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1.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34740973

RESUMO

Tumor antigen heterogeneity, a severely immunosuppressive tumor microenvironment (TME) and lymphopenia resulting in inadequate immune intratumoral trafficking, have rendered glioblastoma (GBM) highly resistant to therapy. To address these obstacles, here we describe a unique, sophisticated combinatorial platform for GBM: a cooperative multifunctional immunotherapy based on genetically engineered human natural killer (NK) cells bearing multiple antitumor functions including local tumor responsiveness that addresses key drivers of GBM resistance to therapy: antigen escape, immunometabolic reprogramming of immune responses, and poor immune cell homing. We engineered dual-specific chimeric antigen receptor (CAR) NK cells to bear a third functional moiety that is activated in the GBM TME and addresses immunometabolic suppression of NK cell function: a tumor-specific, locally released antibody fragment which can inhibit the activity of CD73 independently of CAR signaling and decrease the local concentration of adenosine. The multifunctional human NK cells targeted patient-derived GBM xenografts, demonstrated local tumor site-specific activity in the tissue, and potently suppressed adenosine production. We also unveil a complex reorganization of the immunological profile of GBM induced by inhibiting autophagy. Pharmacologic impairment of the autophagic process not only sensitized GBM to antigenic targeting by NK cells but promoted a chemotactic profile favorable to NK infiltration. Taken together, our study demonstrates a promising NK cell-based combinatorial strategy that can target multiple clinically recognized mechanisms of GBM progression simultaneously.


Assuntos
Engenharia Genética , Glioblastoma/terapia , Imunoterapia Adotiva , Células Matadoras Naturais , Microambiente Tumoral/imunologia , Animais , Autofagia , Glioblastoma/imunologia , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Mol Pharm ; 19(8): 2776-2794, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35834797

RESUMO

For many locally advanced tumors, the chemotherapy-radiotherapy (CT-RT) combination ("chemoradiation") is currently the standard of care. Intratumoral (IT) CT-based chemoradiation has the potential to overcome the limitations of conventional systemic CT-RT (side effects). For maximizing the benefits of IT CT-RT, our laboratory has previously developed a radiation-controlled drug release formulation, in which anticancer drug paclitaxel (PTX) and radioluminescent CaWO4 (CWO) nanoparticles (NPs) are co-encapsulated with poly(ethylene glycol)-poly(lactic acid) (PEG-PLA) block copolymers ("PEG-PLA/CWO/PTX NPs"). These PEG-PLA/CWO/PTX NPs enable radiation-controlled release of PTX and are capable of producing sustained therapeutic effects lasting for at least one month following a single IT injection. The present article focuses on discussing our recent finding about the effect of the stereochemical structure of PTX on the efficacy of this PEG-PLA/CWO/PTX NP formulation. Stereochemical differences in two different PTX compounds ("PTX-S" from Samyang Biopharmaceuticals and "PTX-B" from Biotang) were characterized by 2D heteronuclear/homonuclear NMR, Raman spectroscopy, and circular dichroism measurements. The difference in PTX stereochemistry was found to significantly influence their water solubility (WS); PTX-S (WS ≈ 4.69 µg/mL) is about 19 times more water soluble than PTX-B (WS ≈ 0.25 µg/mL). The two PTX compounds showed similar cancer cell-killing performances in vitro when used as free drugs. However, the subtle stereochemical difference significantly influenced their X-ray-triggered release kinetics from the PEG-PLA/CWO/PTX NPs; the more water-soluble PTX-S was released faster than the less water-soluble PTX-B. This difference was manifested in the IT pharmacokinetics and eventually in the survival percentages of test animals (mice) treated with PEG-PLA/CWO/PTX NPs + X-rays in an in vivo human tumor xenograft study; at short times (<1 month), concurrent PEG-PLA/CWO/PTX-S NPs produced a greater tumor-suppression effect, whereas PEG-PLA/CWO/PTX-B NPs had a longer-lasting radio-sensitizing effect. This study demonstrates the importance of the stereochemistry of a drug in a therapy based on a controlled release formulation.


