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1.
Nat Commun ; 15(1): 205, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177103

RESUMO

Synapses are pivotal sites of plasticity and memory formation. Consequently, synapses are energy consumption hotspots susceptible to dysfunction when their energy supplies are perturbed. Mitochondria are stabilized near synapses via the cytoskeleton and provide the local energy required for synaptic plasticity. However, the mechanisms that tether and stabilize mitochondria to support synaptic plasticity are unknown. We identified proteins exclusively tethering mitochondria to actin near postsynaptic spines. We find that VAP, the vesicle-associated membrane protein-associated protein implicated in amyotrophic lateral sclerosis, stabilizes mitochondria via actin near the spines. To test if the VAP-dependent stable mitochondrial compartments can locally support synaptic plasticity, we used two-photon glutamate uncaging for spine plasticity induction and investigated the induced and adjacent uninduced spines. We find VAP functions as a spatial stabilizer of mitochondrial compartments for up to ~60 min and as a spatial ruler determining the ~30 µm dendritic segment supported during synaptic plasticity.


Assuntos
Actinas , Espinhas Dendríticas , Actinas/metabolismo , Espinhas Dendríticas/metabolismo , Plasticidade Neuronal , Sinapses/metabolismo , Mitocôndrias/metabolismo
2.
Ther Adv Med Oncol ; 15: 17588359231210675, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38028143

RESUMO

Prognosis of metastatic triple negative breast cancer (mTNBC) remains poor despite recent advances in therapeutic options. Trastuzumab deruxtecan (T-DXd) has shown promising efficacy in patients with human epidermal growth factor receptor 2 (HER2)-low breast cancer, which is defined by immunohistochemistry (IHC) 1+ or 2+ and lack of HER2 amplification by fluorescence in situ hybridization (FISH) testing. The purpose of the study is to evaluate the safety and initial evidence of efficacy of intratumoral administration of CF33-hNIS-anti-PD-L1 (CHECKvacc) against mTNBC. Oncolytic virus CHECKvacc intratumoral injection is currently undergoing investigation in patients with mTNBC as a single agent (NCT05081492). The patient was enrolled on the clinical trial CHECKvacc for the Treatment of Metastatic Triple Negative Breast Cancer, received a single dose of CHECKvacc, and discontinued the study due to lack of immediate response. We report a case of a patient with mTNBC who was heavily pretreated and presented with extensive dermal metastasis. Two dermal metastasis biopsies in 2021 showed HER2 0 by IHC. The patient received a single dose of CHECKvacc and discontinued the study due to lack of immediate response. Twenty-five days later, the patient received treatment with T-DXd, and her tumor regressed significantly. The patient's disease-free survival was 10 months (December 2021-October 2022). The sequential treatment with intratumoral injection of CHECKvacc followed by T-DXd may have significant clinical activity in select patients with heavily pretreated mTNBC. ClinicalTrials.gov NCT05081492.

3.
Biochemistry ; 50(20): 4330-6, 2011 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-21510682

RESUMO

Tau filaments are the pathological hallmark of >20 neurodegenerative diseases including Alzheimer's disease. Six tau isoforms exist that can be grouped into 4-repeat (4R) tau and 3-repeat (3R) tau based on the presence or absence of the second of four microtubule binding repeats. Recent evidence suggests that tau filaments can transfer between cells and spread through the brain. Here we demonstrate in vitro that seeded filament growth, a prerequisite for tau spreading, is crucially dependent on the isoform composition of individual seeds. Seeds of 3R tau and 3R/4R tau recruit both types of isoforms. Seeds of 4R tau recruit 4R tau, but not 3R tau, establishing an asymmetric barrier. Conformational templating of 4R tau onto 3R tau seeds eliminates this barrier, giving rise to a new type of tau filament. These findings provide fundamental mechanistic insights into the seeding, propagation, and diversification of tau filaments.


