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1.
Biotechnol Bioeng ; 120(10): 3079-3091, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37395340

RESUMO

Current research tools for preclinical drug development such as rodent models and two-dimensional immortalized monocultures have failed to serve as effective translational models for human central nervous system (CNS) disorders. Recent advancements in the development of induced pluripotent stem cells (iPSCs) and three-dimensional (3D) culturing can improve the in vivo-relevance of preclinical models, while generating 3D cultures though novel bioprinting technologies can offer increased scalability and replicability. As such, there is a need to develop platforms that combine iPSC-derived cells with 3D bioprinting to produce scalable, tunable, and biomimetic cultures for preclinical drug discovery applications. We report a biocompatible poly(ethylene glycol)-based matrix which incorporates Arg-Gly-Asp and Tyr-Ile-Gly-Ser-Arg peptide motifs and full-length collagen IV at a stiffness similar to the human brain (1.5 kPa). Using a high-throughput commercial bioprinter we report the viable culture and morphological development of monocultured iPSC-derived astrocytes, brain microvascular endothelial-like cells, neural progenitors, and neurons in our novel matrix. We also show that this system supports endothelial-like vasculogenesis and enhances neural differentiation and spontaneous activity. This platform forms a foundation for more complex, multicellular models to facilitate high-throughput translational drug discovery for CNS disorders.


Assuntos
Bioimpressão , Células-Tronco Pluripotentes Induzidas , Humanos , Astrócitos , Bioimpressão/métodos , Diferenciação Celular , Sistema Nervoso Central , Células-Tronco , Impressão Tridimensional
2.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33803967

RESUMO

The life expectancy of patients with high-grade glioma (HGG) has not improved in decades. One of the crucial tools to enable future improvement is advanced models that faithfully recapitulate the tumour microenvironment; they can be used for high-throughput screening that in future may enable accurate personalised drug screens. Currently, advanced models are crucial for identifying and understanding potential new targets, assessing new chemotherapeutic compounds or other treatment modalities. Recently, various methodologies have come into use that have allowed the validation of complex models-namely, spheroids, tumouroids, hydrogel-embedded cultures (matrix-supported) and advanced bioengineered cultures assembled with bioprinting and microfluidics. This review is designed to present the state of advanced models of HGG, whilst focusing as much as is possible on the paediatric form of the disease. The reality remains, however, that paediatric HGG (pHGG) models are years behind those of adult HGG. Our goal is to bring this to light in the hope that pGBM models can be improved upon.


Assuntos
Antineoplásicos/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Glioblastoma/tratamento farmacológico , Esferoides Celulares/efeitos dos fármacos , Adulto , Antineoplásicos/química , Bioimpressão/métodos , Criança , Glioblastoma/patologia , Humanos , Hidrogéis/química , Hidrogéis/uso terapêutico , Microfluídica/métodos , Microambiente Tumoral/efeitos dos fármacos
3.
J Neurochem ; 149(4): 535-550, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30592774

RESUMO

Targeting epigenetic mechanisms has shown promise against several cancers but has so far been unsuccessful against glioblastoma (GBM). Altered histone 3 lysine 4 methylation and increased lysine-specific histone demethylase 1A (LSD1) expression in GBM tumours nonetheless suggest that epigenetic mechanisms are involved in GBM. We engineered a dual-action prodrug, which is activated by the high hydrogen peroxide levels associated with GBM cells. This quinone methide phenylaminecyclopropane prodrug releases the LSD1 inhibitor 2-phenylcyclopropylamine with the glutathione scavenger para-quinone methide to trigger apoptosis in GBM cells. Quinone methide phenylaminocyclopropane impaired GBM cell behaviours in two-dimensional and three-dimensional assays, and triggered cell apoptosis in several primary and immortal GBM cell cultures. These results support our double-hit hypothesis of potentially targeting LSD1 and quenching glutathione, in order to impair and kill GBM cells but not healthy astrocytes. Our data suggest this strategy is effective at selectively targeting GBM and potentially other types of cancers. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Pró-Fármacos/farmacologia , Compostos de Anilina/farmacologia , Células Cultivadas , Ciclopropanos/farmacologia , Desenho de Fármacos , Glutationa/antagonistas & inibidores , Histona Desmetilases/antagonistas & inibidores , Humanos , Indolquinonas/farmacologia
4.
Cell Commun Signal ; 15(1): 9, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28143584

