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1.
Mov Disord ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859549

RESUMO

BACKGROUND: Current treatments for Tourette syndrome (TS) and persistent tic disorder (PTD) are often insufficiently effective, inaccessible, and frequently associated with adverse events. Thus, we must continue to develop and test effective, accessible, and safe treatment options. OBJECTIVE: We aimed to conduct a pilot randomized controlled trial (RCT) comparing a novel, videoconference-delivered group mindfulness-based intervention for tics (MBIT) to videoconference-delivered group psychoeducation, relaxation, and supportive therapy (PRST) for adults with TS or PTD. METHODS: Thirty-two adults with TS or PTD were randomly assigned to receive 8 weeks of either MBIT or PRST. Tic severity, tic-related impairment, and global improvement were assessed by a trained, independent evaluator who was masked to treatment condition at baseline (week 0), posttreatment (week 9), 1-month follow-up, and 6-month follow-up. All study procedures were conducted online via secure videoconferencing. RESULTS: Twenty-eight participants began treatment and were included in analyses. MBIT, relative to PRST, was associated with a significantly greater decline in tic severity (d = 0.85) and tic-related impairment (d = 0.99) from baseline to posttreatment. Treatment response was significantly higher in MBIT (69%) than in PRST (13%). Neither treatment resulted in serious adverse effects. The durability of treatment outcomes is also reported and discussed. CONCLUSIONS: The results from this pilot RCT suggest that videoconference-delivered group MBIT may be an efficacious, accessible, and safe intervention for adults with tics. Future research is necessary to confirm these preliminary findings. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

2.
Exp Physiol ; 107(9): 1061-1070, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35923141

RESUMO

NEW FINDINGS: What is the central question of this study? Can bilateral knee extensor force accuracy be improved following 4 weeks of unilateral force accuracy training and are there any subsequent alterations to central and/or peripheral motor unit features? What is the main finding and its importance? In the trained limb only, knee extensor force tracking accuracy improved with reduced motor unit firing rate variability in the vastus lateralis, and there was no change to neuromuscular junction transmission instability. Interventional strategies to improve force accuracy may be directed to older/clinical populations where such improvements may aid performance of daily living activities. ABSTRACT: Muscle force output during sustained submaximal isometric contractions fluctuates around an average value and is partly influenced by variation in motor unit (MU) firing rates. MU firing rate (FR) variability seemingly reduces following exercise training interventions; however, much less is known with respect to peripheral MU properties. We therefore investigated whether targeted force accuracy training could lead to improved muscle functional capacity and control, in addition to determining any alterations of individual MU features. Ten healthy participants (seven females, three males, 27 ± 6 years, 170 ± 8 cm, 69 ± 16 kg) underwent a 4-week supervised, unilateral knee extensor force accuracy training intervention. The coefficient of variation for force (FORCECoV ) and sinusoidal wave force tracking accuracy (FORCESinu ) were determined at 25% maximal voluntary contraction (MVC) pre- and post-training. Intramuscular electromyography was utilised to record individual MU potentials from the vastus lateralis (VL) muscles at 25% MVC during sustained contractions, pre- and post-training. Knee extensor muscle strength remained unchanged following training, with no improvements in unilateral leg-balance. FORCECoV and FORCESinu significantly improved in only the trained knee extensors by ∼13% (P = 0.01) and ∼30% (P < 0.0001), respectively. MU FR variability significantly reduced in the trained VL by ∼16% (n = 8; P = 0.001), with no further alterations to MU FR or neuromuscular junction transmission instability. Our results suggest muscle force control and tracking accuracy is a trainable characteristic in the knee extensors, which is likely explained by the reduction in MU FR variability which was apparent in the trained limb only.


