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1.
Strahlenther Onkol ; 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32211941

RESUMO

PURPOSE: The relation between functional imaging and intrapatient genetic heterogeneity remains poorly understood. The aim of our study was to investigate spatial sampling and functional imaging by FDG-PET/MRI to describe intrapatient tumour heterogeneity. METHODS: Six patients with oropharyngeal cancer were included in this pilot study. Two tumour samples per patient were taken and sequenced by next-generation sequencing covering 327 genes relevant in head and neck cancer. Corresponding regions were delineated on pretherapeutic FDG-PET/MRI images to extract apparent diffusion coefficients and standardized uptake values. RESULTS: Samples were collected within the primary tumour (n = 3), within the primary tumour and the involved lymph node (n = 2) as well as within two independent primary tumours (n = 1). Genetic heterogeneity of the primary tumours was limited and most driver gene mutations were found ubiquitously. Slightly increasing heterogeneity was found between primary tumours and lymph node metastases. One private predicted driver mutation within a primary tumour and one in a lymph node were found. However, the two independent primary tumours did not show any shared mutations in spite of a clinically suspected field cancerosis. No conclusive correlation between genetic heterogeneity and heterogeneity of PET/MRI-derived parameters was observed. CONCLUSION: Our limited data suggest that single sampling might be sufficient in some patients with oropharyngeal cancer. However, few driver mutations might be missed and, if feasible, spatial sampling should be considered. In two independent primary tumours, both lesions should be sequenced. Our data with a limited number of patients do not support the concept that multiparametric PET/MRI features are useful to guide biopsies for genetic tumour characterization.

2.
Aging (Albany NY) ; 122020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32205469

RESUMO

Machado-Joseph disease (MJD/SCA3) is the most common form of dominantly inherited ataxia worldwide. The disorder is caused by an expanded CAG repeat in the ATXN3 gene. Past studies have revealed that the length of the expansion partly explains the disease age at onset (AO) variability of MJD, which is confirmed in this study (Pearson's correlation coefficient R2 = 0.62). Using a total of 786 MJD patients from five different geographical origins, a genome-wide association study (GWAS) was conducted to identify additional AO modifying factors that could explain some of the residual AO variability. We identified nine suggestively associated loci (P < 1 × 10-5). These loci were enriched for genes involved in vesicle transport, olfactory signaling, and synaptic pathways. Furthermore, associations between AO and the TRIM29 and RAG genes suggests that DNA repair mechanisms might be implicated in MJD pathogenesis. Our study demonstrates the existence of several additional genetic factors, along with CAG expansion, that may lead to a better understanding of the genotype-phenotype correlation in MJD.

3.
Cancers (Basel) ; 12(3)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32110946

RESUMO

BACKGROUND: Mucosal and acral melanoma respond worse to immune checkpoint inhibitors (ICI) than cutaneous melanoma. MDM2/4 as well as EGFR amplifications are supposed to be associated with hyperprogression on ICI in diverse cancers. We therefore investigated the response of metastatic acral and mucosal melanoma to ICI in regard to MDM2/4 or EGFR amplifications and melanoma type. METHODS: We conducted a query of our melanoma registry, looking for patients with metastatic acral or mucosal melanoma treated by ICI. Whole exome sequencing, FISH and immunohistochemistry on melanoma tissue could be performed on 45 of the total cohort of 51 patients. Data were correlated with patients` responses to ICI and survival. RESULTS: 22 out of 51 patients had hyperprogressive disease (an increase in tumor load of >50% at the first staging). Hyperprogression occurred more often in case of MDM2/4 or EGFR amplification or <1% PD-L1 positive tumor cells. Nevertheless, this association was not significant. Interestingly, the anorectal melanoma type and the presence of liver metastases were significantly associated with worse survival. CONCLUSIONS: So far, we found no reliable predictive marker for patients who develop hyperprogression on ICI, specifically with regard to MDM2/4 or EGFR amplifications. Nevertheless, patients with anorectal melanoma, liver metastases or melanoma with amplified MYC seem to have an increased risk of not benefitting from ICI.

4.
J Mol Neurosci ; 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32112337

RESUMO

Mutations in THAP1 (THAP domain-containing apoptosis-associated protein 1) are responsible for DYT6 dystonia. Until now, more than eighty different mutations in THAP1 gene have been found in patients with primary dystonia, and two third of them are missense mutations. The potential pathogeneses of these missense mutations in human are largely elusive. In the present study, we generated stable transfected human neuronal cell lines expressing wild-type or mutated THAP1 proteins found in DYT6 patients. Transcriptional profiling using microarrays revealed a set of 28 common genes dysregulated in two mutated THAP1 (S21T and F81L) overexpression cell lines suggesting a common mechanism of these mutations. ChIP-seq showed that THAP1 can bind to the promoter of one of these genes, superoxide dismutase 2 (SOD2). Overexpression of THAP1 in SK-N-AS cells resulted in increased SOD2 protein expression, whereas fibroblasts from THAP1 patients have less SOD2 expression, which indicates that SOD2 is a direct target gene of THAP1. In addition, we show that some THAP1 mutations (C54Y and F81L) decrease the protein stability which might also be responsible for altered transcription regulation due to dosage insufficiency. Taking together, the current study showed different potential pathogenic mechanisms of THAP1 mutations which lead to the same consequence of DYT6 dystonia.

5.
Clin Genet ; 97(4): 621-627, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32056211

RESUMO

We recruited 103 families from Jordan with neurodevelopmental disorders (NDD) and patterns of inheritance mostly suggestive of autosomal recessive inheritance. In each family, we investigated at least one affected individual using exome sequencing and an in-house diagnostic variant interpretation pipeline including a search for copy number variation. This approach led us to identify the likely molecular defect in established disease genes in 37 families. We could identify 25 pathogenic nonsense and 11 missense variants as well as 3 pathogenic copy number variants and 1 repeat expansion. Notably, 11 of the disease-causal variants occurred de novo. In addition, we prioritized a homozygous frameshift variant in PUS3 in two sisters with intellectual disability. To our knowledge, PUS3 has been postulated only recently as a candidate disease gene for intellectual disability in a single family with three affected siblings. Our findings provide additional evidence to establish loss of PUS3 function as a cause of intellectual disability.

6.
Hum Mol Genet ; 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31960910

RESUMO

Proteolytic fragmentation of polyglutamine-expanded ataxin-3 is a concomitant and modifier of the molecular pathogenesis of Machado-Joseph disease (MJD), the most common autosomal dominant cerebellar ataxia. Calpains, a group of calcium-dependent cysteine proteases, are important mediators of ataxin-3 cleavage and implicated in multiple neurodegenerative conditions. Pharmacologic and genetic approaches lowering calpain activity showed beneficial effects on molecular and behavioural disease characteristics in MJD model organisms. However, specifically targeting one of the calpain isoforms by genetic means has not yet been evaluated as a potential therapeutic strategy. In our study, we tested whether calpains are overactivated in the MJD context and if reduction or ablation of calpain-1 expression ameliorates the disease-associated phenotype in MJD cells and mice. In all analysed MJD models, we detected an elevated calpain activity at baseline. Lowering or removal of calpain-1 in cells or mice counteracted calpain system overactivation and led to reduced cleavage of ataxin-3 without affecting its aggregation. Moreover, calpain-1 knockout in YAC84Q mice alleviated excessive fragmentation of important synaptic proteins. Despite worsening some motor characteristics, YAC84Q mice showed a rescue of body weight loss and extended survival upon calpain-1 knockout. Together, our findings emphasize the general potential of calpains as a therapeutic target in MJD and other neurodegenerative diseases.

7.
Neurobiol Dis ; 134: 104634, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31678405

RESUMO

Dystonia is a neurological movement disorder characterized by sustained or intermittent involuntary muscle contractions. Loss-of-function mutations in the GNAL gene have been identified to be the cause of "isolated" dystonia DYT25. The GNAL gene encodes for the guanine nucleotide-binding protein G(olf) subunit alpha (Gαolf), which is mainly expressed in the olfactory bulb and the striatum and functions as a modulator during neurotransmission coupling with D1R and A2AR. Previously, heterozygous Gαolf -deficient mice (Gnal+/-) have been generated and showed a mild phenotype at basal condition. In contrast, homozygous deletion of Gnal in mice (Gnal-/-) resulted in a significantly reduced survival rate. In this study, using the CRISPR-Cas9 system we generated and characterized heterozygous Gnal knockout rats (Gnal+/-) with a 13 base pair deletion in the first exon of the rat Gnal splicing variant 2, a major isoform in both human and rat striatum. Gnal+/- rats showed early-onset phenotypes associated with impaired dopamine transmission, including reduction in locomotor activity, deficits in rotarod performance and an abnormal motor skill learning ability. At cellular and molecular level, we found down-regulated Arc expression, increased cell surface distribution of AMPA receptors, and the loss of D2R-dependent corticostriatal long-term depression (LTD) in Gnal+/- rats. Based on the evidence that D2R activity is normally inhibited by adenosine A2ARs, co-localized on the same population of striatal neurons, we show that blockade of A2ARs restores physiological LTD. This animal model may be a valuable tool for investigating Gαolf function and finding a suitable treatment for dystonia associated with deficient dopamine transmission.

8.
Neuropharmacology ; 162: 107812, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622602

RESUMO

One of the pathological hallmarks of Huntington disease (HD) is accumulation of the disease-causing mutant huntingtin (mHTT), which leads to the disruption of a variety of cellular functions, ultimately resulting in cell death. Induction of autophagy, for example by the inhibition of mechanistic target of rapamycin (mTOR) signaling, has been shown to reduce HTT levels and aggregates. While rapalogs like rapamycin allosterically inhibit the mTOR complex 1 (TORC1), ATP-competitive mTOR inhibitors suppress activities of TORC1 and TORC2 and have been shown to be more efficient in inducing autophagy and reducing protein levels and aggregates than rapalogs. The ability to cross the blood-brain barrier of first generation catalytic mTOR inhibitors has so far been limited, and therefore sufficient target coverage in the brain could not be reached. Two novel, brain penetrant compounds - the mTORC1/2 inhibitor PQR620, and the dual pan-phosphoinositide 3-kinase (PI3K) and mTORC1/2 kinase inhibitor PQR530 - were evaluated by assessing their potential to induce autophagy and reducing mHTT levels. For this purpose, expression levels of autophagic markers and well-defined mTOR targets were analyzed in STHdh cells and HEK293T cells and in mouse brains. Both compounds potently inhibited mTOR signaling in cell models as well as in mouse brain. As proof of principle, reduction of aggregates and levels of soluble mHTT were demonstrated upon treatment with both compounds. Originally developed for cancer treatment, these second generation mTORC1/2 and PI3K/mTOR inhibitors show brain penetrance and efficacy in cell models of HD, making them candidate molecules for further investigations in HD.

9.
Z Gastroenterol ; 57(11): 1309-1320, 2019 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-31739377

RESUMO

INTRODUCTION: Lynch syndrome (LS) is the most common hereditary colorectal cancer syndrome and accounts for ~3 % of all CRCs. This autosomal dominant disorder is caused by germline mutations in DNA mismatch repair genes (MLH1, MSH2, MSH6, PMS2, and EPCAM). One in 300 individuals of the general population are considered to be mutation carriers (300 000 individuals/Germany). Mutation carriers are at a high CRC risk of 15-46 % till the age of 75 years. LS also includes a variety of extracolonic malignancies such as endometrial, small bowel, gastric, urothelial, and other cancers. METHODS: The German Consortium for Familial Intestinal Cancer consists of 14 university centers in Germany. The aim of the consortium is to develop and evaluate surveillance programs and to further translate the results in clinical care. We have revisited and updated the clinical management guidelines for LS patients in Germany. RESULTS: A surveillance colonoscopy should be performed every 12-24 months starting at the age of 25 years. At diagnosis of first colorectal cancer, an oncological resection is advised, an extended resection (colectomy with ileorectal anastomosis) has to be discussed with the patient. The lifetime risk for gastric cancer is 0.2-13 %. Gastric cancers detected during surveillance have a lower tumor stage compared to symptom-driven detection. The lifetime risk for small bowel cancer is 4-8 %. About half of small bowel cancer is located in the duodenum and occurs before the age of 35 years in 10 % of all cases. Accordingly, patients are advised to undergo an esophagogastroduodenoscopy every 12-36 months starting by the age of 25 years. CONCLUSION: LS colonic and extracolonic clinical management, surveillance and therapy are complex and several aspects remain unclear. In the future, surveillance and clinical management need to be more tailored to gene and gender. Future prospective trials are needed.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/patologia , Reparo de Erro de Pareamento de DNA , Endoscopia do Sistema Digestório/métodos , Guias de Prática Clínica como Assunto , Comportamento de Redução do Risco , Neoplasias Colorretais , Neoplasias Colorretais Hereditárias sem Polipose/genética , Alemanha , Humanos , Vigilância da População , Fatores de Tempo
10.
Front Neurosci ; 13: 1032, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31749671

RESUMO

Recent findings suggest an implication of the gut microbiome in Parkinson's disease (PD) patients. PD onset and progression has also been linked with various environmental factors such as physical activity, exposure to pesticides, head injury, nicotine, and dietary factors. In this study, we used a mouse model, overexpressing the complete human SNCA gene (SNCA-TG mice) modeling familial and sporadic forms of PD to study whether environmental conditions such as standard vs. enriched environment changes the gut microbiome and influences disease progression. We performed 16S rRNA DNA sequencing on fecal samples for microbiome analysis and studied fecal inflammatory calprotectin from the colon of control and SNCA-TG mice kept under standard environment (SE) and enriched environment (EE) conditions. The overall composition of the gut microbiota was not changed in SNCA-TG mice compared with WT in EE with respect to SE. However, individual gut bacteria at genus level such as Lactobacillus sp. was a significant changed in the SNCA-TG mice. EE significantly reduced colon fecal inflammatory calprotectin protein in WT and SNCA-TG EE compared to SE. Moreover, EE reduces the pro-inflammatory cytokines in the feces and inflammation inducing genes in the colon. Our data suggest that an enriched social environment has a positive effect on the induction of SNCA mediated inflammation in the intestine and by modulating anti-inflammatory gut bacteria.

12.
eNeuro ; 6(6)2019.
Artigo em Inglês | MEDLINE | ID: mdl-31604813

RESUMO

Gait analysis of transgenic mice and rats modeling human diseases often suffers from the condition that those models exhibit genotype-driven differences in body size, weight, and length. Thus, we hypothesized that scaling by the silhouette length improves the reliability of gait analysis allowing normalization for individual body size differences. Here, we computed video-derived silhouette length and area parameters from a standard markerless gait analysis system using image-processing techniques. By using length- and area-derived data along with body weight and age, we systematically scaled individual gait parameters. We compared these different scaling approaches and report here that normalization for silhouette length improves the validity and reliability of gait analysis in general. The application of this silhouette length scaling to transgenic Huntington disease mice and Parkinson´s disease rats identifies the remaining differences reflecting more reliable, body length-independent motor functional differences. Overall, this emphasizes the need for silhouette-length-based intra-assay scaling as an improved standard approach in rodent gait analysis.

13.
Nat Commun ; 10(1): 3945, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477726

RESUMO

Neuroinflammation is one of the hallmarks of Parkinson's disease (PD) and may contribute to midbrain dopamine (DA) neuron degeneration. Recent studies link chronic inflammation with failure to resolve early inflammation, a process operated by specialized pro-resolving mediators, including resolvins. However, the effects of stimulating the resolution of inflammation in PD - to modulate disease progression - still remain unexplored. Here we show that rats overexpressing human α-synuclein (Syn) display altered DA neuron properties, reduced striatal DA outflow and motor deficits prior to nigral degeneration. These early alterations are coupled with microglia activation and perturbations of inflammatory and pro-resolving mediators, namely IFN-γ and resolvin D1 (RvD1). Chronic and early RvD1 administration in Syn rats prevents central and peripheral inflammation, as well as neuronal dysfunction and motor deficits. We also show that endogenous RvD1 is decreased in human patients with early-PD. Our results suggest there is an imbalance between neuroinflammatory and pro-resolving processes in PD.