Assuntos
Multimerização Proteica , Estrutura Quaternária de Proteína , Sequências Repetitivas de Aminoácidos , Proteínas tau/química
4.
Clin Cancer Res ; 26(7): 1595-1605, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31831558

RESUMO

PURPOSE: To evaluate the safety and feasibility of preoperative locoregional cytokine therapy (IRX-2 regimen) in early-stage breast cancer, and to evaluate for intratumoral and peripheral immunomodulatory activity. PATIENTS AND METHODS: Sixteen patients with stage I-III early-stage breast cancer (any histology type) indicated for surgical lumpectomy or mastectomy were enrolled to receive preoperative locoregional immunotherapy with the IRX-2 cytokine biological (2 mL subcutaneous × 10 days to periareolar skin). The regimen also included single-dose cyclophosphamide (300 mg/m2) on day 1 to deplete T-regulatory cells and oral indomethacin to modulate suppressive myeloid subpopulations. The primary objective was to evaluate feasibility (i.e., receipt of therapy without surgical delays or grade 3/4 treatment-related adverse events). The secondary objective was to evaluate changes in stromal tumor-infiltrating lymphocyte score. The exploratory objective was to identify candidate pharmacodynamic changes for future study using a variety of assays, including flow cytometry, RNA and T-cell receptor DNA sequencing, and multispectral immunofluorescence. RESULTS: Preoperative locoregional cytokine administration was feasible in 100% (n = 16/16) of subjects and associated with increases in stromal tumor-infiltrating lymphocytes (P < 0.001). Programmed death ligand 1 (CD274) was upregulated at the RNA (P < 0.01) and protein level [by Ventana PD-L1 (SP142) and immunofluorescence]. Other immunomodulatory effects included upregulation of RNA signatures of T-cell activation and recruitment and cyclophosphamide-related peripheral T-regulatory cell depletion. CONCLUSIONS: IRX-2 is safe in early-stage breast cancer. Potentially favorable immunomodulatory changes were observed, supporting further study of IRX-2 in early-stage breast cancer and other malignancies.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias da Mama/terapia , Citocinas/uso terapêutico , Imunidade/efeitos dos fármacos , Imunoterapia/métodos , Linfócitos do Interstício Tumoral/imunologia , Cuidados Pré-Operatórios , Idoso , Antígeno B7-H1/imunologia , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Segurança do Paciente , Projetos Piloto , Resultado do Tratamento
5.
Oncotarget ; 7(33): 53881-53894, 2016 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-27449089

RESUMO

Checkpoint kinase 1 (CHK1) is an integral component of the cell cycle as well as the DNA Damage Response (DDR) pathway. Previous work has demonstrated the effectiveness of inhibiting CHK1 with small-molecule inhibitors, but the role of CHK1 mediated DDR in medulloblastoma is unknown. CHK1, both at the mRNA and protein level, is highly expressed in medulloblastoma and elevated CHK1 expression in Group3 medulloblastoma is an adverse prognostic marker. CHK1 inhibition with the small-molecule drug AZD7762, results in decreased cell growth, increased DNA damage and cell apoptosis. Furthermore, AZD7762 acts in synergy with cisplatin in reducing cell proliferation in medulloblastoma. Similar phenotypic changes were observed with another CHK1 inhibitor, PF477736, as well as genetic knockdown using siRNA against CHK1. Treatments with small-molecule inhibitors of CHK1 profoundly modulated the expression of both upstream and downstream target proteins within the CHK1 signaling pathways. This suggests the presence of a feedback loop in activating CHK1. Overall, our results demonstrate that small-molecule inhibition of CHK1 in combination with, cisplatin, is more advantageous than either treatment alone, especially for Group 3 medulloblastoma, and therefore this combined therapeutic approach serves as an avenue for further investigation.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Cerebelares/patologia , Quinase 1 do Ponto de Checagem/biossíntese , Meduloblastoma/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Benzodiazepinonas/farmacologia , Biomarcadores Tumorais/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Cerebelares/enzimologia , Neoplasias Cerebelares/mortalidade , Cisplatino/farmacologia , Intervalo Livre de Doença , Genes myc , Humanos , Estimativa de Kaplan-Meier , Meduloblastoma/enzimologia , Meduloblastoma/mortalidade , Prognóstico , Pirazóis/farmacologia , Tiofenos/farmacologia , Ureia/análogos & derivados , Ureia/farmacologia
6.
Indian J Pediatr ; 81(7): 655-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24553973

