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1.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38474302

RESUMO

Our previous research studies have demonstrated the role of microRNA133b (miR133b) in healing the contused spinal cord when administered either intranasally or intravenously 24 h following an injury. While our data showed beneficial effects of exogenous miR133b delivered within hours of a spinal cord injury (SCI), the kinetics of endogenous miR133b levels in the contused spinal cord and rostral/caudal segments of the injury were not fully investigated. In this study, we examined the miR133b dysregulation in a mouse model of moderate unilateral contusion injury at the fifth cervical (C5) level. Between 30 min and 7 days post-injury, mice were euthanized and tissues were collected from different areas of the spinal cord, ipsilateral and contralateral prefrontal motor cortices, and off-targets such as lung and spleen. The endogenous level of miR133b was determined by RT-qPCR. We found that after SCI, (a) most changes in miR133b level were restricted to the injured area with very limited alterations in the rostral and caudal parts relative to the injury site, (b) acute changes in the endogenous levels were predominantly specific to the lesion site with delayed miR133b changes in the motor cortex, and (c) ipsilateral and contralateral hemispheres responded differently to unilateral SCI. Our results suggest that the therapeutic window for exogenous miR133b therapy begins earlier than 24 h post-injury and potentially lasts longer than 7 days.


Assuntos
Medula Cervical , Contusões , MicroRNAs , Traumatismos da Medula Espinal , Animais , Camundongos , Contusões/metabolismo , Modelos Animais de Doenças , MicroRNAs/metabolismo , MicroRNAs/uso terapêutico , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/terapia , Medula Cervical/lesões
2.
Circ Res ; 127(9): e210-e231, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32755283

RESUMO

RATIONALE: Brain arteriovenous malformations (AVMs) are abnormal tangles of vessels where arteries and veins directly connect without intervening capillary nets, increasing the risk of intracerebral hemorrhage and stroke. Current treatments are highly invasive and often not feasible. Thus, effective noninvasive treatments are needed. We previously showed that AVM-brain endothelial cells (BECs) secreted higher VEGF (vascular endothelial growth factor) and lower TSP-1 (thrombospondin-1) levels than control BEC; and that microRNA-18a (miR-18a) normalized AVM-BEC function and phenotype, although its mechanism remained unclear. OBJECTIVE: To elucidate the mechanism of action and potential clinical application of miR-18a as an effective noninvasive treatment to selectively restore the phenotype and functionality of AVM vasculature. METHODS AND RESULTS: The molecular pathways affected by miR-18a in patient-derived BECs and AVM-BECs were determined by Western blot, RT-qPCR (quantitative reverse transcription polymerase chain reaction), ELISA, co-IP, immunostaining, knockdown and overexpression studies, flow cytometry, and luciferase reporter assays. miR-18a was shown to increase TSP-1 and decrease VEGF by reducing PAI-1 (plasminogen activator inhibitor-1/SERPINE1) levels. Furthermore, miR-18a decreased the expression of BMP4 (bone morphogenetic protein 4) and HIF-1α (hypoxia-inducible factor 1α), blocking the BMP4/ALK (activin-like kinase) 2/ALK1/ALK5 and Notch signaling pathways. As determined by Boyden chamber assays, miR-18a also reduced the abnormal AVM-BEC invasiveness, which correlated with a decrease in MMP2 (matrix metalloproteinase 2), MMP9, and ADAM10 (ADAM metallopeptidase domain 10) levels. In vivo pharmacokinetic studies showed that miR-18a reaches the brain following intravenous and intranasal administration. Intranasal co-delivery of miR-18a and NEO100, a good manufacturing practices-quality form of perillyl alcohol, improved the pharmacokinetic profile of miR-18a in the brain without affecting its pharmacological properties. Ultra-high-resolution computed tomography angiography and immunostaining studies in an Mgp-/- AVM mouse model showed that miR-18a decreased abnormal cerebral vasculature and restored the functionality of the bone marrow, lungs, spleen, and liver. CONCLUSIONS: miR-18a may have significant clinical value in preventing, reducing, and potentially reversing AVM.


Assuntos
Proteína Morfogenética Óssea 4/antagonistas & inibidores , Células Endoteliais/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Malformações Arteriovenosas Intracranianas/terapia , MicroRNAs/uso terapêutico , Trombospondina 1/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteína ADAM10/metabolismo , Receptores de Ativinas Tipo I/metabolismo , Receptores de Activinas Tipo II/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Humanos , Malformações Arteriovenosas Intracranianas/genética , Malformações Arteriovenosas Intracranianas/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Monoterpenos/administração & dosagem , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo
3.
Eur Spine J ; 31(7): 1775-1783, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35147769