Assuntos
Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/administração & dosagem , Inflamação/prevenção & controle , Degeneração Neural/prevenção & controle , Doença de Parkinson/prevenção & controle , Animais , Ácidos Docosa-Hexaenoicos/genética , Ácidos Docosa-Hexaenoicos/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Humanos , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
14.
BMC Cancer ; 19(1): 787, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395037

RESUMO

BACKGROUND: Inherited pathogenic variants in BRCA1 and BRCA2 are the most common causes of hereditary breast and ovarian cancer (HBOC). The risk of developing breast cancer by age 80 in women carrying a BRCA1 pathogenic variant is 72%. The lifetime risk varies between families and even within affected individuals of the same family. The cause of this variability is largely unknown, but it is hypothesized that additional genetic factors contribute to differences in age at onset (AAO). Here we investigated whether truncating and rare missense variants in genes of different DNA-repair pathways contribute to this phenomenon. METHODS: We used extreme phenotype sampling to recruit 133 BRCA1-positive patients with either early breast cancer onset, below 35 (early AAO cohort) or cancer-free by age 60 (controls). Next Generation Sequencing (NGS) was used to screen for variants in 311 genes involved in different DNA-repair pathways. RESULTS: Patients with an early AAO (73 women) had developed breast cancer at a median age of 27 years (interquartile range (IQR); 25.00-27.00 years). A total of 3703 variants were detected in all patients and 43 of those (1.2%) were truncating variants. The truncating variants were found in 26 women of the early AAO group (35.6%; 95%-CI 24.7 - 47.7%) compared to 16 women of controls (26.7%; 95%-CI 16.1 to 39.7%). When adjusted for environmental factors and family history, the odds ratio indicated an increased breast cancer risk for those carrying an additional truncating DNA-repair variant to BRCA1 mutation (OR: 3.1; 95%-CI 0.92 to 11.5; p-value = 0.07), although it did not reach the conventionally acceptable significance level of 0.05. CONCLUSIONS: To our knowledge this is the first time that the combined effect of truncating variants in DNA-repair genes on AAO in patients with hereditary breast cancer is investigated. Our results indicate that co-occurring truncating variants might be associated with an earlier onset of breast cancer in BRCA1-positive patients. Larger cohorts are needed to confirm these results.


Assuntos
Proteína BRCA1/genética , Biomarcadores Tumorais , Neoplasias da Mama/genética , Reparo do DNA , Predisposição Genética para Doença , Deleção de Sequência , Adulto , Idade de Início , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Bases de Dados Genéticas , Feminino , Estudos de Associação Genética , Loci Gênicos , Alemanha/epidemiologia , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Vigilância da População , Medição de Risco , Fatores de Risco
15.
J Neurosci Methods ; 326: 108367, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31351096

RESUMO

BACKGROUND: Motor impairment appears as a characteristic symptom of several diseases and injuries. Therefore, tests for analyzing motor dysfunction are widely applied across preclinical models and disease stages. Among those, gait analysis tests are commonly used, but they generate a huge number of gait parameters. Thus, complications in data analysis and reporting raise, which often leads to premature parameter selection. NEW METHODS: In order to avoid arbitrary parameter selection, we present here a systematic initial data analysis by utilizing heat-maps for data reporting. We exemplified this approach within an intervention study, as well as applied it to two longitudinal studies in rodent models related to Parkinson's disease (PD) and Huntington disease (HD). RESULTS: The systematic initial data analysis (IDA) is feasible for exploring gait parameters, both in experimental and longitudinal studies. The resulting heat maps provided a visualization of gait parameters within a single chart, highlighting important clusters of differences. COMPARISON WITH EXISTING METHOD: Often, premature parameter selection is practiced, lacking comprehensiveness. Researchers often use multiple separated graphs on distinct gait parameters for reporting. Additionally, negative results are often not reported. CONCLUSIONS: Heat mapping utilized in initial data analysis is advantageous for reporting clustered gait parameter differences in one single chart and improves data mining.

16.
J Neural Transm (Vienna) ; 126(7): 815-840, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31240402

RESUMO

Parkinson's disease (PD) comprises a spectrum of disorders with differing subtypes, the vast majority of which share Lewy bodies (LB) as a characteristic pathological hallmark. The process(es) underlying LB generation and its causal trigger molecules are not yet fully understood. α-Synuclein (α-syn) is a major component of LB and SNCA gene missense mutations or duplications/triplications are causal for rare hereditary forms of PD. As typical sporadic PD is associated with LB pathology, a factor of major importance is the study of the α-syn protein and its pathology. α-Syn pathology is, however, also evident in multiple system atrophy (MSA) and Lewy body disease (LBD), making it non-specific for PD. In addition, there is an overlap of these α-synucleinopathies with other protein-misfolding diseases. It has been proven that α-syn, phosphorylated tau protein (pτ), amyloid beta (Aß) and other proteins show synergistic effects in the underlying pathogenic mechanisms. Multiple cell death mechanisms can induce pathological protein-cascades, but this can also be a reverse process. This holds true for the early phases of the disease process and especially for the progression of PD. In conclusion, while rare SNCA gene mutations are causal for a minority of familial PD patients, in sporadic PD (where common SNCA polymorphisms are the most consistent genetic risk factor across populations worldwide, accounting for 95% of PD patients) α-syn pathology is an important feature. Conversely, with regard to the etiopathogenesis of α-synucleinopathies PD, MSA and LBD, α-syn is rather a bystander contributing to multiple neurodegenerative processes, which overlap in their composition and individual strength. Therapeutic developments aiming to impact on α-syn pathology should take this fact into consideration.

17.
Acta Neuropathol ; 138(4): 535-550, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31254094

RESUMO

The conversion of endogenous alpha-synuclein (asyn) to pathological asyn-enriched aggregates is a hallmark of Parkinson's disease (PD). These inclusions can be detected in the central and enteric nervous system (ENS). Moreover, gastrointestinal symptoms can appear up to 20 years before the diagnosis of PD. The dual-hit hypothesis posits that pathological asyn aggregation starts in the ENS, and retrogradely spreads to the brain. In this study, we tested this hypothesis by directly injecting preformed asyn fibrils into the duodenum wall of wild-type rats and transgenic rats with excess levels of human asyn. We provide a meticulous characterization of the bacterial artificial chromosome (BAC) transgenic rat model with respect to initial propagation of pathological asyn along the parasympathetic and sympathetic pathways to the brainstem, by performing immunohistochemistry at early time points post-injection. Induced pathology was observed in all key structures along the sympathetic and parasympathetic pathways (ENS, autonomic ganglia, intermediolateral nucleus of the spinal cord (IML), heart, dorsal motor nucleus of the vagus, and locus coeruleus (LC)) and persisted for at least 4 months post-injection. In contrast, asyn propagation was not detected in wild-type rats, nor in vehicle-injected BAC rats. The presence of pathology in the IML, LC, and heart indicate trans-synaptic spread of the pathology. Additionally, the observed asyn inclusions in the stomach and heart may indicate secondary anterograde propagation after initial retrograde spreading. In summary, trans-synaptic propagation of asyn in the BAC rat model is fully compatible with the "body-first hypothesis" of PD etiopathogenesis. To our knowledge, this is the first animal model evidence of asyn propagation to the heart, and the first indication of bidirectional asyn propagation via the vagus nerve, i.e., duodenum-to-brainstem-to-stomach. The BAC rat model could be very valuable for detailed mechanistic studies of the dual-hit hypothesis, and for studies of disease modifying therapies targeting early pathology in the gastrointestinal tract.

18.
Cells ; 8(6)2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31208073

RESUMO

Intrastriatal administration of mesenchymal stem cells (MSCs) has shown beneficial effects in rodent models of Huntington disease (HD). However, the invasive nature of surgical procedure and its potential to trigger the host immune response may limit its clinical use. Hence, we sought to evaluate the non-invasive intranasal administration (INA) of MSC delivery as an effective alternative route in HD. GFP-expressing MSCs derived from bone marrow were intranasally administered to 4-week-old R6/2 HD transgenic mice. MSCs were detected in the olfactory bulb, midbrain and striatum five days post-delivery. Compared to phosphate-buffered saline (PBS)-treated littermates, MSC-treated R6/2 mice showed an increased survival rate and attenuated circadian activity disruption assessed by locomotor activity. MSCs increased the protein expression of DARPP-32 and tyrosine hydroxylase (TH) and downregulated gene expression of inflammatory modulators in the brain 7.5 weeks after INA. While vehicle treated R6/2 mice displayed decreased Iba1 expression and altered microglial morphology in comparison to the wild type littermates, MSCs restored both, Iba1 level and the thickness of microglial processes in the striatum of R6/2 mice. Our results demonstrate significantly ameliorated phenotypes of R6/2 mice after MSCs administration via INA, suggesting this method as an effective delivering route of cells to the brain for HD therapy.