Assuntos
Joelho , Músculo Quadríceps , Eletromiografia , Feminino , Humanos , Contração Isométrica/fisiologia , Joelho/fisiologia , Articulação do Joelho/fisiologia , Masculino , Músculo Esquelético/fisiologia , Músculo Quadríceps/fisiologia
3.
Cereb Cortex ; 30(10): 5604-5615, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32488266

RESUMO

Synapses are involved in the communication of information from one neuron to another. However, a systematic analysis of synapse density in the neocortex from a diversity of species is lacking, limiting what can be understood about the evolution of this fundamental aspect of brain structure. To address this, we quantified synapse density in supragranular layers II-III and infragranular layers V-VI from primary visual cortex and inferior temporal cortex in a sample of 25 species of primates, including humans. We found that synapse densities were relatively constant across these levels of the cortical visual processing hierarchy and did not significantly differ with brain mass, varying by only 1.9-fold across species. We also found that neuron densities decreased in relation to brain enlargement. Consequently, these data show that the number of synapses per neuron significantly rises as a function of brain expansion in these neocortical areas of primates. Humans displayed the highest number of synapses per neuron, but these values were generally within expectations based on brain size. The metabolic and biophysical constraints that regulate uniformity of synapse density, therefore, likely underlie a key principle of neuronal connectivity scaling in primate neocortical evolution.


Assuntos
Evolução Biológica , Neocórtex/citologia , Neurônios/citologia , Primatas/anatomia & histologia , Sinapses , Adulto , Animais , Feminino , Humanos , Masculino , Córtex Visual Primário/citologia , Lobo Temporal/citologia , Adulto Jovem
4.
Nature ; 515(7528): 591-5, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-25209668

RESUMO

To prime reverse transcription, retroviruses require annealing of a transfer RNA molecule to the U5 primer binding site (U5-PBS) region of the viral genome. The residues essential for primer annealing are initially locked in intramolecular interactions; hence, annealing requires the chaperone activity of the retroviral nucleocapsid (NC) protein to facilitate structural rearrangements. Here we show that, unlike classical chaperones, the Moloney murine leukaemia virus NC uses a unique mechanism for remodelling: it specifically targets multiple structured regions in both the U5-PBS and tRNA(Pro) primer that otherwise sequester residues necessary for annealing. This high-specificity and high-affinity binding by NC consequently liberates these sequestered residues--which are exactly complementary--for intermolecular interactions. Furthermore, NC utilizes a step-wise, entropy-driven mechanism to trigger both residue-specific destabilization and residue-specific release. Our structures of NC bound to U5-PBS and tRNA(Pro) reveal the structure-based mechanism for retroviral primer annealing and provide insights as to how ATP-independent chaperones can target specific RNAs amidst the cellular milieu of non-target RNAs.


Assuntos
Modelos Moleculares , Vírus da Leucemia Murina de Moloney , Proteínas do Nucleocapsídeo , RNA de Transferência , RNA Viral/química , RNA Viral/metabolismo , Transcrição Reversa/fisiologia , Animais , Linhagem Celular , Genoma Viral/genética , Humanos , Vírus da Leucemia Murina de Moloney/química , Vírus da Leucemia Murina de Moloney/genética , Ressonância Magnética Nuclear Biomolecular , Proteínas do Nucleocapsídeo/química , Proteínas do Nucleocapsídeo/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , RNA de Transferência/química , RNA de Transferência/metabolismo , Transcrição Reversa/genética
5.
Plant Dis ; 104(5): 1274-1279, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32213125

RESUMO

In the southeastern United States, Armillaria root rot (ARR) is caused by Desarmillaria tabescens and has become the primary cause of premature mortality in peach orchards. Most rootstocks used in commercial orchards are susceptible and management options are limited. A postinfection practice known as root-collar excavation (RCE), which involves permanent removal of the soil from the base of the trunk, has been shown to improve yields and prolong the productive life of symptomatic trees. However, symptomatic trees already have an advanced infection at the base of the trunk. This study evaluated the efficacy of preventative RCE on the progression of tree mortality in two orchards that were planted in infested replant sites. To provide convincing data for growers, the study was carried out in a commercial orchard and an experimental orchard for 8 years. Furthermore, representative enterprise budgets and net present value (NPV) analysis were utilized to compare the profitability of the two approaches. Trees were planted shallow on berms (45 by 90 cm) to facilitate RCE with hoes and AirSpade 2 years later. Tree mortality in the RCE treatment of the experimental orchard was first observed in year 6 and increased 8% on average per year thereafter. In contrast, tree mortality in the "Grower Standard" treatment was first observed in year 4 and increased 12.7% on average per year thereafter. At the commercial orchard, tree mortality in the RCE treatment was first observed in year 7 and increased 1.9% on average thereafter, while tree mortality in the Grower Standard treatment first appeared in year 5 and increased 4.3% on average thereafter. The delayed onset of ARR-associated tree mortality and the lower annual tree mortality rate in the RCE treatment led to higher NPVs in both locations. There were no negative effects on yield or fruit quality. However, the new planting system can create horticultural challenges, including the formation of a proper berm, uneven ground around the tree interfering with tree care and harvest, increased erosion due to channeling of rainwater, and increased rootstock suckering. The RCE is a valid option for southeastern growers needing to manage high ARR disease pressure on replant sites or on sites only recently cleared from ARR-infected forest land.


