycolysis-related enzymes and metabolites in mitochondrial-type GSCs in a reversible manner. Conclusions: Both glycolytic and mitochondrial-type energy production can sustain tumor propagation by isogenic GSCs. Whereas both phenotypes can be independent and stable, cells that rely on oxidative phosphorylation can also switch to a more glycolytic phenotype in response to metabolic stress, suggesting that plasticity is a further characteristic of GSC metabolism.


Assuntos
Neoplasias Encefálicas/metabolismo , Modelos Animais de Doenças , Glioblastoma/metabolismo , Metaboloma , Mitocôndrias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Neoplasias Encefálicas/patologia , Feminino , Glioblastoma/patologia , Glucose/metabolismo , Glicólise , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/patologia , Células-Tronco Neoplásicas/patologia , Fosforilação Oxidativa , Células Tumorais Cultivadas
16.
J Neurooncol ; 136(1): 23-31, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28929335

RESUMO

Expression of CD44 in glioma cells was previously correlated with tumor grade and is considered a stem cell marker. CD44 stabilizes the cystine-glutamate transporter (xCT) and inhibits apoptosis in cancer stem cells (CSCs). Recently it was found that Sulfasalazine (SSZ), an anti-inflammatory drug, acts as an inhibitor of xCT and therefore has potential as a targeted therapy for CSCs. In this study, we tested an efficacy of SSZ against glioma stem cell model developed in rats. As poor penetration of blood-brain barrier resulted in insufficient efficacy of systemic SSZ treatment, SSZ was delivered locally with convection-enhanced delivery (CED). In vitro, expression of CD44 in glioma cells and efficacy of SSZ against glioma cells and glioma stem cells were confirmed. SSZ demonstrated anti-proliferative activity in a dose dependent manner against these cells. This activity was partially reversible with the addition of antioxidant, N-acetyl-L-cysteine, to the medium. In vivo, CED successfully delivered SSZ into the rat brain parenchyma. When delivered at 5 mM concentration, which was the highest possible concentration when SSZ was dissolved in water, CED of SSZ resulted in almost no tissue damage. Against highly malignant bRiTs-G3 brain tumor xenografted rat model; the glioma stem cell model, CED of SSZ at 5 mM concentration induced apoptosis and prolonged survival. Consequently, CED of SSZ induced glioma stem cell death without evidence of tissue damage to normal brain parenchyma. This strategy may be a promising targeted treatment against glioma stem cells.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Sulfassalazina/administração & dosagem , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Apoptose/efeitos dos fármacos , Química Encefálica , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Convecção , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Glioma/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Masculino , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Ratos , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Nat Commun ; 8(1): 2200, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29259156

RESUMO

Achieving robust cancer-specific lethality is the ultimate clinical goal. Here, we identify a compound with dual-inhibitory properties, named a131, that selectively kills cancer cells, while protecting normal cells. Through an unbiased CETSA screen, we identify the PIP4K lipid kinases as the target of a131. Ablation of the PIP4Ks generates a phenocopy of the pharmacological effects of PIP4K inhibition by a131. Notably, PIP4Ks inhibition by a131 causes reversible growth arrest in normal cells by transcriptionally upregulating PIK3IP1, a suppressor of the PI3K/Akt/mTOR pathway. Strikingly, Ras activation overrides a131-induced PIK3IP1 upregulation and activates the PI3K/Akt/mTOR pathway. Consequently, Ras-transformed cells override a131-induced growth arrest and enter mitosis where a131's ability to de-cluster supernumerary centrosomes in cancer cells eliminates Ras-activated cells through mitotic catastrophe. Our discovery of drugs with a dual-inhibitory mechanism provides a unique pharmacological strategy against cancer and evidence of cross-activation between the Ras/Raf/MEK/ERK and PI3K/AKT/mTOR pathways via a Ras˧PIK3IP1˧PI3K signaling network.


Assuntos
Acrilonitrila/análogos & derivados , Indóis/farmacologia , Isoquinolinas/farmacologia , Proteínas de Membrana/metabolismo , Mitose/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Acrilonitrila/farmacologia , Acrilonitrila/uso terapêutico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Indóis/uso terapêutico , Isoquinolinas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Inibidores de Proteínas Quinases/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas ras/metabolismo
18.
Cancer Med ; 6(11): 2635-2645, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28980419