Assuntos
Dopamina/metabolismo , Doença de Huntington/fisiopatologia , Doença de Huntington/terapia , Inflamação/patologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Transmissão Sináptica , Administração Intranasal , Animais , Encéfalo/patologia , Encéfalo/fisiopatologia , Rastreamento de Células , Ritmo Circadiano , Modelos Animais de Doenças , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Regulação da Expressão Gênica , Humanos , Doença de Huntington/genética , Inflamação/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/metabolismo , Microglia/patologia , Atividade Motora , Fatores de Crescimento Neural/metabolismo , Sono , Análise de Sobrevida , Tirosina 3-Mono-Oxigenase/metabolismo
19.
Strahlenther Onkol ; 195(9): 771-779, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31123786

RESUMO

PURPOSE: Genetic tumour profiles and radiomic features can be used to complement clinical information in head and neck squamous cell carcinoma (HNSCC) patients. Radiogenomics imply the potential to investigate complementarity or interrelations of radiomic and genomic features, and prognostic factors might be determined. The aim of our study was to explore radiogenomics in HNSCC. METHODS: For 20 HNSCC patients treated with primary radiochemotherapy, next-generation sequencing (NGS) of tumour and corresponding normal tissue was performed. In total, 327 genes were investigated by panel sequencing. Radiomic features were extracted from computed tomography data. A hypothesis-driven approach was used for radiogenomic correlations of selected image-based heterogeneity features and well-known driver gene mutations in HNSCC. RESULTS: The most frequently mutated driver genes in our cohort were TP53 (involved in cell cycle control), FAT1 (Wnt signalling, cell-cell contacts, migration) and KMT2D (chromatin modification). Radiomic features of heterogeneity did not correlate significantly with somatic mutations in TP53 or KMT2D. However, somatic mutations in FAT1 and smaller primary tumour volumes were associated with reduced radiomic intra-tumour heterogeneity. CONCLUSION: The landscape of somatic variants in our cohort is well in line with previous reports. An association of somatic mutations in FAT1 with reduced radiomic tumour heterogeneity could potentially elucidate the previously described favourable outcomes of these patients. Larger studies are needed to validate this exploratory data in the future.


Assuntos
Caderinas/genética , Análise Mutacional de DNA , Proteínas de Ligação a DNA/genética , Heterogeneidade Genética , Proteínas de Neoplasias/genética , Neoplasias Otorrinolaringológicas/genética , Neoplasias Otorrinolaringológicas/radioterapia , Proteína Supressora de Tumor p53/genética , Correlação de Dados , Humanos , Tolerância a Radiação
20.
J Clin Invest ; 129(6): 2390-2403, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-31063986

RESUMO

A disintegrine and metalloproteinase 10 (ADAM10) is implicated in synaptic function through its interaction with postsynaptic receptors and adhesion molecules. Here, we report that levels of active ADAM10 are increased in Huntington's disease (HD) mouse cortices and striata and in human postmortem caudate. We show that, in the presence of polyglutamine-expanded (polyQ-expanded) huntingtin (HTT), ADAM10 accumulates at the postsynaptic densities (PSDs) and causes excessive cleavage of the synaptic protein N-cadherin (N-CAD). This aberrant phenotype is also detected in neurons from HD patients where it can be reverted by selective silencing of mutant HTT. Consistently, ex vivo delivery of an ADAM10 synthetic inhibitor reduces N-CAD proteolysis and corrects electrophysiological alterations in striatal medium-sized spiny neurons (MSNs) of 2 HD mouse models. Moreover, we show that heterozygous conditional deletion of ADAM10 or delivery of a competitive TAT-Pro-ADAM10709-729 peptide in R6/2 mice prevents N-CAD proteolysis and ameliorates cognitive deficits in the mice. Reduction in synapse loss was also found in R6/2 mice conditionally deleted for ADAM10. Taken together, these results point to a detrimental role of hyperactive ADAM10 at the HD synapse and provide preclinical evidence of the therapeutic potential of ADAM10 inhibition in HD.

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