RESUMO

PURPOSE: The aim of this study was to characterize if the use of surgical drains or length of drain placement following spine surgery increases the risk of post-operative infection. METHODS: Records of patients undergoing elective spinal surgery at a tertiary care center were collected between May 5, 2016 and August 16, 2018. Pre-operative baseline characteristics were recorded including patient's demographics and comorbidities. Intraoperative procedure information was documented related to procedure type, blood loss, and antibiotics used. Following surgery, patients were then further subdivided into two groups: patients who were discharged with a spinal surgical site drain and patients who did not receive a drain. Post-operative surgical variables included length of stay (LOS), drain length, number of antibiotics given, and type of post-operative infection. Univariate and multivariate statistical analysis was conducted. RESULTS: A total of 671 patients were included in the current study, 386 (57.5%) with and 285 (42.5%) without the drain. The overall infection rate was 5.7% with 6.22% among patients with the drain compared to 4.91% in patients without drain. The univariate analysis identified the following variables to be significantly associated with the infection: total number of surgical levels, spinal region, blood loss, redosing of antibiotics, length of stay, length of drain placement, and number of antibiotics (P < 0.05). However, the multivariate analysis none of the predictors was significant. CONCLUSIONS: The current study shows that the placement of drain does not increase rate of infection, irrespective of levels, length of surgery, or approach.


Assuntos
Drenagem , Infecção da Ferida Cirúrgica , Antibacterianos/uso terapêutico , Drenagem/efeitos adversos , Drenagem/métodos , Humanos , Tempo de Internação , Região Lombossacral , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia
4.
J Neurosci Res ; 99(9): 2029-2045, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33969526

RESUMO

CRISPR (clustered regularly interspaced short palindromic repeat)-based genetic screens offer unbiased and powerful tools for systematic and specific evaluation of phenotypes associated with specific target genes. CRISPR screens have been utilized heavily in vitro to identify functional coding and noncoding genes in a large number of cell types, including glioblastoma (GB), though no prior study has described the evaluation of CRISPR screening in GB in vivo. Here, we describe a protocol for targeting and transcriptionally repressing GB-specific long noncoding RNAs (lncRNAs) by CRISPR interference (CRISPRi) system in vivo, with tumor growth in the mouse cerebral cortex. Given the target-specific parameters of each individual screen, we list general steps involved in transducing guide RNA libraries into GB tumor lines, maintaining sufficient coverage, as well as cortically injecting and subsequently isolating transduced screen tumor cell populations for analysis. Finally, in order to demonstrate the use of this technique to discern an essential lncRNA, HOTAIR, from a nonessential lncRNA, we injected a 1:1 (HOTAIR:control nonessential lncRNA knockdown) mixture of fluorescently tagged U87 GB cells into the cortex of eight mice, evaluating selective depletion of HOTAIR-tagged cells at 2 weeks of growth. Fluorescently tagged populations were analyzed via flow cytometry for hiBFP (control knockdown) and green fluorescent protein (HOTAIR knockdown), revealing 17% (p = 0.007) decrease in fluorescence associated with HOTAIR knockdown relative to control. The described in vivo CRISPR screening methodology thus appears to be an effective option for identifying noncoding (and coding) genes affecting GB growth within the mouse cortex.


Assuntos
Neoplasias Encefálicas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Glioblastoma/genética , RNA não Traduzido/genética , Animais , Neoplasias Encefálicas/patologia , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Técnicas de Inativação de Genes/métodos , Glioblastoma/patologia , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Nus , Carga Tumoral/genética
5.
Nature ; 526(7571): 118-21, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26374997

RESUMO

Development of functional nanoparticles can be encumbered by unanticipated material properties and biological events, which can affect nanoparticle effectiveness in complex, physiologically relevant systems. Despite the advances in bottom-up nanoengineering and surface chemistry, reductionist functionalization approaches remain inadequate in replicating the complex interfaces present in nature and cannot avoid exposure of foreign materials. Here we report on the preparation of polymeric nanoparticles enclosed in the plasma membrane of human platelets, which are a unique population of cellular fragments that adhere to a variety of disease-relevant substrates. The resulting nanoparticles possess a right-side-out unilamellar membrane coating functionalized with immunomodulatory and adhesion antigens associated with platelets. Compared to uncoated particles, the platelet membrane-cloaked nanoparticles have reduced cellular uptake by macrophage-like cells and lack particle-induced complement activation in autologous human plasma. The cloaked nanoparticles also display platelet-mimicking properties such as selective adhesion to damaged human and rodent vasculatures as well as enhanced binding to platelet-adhering pathogens. In an experimental rat model of coronary restenosis and a mouse model of systemic bacterial infection, docetaxel and vancomycin, respectively, show enhanced therapeutic efficacy when delivered by the platelet-mimetic nanoparticles. The multifaceted biointerfacing enabled by the platelet membrane cloaking method provides a new approach in developing functional nanoparticles for disease-targeted delivery.


Assuntos
Antibacterianos/administração & dosagem , Plaquetas/citologia , Membrana Celular/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/administração & dosagem , Nanopartículas/química , Adesividade Plaquetária , Animais , Antibacterianos/farmacocinética , Vasos Sanguíneos/citologia , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Colágeno/química , Colágeno/imunologia , Ativação do Complemento/imunologia , Reestenose Coronária/sangue , Reestenose Coronária/tratamento farmacológico , Reestenose Coronária/metabolismo , Modelos Animais de Doenças , Docetaxel , Humanos , Macrófagos/imunologia , Masculino , Camundongos , Polímeros/química , Ratos , Ratos Sprague-Dawley , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/metabolismo , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/citologia , Staphylococcus aureus/metabolismo , Taxoides/administração & dosagem , Taxoides/farmacocinética , Lipossomas Unilamelares/química , Vancomicina/administração & dosagem , Vancomicina/farmacocinética
6.
Int J Mol Sci ; 21(4)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32093290

RESUMO

Prodrug activator gene therapy mediated by murine leukemia virus (MLV)-based retroviral replicating vectors (RRV) was previously shown to be highly effective in killing glioma cells both in culture and in vivo. To avoid receptor interference and enable dual vector co-infection with MLV-RRV, we have developed another RRV based on gibbon ape leukemia virus (GALV) that also shows robust replicative spread in a wide variety of tumor cells. We evaluated the potential of GALV-based RRV as a cancer therapeutic agent by incorporating yeast cytosine deaminase (CD) and E. coli nitroreductase (NTR) prodrug activator genes into the vector. The expression of CD and NTR genes from GALV-RRV achieved highly efficient delivery of these prodrug activator genes to RG-2 glioma cells, resulting in enhanced cytotoxicity after administering their respective prodrugs 5-fluorocytosine and CB1954 in vitro. In an immune-competent intracerebral RG-2 glioma model, GALV-mediated CD and NTR gene therapy both significantly suppressed tumor growth with CB1954 administration after a single injection of vector supernatant. However, NTR showed greater potency than CD, with control animals receiving GALV-NTR vector alone (i.e., without CB1954 prodrug) showing extensive tumor growth with a median survival time of 17.5 days, while animals receiving GALV-NTR and CB1954 showed significantly prolonged survival with a median survival time of 30 days. In conclusion, GALV-RRV enabled high-efficiency gene transfer and persistent expression of NTR, resulting in efficient cell killing, suppression of tumor growth, and prolonged survival upon CB1954 administration. This validates the use of therapeutic strategies employing this prodrug activator gene to arm GALV-RRV, and opens the door to the possibility of future combination gene therapy with CD-armed MLV-RRV, as the latter vector is currently being evaluated in clinical trials.


Assuntos
Aziridinas/farmacologia , Neoplasias Encefálicas/terapia , Flucitosina/farmacologia , Terapia Genética , Vetores Genéticos , Glioma/terapia , Neoplasias Experimentais/terapia , Pró-Fármacos/farmacologia , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Citosina Desaminase/biossíntese , Citosina Desaminase/genética , Proteínas de Escherichia coli/biossíntese , Proteínas de Escherichia coli/genética , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Vírus da Leucemia do Macaco Gibão , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Nitrorredutases/biossíntese , Nitrorredutases/genética , Ratos Endogâmicos F344 , Proteínas de Saccharomyces cerevisiae/biossíntese , Proteínas de Saccharomyces cerevisiae/genética
7.
Neurochem Res ; 44(11): 2517-2526, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31512113

RESUMO

Endoplasmic reticulum (ER) stress has been indicated to be involved in the pathogenesis of epilepsy. Sodium valproate (VPA), one of the most commonly used antiepileptic drugs, is reported to regulate ER stress in many neurological diseases. However, the effect of VPA on ER stress in epilepsy remains unclear. The current study was performed to investigate the role of ER stress in the neuroprotection of VPA against seizure induced by pentylenetetrzole (PTZ). Our results showed that VPA treatment could inhibit the increased expressions of ER stress proteins (GRP78 and CHOP), and significantly reduce neuronal apoptosis in the PTZ-induced experimental seizure model. In addition, Salubrinal, an ER stress inhibitor, was used as a positive control, and exhibited neuroprotective effects via inhibiting excessive ER stress in the seizure model, which further supported that the inhibition in ER stress by VPA treatment could exert neuroprotection in seizures. In summary, our work demonstrated for the first time that ER stress was involved in the neuroprotective potential of VPA for seizures.


Assuntos
Anticonvulsivantes/uso terapêutico , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Convulsões/tratamento farmacológico , Ácido Valproico/uso terapêutico , Animais , Cinamatos/uso terapêutico , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Camundongos Endogâmicos C57BL , Pentilenotetrazol , Convulsões/induzido quimicamente , Tioureia/análogos & derivados , Tioureia/uso terapêutico , Fator de Transcrição CHOP/metabolismo
8.
Int J Mol Sci ; 19(12)2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30563210