Assuntos
Armillaria , Prunus persica , Frutas , Solo , Sudeste dos Estados Unidos
6.
Int J Mol Sci ; 20(2)2019 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-30669498

RESUMO

Root exudation is an important plant process by which roots release small molecules into the rhizosphere that serve in overall plant functioning. Yet, there is a major gap in our knowledge in translating plant root exudation in artificial systems (i.e., hydroponics, sterile media) to crops, specifically for soils expected in field conditions. Sorghum (Sorghum bicolor L. Moench) root exudation was determined using both ultra-performance liquid chromatography and gas chromatography mass spectrometry-based non-targeted metabolomics to evaluate variation in exudate composition of two sorghum genotypes among three substrates (sand, clay, and soil). Above and belowground plant traits were measured to determine the interaction between sorghum genotype and belowground substrate. Plant growth and quantitative exudate composition were found to vary largely by substrate. Two types of changes to rhizosphere metabolites were observed: rhizosphere-enhanced metabolites (REMs) and rhizosphere-abated metabolites (RAMs). More REMs and RAMs were detected in sand and clay substrates compared to the soil substrate. This study demonstrates that belowground substrate influences the root exudate profile in sorghum, and that two sorghum genotypes exuded metabolites at different magnitudes. However, metabolite identification remains a major bottleneck in non-targeted metabolite profiling of the rhizosphere.


Assuntos
Genótipo , Metaboloma , Metabolômica , Exsudatos de Plantas/metabolismo , Rizosfera , Sorghum/genética , Sorghum/metabolismo , Cromatografia Líquida , Biologia Computacional/métodos , Metabolismo Energético , Cromatografia Gasosa-Espectrometria de Massas , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Solo/química , Microbiologia do Solo , Estresse Fisiológico
7.
PLoS Genet ; 10(8): e1004533, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25167051

RESUMO

The mechanisms controlling cell fate determination and reprogramming are fundamental for development. A profound reprogramming, allowing the production of pluripotent cells in early embryos, takes place during the oocyte-to-embryo transition. To understand how the oocyte reprogramming potential is controlled, we sought Caenorhabditis elegans mutants in which embryonic transcription is initiated precociously in germ cells. This screen identified LIN-41, a TRIM-NHL protein and a component of the somatic heterochronic pathway, as a temporal regulator of pluripotency in the germline. We found that LIN-41 is expressed in the cytoplasm of developing oocytes, which, in lin-41 mutants, acquire pluripotent characteristics of embryonic cells and form teratomas. To understand LIN-41 function in the germline, we conducted structure-function studies. In contrast to other TRIM-NHL proteins, we found that LIN-41 is unlikely to function as an E3 ubiquitin ligase. Similar to other TRIM-NHL proteins, the somatic function of LIN-41 is thought to involve mRNA regulation. Surprisingly, we found that mutations predicted to disrupt the association of LIN-41 with mRNA, which otherwise compromise LIN-41 function in the heterochronic pathway in the soma, have only minor effects in the germline. Similarly, LIN-41-mediated repression of a key somatic mRNA target is dispensable for the germline function. Thus, LIN-41 appears to function in the germline and the soma via different molecular mechanisms. These studies provide the first insight into the mechanism inhibiting the onset of embryonic differentiation in developing oocytes, which is required to ensure a successful transition between generations.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Desenvolvimento Embrionário/genética , Oócitos/crescimento & desenvolvimento , Fatores de Transcrição/genética , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Diferenciação Celular/genética , Reprogramação Celular/genética , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/metabolismo , Mutação , Oócitos/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
8.
Dev Psychobiol ; 59(7): 840-847, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28888030

RESUMO

An autoshaping procedure was used to test the notion that conditioned stimuli (CSs) gain greater incentive salience during adolescence than young adulthood under conditions of social isolation rearing and food restriction. Rats were single-housed and placed on food restriction during 10 daily training sessions in which a lever (CS+ ) was presented then followed immediately by a food unconditioned stimulus (US). A second lever (CS- ) was presented on intermixed trials and was not reinforced. Despite the fact that food delivery was not contingent on the rats' behavior, all rats exhibited behaviors directed towards the lever (i.e., sign-tracking). In the adolescent group, the rate of lever pressing and the percentage of trials with a lever press were higher than in young adults. Initially, group differences were observed when rats were retrained when the adolescents had reached young adulthood. These findings support the hypothesis that cues that come to predict reward become imbued with excessive motivational value in adolescents, perhaps contributing to the hyper-responsiveness to reward-related stimuli typically observed during this period of development.


Assuntos
Comportamento Animal/fisiologia , Condicionamento Clássico/fisiologia , Desempenho Psicomotor/fisiologia , Recompensa , Fatores Etários , Animais , Masculino , Ratos , Ratos Long-Evans
9.
Biology (Basel) ; 12(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36671711

RESUMO

Competitive behavioural interactions between invasive and native freshwater crayfish are recognised as a key underlying mechanism behind the displacement of natives by invaders. However, in situ investigations into behavioural interactions between invasive and native crayfish are scarce. In Australian freshwater systems, the invasive Cherax destructor has spread into the ranges of many native Euastacus species, including the critically endangered Euastacus dharawalus. Staged contests between the two species in a laboratory setting found E. dharawalus to be the dominant competitor, however, this has yet to be corroborated in situ. Here, we used baited remote underwater video (BRUV) to examine in situ intra- and inter-specific behavioural interactions between E. dharawalus and C. destructor. We sought to evaluate patterns of dominance and differential contest dynamics between the species to provide indications of competition between the two species. We found E. dharawalus to be dominant over C. destructor based on pooled interspecific interaction data and size-grouped interactions where C. destructor was the smaller opponent. Alarmingly, however, when C. destructor was within a 10% size difference the dominance of E. dharawalus was lost, contrasting with the outcomes of the laboratory-staged study. In addition, we report that small C. destructor initiated significantly more contests than larger conspecifics and larger E. dharawalus, a pattern that was not observed in smaller E. dharawalus. Further, intraspecific interactions between C. destructor were significantly longer in duration than intraspecific interactions between E. dharawalus, indicating a willingness to continue fighting. Concerningly, these outcomes point towards inherent and greater aggressiveness in C. destructor relative to E. dharawalus and that only larger E. dharawalus hold a competitive advantage over C. destructor. Therefore, we conclude that C. destructor represents a substantial threat to E. dharawalus through competitive behavioural interactions. Further, due to the disparity between our findings and those produced from laboratory-staged contests, we recommend the use of in situ studies when determining the behavioural impacts of invasive crayfish on natives.

10.
Clin Cancer Res ; 27(14): 3834-3844, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33863809

RESUMO

PURPOSE: The Wee1 kinase inhibitor adavosertib abrogates cell-cycle arrest, leading to cell death. Prior testing of twice-daily adavosertib in patients with advanced solid tumors determined the recommended phase II dose (RPh2D). Here, we report results for once-daily adavosertib. PATIENTS AND METHODS: A 3 + 3 dose-escalation design was used, with adavosertib given once daily on days 1 to 5 and 8 to 12 in 21-day cycles. Molecular biomarkers of Wee1 activity, including tyrosine 15-phosphorylated Cdk1/2 (pY15-Cdk), were assessed in paired tumor biopsies. Whole-exome sequencing and RNA sequencing of remaining tumor tissue identified potential predictive biomarkers. RESULTS: Among the 42 patients enrolled, the most common toxicities were gastrointestinal and hematologic; dose-limiting toxicities were grade 4 hematologic toxicity and grade 3 fatigue. The once-daily RPh2D was 300 mg. Six patients (14%) had confirmed partial responses: four ovarian, two endometrial. Adavosertib plasma exposures were similar to those from twice-daily dosing. On cycle 1 day 8 (pre-dose), tumor pY15-Cdk levels were higher than baseline in four of eight patients, suggesting target rebound during the day 5 to 8 dosing break. One patient who progressed rapidly had a tumor WEE1 mutation and potentially compensatory PKMYT1 overexpression. Baseline CCNE1 overexpression occurred in both of two responding patients, only one of whom had CCNE1 amplification, and in zero of three nonresponding patients. CONCLUSIONS: We determined the once-daily adavosertib RPh2D and observed activity in patients with ovarian or endometrial carcinoma, including two with baseline CCNE1 mRNA overexpression. Future studies will determine whether CCNE1 overexpression is a predictive biomarker for adavosertib.


Assuntos
Proteínas de Ciclo Celular/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico , Neoplasias/tratamento farmacológico , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirazóis/uso terapêutico , Pirimidinonas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Esquema de Medicação , Inibidores Enzimáticos/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/química , Pirazóis/efeitos adversos , Pirimidinonas/efeitos adversos , Resultado do Tratamento
11.
J Neurosci ; 29(5): 1446-56, 2009 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-19193891

RESUMO

Serotonin modulates behavioral plasticity in both vertebrates and invertebrates and in Caenorhabditis elegans regulates key behaviors, including locomotion, aversive learning and olfaction through at least four different 5-HT receptors. In the present study, we examined the serotonergic stimulation of aversive responses to dilute octanol in animals containing null alleles of these 5-HT receptors. Both ser-1 and mod-1 null animals failed to increase sensitivity to dilute octanol on food/5-HT, in contrast to wild-type, ser-4 or ser-7 null animals. 5-HT sensitivity was restored by the expression of MOD-1 and SER-1 in the AIB or potentially the AIY, and RIA interneurons of mod-1 and ser-1 null animals, respectively. Because none of these 5-HT receptors appear to be expressed in the ASH sensory neurons mediating octanol sensitivity, we identified a 5-HT(6)-like receptor, F16D3.7(SER-5), that was required for food/5-HT-dependent increases in octanol sensitivity. ser-5 null animals failed to increase octanol sensitivity in the presence of food/5-HT and sensitivity could be restored by expression of SER-5 in the ASHs. Similarly, the RNAi knockdown of ser-5 expression in the ASHs of wild-type animals also abolished 5-HT-dependent increases in octanol sensitivity, suggesting that SER-5 modulates the octanol responsiveness of the ASHs directly. Together, these results suggest that multiple amine receptors, functioning at different levels within the locomotory circuit, are each essential for the serotonergic modulation of ASH-mediated aversive responses.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Células Quimiorreceptoras/fisiologia , Atividade Motora/fisiologia , Rede Nervosa/fisiologia , Receptores de Serotonina/fisiologia , Serotonina/fisiologia , 1-Octanol/farmacologia , Sequência de Aminoácidos , Animais , Células COS , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Células Cultivadas , Canais de Cloreto/genética , Canais de Cloreto/fisiologia , Chlorocebus aethiops , Técnicas de Silenciamento de Genes/métodos , Interneurônios/fisiologia , Dados de Sequência Molecular , Atividade Motora/genética , Receptores de Serotonina/genética , Receptores 5-HT2 de Serotonina/genética , Receptores 5-HT2 de Serotonina/fisiologia , Serotonina/deficiência , Serotonina/genética , Transdução de Sinais/fisiologia
12.
Cancer Chemother Pharmacol ; 85(5): 979-993, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32314030