RESUMO

BACKGROUND: Translationally controlled tumour protein TCTP is an anti-apoptotic protein frequently overexpressed in cancers, where high levels are often associated with poor patient outcome. TCTP may be involved in protecting cancer cells against the cytotoxic action of anti-cancer drugs. Here we study the early increase of TCTP levels in human colorectal cancer (CRC) and the regulation of TCTP expression in HCT116 colon cancer cells, in response to treatment with the anti-cancer drugs 5-FU and oxaliplatin. METHODS: Using immunohistochemistry, we assessed TCTP levels in surgical samples from adenomas and adenocarcinomas of the colon, compared to normal colon tissue. We also studied the regulation of TCTP in HCT116 colon cancer cells in response to 5-FU and oxaliplatin by western blotting. TCTP mRNA levels were assessed by RT-qPCR. We used mTOR kinase inhibitors to demonstrate mTOR-dependent translational regulation of TCTP under these conditions. Employing the Real-Time Cell Analysis (RTCA) System and the MTS assay, we investigated the effect of TCTP-knockdown on the sensitivity of HCT116 cells to the anti-cancer drugs 5-FU and oxaliplatin. RESULTS: 1. TCTP levels are significantly increased in colon adenomas and adenocarcinomas, compared to normal colon tissue. 2. TCTP protein levels are about 4-fold upregulated in HCT116 colon cancer cells, in response to 5-FU and oxaliplatin treatment, whereas TCTP mRNA levels are down regulated. 3. mTOR kinase inhibitors prevented the up-regulation of TCTP protein, indicating that TCTP is translationally regulated through the mTOR complex 1 signalling pathway under these conditions. 4. Using two cellular assay systems, we demonstrated that TCTP-knockdown sensitises HCT116 cells to the cytotoxicity caused by 5-FU and oxaliplatin. CONCLUSIONS: Our results demonstrate that TCTP levels increase significantly in the early stages of CRC development. In colon cancer cells, expression of this protein is largely upregulated during treatment with the DNA-damaging anti-cancer drugs 5-FU and oxaliplatin, as part of the cellular stress response. TCTP may thus contribute to the development of anti-cancer drug resistance. These findings indicate that TCTP might be suitable as a biomarker and that combinatorial treatment using 5-FU/oxaliplatin, together with mTOR kinase inhibitors, could be a route to preventing the development of resistance to these drugs.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fluoruracila/farmacologia , Compostos Organoplatínicos/farmacologia , Biomarcadores Tumorais/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Morte Celular/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos/metabolismo , Oxaliplatina , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Proteína Tumoral 1 Controlada por Tradução
5.
Cell Mol Life Sci ; 73(19): 3693-709, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27154043

RESUMO

Induced pluripotent stem cells and embryonic stem cells have revolutionized cellular neuroscience, providing the opportunity to model neurological diseases and test potential therapeutics in a pre-clinical setting. The power of these models has been widely discussed, but the potential pitfalls of stem cell differentiation in this research are less well described. We have analyzed the literature that describes differentiation of human pluripotent stem cells into three neural cell types that are commonly used to study diseases, including forebrain cholinergic neurons for Alzheimer's disease, midbrain dopaminergic neurons for Parkinson's disease and cortical astrocytes for neurodegenerative and psychiatric disorders. Published protocols for differentiation vary widely in the reported efficiency of target cell generation. Additionally, characterization of the cells by expression profile and functionality differs between studies and is often insufficient, leading to highly variable protocol outcomes. We have synthesized this information into a simple methodology that can be followed when performing or assessing differentiation techniques. Finally we propose three considerations for future research, including the use of physiological O2 conditions, three-dimensional co-culture systems and microfluidics to control feeding cycles and growth factor gradients. Following these guidelines will help researchers to ensure that robust and meaningful data is generated, enabling the full potential of stem cell differentiation for disease modeling and regenerative medicine.


Assuntos
Pesquisa Biomédica/métodos , Diferenciação Celular , Doenças Neurodegenerativas/terapia , Células-Tronco/citologia , Animais , Modelos Animais de Doenças , Humanos , Modelos Biológicos
6.
Acta Neuropathol ; 130(1): 119-29, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25778620

RESUMO

Knockout of genes encoding metabotropic glutamate receptor 5 (mGluR5) or its endogenous regulators, such as Norbin, induce a schizophrenia-like phenotype in rodents, suggesting dysregulation of mGluR5 in schizophrenia. Human genetic and pharmacological animal studies support this hypothesis, but no studies have explored mGluR5 dysfunction at the molecular level in the postmortem schizophrenia brain. We assessed mGluR5 mRNA and protein levels in the dorsolateral prefrontal cortex (DLPFC) using a large cohort of schizophrenia and control subjects (n = 37/group), and additionally measured protein levels of recently discovered mGluR5 endogenous regulators, Norbin (neurochondrin), Tamalin (GRASP-1), and Preso1 (FRMPD4), which regulate mGluR5 localization, internalization and signaling. While mGluR5 mRNA expression was unchanged, mGluR5 protein levels were significantly higher in schizophrenia subjects compared to controls (total: +22%; dimer: +54%; p < 0.001). Conversely, mGluR5 regulatory proteins were expressed at lower levels in schizophrenia subjects compared to controls (Norbin -37%, p < 0.001; Tamalin -30%, p = 0.084; Preso1 -29%, p = 0.001). mGluR5 protein was significantly associated with mGluR5 mRNA and mGluR5 endogenous regulators in control subjects, but these associations were lost in schizophrenia subjects. Lastly, there were no associations between protein measures and lifetime antipsychotic history in schizophrenia subjects. To confirm no antipsychotic influence, all proteins were measured in the prefrontal cortex of rats exposed to haloperidol or olanzapine; there were no effects of antipsychotic drug treatment on mGluR5, Norbin, Tamalin or Preso1. The results from our study provide compelling evidence that mGluR5 regulation is altered in schizophrenia, likely contributing to the altered glutamatergic signaling that is associated with the disorder.


Assuntos
Córtex Pré-Frontal/metabolismo , Receptor de Glutamato Metabotrópico 5/metabolismo , Esquizofrenia/metabolismo , Adolescente , Adulto , Idoso , Animais , Antipsicóticos/farmacologia , Proteínas de Transporte/metabolismo , Estudos de Coortes , Modelos Animais de Doenças , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Neuropeptídeos/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Esquizofrenia/tratamento farmacológico , Adulto Jovem
7.
Int J Neuropsychopharmacol ; 18(7): pyu114, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26478928

RESUMO

BACKGROUND: Substantial evidence from human post-mortem and genetic studies has linked the neurotrophic factor neuregulin 1 (NRG1) to the pathophysiology of schizophrenia. Genetic animal models and in vitro experiments have suggested that altered NRG1 signaling, rather than protein changes, contributes to the symptomatology of schizophrenia. However, little is known about the effect of NRG1 on schizophrenia-relevant behavior and neurotransmission (particularly GABAergic and glutamatergic) in adult animals. METHOD: To address this question, we treated adult mice with the extracellular signaling domain of NRG1 and assessed spontaneous locomotor activity and acoustic startle response, as well as extracellular GABA, glutamate, and glycine levels in the prefrontal cortex and hippocampus via microdialysis. Furthermore, we asked whether the effect of NRG1 would differ under schizophrenia-relevant impairments in mice and therefore co-treated mice with NRG1 and phencyclidine (PCP) (3 mg/kg). RESULTS: Acute intraventricularly- or systemically-injected NRG1 did not affect spontaneous behavior, but prevented PCP induced hyperlocomotion and deficits of prepulse inhibition. NRG1 retrodialysis (10 nM) reduced extracellular glutamate and glycine levels in the prefrontal cortex and hippocampus, and prevented PCP-induced increase in extracellular GABA levels in the hippocampus. CONCLUSION: With these results, we provide the first compelling in vivo evidence for the involvement of NRG1 signaling in schizophrenia-relevant behavior and neurotransmission in the adult nervous system, which highlight its treatment potential. Furthermore, the ability of NRG1 treatment to alter GABA, glutamate, and glycine levels in the presence of PCP also suggests that NRG1 signaling has the potential to alter disrupted neurotransmission in patients with schizophrenia.


Assuntos
Comportamento Animal/efeitos dos fármacos , Hipocampo/metabolismo , Neuregulina-1/farmacologia , Fenciclidina/farmacologia , Córtex Pré-Frontal/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo , Animais , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Antagonistas de Aminoácidos Excitatórios/farmacologia , Ácido Glutâmico/análise , Ácido Glutâmico/metabolismo , Glicina/análise , Glicina/metabolismo , Hipocampo/efeitos dos fármacos , Humanos , Injeções Intraventriculares , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microdiálise , Atividade Motora/efeitos dos fármacos , Neuregulina-1/administração & dosagem , Fenciclidina/administração & dosagem , Córtex Pré-Frontal/efeitos dos fármacos , Inibição Pré-Pulso/efeitos dos fármacos , Reflexo de Sobressalto/efeitos dos fármacos , Resultado do Tratamento , Ácido gama-Aminobutírico/análise
8.
Sci Rep ; 14(1): 13558, 2024 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-38866809