Assuntos
Nanopartículas , Neoplasias , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/química , Humanos , Camundongos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Paclitaxel/química , Polietilenoglicóis/química , Água , Raios X
3.
Biomacromolecules ; 23(6): 2471-2484, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35580262

RESUMO

We have recently discovered that pulmonary administration of nanoparticles (micelles) formed by amphiphilic poly(styrene-block-ethylene glycol) (PS-PEG) block copolymers has the potential to treat a lung disorder involving lung surfactant (LS) dysfunction (called acute respiratory distress syndrome (ARDS)), as PS-PEG nanoparticles are capable of reducing the surface tension of alveolar fluid, while they are resistant to deactivation caused by plasma proteins/inflammation products unlike natural LS. Herein, we report studies of the clearance pathways and kinetics of PS-PEG nanoparticles from the lung, which are essential for designing further preclinical IND-enabling studies. Using fluorescently labeled PS-PEG nanoparticles, we found that, following pharyngeal aspiration in mice, the retention of these nanoparticles in the lungs extends over 2 weeks, while their transport into other (secondary) organs is relatively insignificant. An analysis based on a multicompartmental pharmacokinetic model suggests a biphasic mechanism involving a fast mucociliary escalator process through the conducting airways and much slower alveolar clearance processes by the action of macrophages and also via direct translocation into the circulation. An excessive dose of PS-PEG nanoparticles led to prolonged retention in the lungs due to saturation of the alveolar clearance capacity.


Assuntos
Polietilenoglicóis , Polímeros , Animais , Pulmão , Camundongos , Micelas , Polietilenoglicóis/farmacocinética , Tensoativos
5.
Bioconjug Chem ; 28(1): 171-182, 2017 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-27791362

RESUMO

X-ray computed tomography (CT) is currently one of the most powerful, noninvasive, clinical in vivo imaging techniques, which has resulted from advances in both X-ray device and contrast enhancement technologies. The present study demonstrates, for the first time, that metal tungstates (such as CaWO4) are promising contrast agents for X-ray, radiation, and CT imaging, because of the high X-ray mass attenuation of tungsten (W). We have developed a method of formulation, in which CaWO4 (CWO) nanoparticles (NPs) are encapsulated within a biocompatible poly(ethylene glycol-b-d,l-lactic acid) (PEG-PLA) block copolymer (BCP) capsule. We show that these PEG-PLA-encapsulated CWO NPs (170 ± 10 nm hydrodynamic diameter) produce a higher CT contrast (by a factor of about 2) than commercial iodine-based radiocontrast agents (e.g., Iohexol) at identical molar concentrations of W or I atoms. PEG-PLA-coated CWO NPs are chemically stable and completely nontoxic. It was confirmed that the maximum tolerated dose (MTD) of this material in mice is significantly higher (250 ± 50 mg per kg body weight following a single intravenous (IV) administration) than, for instance, commercially available dextran-coated iron oxide nanoparticles that are currently used clinically as MRI contrast agents (MTD in mice ≈ 168 mg/kg per dose IV). IV-injected PEG-PLA/CWO NPs caused no histopathologic damage in major excretory organs (heart, liver, lungs, spleen, and kidney). When an IV dose of 100 mg/kg was given to mice, the blood circulation half-life was measured to be about 4 h, and more than 90% of the NPs were cleared from the mice within 24 h via the renal and hepatobiliary systems. When intratumorally administered, PEG-PLA-coated CWO NPs showed complete retention in a tumor-bearing mouse model (measurements were made up to 1 week). These results suggest that PEG-PLA-coated CWO NPs are promising materials for use in CT contrast.


Assuntos
Meios de Contraste/química , Nanopartículas , Contagem de Cintilação , Tomografia Computadorizada por Raios X/métodos , Animais , Relação Dose-Resposta a Droga , Camundongos
6.
Biomacromolecules ; 17(9): 2777-86, 2016 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-27387820

RESUMO

Polyrotaxanes, a family of rod-shaped nanomaterials comprised of noncovalent polymer/macrocycle assemblies, are being used in a growing number of materials and biomedical applications. Their physiochemical properties can vary widely as a function of composition, potentially leading to different in vivo performance outcomes. We sought to characterize the pharmacokinetic profiles, toxicities, and protein corona compositions of 2-hydroxypropyl-ß-cyclodextrin polyrotaxanes as a function of variations in macrocycle threading efficiency, molecular weight, and triblock copolymer core structure. We show that polyrotaxane fate in vivo is governed by the structure and dynamics of their rodlike morphologies, such that highly threaded polyrotaxanes are long circulating and deposit in the liver, whereas lung deposition and rapid clearance is observed for species bearing lower 2-hydroxypropyl-ß-cyclodextrin threading percentages. Architecture differences also promote recruitment of different serum protein classes and proportions; however, physiochemical differences have little or no influence on their toxicity. These findings provide important structural insights for guiding the development of polyrotaxanes as scaffolds for biomedical applications.


Assuntos
Ciclodextrinas/química , Ciclodextrinas/farmacologia , Poloxâmero/química , Poloxâmero/farmacologia , Polímeros/química , Rotaxanos/química , Rotaxanos/farmacologia , Animais , Materiais Biocompatíveis , Ciclodextrinas/farmacocinética , Hemólise/efeitos dos fármacos , Humanos , Cinética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Poloxâmero/farmacocinética , Polietilenoglicóis , Rotaxanos/farmacocinética , Distribuição Tecidual
7.
Arch Toxicol ; 89(2): 269-87, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25618548

RESUMO

A major problem in developmental neurotoxicity (DNT) risk assessment is the lack of toxicological hazard information for most compounds. Therefore, new approaches are being considered to provide adequate experimental data that allow regulatory decisions. This process requires a matching of regulatory needs on the one hand and the opportunities provided by new test systems and methods on the other hand. Alignment of academically and industrially driven assay development with regulatory needs in the field of DNT is a core mission of the International STakeholder NETwork (ISTNET) in DNT testing. The first meeting of ISTNET was held in Zurich on 23-24 January 2014 in order to explore the concept of adverse outcome pathway (AOP) to practical DNT testing. AOPs were considered promising tools to promote test systems development according to regulatory needs. Moreover, the AOP concept was identified as an important guiding principle to assemble predictive integrated testing strategies (ITSs) for DNT. The recommendations on a road map towards AOP-based DNT testing is considered a stepwise approach, operating initially with incomplete AOPs for compound grouping, and focussing on key events of neurodevelopment. Next steps to be considered in follow-up activities are the use of case studies to further apply the AOP concept in regulatory DNT testing, making use of AOP intersections (common key events) for economic development of screening assays, and addressing the transition from qualitative descriptions to quantitative network modelling.


Assuntos
Encéfalo/efeitos dos fármacos , Feto/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Testes de Toxicidade/métodos , Guias como Assunto , Humanos , Medição de Risco
8.
J Okla State Med Assoc ; 107(9-10): 501-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25790598

RESUMO

BACKGROUND: Children are especially vulnerable to the effects of disasters. The coming tornado season raises concerns about enduring problems and anniversary reactions related to the May 2013 tornadoes as well as anxiety about the possibility of new events. METHODS: This article describes common emotional and behavioral disaster reactions in children and also identifies reactions unique to a particular age. Reactions are clustered into depressive, anxious, and behavioral symptoms and physiological responses. PRIMARY RESULTS: This article outlines the key elements in assessing children's disaster reactions and provides specific recommendations for situations that would indicate the need for a mental health evaluation such as for directly-exposed children, children who experience disaster-related losses, those with pre-existing vulnerabilities, and those with significant symptoms. PRINCIPAL CONCLUSIONS: Primary care physicians can help identify the emotional and behavioral effects of disasters in children, educate parents to recognize children's reactions, and refer children in need of specialized care.


Assuntos
Desastres , Programas de Rastreamento/normas , Papel do Médico , Médicos de Atenção Primária , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Sobreviventes , Adolescente , Criança , Pré-Escolar , Seguimentos , Guias como Assunto , Humanos , Medição de Risco , Transtornos de Estresse Pós-Traumáticos/psicologia , Sobreviventes/psicologia
10.
Nat Commun ; 15(1): 1909, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429294

RESUMO

Severe heterogeneity within glioblastoma has spurred the notion that disrupting the interplay between multiple elements on immunosuppression is at the core of meaningful anti-tumor responses. T cell immunoreceptor with Ig and ITIM domains (TIGIT) and its glioblastoma-associated antigen, CD155, form a highly immunosuppressive axis in glioblastoma and other solid tumors, yet targeting of TIGIT, a functionally heterogeneous receptor on tumor-infiltrating immune cells, has largely been ineffective as monotherapy, suggesting that disruption of its inhibitory network might be necessary for measurable responses. It is within this context that we show that the usurpation of the TIGIT - CD155 axis via engineered synNotch-mediated activation of induced pluripotent stem cell-derived natural killer (NK) cells promotes transcription factor-mediated activation of a downstream signaling cascade that results in the controlled, localized blockade of CD73 to disrupt purinergic activity otherwise resulting in the production and accumulation of immunosuppressive extracellular adenosine. Such "decoy" receptor engages CD155 binding to TIGIT, but tilts inhibitory TIGIT/CD155 interactions toward activation via downstream synNotch signaling. Usurping activities of TIGIT and CD73 promotes the function of adoptively transferred NK cells into intracranial patient-derived models of glioblastoma and enhances their natural cytolytic functions against this tumor to result in complete tumor eradication. In addition, targeting both receptors, in turn, reprograms the glioblastoma microenvironment via the recruitment of T cells and the downregulation of M2 macrophages. This study demonstrates that TIGIT/CD155 and CD73 are targetable receptor partners in glioblastoma. Our data show that synNotch-engineered pluripotent stem cell-derived NK cells are not only effective mediators of anti-glioblastoma responses within the setting of CD73 and TIGIT/CD155 co-targeting, but represent a powerful allogeneic treatment option for this tumor.


Assuntos
Glioblastoma , Células-Tronco Pluripotentes Induzidas , Células Matadoras Naturais , Humanos , Glioblastoma/terapia , Glioblastoma/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Células Matadoras Naturais/metabolismo , Receptores Imunológicos/metabolismo , Linfócitos T/metabolismo , Microambiente Tumoral , 5'-Nucleotidase/imunologia , 5'-Nucleotidase/metabolismo
11.
Biomater Sci ; 11(18): 6311-6324, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37552121

RESUMO

Photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) prodrug is a clinically tried and proven treatment modality for surface-level lesions. However, its use for deep-seated tumors has been limited due to the poor penetration depth of visible light needed to activate the photosensitizer protoporphyrin IX (PPIX), which is produced from ALA metabolism. Herein, we report the usage of poly(ethylene glycol-b-lactic acid) (PEG-PLA)-encapsulated calcium tungstate (CaWO4, CWO for short) nanoparticles (PEG-PLA/CWO NPs) as energy transducers for X-ray-activated PDT using ALA. Owing to the spectral overlap between radioluminescence afforded by the CWO core and the absorbance of PPIX, these NPs can serve as an in situ visible light activation source during radiotherapy (RT), thereby mitigating the limitation of penetration depth. We demonstrate that this effect is observed across different cell lines with varying radio-sensitivity. Importantly, both PPIX and PEG-PLA/CWO NPs exhibit no significant toxicities at therapeutic doses in the absence of radiation. To assess the efficacy of this approach, we conducted a study using a syngeneic mouse model subcutaneously implanted with inherently radio-resistant 4T1 tumors. The results show a significantly improved prognosis compared to conventional RT, even with as few as 2 fractions of 4 Gy X-rays. Taken together, these results suggest that PEG-PLA/CWO NPs are promising agents for application of ALA-PDT in deep-seated tumors, thereby significantly expanding the utility of the already established treatment strategy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Pró-Fármacos , Animais , Camundongos , Ácido Aminolevulínico/farmacologia , Ácido Aminolevulínico/uso terapêutico , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias/tratamento farmacológico , Nanopartículas/uso terapêutico , Linhagem Celular Tumoral
12.
Bioact Mater ; 27: 168-180, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37091063

RESUMO

Adoptive chimeric antigen receptor (CAR)-engineered natural killer (NK) cells have shown promise in treating various cancers. However, limited immunological memory and access to sufficient numbers of allogenic donor cells have hindered their broader preclinical and clinical applications. Here, we first assess eight different CAR constructs that use an anti-PD-L1 nanobody and/or universal anti-fluorescein (FITC) single-chain variable fragment (scFv) to enhance antigen-specific proliferation and anti-tumor cytotoxicity of NK-92 cells against heterogenous solid tumors. We next genetically engineer human pluripotent stem cells (hPSCs) with optimized CARs and differentiate them into functional dual CAR-NK cells. The tumor microenvironment responsive anti-PD-L1 CAR effectively promoted hPSC-NK cell proliferation and cytotoxicity through antigen-dependent activation of phosphorylated STAT3 (pSTAT3) and pSTAT5 signaling pathways via an intracellular truncated IL-2 receptor ß-chain (ΔIL-2Rß) and STAT3-binding tyrosine-X-X-glutamine (YXXQ) motif. Anti-tumor activities of PD-L1-induced memory-like hPSC-NK cells were further boosted by administering a FITC-folate bi-specific adapter that bridges between a programmable anti-FITC CAR and folate receptor alpha-expressing breast tumor cells. Collectively, our hPSC CAR-NK engineering platform is modular and could constitute a realistic strategy to manufacture off-the-shelf CAR-NK cells with immunological memory-like phenotype for targeted immunotherapy.

13.
Nat Commun ; 14(1): 2266, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37080958

RESUMO

Glioblastoma (GBM) is one of the most aggressive and lethal solid tumors in human. While efficacious therapeutics, such as emerging chimeric antigen receptor (CAR)-T cells and chemotherapeutics, have been developed to treat various cancers, their effectiveness in GBM treatment has been hindered largely by the blood-brain barrier and blood-brain-tumor barriers. Human neutrophils effectively cross physiological barriers and display effector immunity against pathogens but the short lifespan and resistance to genome editing of primary neutrophils have limited their broad application in immunotherapy. Here we genetically engineer human pluripotent stem cells with CRISPR/Cas9-mediated gene knock-in to express various anti-GBM CAR constructs with T-specific CD3ζ or neutrophil-specific γ-signaling domains. CAR-neutrophils with the best anti-tumor activity are produced to specifically and noninvasively deliver and release tumor microenvironment-responsive nanodrugs to target GBM without the need to induce additional inflammation at the tumor sites. This combinatory chemo-immunotherapy exhibits superior and specific anti-GBM activities, reduces off-target drug delivery and prolongs lifespan in female tumor-bearing mice. Together, this biomimetic CAR-neutrophil drug delivery system is a safe, potent and versatile platform for treating GBM and possibly other devastating diseases.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Nanopartículas , Camundongos , Feminino , Humanos , Animais , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Imunoterapia Adotiva , Neutrófilos , Linfócitos T , Microambiente Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Imunoterapia , Nanopartículas/uso terapêutico
14.
iScience ; 26(12): 108353, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38053639

RESUMO

TIGIT is a receptor on human natural killer (NK) cells. Here, we report that TIGIT does not spontaneously induce inhibition of NK cells in glioblastoma (GBM), but rather acts as a decoy-like receptor, by usurping binding partners and regulating expression of NK activating ligands and receptors. Our data show that in GBM patients, one of the underpinnings of unresponsiveness to TIGIT blockade is that by targeting TIGIT, NK cells do not lose an inhibitory signal, but gains the potential for new interactions with other, shared, TIGIT ligands. Therefore, TIGIT does not define NK cell dysfunction in GBM. Further, in GBM, TIGIT+ NK cells are hyperfunctional. In addition, we discovered that 4-1BB correlates with TIGIT expression, the agonism of which contributes to TIGIT immunotherapy. Overall, our data suggest that in GBM, TIGIT acts as a regulator of a complex network, and provide new clues about its use as an immunotherapeutic target.

15.
Int J Emerg Ment Health ; 14(3): 189-96, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23894799

RESUMO

Changes in relationships, roles, and dynamics associated with deployment of troops to the Global War on Terror can create challenges for their families as non-deployed spouses and their children take on new responsibilities. Children, aged 6 to 18 years, of deployed National Guard troops were assessed to determine the children's perceptions about how their father's deployment would or did change them and their family, the burden the children experienced in relation to helping their mothers, and child- and parent-reported emotional and behavioral symptoms in the children. Endorsement of personal change was associated with psychological health. During deployment, recognizing personal change was associated with less perceived burden while perceived change in the family was associated with more perceived burden. In general, increased perception of burden was associated with increased psychological symptoms and problems. The children of deployed service personnel may experience burdens and challenges in relation to the changes associated with the circumstances of deployment. Helping children prepare for and manage changes in relationships, roles, rules, and routines may lessen adverse reactions to changes in the environment.


Assuntos
Atitude , Guerra do Iraque 2003-2011 , Militares/psicologia , Relações Pais-Filho , Privação Paterna , Terrorismo/psicologia , Adaptação Psicológica , Adolescente , Sintomas Afetivos/diagnóstico , Sintomas Afetivos/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Criança , Transtornos do Comportamento Infantil/diagnóstico , Transtornos do Comportamento Infantil/psicologia , Feminino , Humanos , Controle Interno-Externo , Masculino , Relações Mãe-Filho , Oklahoma , Determinação da Personalidade/estatística & dados numéricos , Psicometria , Família Monoparental , Estados Unidos
16.
Prog Community Health Partnersh ; 16(2): 235-247, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35662150

RESUMO

BACKGROUND: Community collaboration is a founding principle of the Early Success Coalition (ESC), a collaborative of over 74 agencies, engaging over 200 participants. The ESC aims to develop a comprehensive neighborhood young-child-wellness system model to better foster cognitive, physical, and social-emotional development of young children. The Wilder Collaborative Factors Inventory (WCFI) was used, as part of a participatory mixed-methods evaluation, to collect annual measures of collaboration. OBJECTIVE: To reflect on lessons learned, resulting from 4 years of ESC WCFI data. METHODS: ESC members completed the WCFI standardized survey tool, encompassing 40 questions grouped into 20 factors associated with successful collaboration, annually. LESSONS LEARNED: Community collaborations are naturally slow to establish, with funding/staffing concerns standing out as primary fears within the membership. CONCLUSIONS: Participation in the ESC provided leadership, structure, and concrete goals, which bolstered local collaborative efforts. Overall, the WCFI is proposed as an insightful tool for evaluating community collaboratives.


Assuntos
Pesquisa Participativa Baseada na Comunidade , Liderança , Pré-Escolar , Pesquisa Participativa Baseada na Comunidade/métodos , Humanos , Características de Residência , Inquéritos e Questionários
17.
Med Educ Online ; 27(1): 2057790, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35341472

RESUMO

OBJECTIVE: Health care and health professions education are becoming increasingly global, yet no formal international accrediting body exists for medical education. Among the challenges in developing international standards for medical education is the variation in program models, with some regions offering six-year bachelor's degrees and others, including North America, customarily requiring a bachelor's degree prior to admission to a 4-year graduate-level degree program. This study sought to determine the applicability of the USA Liaison Committee on Medical Education (LCME) accreditation standards internationally as the foundation for program development, quality improvement, and program evaluation in a program that follows the North American medical education model in the United Arab Emirates (UAE). METHODS: Using a qualitative political, economic, sociocultural, technological, legal, and environmental (PESTLE) analysis framework, we systematically assessed the applicability of each of the 93 LCME accreditation elements to the nascent doctor of medicine (MD) degree program at Khalifa University. RESULTS: All 93 elements in the most current LCME accreditation standards were deemed applicable internationally in a program developed in accordance with the North American model of medical education. Of these, three elements were deemed applicable with caveats in the legal or regulatory processes required to achieve comparable compliance outside of the USA. No elements were deemed not applicable in an international setting. CONCLUSIONS: Our analysis demonstrates that the LCME accreditation standards are model-specific and can be effectively applied internationally in programs that follow the North American model of medical education. Countries in which no specialized medical education accrediting body exists can apply the LCME standards and achieve international benchmarks of quality in medical education through rigorous self-assessment and continuous quality improvement.


Assuntos
Acreditação , Educação Médica , Humanos , América do Norte , Melhoria de Qualidade , Emirados Árabes Unidos
18.
Elife ; 112022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35815945

RESUMO

Immunometabolic reprogramming due to adenosine produced by CD73 (encoded by the 5'-ectonucleotidase gene NT5E) is a recognized immunosuppressive mechanism contributing to immune evasion in solid tumors. Adenosine is not only known to contribute to tumor progression, but it has specific roles in driving dysfunction of immune cells, including natural killer (NK) cells. Here, we engineered human NK cells to directly target the CD73-adenosine axis by blocking the enzymatic activity of CD73. In doing so, the engineered NK cells not only impaired adenosinergic metabolism driven by the hypoxic uptake of ATP by cancer cells in a model of non-small-cell lung cancer, but also mediated killing of tumor cells due to the specific recognition of overexpressed CD73. This resulted in a 'single agent' immunotherapy that combines antibody specificity, blockade of purinergic signaling, and killing of targets mediated by NK cells. We also showed that CD73-targeted NK cells are potent in vivo and result in tumor arrest, while promoting NK cell infiltration into CD73+ tumors and enhancing intratumoral activation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adenosina/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Humanos , Imunoterapia/métodos , Células Matadoras Naturais , Neoplasias Pulmonares/metabolismo
19.
Cell Rep ; 40(3): 111128, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858579

RESUMO

Neutrophils, the most abundant white blood cells in circulation, are closely related to cancer development and progression. Healthy primary neutrophils present potent cytotoxicity against various cancer cell lines through direct contact and via generation of reactive oxygen species. However, due to their short half-life and resistance to genetic modification, neutrophils have not yet been engineered with chimeric antigen receptors (CARs) to enhance their antitumor cytotoxicity for targeted immunotherapy. Here, we genetically engineered human pluripotent stem cells with synthetic CARs and differentiated them into functional neutrophils by implementing a chemically defined platform. The resulting CAR neutrophils present superior and specific cytotoxicity against tumor cells both in vitro and in vivo. Collectively, we established a robust platform for massive production of CAR neutrophils, paving the way to myeloid cell-based therapeutic strategies that would boost current cancer-treatment approaches.


Assuntos
Neoplasias , Células-Tronco Pluripotentes , Receptores de Antígenos Quiméricos , Humanos , Imunoterapia , Imunoterapia Adotiva/métodos , Neoplasias/terapia , Neutrófilos/metabolismo , Células-Tronco Pluripotentes/metabolismo , Receptores de Antígenos Quiméricos/metabolismo
20.
Epigenetics ; 17(11): 1513-1534, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35502615

RESUMO

Hepatocellular carcinoma (HCC) is mostly triggered by environmental and life-style factors and may involve epigenetic aberrations. However, a comprehensive documentation of the link between the dysregulated epigenome, transcriptome, and liver carcinogenesis is lacking. In the present study, Fischer-344 rats were fed a choline-deficient (CDAA, cancer group) or choline-sufficient (CSAA, healthy group) L-amino acid-defined diet. At the end of 52 weeks, transcriptomic alterations in livers of rats with HCC tumours and healthy livers were investigated by RNA sequencing. DNA methylation and gene expression were assessed by pyrosequencing and quantitative reverse-transcription PCR (qRT-PCR), respectively. We discovered 1,848 genes that were significantly differentially expressed in livers of rats with HCC tumours (CDAA) as compared with healthy livers (CSAA). Upregulated genes in the CDAA group were associated with cancer-related functions, whereas macronutrient metabolic processes were enriched by downregulated genes. Changes of highest magnitude were detected in numerous upregulated genes that govern key oncogenic signalling pathways, including Notch, Wnt, Hedgehog, and extracellular matrix degradation. We further detected perturbations in DNA methylating and demethylating enzymes, which was reflected in decreased global DNA methylation and increased global DNA hydroxymethylation. Four selected upregulated candidates, Mmp12, Jag1, Wnt4, and Smo, demonstrated promoter hypomethylation with the most profound decrease in Mmp12. MMP12 was also strongly overexpressed and hypomethylated in human HCC HepG2 cells as compared with primary hepatocytes, which coincided with binding of Ten-eleven translocation 1 (TET1). Our findings provide comprehensive evidence for gene expression changes and dysregulated epigenome in HCC pathogenesis, potentially revealing novel targets for HCC prevention/treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Ratos , Aminoácidos/genética , Aminoácidos/metabolismo , Carcinoma Hepatocelular/patologia , Colina , DNA/metabolismo , Metilação de DNA , Epigênese Genética , Expressão Gênica , Neoplasias Hepáticas/metabolismo , Metaloproteinase 12 da Matriz/genética , Metaloproteinase 12 da Matriz/metabolismo , Oxigenases de Função Mista/genética , Proteínas Proto-Oncogênicas/genética , Ratos Endogâmicos F344
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