RESUMO

Therapeutic options for malignant brain tumors are limited, with new drugs being continuously evaluated. Organotypic brain slice culture has been adopted for neuroscience studies as a system that preserves brain architecture, cellular function, and the vascular network. However, the suitability of brain explants for anticancer drug evaluation has been unclear. We here adopted a mouse model of malignant glioma based on expression of H-RasV12 in Ink4a/Arf-/- neural stem/progenitor cells to establish tumor-bearing brain explants from adult mice. We treated the slices with cisplatin, temozolomide, paclitaxel, or tranilast and investigated the minimal assays required to assess drug effects. Serial fluorescence-based tumor imaging was sufficient for evaluation of cisplatin, a drug with a pronounced cytotoxic action, whereas immunostaining of cleaved caspase 3 (a marker of apoptosis) and of Ki67 (a marker of cell proliferation) was necessary for the assessment of temozolomide action and immunostaining for phosphorylated histone H3 (a marker of mitosis) allowed visualization of paclitaxel-specific effects. Staining for cleaved caspase 3 was also informative in the assessment of drug toxicity for normal brain tissue. Incubation of explants with fluorescently labeled antibodies to CD31 allowed real-time imaging of the microvascular network and complemented time-lapse imaging of tumor cell invasion into surrounding tissue. Our results suggest that a combination of fluorescence imaging and immunohistological staining allows a unified assessment of the effects of various classes of drug on the survival, proliferation, and invasion of glioma cells, and that organotypic brain slice culture is therefore a useful tool for evaluation of antiglioma drugs.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Glioma/tratamento farmacológico , Técnicas de Cultura de Tecidos , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Neoplasias Encefálicas/patologia , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Modelos Animais de Doenças , Imunofluorescência , Genes ras , Glioma/patologia , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Camundongos , Microscopia Confocal , Invasividade Neoplásica , Células-Tronco Neurais , Paclitaxel/farmacologia , Esferoides Celulares/efeitos dos fármacos , Temozolomida , ortoaminobenzoatos/farmacologia
19.
Integr Biol (Camb) ; 9(9): 762-773, 2017 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-28752870

RESUMO

Glioblastoma (GBM) is a highly invasive primary brain tumor that displays cellular heterogeneity, which is composed of glioma initiating cells (GICs) and their differentiated progeny. GICs play an important role in driving aggressive invasion. In particular, the interaction between GICs and blood vessels is critical because blood vessels are known to serve as routes for the invasion of GICs. However, the effect of endothelial cells on the three-dimensional (3D) invasion process of GICs as well as the spatial relationship between GICs and their differentiated progeny remains unclear. Here, we utilized a microfluidic device to recapitulate the 3D brain tumor microenvironments constituted by human umbilical vein endothelial cells (HUVECs) and type I collagen. Using the device, we found that HUVECs promoted the 3D invasion of heterogeneous glioma cell populations into type I collagen gel. The invasion induced by HUVECs was predominantly preceded by cells positive for nestin, a neural stem cell marker. In contrast, cells positive for tubulin ß3 (TUBB3), a differentiated cell marker, rarely preceded invasion. In addition, HUVECs induced the upregulation of TUBB3 in GICs. Finally, we found that the genes associated with invasion, such as integrins α2 and ß3, were significantly upregulated in the presence of HUVECs. These results as well as the experimental approach provide valuable knowledge for the development of effective therapeutic strategies targeting the aggressive invasion of GBM.


Assuntos
Neoplasias Encefálicas/patologia , Glioma/patologia , Animais , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/genética , Diferenciação Celular , Linhagem Celular Tumoral , Técnicas de Cocultura , Colágeno Tipo I/metabolismo , Glioblastoma/irrigação sanguínea , Glioblastoma/genética , Glioblastoma/patologia , Glioma/irrigação sanguínea , Glioma/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Integrinas/genética , Dispositivos Lab-On-A-Chip , Camundongos , Modelos Biológicos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Células-Tronco Neoplásicas/patologia , Células-Tronco Neurais/patologia , Regulação para Cima
20.
J Neurooncol ; 133(2): 297-307, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28555424

RESUMO

DEP domain containing 1 (DEPDC1) is a novel oncoantigen expressed in cancer cells, which presents oncogenic activity and high immunogenicity. Although DEPDC1 has been predicted to be a useful antigen for the development of a cancer vaccine, its pathophysiological roles in glioma have not been investigated. Here, we analyzed the expression and function of DEPDC1 in malignant glioma. DEPDC1 expression in glioma cell lines, glioma tissues, and brain tumor initiating cells (BTICs) was assessed by western blot and quantitative polymerase chain reaction (PCR). The effect of DEPDC1 downregulation on cell growth and nuclear factor kappa B (NFκB) signaling in glioma cells was investigated. Overall survival was assessed in mouse glioma models using human glioma cells and induced mouse brain tumor stem cells (imBTSCs) to determine the effect of DEPDC1 suppression in vivo. DEPDC1 expression was increased in glioma cell lines, tissues, and BTICs. Suppression of endogenous DEPDC1 expression by small interfering RNA (siRNA) inhibited glioma cell viability and induced apoptosis through NFκB signaling. In mouse glioma models using human glioma cells and imBTSCs, downregulation of DEPDC1 expression prolonged overall survival. These results suggest that DEPDC1 represents a target molecule for the treatment of glioma.


Assuntos
Neoplasias Encefálicas/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Glioma/metabolismo , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/fisiologia , Feminino , Proteínas Ativadoras de GTPase/genética , Glioma/patologia , Humanos , Masculino , Camundongos , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/patologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA