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2.
Toxins (Basel) ; 16(2)2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38393158

RESUMO

Glioblastoma multiforme (GBM) is the most aggressive type of brain cancer, with a poor prognosis. GBM cells, which develop in the environment of neural tissue, often exploit neurotransmitters and their receptors to promote their own growth and invasion. Nicotinic acetylcholine receptors (nAChRs), which play a crucial role in central nervous system signal transmission, are widely represented in the brain, and GBM cells express several subtypes of nAChRs that are suggested to transmit signals from neurons, promoting tumor invasion and growth. Analysis of published GBM transcriptomes revealed spatial heterogeneity in nAChR subtype expression, and functional nAChRs of α1*, α7, and α9 subtypes are demonstrated in our work on several patient-derived GBM microsphere cultures and on the U87MG GBM cell line using subtype-selective neurotoxins and fluorescent calcium mobilization assay. The U87MG cell line shows reactions to nicotinic agonists similar to those of GBM patient-derived culture. Selective α1*, α7, and α9 nAChR neurotoxins stimulated cell growth in the presence of nicotinic agonists. Several cultivating conditions with varying growth factor content have been proposed and tested. The use of selective neurotoxins confirmed that cell cultures obtained from patients are representative GBM models, but the use of media containing fetal bovine serum can lead to alterations in nAChR expression and functioning.


Assuntos
Glioblastoma , Receptores Nicotínicos , Humanos , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Agonistas Nicotínicos/farmacologia , Proteínas/metabolismo , Peptídeos/farmacologia , Linhagem Celular , Proliferação de Células , Antagonistas Nicotínicos/farmacologia
3.
Int J Biol Macromol ; 255: 128096, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37972835

RESUMO

Destroying tumor vasculature is a relevant therapeutic strategy due to its involvement in tumor progression. However, adaptive resistance to approved antiangiogenic drugs targeting VEGF/VEGFR pathway requires the recruitment of additional targets. In this aspect, targeting TRAIL pathway is promising as it is an important component of the immune system involved in tumor immunosurveillance. For dual targeting of malignant cells and tumor vascular microenvironment, we designed a multivalent fusion protein SRH-DR5-B-iRGD with antiangiogenic VEGFR2-specific peptide SRH at the N-terminus and a tumor-targeting and -penetrating peptide iRGD at the C-terminus of receptor-selective TRAIL variant DR5-B. SRH-DR5-B-iRGD obtained high affinity for DR5, VEGFR2 and αvß3 integrin in nanomolar range. Fusion of DR5-B with effector peptides accelerated DR5 receptor internalization rate upon ligand binding. Antitumor efficacy was evaluated in vitro in human tumor cell lines and primary patient-derived glioblastoma neurospheres, and in vivo in xenograft mouse model of human glioblastoma. Multivalent binding of SRH-DR5-B-iRGD fusion efficiently stimulated DR5-mediated tumor cell death via caspase-dependent mechanism, suppressed xenograft tumor growth by >80 %, doubled the lifespan of xenograft animals, and inhibited tumor vascularization. Therefore, targeting DR5 and VEGFR2 molecular pathways with SRH-DR5-B-iRGD protein may provide a novel therapeutic approach for treatment of solid tumors.


Assuntos
Glioblastoma , Humanos , Animais , Camundongos , Apoptose , Angiogênese , Linhagem Celular Tumoral , Peptídeos , Ensaios Antitumorais Modelo de Xenoenxerto , Microambiente Tumoral
4.
Int J Mol Sci ; 23(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36293545

RESUMO

TRAIL (TNF-related apoptosis-inducing ligand) and its derivatives are potentials for anticancer therapy due to the selective induction of apoptosis in tumor cells upon binding to death receptors DR4 or DR5. Previously, we generated a DR5-selective TRAIL mutant variant DR5-B overcoming receptor-dependent resistance of tumor cells to TRAIL. In the current study, we improved the antitumor activity of DR5-B by fusion with a tumor-homing iRGD peptide, which is known to enhance the drug penetration into tumor tissues. The obtained bispecific fusion protein DR5-B-iRGD exhibited dual affinity for DR5 and integrin αvß3 receptors. DR5-B-iRGD penetrated into U-87 tumor spheroids faster than DR5-B and demonstrated an enhanced antitumor effect in human glioblastoma cell lines T98G and U-87, as well as in primary patient-derived glioblastoma neurospheres in vitro. Additionally, DR5-B-iRGD was highly effective in a xenograft mouse model of the U-87 human glioblastoma cell line in vivo. We suggest that DR5-B-iRGD may become a promising candidate for targeted therapy for glioblastoma.


Assuntos
Glioblastoma , Ligante Indutor de Apoptose Relacionado a TNF , Humanos , Camundongos , Animais , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Integrina alfaVbeta3/genética , Linhagem Celular Tumoral , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Apoptose
5.
Am J Med ; 132(12): 1421-1430.e8, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31228413

RESUMO

BACKGROUND: Delirium is an acute change in mental status affecting 10%-64% of hospitalized patients, and may be preventable in 30%-40% of cases. In October 2013, a task force for delirium prevention and early identification in medical-surgical units was formed at our hospital. We studied whether our standardized protocol prevented delirium among high-risk patients. METHODS: We studied 105,455 patient encounters between November 2013 and January 2018. Since November 2013, there has been ongoing education to decrease deliriogenic medications use. Since 2014, nurses screen all patients for presence or absence of delirium using the Confusion Assessment Method (CAM). Since 2015, nurses additionally screen all patients for risk of delirium. In 2015, a physician order set for delirium was created. Nonpharmacological measures are implemented for high-risk or CAM positive patients. RESULTS: 98.8% of patient encounters had CAM screening, and 99.6% had delirium risk screening. Since 2013, odds of opiate use decreased by 5.0% per year (P < .001), and odds of benzodiazepine use decreased by 8.0% per year (P < .001). There was no change in anticholinergic use. In the adjusted analysis, since 2015, odds of delirium decreased by 25.3% per year among high-risk patients (n = 21,465; P < .001). Among high-risk patients or those diagnosed with delirium (n = 22,121), estimated length of stay decreased by 0.13 days per year (P < .001), odds of inpatient mortality decreased by 16.0% per year (P = .011), and odds of discharge to a nursing home decreased by 17.1% per year (P < .001). CONCLUSION: With high clinician engagement and simplified workflows, our delirium initiative has shown sustained results.


Assuntos
Delírio/epidemiologia , Delírio/prevenção & controle , Diagnóstico Precoce , Unidades de Terapia Intensiva/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Prevenção Primária/organização & administração , Idoso , California/epidemiologia , Estudos de Coortes , Delírio/fisiopatologia , Feminino , Hospitais de Ensino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Complicações Pós-Operatórias/psicologia , Prevalência , Prognóstico , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos , Medição de Risco , Centros de Traumatologia
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