RESUMO

OBJECTIVES: To compare the efficacy of oral Montelukast and inhaled Budesonide as a first line preventive therapy in mild persistent asthma in age group 2-18 y. METHODS: This prospective randomized controlled clinical study was conducted for 12 wk. Sixty patients of mild persistent asthma aged 2 to 18 y were randomly allocated to either oral Montelukast (n = 60) or inhaled Budesonide (n = 60) group. Outcomes measured were improvement in peak expiratory flow rate (PEFR), forced expiratory volume 1 s/forced vital capacity (FEV1/FVC), day time and night time symptoms and frequency of exacerbations and need to change medications. RESULTS: There was significant improvement in PEFR, FEV1/FVC, day time and night time symptoms and frequency of exacerbations in both groups. However, more significant improvement in FEV1/FVC (CI 95 %, p = 0.029) and day time symptoms (CI 95 %, p = 0.002) was seen in Budesonide group compared to Montelukast group. CONCLUSIONS: The present study suggests that oral Montelukast is not inferior to Budesonide in treatment of mild persistent asthma in 2 to 18 y children in terms of control of symptoms and improvement in pulmonary function tests over a 12 wk period. However, there was more significant improvement in day time symptoms, more significant increase in FEV1/FVC ratio and less exacerbation in patients receiving Budesonide compared to those receiving Montelukast. However, side effects due to long term use of steroids such as growth stunting and bone osteopenia should also be considered before recommending. Trial registered at CTRI no. REF/2012/09/004035.


Assuntos
Acetatos/uso terapêutico , Antiasmáticos/uso terapêutico , Asma/prevenção & controle , Broncodilatadores/uso terapêutico , Budesonida/uso terapêutico , Quinolinas/uso terapêutico , Adolescente , Criança , Pré-Escolar , Ciclopropanos , Feminino , Humanos , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença , Sulfetos
7.
World J Gastroenterol ; 19(34): 5645-50, 2013 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-24039356

RESUMO

AIM: To investigate the quality of topical 2% diltiazem formulations extemporaneously compounded by retail pharmacies openly offering drug-compounding services. METHODS: A participating healthcare professional wrote 12 prescriptions for compounded 2% diltiazem cream, with 2 refills allowed per prescription. The 12 sets of prescriptions were filled, at intervals of 1-2 wk between refills, at 12 different independent retail pharmacies that openly offer drug-compounding services in a major metropolitan region. The 36 resultant preparations, provided as jars or tubes, were shipped, as soon as each was filled, at ambient temperature to the study core laboratory for high-performance liquid chromatography (HPLC) analysis, within 10 d of receipt. For the HPLC analysis, 8 different samples of the topical diltiazem, each approximately 1 g in weight, were taken from prespecified locations within each container. To initiate the HPLC analysis, each sample was transferred to a 100 mL volumetric flask, to which methanol was added. The HPLC analysis was conducted in accordance with the laboratory-validated method for diltiazem in cream, ointment, and gel formulations. The main outcome measures were potency (percentage of label claim) and content uniformity of the compounded topical 2% diltiazem formulations. RESULTS: Of the 36 prescriptions filled, 30 were packaged in jars and 6 were packaged as tubes. The prescriptions were specifically for cream formulations, but 6 of the 12 pharmacies compounded 2% diltiazem as an ointment; for another pharmacy, which had inadequate labeling, the dosage form was unknown. The United States Pharmacopoeia (USP) standard for potency is 90%-115% of label claim. Of the 36 preparations, 5 (13.89%) were suprapotent and 13 (36.11%) were subpotent. The suprapotent prescriptions ranged in potency from 117.2% to 128.5% of label claim, and the subpotent prescriptions ranged in potency from 34.8% to 89.8% of label claim. Fourteen (38.9%) preparations lacked content uniformity according to the USP standard of 90%-110% potency and < 6% relative standard deviation. Of the 30 formulations packaged in jars, 12 (40%) lacked content uniformity, while of the 6 formulations packaged in tubes, 2 (33.3%) lacked content uniformity. Nine of the 12 pharmacies (75%) failed USP potency or content-uniformity specifications for at least 1 of the 3 prescription fills. For 5 of the 12 pharmacies (41.7%), the mean potency across all three prescription fills was < 90% of label claim. CONCLUSION: Patients prescribed topical 2% diltiazem for treatment of anal fissure frequently receive compounded formulations that are misbranded with respect to potency and that lack content uniformity.


Assuntos
Bloqueadores dos Canais de Cálcio/normas , Diltiazem/normas , Composição de Medicamentos/normas , Fissura Anal/tratamento farmacológico , Farmácia/normas , Administração Tópica , Bloqueadores dos Canais de Cálcio/uso terapêutico , Cromatografia Líquida de Alta Pressão , Diltiazem/uso terapêutico , Humanos
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