RESUMO

Intracranial malignancies, such as primary brain cancers and brain-localized metastases derived from peripheral cancers, are particularly difficult to treat with therapeutic agents, because the blood-brain barrier (BBB) effectively minimizes brain entry of the vast majority of agents arriving from the systemic circulation. Intranasal administration of cancer drugs has the potential to reach the brain via direct nose-to-brain transport, thereby circumventing the obstacle posed by the BBB. However, in the field of cancer therapy, there is a paucity of studies reporting positive results with this type of approach. A remarkable exception is the natural compound perillyl alcohol (POH). Its potent anticancer activity was convincingly established in preclinical studies, but it nonetheless failed in subsequent clinical trials, where it was given orally and displayed hard-to-tolerate gastrointestinal side effects. Intriguingly, when switched to intranasal delivery, POH yielded highly promising activity in recurrent glioma patients and was well tolerated. As of 2018, POH is the only intranasally delivered compound in the field of cancer therapy (outside of cancer pain) that has advanced to active clinical trials. In the following, we will introduce this compound, summarize its molecular mechanisms of action, and present the latest data on its clinical evaluation as an intranasally administered agent for glioma.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Monoterpenos/administração & dosagem , Administração Intranasal , Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Ensaios Clínicos como Assunto , Glioma/metabolismo , Humanos , Monoterpenos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
9.
Int J Mol Sci ; 19(1)2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29342125

RESUMO

Despite the introduction of new therapies for multiple myeloma (MM), many patients are still dying from this disease and novel treatments are urgently needed. We have designed a novel hybrid molecule, called NEO214, that was generated by covalent conjugation of the natural monoterpene perillyl alcohol (POH), an inducer of endoplasmic reticulum (ER) stress, to rolipram (Rp), an inhibitor of phosphodiesterase-4 (PDE4). Its potential anticancer effects were investigated in a panel of MM cell lines. We found that NEO214 effectively killed MM cells in vitro with a potency that was over an order of magnitude stronger than that of its individual components, either alone or in combination. The cytotoxic mechanism of NEO214 involved severe ER stress and prolonged induction of CCAAT/enhancer-binding protein homologous protein (CHOP), a key pro-apoptotic component of the ER stress response. These effects were prevented by salubrinal, a pharmacologic inhibitor of ER stress, and by CHOP gene knockout. Conversely, combination of NEO214 with bortezomib, a drug in clinical use for patients with MM, resulted in synergistic enhancement of MM cell death. Combination with the adenylate cyclase stimulant forskolin did not enhance NEO214 impact, indicating that cyclic adenosine 3',5'-monophosphate (AMP) pathways might play a lesser role. Our study introduces the novel agent NEO214 as a potent inducer of ER stress with significant anti-MM activity in vitro. It should be further investigated as a potential MM therapy aimed at exploiting this tumor's distinct sensitivity to ER stress.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Monoterpenos , Mieloma Múltiplo/metabolismo , Rolipram/farmacologia , Antineoplásicos/química , Biomarcadores , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Monoterpenos/química , Mieloma Múltiplo/patologia , Inibidores da Fosfodiesterase 4/química , Inibidores da Fosfodiesterase 4/farmacologia , Rolipram/química
10.
Int J Mol Sci ; 19(9)2018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-30150597

RESUMO

Glioblastoma is the most common form of brain cancer in adults that produces severe damage to the brain leading to a very poor survival prognosis. The standard of care for glioblastoma is usually surgery, as well as radiotherapy followed by systemic temozolomide chemotherapy, resulting in a median survival time of about 12 to 15 months. Despite these therapeutic efforts, the tumor returns in the vast majority of patients. When relapsing, statistics suggest an imminent death dependent on the size of the tumor, the Karnofsky Performance Status, and the tumor localization. Following the standard of care, the administration of Bevacizumab, inhibiting the growth of the tumor vasculature, is an approved medicinal treatment option approved in the United States, but not in the European Union, as well as the recently approved alternating electric fields (AEFs) generator NovoTTF/Optune. However, it is clear that regardless of the current treatment regimens, glioma patients continue to have dismal prognosis and novel treatments are urgently needed. Here, we describe different approaches of recently developed therapeutic glioma brain cancer vaccines, which stimulate the patient's immune system to recognize tumor-associated antigens (TAA) on cancer cells, aiming to instruct the immune system to eventually attack and destroy the brain tumor cells, with minimal bystander damage to normal brain cells. These distinct immunotherapies may target particular glioma TAAs which are molecularly defined, but they may also target broad patient-derived tumor antigen preparations intentionally evoking a very broad polyclonal antitumor immune stimulation.


Assuntos
Neoplasias Encefálicas/imunologia , Vacinas Anticâncer/imunologia , Glioblastoma/imunologia , Imunização/métodos , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Encéfalo/patologia , Neoplasias Encefálicas/tratamento farmacológico , Vacinas Anticâncer/uso terapêutico , Glioblastoma/tratamento farmacológico , Humanos , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/imunologia , Análise de Sobrevida
11.
Molecules ; 23(11)2018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30413113

RESUMO

We developed a bacterial expression system to produce a recombinant disintegrin, vicrostatin (VCN), whose structure is based on a natural disintegrin isolated from southern copperhead snake venom. Our goal is to develop VCN for potential clinical translation as an anti-cancer agent. VCN is a peptide of 69 amino acids with a single tyrosine residue. We have employed VCN as integrin-targeted radionuclide therapy (brachytherapy) for treatment of glioblastoma (GBM, glioma). GBM is a deadly brain cancer that doesn't discriminate between sexes and knows no age limit. We established that the tyrosine residue in VCN can be radioiodinated with full retention of bioactivity. 131I-VCN was utilized for integrin-targeted radionuclide therapy using mouse models of glioma. The combination of radioiodinated VCN plus temozolomide (a DNA alkylating agent) significantly prolonged survival of glioma-bearing mice. We also obtained similar results using an immunocompetent mouse model and a murine glioma cell line. In summary, as demonstrated in studies reported here we have shown that VCN as targeted radionuclide therapy for GBM has significant translational potential for therapy of this deadly disease.


Assuntos
Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Radioisótopos do Iodo/química , Proteínas Recombinantes/química , Venenos de Serpentes/genética , Animais , Braquiterapia , Neoplasias Encefálicas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Desintegrinas/química , Desintegrinas/genética , Desintegrinas/metabolismo , Sinergismo Farmacológico , Glioblastoma/tratamento farmacológico , Humanos , Camundongos , Venenos de Serpentes/metabolismo , Temozolomida/administração & dosagem , Temozolomida/farmacologia , Tirosina/química , Ensaios Antitumorais Modelo de Xenoenxerto
12.
J Neurosci Res ; 94(12): 1511-1519, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27629382

RESUMO

Medulloblastomas are the most common malignant pediatric brain tumors. Over the past several decades, a wide range of tumor-centric studies have identified genes and their regulators within signaling pathways that promote medulloblastoma growth. This review aims to raise awareness that transdisciplinary research between developmental neurobiology and cancer foundations can advance our current understanding of how the nervous system contributes to medulloblastomas. By leveraging current advances in neurodevelopment, microenvironment (including secreted neuropeptides), neurotransmitters, and axon guidance cues, we can uncover novel mechanisms used by the nervous system to promote medulloblastoma growth and spread. This will ultimately result in development of improved strategies for cancer prevention and treatment of pediatric patients with this devastating disease. © 2016 Wiley Periodicals, Inc.


Assuntos
Neoplasias Cerebelares/patologia , Meduloblastoma/patologia , Sistema Nervoso/crescimento & desenvolvimento , Transdução de Sinais , Microambiente Tumoral , Animais , Neoplasias Cerebelares/fisiopatologia , Humanos , Meduloblastoma/fisiopatologia , Metástase Neoplásica
13.
Int J Mol Sci ; 17(9)2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27598140

RESUMO

Metastasis to the central nervous system remains difficult to treat, and such patients are faced with a dismal prognosis. The blood-brain barrier (BBB), despite being partially compromised within malignant lesions in the brain, still retains much of its barrier function and prevents most chemotherapeutic agents from effectively reaching the tumor cells. Here, we review some of the recent developments aimed at overcoming this obstacle in order to more effectively deliver chemotherapeutic agents to the intracranial tumor site. These advances include intranasal delivery to achieve direct nose-to-brain transport of anticancer agents and covalent modification of existing drugs to support enhanced penetration of the BBB. In both of these areas, use of the natural product perillyl alcohol, a monoterpene with anticancer properties, contributed to promising new results, which will be discussed here.


Assuntos
Antineoplásicos/farmacocinética , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Portadores de Fármacos/farmacocinética , Monoterpenos/farmacocinética , Administração Intranasal , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/secundário , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/uso terapêutico , Humanos , Monoterpenos/administração & dosagem , Monoterpenos/uso terapêutico
14.
J Biomed Sci ; 22: 71, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26282951

RESUMO

BACKGROUND: Many patients with nasopharyngeal carcinoma (NPC) face poor prognosis. Due to its hidden anatomical location, the tumor is usually diagnosed quite late, and despite initially successful treatment with radiation and cisplatin, many patients will relapse and succumb to the disease. New treatment options are urgently needed. We have performed preclinical studies to evaluate the potential NPC therapeutic activity of a newly developed analog of temozolomide (TMZ), an alkylating agent that is the current chemotherapeutic standard of care for patients with malignant glioma. RESULTS: TMZ was covalently conjugated to the natural monoterpene perillyl alcohol (POH), creating the novel fusion compound NEO212. Its impact on two NPC cell lines was studied through colony formation assays, cell death ELISA, immunoblots, and in vivo testing in tumor-bearing mice. In vitro, NEO212 effectively triggered tumor cell death, and its potency was significantly greater than that of its individual components, TMZ or POH alone. Intriguingly, merely mixing TMZ with POH also was unable to achieve the superior potency of the conjugated compound NEO212. Treatment of NPC cells with NEO212 inactivated the chemoprotective DNA repair protein MGMT (O6-methylguanine methyltransferase), resulting in significant chemosensitization of cells to a second round of drug treatment. When tested in vivo, NEO212 reduced tumor growth in treated animals. CONCLUSION: Our results demonstrate anticancer activity of NEO212 in preclinical NPC models, suggesting that this novel compound should be evaluated further for the treatment of patients with NPC.


Assuntos
Dacarbazina/análogos & derivados , Neoplasias Nasofaríngeas/tratamento farmacológico , Animais , Carcinoma , Metilases de Modificação do DNA/antagonistas & inibidores , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/antagonistas & inibidores , Enzimas Reparadoras do DNA/metabolismo , Dacarbazina/farmacologia , Humanos , Camundongos , Camundongos Nus , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/enzimologia , Neoplasias Nasofaríngeas/patologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Temozolomida , Proteínas Supressoras de Tumor/antagonistas & inibidores , Proteínas Supressoras de Tumor/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Neurosurg Focus ; 38(3): E12, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25727221

RESUMO

OBJECT: Chloroquine (CQ) is a quinoline-based drug widely used for the prevention and treatment of malaria. More recent studies have provided evidence that this drug may also harbor antitumor properties, whereby CQ possesses the ability to accumulate in lysosomes and blocks the cellular process of autophagy. Therefore, the authors of this study set out to investigate whether CQ analogs, in particular clinically established antimalaria drugs, would also be able to exert antitumor properties, with a specific focus on glioma cells. METHODS: Toward this goal, the authors treated different glioma cell lines with quinine (QN), quinacrine (QNX), mefloquine (MFQ), and hydroxychloroquine (HCQ) and investigated endoplasmic reticulum (ER) stress-induced cell death, autophagy, and cell death. RESULTS: All agents blocked cellular autophagy and exerted cytotoxic effects on drug-sensitive and drug-resistant glioma cells with varying degrees of potency (QNX > MFQ > HCQ > CQ > QN). Furthermore, all quinoline-based drugs killed glioma cells that were highly resistant to temozolomide (TMZ), the current standard of care for patients with glioma. The cytotoxic mechanism involved the induction of apoptosis and ER stress, as indicated by poly(ADP-ribose) polymerase (PARP) cleavage and CHOP/GADD153. The induction of ER stress and resulting apoptosis could be confirmed in the in vivo setting, in which tumor tissues from animals treated with quinoline-based drugs showed increased expression of CHOP/GADD153, along with elevated TUNEL staining, a measure of apoptosis. CONCLUSIONS: Thus, the antimalarial compounds investigated in this study hold promise as a novel class of autophagy inhibitors for the treatment of newly diagnosed TMZ-sensitive and recurrent TMZ-resistant gliomas.


Assuntos
Antimaláricos/uso terapêutico , Autofagia/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Quinolinas/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos Nus , Poli(ADP-Ribose) Polimerases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Neurosurg Focus ; 38(3): E8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25727230

RESUMO

OBJECT Bevacizumab (Avastin), an antibody to vascular endothelial growth factor (VEGF), alone or in combination with irinotecan (Camptosar [CPT-11]), is a promising treatment for recurrent glioblastoma. However, the intravenous (IV) administration of bevacizumab produces a number of systemic side effects, and the increase in survival it provides for patients with recurrent glioblastoma is still only a few months. Because bevacizumab is an antibody against VEGF, which is secreted into the extracellular milieu by glioma cells, the authors hypothesized that direct chronic intratumoral delivery techniques (i.e., convection-enhanced delivery [CED]) can be more effective than IV administration. To test this hypothesis, the authors compared outcomes for these routes of bevacizumab application with respect to animal survival, microvessel density (MVD), and inflammatory cell distribution. METHODS Two human glioma cell lines, U87 and U251, were used as sources of intracranial tumor cells. The glioma cell lines were implanted into the brains of mice in an orthotopic xenograft mouse tumor model. After 7 days, the mice were treated with one of the following: 1) vehicle, 2) CED bevacizumab, 3) IV bevacizumab, 4) intraperitoneal (IP) irinotecan, 5) CED bevacizumab plus IP irinotecan, or 6) IV bevacizumab plus IP irinotecan. Alzet micro-osmotic pumps were used to introduce bevacizumab directly into the tumor. Survival was monitored. Excised tumor tissue samples were immunostained to measure MVD and inflammatory cell and growth factor levels. RESULTS The results demonstrate that mice treated with CED of bevacizumab alone or in combination with irinotecan survived longer than those treated systemically; CED-treated animals survived 30% longer than IV-treated animals. In combination studies, CED bevacizumab plus CPT-11 increased survival by more than 90%, whereas IV bevacizumab plus CPT-11 increased survival by 40%. Furthermore, CED bevacizumab-treated tissues exhibited decreased MVD compared with that of IV-treated tissues. In additional studies, the infiltration of macrophages and dendritic cells into CED-treated animals were increased compared with those in IV-treated animals, suggesting a highly active inflammatory response taking place in CED-treated mice. CONCLUSIONS The administration of bevacizumab via CED increases survival over that of treatment with IV bevacizumab. Thus, CED of bevacizumab alone or in combination with chemotherapy can be an effective protocol for treating gliomas.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Bevacizumab/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/mortalidade , Glioma/tratamento farmacológico , Glioma/mortalidade , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Linhagem Celular Tumoral , Células Dendríticas/patologia , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Quimioterapia Combinada , Humanos , Irinotecano , Camundongos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
JAMA ; 314(23): 2535-43, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26670971