RESUMO

PURPOSE: Following promising responses to the DNA methyltransferase (DNMT) inhibitor 5-fluoro-2'-deoxycytidine (FdCyd) combined with tetrahydrouridine (THU) in phase 1 testing, we initiated a non-randomized phase 2 study to assess response to this combination in patients with advanced solid tumor types for which tumor suppressor gene methylation is potentially prognostic. To obtain pharmacodynamic evidence for DNMT inhibition by FdCyd, we developed a novel method for detecting expression of tumor suppressor protein p16/INK4A in circulating tumor cells (CTCs). METHODS: Patients in histology-specific strata (breast, head and neck [H&N], or non-small cell lung cancers [NSCLC] or urothelial transitional cell carcinoma) were administered FdCyd (100 mg/m2) and THU (350 mg/m2) intravenously 5 days/week for 2 weeks, in 28-day cycles, and progression-free survival (PFS) rate and objective response rate (ORR) were evaluated. Blood specimens were collected for CTC analysis. RESULTS: Ninety-three eligible patients were enrolled (29 breast, 21 H&N, 25 NSCLC, and 18 urothelial). There were three partial responses. All strata were terminated early due to insufficient responses (H&N, NSCLC) or slow accrual (breast, urothelial). However, the preliminary 4-month PFS rate (42%) in the urothelial stratum exceeded the predefined goal-though the ORR (5.6%) did not. An increase in the proportion of p16-expressing cytokeratin-positive CTCs was detected in 69% of patients evaluable for clinical and CTC response, but was not significantly associated with clinical response. CONCLUSION: Further study of FdCyd + THU is potentially warranted in urothelial carcinoma but not NSCLC or breast or H&N cancer. Increase in the proportion of p16-expressing cytokeratin-positive CTCs is a pharmacodynamic marker of FdCyd target engagement.


Assuntos
Carcinoma de Células de Transição , Inibidor p16 de Quinase Dependente de Ciclina/análise , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , Desoxicitidina/análogos & derivados , Células Neoplásicas Circulantes/patologia , Neoplasias Urológicas , Administração Intravenosa , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Carcinoma de Células de Transição/metabolismo , Carcinoma de Células de Transição/patologia , Contagem de Células/métodos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/farmacocinética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Farmacogenética , Tetra-Hidrouridina/administração & dosagem , Tetra-Hidrouridina/efeitos adversos , Tetra-Hidrouridina/farmacocinética , Neoplasias Urológicas/metabolismo , Neoplasias Urológicas/patologia
13.
Cancer Res ; 80(2): 304-318, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31732654

RESUMO

The significance of the phenotypic plasticity afforded by epithelial-mesenchymal transition (EMT) for cancer progression and drug resistance remains to be fully elucidated in the clinic. We evaluated epithelial-mesenchymal phenotypic characteristics across a range of tumor histologies using a validated, high-resolution digital microscopic immunofluorescence assay (IFA) that incorporates ß-catenin detection and cellular morphology to delineate carcinoma cells from stromal fibroblasts and that quantitates the individual and colocalized expression of the epithelial marker E-cadherin (E) and the mesenchymal marker vimentin (V) at subcellular resolution ("EMT-IFA"). We report the discovery of ß-catenin+ cancer cells that coexpress E-cadherin and vimentin in core-needle biopsies from patients with various advanced metastatic carcinomas, wherein these cells are transitioning between strongly epithelial and strongly mesenchymal-like phenotypes. Treatment of carcinoma models with anticancer drugs that differ in their mechanism of action (the tyrosine kinase inhibitor pazopanib in MKN45 gastric carcinoma xenografts and the combination of tubulin-targeting agent paclitaxel with the BCR-ABL inhibitor nilotinib in MDA-MB-468 breast cancer xenografts) caused changes in the tumor epithelial-mesenchymal character. Moreover, the appearance of partial EMT or mesenchymal-like carcinoma cells in MDA-MB-468 tumors treated with the paclitaxel-nilotinib combination resulted in upregulation of cancer stem cell (CSC) markers and susceptibility to FAK inhibitor. A metastatic prostate cancer patient treated with the PARP inhibitor talazoparib exhibited similar CSC marker upregulation. Therefore, the phenotypic plasticity conferred on carcinoma cells by EMT allows for rapid adaptation to cytotoxic or molecularly targeted therapy and could create a form of acquired drug resistance that is transient in nature. SIGNIFICANCE: Despite the role of EMT in metastasis and drug resistance, no standardized assessment of EMT phenotypic heterogeneity in human carcinomas exists; the EMT-IFA allows for clinical monitoring of tumor adaptation to therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma/tratamento farmacológico , Plasticidade Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Animais , Antígenos CD/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Biópsia com Agulha de Grande Calibre , Caderinas/metabolismo , Carcinoma/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Indazóis , Masculino , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Vimentina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
14.
J Neurosci ; 27(49): 13402-12, 2007 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-18057198

