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1.
Neurobiol Dis ; 149: 105228, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33359139

RESUMO

Disruption in copper homeostasis causes a number of cognitive and motor deficits. Wilson's disease and Menkes disease are neurodevelopmental disorders resulting from mutations in the copper transporters ATP7A and ATP7B, with ATP7A mutations also causing occipital horn syndrome, and distal motor neuropathy. A 65 year old male presenting with brachial amyotrophic diplegia and diagnosed with amyotrophic lateral sclerosis (ALS) was found to harbor a p.Met1311Val (M1311V) substitution variant in ATP7A. ALS is a fatal neurodegenerative disease associated with progressive muscle weakness, synaptic deficits and degeneration of upper and lower motor neurons. To investigate the potential contribution of the ATP7AM1311V variant to neurodegeneration, we obtained and characterized both patient-derived fibroblasts and patient-derived induced pluripotent stem cells differentiated into motor neurons (iPSC-MNs), and compared them to control cell lines. We found reduced localization of ATP7AM1311V to the trans-Golgi network (TGN) at basal copper levels in patient-derived fibroblasts and iPSC-MNs. In addition, redistribution of ATP7AM1311V out of the TGN in response to increased extracellular copper was defective in patient fibroblasts. This manifested in enhanced intracellular copper accumulation and reduced survival of ATP7AM1311V fibroblasts. iPSC-MNs harboring the ATP7AM1311V variant showed decreased dendritic complexity, aberrant spontaneous firing, and decreased survival. Finally, expression of the ATP7AM1311V variant in Drosophila motor neurons resulted in motor deficits. Apilimod, a drug that targets vesicular transport and recently shown to enhance survival of C9orf72-ALS/FTD iPSC-MNs, also increased survival of ATP7AM1311V iPSC-MNs and reduced motor deficits in Drosophila expressing ATP7AM1311V. Taken together, these observations suggest that ATP7AM1311V negatively impacts its role as a copper transporter and impairs several aspects of motor neuron function and morphology.


Assuntos
ATPases Transportadoras de Cobre/genética , ATPases Transportadoras de Cobre/metabolismo , Cobre/metabolismo , Variação Genética/fisiologia , Doença dos Neurônios Motores/genética , Doença dos Neurônios Motores/metabolismo , Animais , Animais Geneticamente Modificados , Animais Recém-Nascidos , Células Cultivadas , Cobre/farmacologia , Cobre/uso terapêutico , Relação Dose-Resposta a Droga , Drosophila , Variação Genética/efeitos dos fármacos , Células HeLa , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , Doença dos Neurônios Motores/tratamento farmacológico , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia
3.
Acta Neuropathol ; 138(1): 49-65, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30945056

RESUMO

The hexanucleotide repeat expansion GGGGCC (G4C2)n in the C9orf72 gene is the most common genetic abnormality associated with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Recent findings suggest that dysfunction of nuclear-cytoplasmic trafficking could affect the transport of RNA binding proteins in C9orf72 ALS/FTD. Here, we provide evidence that the RNA editing enzyme adenosine deaminase acting on RNA 2 (ADAR2) is mislocalized in C9orf72 repeat expansion mediated ALS/FTD. ADAR2 is responsible for adenosine (A) to inosine (I) editing of double-stranded RNA, and its function has been shown to be essential for survival. Here we show the mislocalization of ADAR2 in human induced pluripotent stem cell-derived motor neurons (hiPSC-MNs) from C9orf72 patients, in mice expressing (G4C2)149, and in C9orf72 ALS/FTD patient postmortem tissue. As a consequence of this mislocalization we observe alterations in RNA editing in our model systems and across multiple brain regions. Analysis of editing at 408,580 known RNA editing sites indicates that there are vast RNA A to I editing aberrations in C9orf72-mediated ALS/FTD. These RNA editing aberrations are found in many cellular pathways, such as the ALS pathway and the crucial EIF2 signaling pathway. Our findings suggest that the mislocalization of ADAR2 in C9orf72 mediated ALS/FTD is responsible for the alteration of RNA processing events that may impact vast cellular functions, including the integrated stress response (ISR) and protein translation.


Assuntos
Adenosina Desaminase/genética , Proteína C9orf72/genética , Edição de RNA/genética , Proteínas de Ligação a RNA/genética , Esclerose Lateral Amiotrófica/genética , Animais , Expansão das Repetições de DNA/genética , Demência Frontotemporal/genética , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos Transgênicos , Doença de Pick/genética
4.
Breast Cancer Res ; 17: 41, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25886996

RESUMO

INTRODUCTION: Accurate assessment of HER2 status is critical in determining appropriate therapy for breast cancer patients but the best HER2 testing methodology has yet to be defined. In this study, we compared quantitative HER2 expression by the HERmark™ Breast Cancer Assay (HERmark) with routine HER2 testing by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH), and correlated HER2 results with overall survival (OS) of breast cancer patients in a multicenter Collaborative Biomarker Study (CBS). METHODS: Two hundred and thirty-two formalin-fixed, paraffin-embedded breast cancer tissues and local laboratory HER2 testing results were provided by 11 CBS sites. HERmark assay and central laboratory HER2 IHC retesting were retrospectively performed in a blinded fashion. HER2 results by all testing methods were obtained in 192 cases. RESULTS: HERmark yielded a continuum of total HER2 expression (H2T) ranging from 0.3 to 403 RF/mm2 (approximately 3 logs). The distribution of H2T levels correlated significantly (P<0.0001) with all routine HER2 testing results. The concordance of positive and negative values (equivocal cases excluded) between HERmark and routine HER2 testing was 84% for local IHC, 96% for central IHC, 85% for local FISH, and 84% for local HER2 status. OS analysis revealed a significant correlation of shorter OS with HER2 positivity by local IHC (HR=2.6, P=0.016), central IHC (HR=3.2, P=0.015), and HERmark (HR=5.1, P<0.0001) in this cohort of patients most of whom received no HER2-targeted therapy. The OS curve of discordant low (HER2 positive but H2T low, 10% of all cases) was aligned with concordant negative (HER2 negative and H2T low, HR=1.9, P=0.444), but showed a significantly longer OS than concordant positive (HER2 positive and H2T high, HR=0.31, P=0.024). Conversely, the OS curve of discordant high (HER2 negative but H2T high, 9% of all cases) was aligned with concordant positive (HR=0.41, P=0.105), but showed a significantly shorter OS than concordant negative (HR=41, P<0.0001). CONCLUSIONS: Quantitative HER2 measurement by HERmark is highly sensitive, accurately quantifies HER2 protein expression and correlates well with routine HER2 testing. When HERmark and local HER2 results were discordant, HERmark more accurately predicted overall survival.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Feminino , Seguimentos , Humanos , Imuno-Histoquímica/métodos , Hibridização in Situ Fluorescente/métodos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Carga Tumoral , Adulto Jovem
5.
Elife ; 122024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38358392

RESUMO

Although gene expression divergence has long been postulated to be the primary driver of human evolution, identifying the genes and genetic variants underlying uniquely human traits has proven to be quite challenging. Theory suggests that cell-type-specific cis-regulatory variants may fuel evolutionary adaptation due to the specificity of their effects. These variants can precisely tune the expression of a single gene in a single cell-type, avoiding the potentially deleterious consequences of trans-acting changes and non-cell type-specific changes that can impact many genes and cell types, respectively. It has recently become possible to quantify human-specific cis-acting regulatory divergence by measuring allele-specific expression in human-chimpanzee hybrid cells-the product of fusing induced pluripotent stem (iPS) cells of each species in vitro. However, these cis-regulatory changes have only been explored in a limited number of cell types. Here, we quantify human-chimpanzee cis-regulatory divergence in gene expression and chromatin accessibility across six cell types, enabling the identification of highly cell-type-specific cis-regulatory changes. We find that cell-type-specific genes and regulatory elements evolve faster than those shared across cell types, suggesting an important role for genes with cell-type-specific expression in human evolution. Furthermore, we identify several instances of lineage-specific natural selection that may have played key roles in specific cell types, such as coordinated changes in the cis-regulation of dozens of genes involved in neuronal firing in motor neurons. Finally, using novel metrics and a machine learning model, we identify genetic variants that likely alter chromatin accessibility and transcription factor binding, leading to neuron-specific changes in the expression of the neurodevelopmentally important genes FABP7 and GAD1. Overall, our results demonstrate that integrative analysis of cis-regulatory divergence in chromatin accessibility and gene expression across cell types is a promising approach to identify the specific genes and genetic variants that make us human.


Assuntos
Cromatina , Pan troglodytes , Humanos , Animais , Cromatina/genética , Células Híbridas , Neurônios Motores , Expressão Gênica
6.
bioRxiv ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38798687

RESUMO

Chimeras have played a foundational role in biology, for example by enabling the classification of developmental processes into those driven intrinsically by individual cells versus those driven extrinsically by their extracellular environment. Here, we extend this framework to decompose evolutionary divergence in gene expression and other quantitative traits into cell-intrinsic, extrinsic, and intrinsic-extrinsic interaction components. Applying this framework to reciprocal rat-mouse chimeras, we found that the majority of gene expression divergence is attributable to cell-intrinsic factors, though extrinsic factors also play an integral role. For example, a rat-like extracellular environment extrinsically up-regulates the expression of a key transcriptional regulator of the endoplasmic reticulum (ER) stress response in some but not all cell types, which in turn strongly predicts extrinsic up-regulation of its target genes and of the ER stress response pathway as a whole. This effect is also seen at the protein level, suggesting propagation through multiple regulatory levels. We also demonstrate that our framework is applicable to a cellular trait, neuronal differentiation, and estimated the intrinsic and extrinsic contributions to its divergence. Finally, we show that imprinted genes are dramatically mis-expressed in species-mismatched environments, suggesting that mismatch between rapidly evolving intrinsic and extrinsic mechanisms controlling gene imprinting may contribute to barriers to interspecies chimerism. Overall, our conceptual framework opens new avenues to investigate the mechanistic basis of evolutionary divergence in gene expression and other quantitative traits in any multicellular organism.

7.
Genome Biol ; 24(1): 11, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658652

RESUMO

Measuring allele-specific expression in interspecies hybrids is a powerful way to detect cis-regulatory changes underlying adaptation. However, it remains difficult to identify genes most likely to explain species-specific traits. Here, we outline a simple strategy that leverages population-scale allele-specific RNA-seq data to identify genes that show constrained cis-regulation within species yet show divergence between species. Applying this strategy to data from human-chimpanzee hybrid cortical organoids, we identify signatures of lineage-specific selection on genes related to saccharide metabolism, neurodegeneration, and primary cilia. We also highlight cis-regulatory divergence in CUX1 and EDNRB that may shape the trajectory of human brain development.


Assuntos
Evolução Molecular , Organoides , Humanos , Alelos , Pan troglodytes , Animais
8.
bioRxiv ; 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37292820

RESUMO

Although gene expression divergence has long been postulated to be the primary driver of human evolution, identifying the genes and genetic variants underlying uniquely human traits has proven to be quite challenging. Theory suggests that cell type-specific cis-regulatory variants may fuel evolutionary adaptation due to the specificity of their effects. These variants can precisely tune the expression of a single gene in a single cell type, avoiding the potentially deleterious consequences of trans-acting changes and non-cell type-specific changes that can impact many genes and cell types, respectively. It has recently become possible to quantify human-specific cis-acting regulatory divergence by measuring allele-specific expression in human-chimpanzee hybrid cells-the product of fusing induced pluripotent stem (iPS) cells of each species in vitro. However, these cis-regulatory changes have only been explored in a limited number of cell types. Here, we quantify human-chimpanzee cis-regulatory divergence in gene expression and chromatin accessibility across six cell types, enabling the identification of highly cell type-specific cis-regulatory changes. We find that cell type-specific genes and regulatory elements evolve faster than those shared across cell types, suggesting an important role for genes with cell type-specific expression in human evolution. Furthermore, we identify several instances of lineage-specific natural selection that may have played key roles in specific cell types, such as coordinated changes in the cis-regulation of dozens of genes involved in neuronal firing in motor neurons. Finally, using novel metrics and a machine learning model, we identify genetic variants that likely alter chromatin accessibility and transcription factor binding, leading to neuron-specific changes in the expression of the neurodevelopmentally important genes FABP7 and GAD1. Overall, our results demonstrate that integrative analysis of cis-regulatory divergence in chromatin accessibility and gene expression across cell types is a promising approach to identify the specific genes and genetic variants that make us human.

9.
Front Mol Neurosci ; 16: 1353562, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38348237

RESUMO

The central nervous system encounters a number of challenges following HIV infection, leading to increased risk for a collection of neurocognitive symptoms clinically classified as HIV-associated neurocognitive disorders (HAND). Studies attempting to identify causal mechanisms and potential therapeutic interventions have historically relied on primary rodent neurons, but a number of recent reports take advantage of iPSC-derived neurons in order to study these mechanisms in a readily reproducible, human model. We found that iPSC-derived neurons differentiated via an inducible neurogenin-2 transcription factor were resistant to gross toxicity from a number of HIV-associated insults previously reported to be toxic in rodent models, including HIV-infected myeloid cell supernatants and the integrase inhibitor antiretroviral drug, elvitegravir. Further examination of these cultures revealed robust resistance to NMDA receptor-mediated toxicity. We then performed a comparative analysis of iPSC neurons exposed to integrase inhibitors and activated microglial supernatants to study sub-cytotoxic alterations in micro electrode array (MEA)-measured neuronal activity and gene expression, identifying extracellular matrix interaction/morphogenesis as the most consistently altered pathways across HIV-associated insults. These findings illustrate that HIV-associated insults dysregulate human neuronal activity and organization even in the absence of gross NMDA-mediated neurotoxicity, which has important implications on the effects of these insults in neurodevelopment and on the interpretation of primary vs. iPSC in vitro neuronal studies.

10.
Viruses ; 13(7)2021 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206839

RESUMO

The persistence of human immunodeficiency virus-1 (HIV)-associated neurocognitive disorders (HAND) in the era of effective antiretroviral therapy suggests that modern HIV neuropathogenesis is driven, at least in part, by mechanisms distinct from the viral life cycle. Identifying more subtle mechanisms is complicated by frequent comorbidities in HIV+ populations. One of the common confounds is substance abuse, with cannabis being the most frequently used psychoactive substance among people living with HIV. The psychoactive effects of cannabis use can themselves mimic, and perhaps magnify, the cognitive deficits observed in HAND; however, the neuromodulatory and anti-inflammatory properties of cannabinoids may counter HIV-induced excitotoxicity and neuroinflammation. Here, we review our understanding of the cross talk between HIV and cannabinoids in the central nervous system by exploring both clinical observations and evidence from preclinical in vivo and in vitro models. Additionally, we comment on recent advances in human, multi-cell in vitro systems that allow for more translatable, mechanistic studies of the relationship between cannabinoid pharmacology and this uniquely human virus.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Canabinoides/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/terapia , HIV-1/efeitos dos fármacos , Doenças Neuroinflamatórias/terapia , Animais , Fármacos Anti-HIV/farmacologia , Canabinoides/farmacologia , Canabinoides/normas , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Humanos , Técnicas In Vitro , Camundongos , Psicotrópicos/farmacologia , Psicotrópicos/normas , Psicotrópicos/uso terapêutico
11.
Food Funct ; 12(17): 8068-8077, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34286798

RESUMO

BACKGROUND AND OBJECTIVE: While there are multiple studies on the anti-tumoral effects of Panax ginseng as active ingredients (one or more ginsenosides derived from the extract) or as a whole plant extract, there is a lack of studies to assess the effects Panax ginseng's of active ingredients combined with the whole plant extract. Our aim was to study the effect of whole ginseng, enriched in the anti-tumoral Rh2 component and other ginsenosides (Ginseng Rh2+), on the metastatic capacity of non-small cell lung cancer (NSCLC). METHODS: We evaluated the effects of Ginseng Rh2+ on survival, migration and motility, induction of apoptosis, and expression of its apoptosis-related proteins in non-small cell lung cancer (NSCLC) cells in vitro and on primary tumor growth and metastatic capacity in a syngeneic mouse lung cancer model in vivo. The effects of Ginseng Rh2+ on NSCLC cells were studied in vitro using: a colorimetric tetrazolium salt (XTT) assay, annexin V-FITC/PI, western blotting, wound healing motility assay, Transwell migration and cell adhesion assays. In vivo, mice were inoculated with Lewis mouse lung carcinoma cells subcutaneously to evaluate local tumor growth, or intravenously to evaluate the effects of Ginseng Rh2+ on development of experimental metastases. Mice were treated by intraperitoneal administration of Ginseng Rh2+ (0.005-0.5 g kg-1) on days 6, 10, and 14 after tumor injection. RESULTS: We found that Ginseng Rh2+ increased the apoptosis of NSCLC cells in vitro, demonstrating dose dependent down-regulation of the Bcl-2 anti-apoptotic gene and concurrent up-regulation of the Bax pro-apoptotic gene. Ginseng Rh2+ inhibited the tumor cells' capacity to attach to the ECM-related matrix and reduced cell migration. In vivo, Ginseng Rh2+ inhibited local tumor growth and reduced the development of experimental lung metastases. CONCLUSION: Our study suggests that Ginseng Rh2+ may potentially be used as a therapeutic agent for treatment of NSCLC.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Ginsenosídeos/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Panax/química , Extratos Vegetais/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/fisiopatologia , Camundongos , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
12.
Elife ; 82019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-31180318

RESUMO

Amyotrophic Lateral Sclerosis (ALS), is a fatal neurodegenerative disorder, with TDP-43 inclusions as a major pathological hallmark. Using a Drosophila model of TDP-43 proteinopathy we found significant alterations in glucose metabolism including increased pyruvate, suggesting that modulating glycolysis may be neuroprotective. Indeed, a high sugar diet improves locomotor and lifespan defects caused by TDP-43 proteinopathy in motor neurons or glia, but not muscle, suggesting that metabolic dysregulation occurs in the nervous system. Overexpressing human glucose transporter GLUT-3 in motor neurons mitigates TDP-43 dependent defects in synaptic vesicle recycling and improves locomotion. Furthermore, PFK mRNA, a key indicator of glycolysis, is upregulated in flies and patient derived iPSC motor neurons with TDP-43 pathology. Surprisingly, PFK overexpression rescues TDP-43 induced locomotor deficits. These findings from multiple ALS models show that mechanistically, glycolysis is upregulated in degenerating motor neurons as a compensatory mechanism and suggest that increased glucose availability is protective.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Modelos Animais de Doenças , Glucose/metabolismo , Glicólise , Neurônios Motores/metabolismo , Regulação para Cima , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Transportador de Glucose Tipo 3/genética , Transportador de Glucose Tipo 3/metabolismo , Humanos , Neuroproteção/genética , Ácido Pirúvico/metabolismo , Ativação Transcricional
13.
Brain Res ; 1693(Pt A): 98-108, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29453960

RESUMO

Amyotrophic lateral sclerosis (ALS) is characterized by a progressive degeneration of upper and lower motor neurons, resulting in fatal paralysis due to denervation of the muscle. Due to genetic, pathological and symptomatic overlap, ALS is now considered a spectrum disease together with frontotemporal dementia (FTD), the second most common cause of dementia in individuals under the age of 65. Interestingly, in both diseases, there is a large prevalence of RNA binding proteins (RBPs) that are mutated and considered disease-causing, or whose dysfunction contribute to disease pathogenesis. The most common shared genetic mutation in ALS/FTD is a hexanucleuotide repeat expansion within intron 1 of C9ORF72 (C9). Three potentially overlapping, putative toxic mechanisms have been proposed: loss of function due to haploinsufficient expression of the C9ORF72 mRNA, gain of function of the repeat RNA aggregates, or RNA foci, and repeat-associated non-ATG-initiated translation (RAN) of the repeat RNA into toxic dipeptide repeats (DPRs). Regardless of the causative mechanism, disease symptoms are ultimately caused by a failure of neurotransmission in three regions: the brain, the spinal cord, and the neuromuscular junction. Here, we review C9 ALS/FTD-associated synaptic dysfunction and aberrant neuronal excitability in these three key regions, focusing on changes in morphology and synapse formation, excitability, and excitotoxicity in patients, animal models, and in vitro models. We compare these deficits to those seen in other forms of ALS and FTD in search of shared pathways, and discuss the potential targeting of synaptic dysfunctions for therapeutic intervention in ALS and FTD patients.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/genética , Demência Frontotemporal/genética , Sinapses/patologia , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Proteína C9orf72/metabolismo , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Humanos , Neurônios Motores/metabolismo , Mutação , RNA/genética , RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/fisiologia , Sinapses/metabolismo
14.
Front Neurosci ; 12: 56, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29479303

RESUMO

Neurological diseases, including dementias such as Alzheimer's disease (AD) and fronto-temporal dementia (FTD) and degenerative motor neuron diseases such as amyotrophic lateral sclerosis (ALS), are responsible for an increasing fraction of worldwide fatalities. Researching these heterogeneous diseases requires models that endogenously express the full array of genetic and epigenetic factors which may influence disease development in both familial and sporadic patients. Here, we discuss the two primary methods of developing patient-derived neurons and glia to model neurodegenerative disease: reprogramming somatic cells into induced pluripotent stem cells (iPSCs), which are differentiated into neurons or glial cells, or directly converting (DC) somatic cells into neurons (iNeurons) or glial cells. Distinct differentiation techniques for both models result in a variety of neuronal and glial cell types, which have been successful in displaying unique hallmarks of a variety of neurological diseases. Yield, length of differentiation, ease of genetic manipulation, expression of cell-specific markers, and recapitulation of disease pathogenesis are presented as determining factors in how these methods may be used separately or together to ascertain mechanisms of disease and identify therapeutics for distinct patient populations or for specific individuals in personalized medicine projects.

15.
Cell Rep ; 21(1): 110-125, 2017 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-28978466

RESUMO

Amyotrophic lateral sclerosis (ALS) is a synaptopathy accompanied by the presence of cytoplasmic aggregates containing TDP-43, an RNA-binding protein linked to ∼97% of ALS cases. Using a Drosophila model of ALS, we show that TDP-43 overexpression (OE) in motor neurons results in decreased expression of the Hsc70-4 chaperone at the neuromuscular junction (NMJ). Mechanistically, mutant TDP-43 sequesters hsc70-4 mRNA and impairs its translation. Expression of the Hsc70-4 ortholog, HSPA8, is also reduced in primary motor neurons and NMJs of mice expressing mutant TDP-43. Electrophysiology, imaging, and genetic interaction experiments reveal TDP-43-dependent defects in synaptic vesicle endocytosis. These deficits can be partially restored by OE of Hsc70-4, cysteine-string protein (Csp), or dynamin. This suggests that TDP-43 toxicity results in part from impaired activity of the synaptic CSP/Hsc70 chaperone complex impacting dynamin function. Finally, Hsc70-4/HSPA8 expression is also post-transcriptionally reduced in fly and human induced pluripotent stem cell (iPSC) C9orf72 models, suggesting a common disease pathomechanism.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteínas de Ligação a DNA/genética , Proteínas de Choque Térmico HSC70/genética , RNA Mensageiro/genética , Vesículas Sinápticas/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Dinaminas/genética , Dinaminas/metabolismo , Endocitose , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSC70/metabolismo , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP40/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Junção Neuromuscular/metabolismo , Junção Neuromuscular/patologia , Agregados Proteicos , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Transdução de Sinais , Transmissão Sináptica , Vesículas Sinápticas/patologia
16.
Clin Cancer Res ; 19(10): 2745-54, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23444220

RESUMO

PURPOSE: We assessed adding the multikinase inhibitor sorafenib to gemcitabine or capecitabine in patients with advanced breast cancer whose disease progressed during/after bevacizumab. EXPERIMENTAL DESIGN: This double-blind, randomized, placebo-controlled phase IIb study (ClinicalTrials.gov NCT00493636) enrolled patients with locally advanced or metastatic human epidermal growth factor receptor 2 (HER2)-negative breast cancer and prior bevacizumab treatment. Patients were randomized to chemotherapy with sorafenib (400 mg, twice daily) or matching placebo. Initially, chemotherapy was gemcitabine (1,000 mg/m(2) i.v., days 1, 8/21), but later, capecitabine (1,000 mg/m(2) orally twice daily, days 1-14/21) was allowed as an alternative. The primary endpoint was progression-free survival (PFS). RESULTS: One hundred and sixty patients were randomized. More patients received gemcitabine (82.5%) than capecitabine (17.5%). Sorafenib plus gemcitabine/capecitabine was associated with a statistically significant prolongation in PFS versus placebo plus gemcitabine/capecitabine [3.4 vs. 2.7 months; HR = 0.65; 95% confidence interval (CI): 0.45-0.95; P = 0.02], time to progression was increased (median, 3.6 vs. 2.7 months; HR = 0.64; 95% CI: 0.44-0.93; P = 0.02), and overall response rate was 19.8% versus 12.7% (P = 0.23). Median survival was 13.4 versus 11.4 months for sorafenib versus placebo (HR = 1.01; 95% CI: 0.71-1.44; P = 0.95). Addition of sorafenib versus placebo increased grade 3/4 hand-foot skin reaction (39% vs. 5%), stomatitis (10% vs. 0%), fatigue (18% vs. 9%), and dose reductions that were more frequent (51.9% vs. 7.8%). CONCLUSION: The addition of sorafenib to gemcitabine/capecitabine provided a clinically small but statistically significant PFS benefit in HER2-negative advanced breast cancer patients whose disease progressed during/after bevacizumab. Combination treatment was associated with manageable toxicities but frequently required dose reductions.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Capecitabina , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Progressão da Doença , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Fadiga/induzido quimicamente , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/análogos & derivados , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/efeitos adversos , Receptor ErbB-2/metabolismo , Dermatopatias/induzido quimicamente , Sorafenibe , Estomatite/induzido quimicamente , Resultado do Tratamento , Gencitabina
17.
Clin Lymphoma Myeloma Leuk ; 12(1): 26-31, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21752745

RESUMO

OBJECTIVE: To evaluate the efficacy and toxicity of the combination of VRCD (velcade/rituximab/cyclophosphamide/dexamethasone) in chemotherapy-naïve low-grade non-Hodgkin lymphoma or patients with transplantation-ineligible mantle cells. METHODS: The patients were treated with velcade, at 1.6 mg/m(2), on days 1, 8, 15, and 22 on every 35-day cycle. Rituximab was given at 375 mg/m(2) on the same days as velcade during cycle 1 and then only on day 1 in subsequent cycles. Dexamethasone was given orally at 40 mg on days 1, 2, 8, 9, 15, 16, 22, and 23. Cyclophosphamide was administered orally at 400 mg/m(2) on days 1-4. The patients had to meet criteria to initiate therapy and had to demonstrate adequate performance status and organ function. RESULTS: Twelve patients were enrolled, after which the study was closed due to a lack of funding. The median age was 68 years (37-83 years), with 83% having stage III/IV disease. Five patients had marginal zone, 4 had follicular, 2 had small lymphocytic, and 1 had mantle cell histologies. The overall response rate was 90% (complete response, 54%). At a median follow-up of 22 months, 9 (75%) patients remain alive, and the median time to progression has not been reached. A third of the patients required dose reductions after a median of 6.5 cycles. No grade 3 or 4 peripheral neuropathy was witnessed. CONCLUSIONS: Although the number of studied patients is small, VRCD appears safe and active as front-line therapy for low-grade non-Hodgkin lymphoma. Further studies are justified.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma não Hodgkin/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Alopecia/induzido quimicamente , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ácidos Borônicos/administração & dosagem , Ácidos Borônicos/efeitos adversos , Bortezomib , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Intervalo Livre de Doença , Esquema de Medicação , Fadiga/induzido quimicamente , Feminino , Humanos , Estimativa de Kaplan-Meier , Leucopenia/induzido quimicamente , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Pirazinas/administração & dosagem , Pirazinas/efeitos adversos , Rituximab , Resultado do Tratamento
18.
Cancer ; 106(11): 2459-65, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16615097

RESUMO

BACKGROUND: Doxorubicin plus ketoconazole has exhibited significant activity in patients with advanced prostate cancer. However, overall and cardiac-specific toxicity was reported to be high. Mitoxantrone has activity similar to that of doxorubicin, is less cardiotoxic, and is widely used to treat prostate cancer. The current study sought to evaluate the toxicity and activity of mitoxantrone plus ketoconazole in a cohort of patients with hormone-refractory prostate cancer. METHODS: Progression after medical or surgical castration and, for those patients receiving antiandrogens, progression after withdrawal was required, as was objective evidence of metastasis, castrate levels of testosterone, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2, and intact cardiac function. After enrollment onto a multicenter local consortium study, subjects were treated with mitoxantrone at a dose of 12 mg/m2 intravenously every 3 weeks plus continuous oral ketoconazole at a dose of 400 mg 3 times daily and ascorbic acid at a dose of 250 mg. Replacement doses of hydrocortisone were given. RESULTS: For 40 enrolled subjects, the median prostate-specific antigen and ECOG performance status were 68 and 1, respectively, 53% had Gleason scores of 8 to 10, and all had metastasis. Predominant Grade 3/4 toxicities were: neutropenia in 13%, neutropenic fever in 10%, and anemia in 13%. Of 37 evaluable patients, 8% achieved a complete remission (CR) and 62% achieved a partial remission (PR), for a CR plus PR rate of 70%. For soft tissue and bone disease, overall response rates were 13% and 8%, respectively. The median progression-free survival and overall survival were 10 months and 18 months, respectively. CONCLUSIONS: Mitoxantrone plus ketoconazole is well tolerated, is active in hormone-refractory prostate cancer, and should be studied further.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Humanos , Cetoconazol/administração & dosagem , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Neoplasias Hormônio-Dependentes/sangue , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Taxa de Sobrevida , Resultado do Tratamento
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