RESUMO

IMPORTANCE: Glioblastoma is the most devastating primary malignancy of the central nervous system in adults. Most patients die within 1 to 2 years of diagnosis. Tumor-treating fields (TTFields) are a locoregionally delivered antimitotic treatment that interferes with cell division and organelle assembly. OBJECTIVE: To evaluate the efficacy and safety of TTFields used in combination with temozolomide maintenance treatment after chemoradiation therapy for patients with glioblastoma. DESIGN, SETTING, AND PARTICIPANTS: After completion of chemoradiotherapy, patients with glioblastoma were randomized (2:1) to receive maintenance treatment with either TTFields plus temozolomide (n = 466) or temozolomide alone (n = 229) (median time from diagnosis to randomization, 3.8 months in both groups). The study enrolled 695 of the planned 700 patients between July 2009 and November 2014 at 83 centers in the United States, Canada, Europe, Israel, and South Korea. The trial was terminated based on the results of this planned interim analysis. INTERVENTIONS: Treatment with TTFields was delivered continuously (>18 hours/day) via 4 transducer arrays placed on the shaved scalp and connected to a portable medical device. Temozolomide (150-200 mg/m2/d) was given for 5 days of each 28-day cycle. MAIN OUTCOMES AND MEASURES: The primary end point was progression-free survival in the intent-to-treat population (significance threshold of .01) with overall survival in the per-protocol population (n = 280) as a powered secondary end point (significance threshold of .006). This prespecified interim analysis was to be conducted on the first 315 patients after at least 18 months of follow-up. RESULTS: The interim analysis included 210 patients randomized to TTFields plus temozolomide and 105 randomized to temozolomide alone, and was conducted at a median follow-up of 38 months (range, 18-60 months). Median progression-free survival in the intent-to-treat population was 7.1 months (95% CI, 5.9-8.2 months) in the TTFields plus temozolomide group and 4.0 months (95% CI, 3.3-5.2 months) in the temozolomide alone group (hazard ratio [HR], 0.62 [98.7% CI, 0.43-0.89]; P = .001). Median overall survival in the per-protocol population was 20.5 months (95% CI, 16.7-25.0 months) in the TTFields plus temozolomide group (n = 196) and 15.6 months (95% CI, 13.3-19.1 months) in the temozolomide alone group (n = 84) (HR, 0.64 [99.4% CI, 0.42-0.98]; P = .004). CONCLUSIONS AND RELEVANCE: In this interim analysis of 315 patients with glioblastoma who had completed standard chemoradiation therapy, adding TTFields to maintenance temozolomide chemotherapy significantly prolonged progression-free and overall survival. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00916409.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/terapia , Dacarbazina/análogos & derivados , Terapia por Estimulação Elétrica/métodos , Glioblastoma/terapia , Quimioterapia de Manutenção/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Canadá , Carmustina/uso terapêutico , Quimiorradioterapia , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Dacarbazina/uso terapêutico , Progressão da Doença , Intervalo Livre de Doença , Término Precoce de Ensaios Clínicos , Terapia por Estimulação Elétrica/efeitos adversos , Europa (Continente) , Feminino , Glioblastoma/mortalidade , Humanos , Israel , Masculino , Pessoa de Meia-Idade , República da Coreia , Temozolomida , Estados Unidos , Adulto Jovem
18.
Stroke ; 45(1): 293-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24203843

RESUMO

BACKGROUND AND PURPOSE: Cerebral arteriovenous malformation (AVM) is a vascular disease that disrupts normal blood flow and leads to serious neurological impairment or death. Aberrant functions of AVM-derived brain endothelial cells (AVM-BECs) are a disease hallmark. Our aim was to use microRNA-18a (miR-18a) as a therapeutic agent to improve AVM-BEC function. METHODS: Human AVM-BECs were tested for growth factor production and proliferation under different shear flow conditions and evaluated for tubule formation. Thrombospondin-1, inhibitor of DNA-binding protein 1, and vascular endothelial growth factor (VEGF) isotype mRNA levels were quantified by quantitative real-time polymerase chain reaction. Thrombospondin-1, VEGF-A, and VEGF-D protein expression was measured using enzyme-linked immunosorbent assay. Proliferation and tubule formation were evaluated using bromodeoxyuridine incorporation and growth factor-reduced Matrigel assays, respectively. RESULTS: miR-18a increased thrombospondin-1 production but decreased inhibitor of DNA-binding protein 1, a transcriptional repressor of thrombospondin-1. miR-18a reduced VEGF-A and VEGF-D levels, both overexpressed in untreated AVM-BECs. This is the first study reporting VEGF-D overexpression in AVM. These effects were most prominent under arterial shear flow conditions. miR-18a also reduced AVM-BEC proliferation, improved tubule formation, and was effectively internalized by AVM-BECs in the absence of extraneous transfection reagents. CONCLUSIONS: We report VEGF-D overexpression in AVM and the capacity of miR-18a to induce AVM-BECs to function more normally. This highlights the clinical potential of microRNA as a treatment for AVM and other vascular diseases.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/tratamento farmacológico , Células Endoteliais/efeitos dos fármacos , MicroRNAs/uso terapêutico , Angiografia , Antimetabólitos , Encéfalo/citologia , Encéfalo/patologia , Bromodesoxiuridina , Proliferação de Células/efeitos dos fármacos , Malformações Vasculares do Sistema Nervoso Central/patologia , Circulação Cerebrovascular/efeitos dos fármacos , Circulação Cerebrovascular/fisiologia , Expressão Gênica/efeitos dos fármacos , Humanos , Proteína 1 Inibidora de Diferenciação/metabolismo , Microtúbulos/efeitos dos fármacos , Trombospondinas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator D de Crescimento do Endotélio Vascular/metabolismo
19.
J Neurooncol ; 116(3): 437-46, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24398618