RESUMO

Biogenic amines modulate key behaviors in both vertebrates and invertebrates. In Caenorhabditis elegans, tyramine (TA) and octopamine (OA) inhibit aversive responses to 100%, but not dilute (30%) octanol. TA and OA also abolish food- and serotonin-dependent increases in responses to dilute octanol in wild-type but not tyra-3(ok325) and f14d12.6(ok371) null animals, respectively, suggesting that TA and OA modulated responses to dilute octanol are mediated by separate, previously uncharacterized, G-protein-coupled receptors. TA and OA are high-affinity ligands for TYRA-3 and F14D12.6, respectively, based on their pharmacological characterization after heterologous expression. f14d12.6::gfp is expressed in the ASHs, the neurons responsible for sensitivity to dilute octanol, and the sra-6-dependent expression of F14D12.6 in the ASHs is sufficient to rescue OA sensitivity in f14d12.6(ok371) null animals. In contrast, tyra-3::gfp appears not to be expressed in the ASHs, but instead in other neurons, including the dopaminergic CEP/ADEs. However, although dopamine (DA) also inhibits 5-HT-dependent responses to dilute octanol, TA still inhibits in dop-2; dop-1; dop-3 animals that do not respond to DA and cat-2(tm346) and Pdat-1::ICE animals that lack significant dopaminergic signaling, suggesting that DA is not an intermediate in TA inhibition. Finally, responses to TA and OA selectively desensitize after preexposure to the amines. Our data suggest that although tyraminergic and octopaminergic signaling yield identical phenotypes in these olfactory assays, they act independently through distinct receptors to modulate the ASH-mediated locomotory circuit and that C. elegans is a useful model to study the aminergic modulation of sensory-mediated locomotory behaviors.


Assuntos
Comportamento Animal/fisiologia , Proteínas de Caenorhabditis elegans/fisiologia , Octopamina/fisiologia , Receptores de Amina Biogênica/fisiologia , Serotonina/fisiologia , Tiramina/fisiologia , Animais , Células CHO , Células COS , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/agonistas , Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Chlorocebus aethiops , Cricetinae , Cricetulus , Humanos , Camundongos , Células NIH 3T3 , Octopamina/farmacologia , Filogenia , Receptores de Amina Biogênica/agonistas , Receptores de Amina Biogênica/antagonistas & inibidores , Serotonina/farmacologia , Tiramina/farmacologia
15.
Cancer Res ; 78(24): 6807-6817, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30355619

RESUMO

: The intracellular effects and overall efficacies of anticancer therapies can vary significantly by tumor type. To identify patterns of drug-induced gene modulation that occur in different cancer cell types, we measured gene-expression changes across the NCI-60 cell line panel after exposure to 15 anticancer agents. The results were integrated into a combined database and set of interactive analysis tools, designated the NCI Transcriptional Pharmacodynamics Workbench (NCI TPW), that allows exploration of gene-expression modulation by molecular pathway, drug target, and association with drug sensitivity. We identified common transcriptional responses across agents and cell types and uncovered gene-expression changes associated with drug sensitivity. We also demonstrated the value of this tool for investigating clinically relevant molecular hypotheses and identifying candidate biomarkers of drug activity. The NCI TPW, publicly available at https://tpwb.nci.nih.gov, provides a comprehensive resource to facilitate understanding of tumor cell characteristics that define sensitivity to commonly used anticancer drugs. SIGNIFICANCE: The NCI Transcriptional Pharmacodynamics Workbench represents the most extensive compilation to date of directly measured longitudinal transcriptional responses to anticancer agents across a thoroughly characterized ensemble of cancer cell lines.


Assuntos
Ensaios de Seleção de Medicamentos Antitumorais/métodos , Perfilação da Expressão Gênica , National Cancer Institute (U.S.) , Pesquisa Translacional Biomédica/métodos , Antineoplásicos/farmacologia , Biomarcadores Tumorais , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Cloridrato de Erlotinib/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Internet , Análise de Sequência com Séries de Oligonucleotídeos , Transdução de Sinais , Estados Unidos , Vorinostat/farmacologia , Gencitabina
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