RESUMO

The intranasal route for drug delivery is rapidly evolving as a viable means for treating selected central nervous system (CNS) conditions. We aimed to identify studies pertaining to the application of intranasal drug administration for the treatment of primary CNS tumors. A systematic literature review was conducted to identify all studies published in the English language pertaining to intranasal therapy for CNS neoplasms, and/or general mechanisms and pharmacokinetics regarding targeted intranasal CNS drug delivery. A total of 194 abstracts were identified and screened. Thirty-seven studies met inclusion criteria. Of these, 21 focused on intranasal treatment of specific primary CNS tumors, including gliomas (11), meningiomas (1), and pituitary adenomas (4). An additional 16 studies focused on general mechanisms of intranasal therapy and drug delivery to the CNS using copolymer micelles, viral vectors, and nanoparticles. Inhaled compounds/substances investigated included perillyl alcohol, vesicular stomatitis virus, parvovirus, telomerase inhibitors, neural stem and progenitor cells, antimetabolites, somatostatin analogues, and dopamine agonists. Radiolabeling, CSF concentration measurement, imaging studies, and histological examination were utilized to clarify the mechanism and distribution by which drugs were delivered to the CNS. Successful drug delivery and tumor/symptom response was reported in all 21 tumor-specific studies. The intranasal route holds tremendous potential as a viable option for drug delivery for CNS neoplasms. A variety of antitumoral agents may be delivered via this route, thereby potentially offering a more direct delivery approach and ameliorating the adverse effects associated with systemic drug delivery.


Assuntos
Administração Intranasal/métodos , Antineoplásicos/administração & dosagem , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Humanos
20.
Neurosurg Focus ; 37(6): E12, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25434381

RESUMO

OBJECT: In a recent clinical trial, patients with newly diagnosed glioblastoma multiforme benefited from chloroquine (CQ) in combination with conventional therapy (resection, temozolomide [TMZ], and radiation therapy). In the present study, the authors report the mechanism by which CQ enhances the therapeutic efficacy of TMZ to aid future studies aimed at improving this therapeutic regimen. METHODS: Using in vitro and in vivo experiments, the authors determined the mechanism by which CQ enhances TMZ cytotoxicity. They focused on the inhibition-of-autophagy mechanism of CQ by knockdown of the autophagy-associated proteins or treatment with autophagy inhibitors. This mechanism was tested using an in vivo model with subcutaneously implanted U87MG tumors from mice treated with CQ in combination with TMZ. RESULTS: Knockdown of the autophagy-associated proteins (GRP78 and Beclin) or treatment with the autophagy inhibitor, 3-methyl adenine (3-MA), blocked autophagosome formation and reduced CQ cytotoxicity, suggesting that autophagosome accumulation precedes CQ-induced cell death. In contrast, blocking autophagosome formation with knockdown of GRP78 or treatment with 3-MA enhanced TMZ cytotoxicity, suggesting that the autophagy pathway protects from TMZ-induced cytotoxicity. CQ in combination with TMZ significantly increased the amounts of LC3B-II (a marker for autophagosome levels), CHOP/GADD-153, and cleaved PARP (a marker for apoptosis) over those with untreated or individual drug-treated glioma cells. These molecular mechanisms seemed to take place in vivo as well. Subcutaneously implanted U87MG tumors from mice treated with CQ in combination with TMZ displayed higher levels of CHOP/GADD-153 than did untreated or individual drug-treated tumors. CONCLUSIONS: Taken together, these results demonstrate that CQ blocks autophagy and triggers endoplasmic reticulum stress, thereby increasing the chemosensitivity of glioma cells to TMZ.


Assuntos
Antineoplásicos Alquilantes/efeitos adversos , Antirreumáticos/efeitos adversos , Autofagia/efeitos dos fármacos , Cloroquina/efeitos adversos , Cloroquina/farmacologia , Dacarbazina/análogos & derivados , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dacarbazina/efeitos adversos , Sinergismo Farmacológico , Chaperona BiP do Retículo Endoplasmático , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Nus , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Temozolomida , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
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