RESUMO

Longitudinal studies that continuously generate data enable the capture of temporal variations in experimentally observed parameters, facilitating the interpretation of results in a time-aware manner. We propose IL-VIS (incrementally learned visualizer), a new machine learning pipeline that incrementally learns and visualizes a progression trajectory representing the longitudinal changes in longitudinal studies. At each sampling time point in an experiment, IL-VIS generates a snapshot of the longitudinal process on the data observed thus far, a new feature that is beyond the reach of classical static models. We first verify the utility and correctness of IL-VIS using simulated data, for which the true progression trajectories are known. We find that it accurately captures and visualizes the trends and (dis)similarities between high-dimensional progression trajectories. We then apply IL-VIS to longitudinal multi-electrode array data from brain cortical organoids when exposed to different levels of quinolinic acid, a metabolite contributing to many neuroinflammatory diseases including Alzheimer's disease, and its blocking antibody. We uncover valuable insights into the organoids' electrophysiological maturation and response patterns over time under these conditions.


Assuntos
Aprendizado de Máquina , Estudos Longitudinais , Humanos , Organoides , Doença de Alzheimer/metabolismo , Encéfalo/fisiologia
9.
Heliyon ; 10(12): e32680, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975076

RESUMO

Repressor element-1 silencing transcription factor (REST) is a transcriptional repressor involved in neurodevelopment and neuroprotection. REST forms a complex with the REST corepressors, CoREST1, CoREST2, or CoREST3 (encoded by RCOR1, RCOR2, and RCOR3, respectively). Emerging evidence suggests that the CoREST family can target unique genes independently of REST, in various neural and glial cell types during different developmental stages. However, there is limited knowledge regarding the expression and function of the CoREST family in human neurodevelopment. To address this gap, we employed 2D and 3D human pluripotent stem cell (hPSC) models to investigate REST and RCOR gene expression levels. Our study revealed a significant increase in RCOR3 expression in glutamatergic cortical and GABAergic ventral forebrain neurons, as well as mature functional NGN2-induced neurons. Additionally, a simplified astrocyte transdifferentiation protocol resulted in a significant decrease in RCOR2 expression following differentiation. REST expression was notably reduced in mature neurons and cerebral organoids. In summary, our findings provide the first insights into the cell-type-specific expression patterns of RCOR genes in human neuronal and glial differentiation. Specifically, RCOR3 expression increases in neurons, while RCOR2 levels decrease in astrocytes. The dynamic expression patterns of REST and RCOR genes during hPSC neuronal and glial differentiation underscore the potential distinct roles played by REST and CoREST proteins in regulating the development of these cell types in humans.

10.
Clin Hemorheol Microcirc ; 83(1): 31-46, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35466932

RESUMO

AIM: To examine to what extent the high frame rate contrast-enhanced ultrasound (HiFR) diagnostic enables the conclusive diagnosis of liver changes with suspected malignancy. MATERIAL/METHODS: Ultrasound examinations were performed by an experienced examiner using a multifrequency probe (SC6-1) on a high-end ultrasound system (Resona 7, Mindray) to clarify liver changes that were unclear on the B-scan. A bolus of 1-2.4 ml of the Sulphur hexafluoride ultrasound microbubbles contrast agent SonoVue™ (Bracco SpA, Italy) was administered with DICOM storage of CEUS examinations from the early arterial phase (5-15 s) to the late phase (5-6 min). Based on the image files stored in the PACS, an independent reading was performed regarding image quality and finding-related diagnostic significance (0 not informative/non-diagnostic to 5 excellent image quality/confident diagnosis possible). References were clinical follow-up, if possible, comparison to promptly performed computed tomography or magnetic resonance imaging, in some cases also to histopathology. RESULTS: We examined 100 patients (42 women, 58 men, from 18 years to 90 years, mean 63±13 years) with different entities of focal and diffuse liver parenchymal changes, which could be detected in all cases with sufficient image quality with CEUS and with high image quality with HiFR-CEUS. Proportionally septate cysts were found in n = 19 cases, scars after hemihepatectomy with local reduced fat in n = 5 cases, scars after microwave ablation in n = 19 cases, hemangiomas in n = 9 cases, focal nodular hyperplasia in n = 8 cases, colorectal metastases in n = 15 cases, hepatocellular carcinoma (HCC) in n = 11 cases, Osler disease in n = 8 cases. The size of lesions ranged from 5 mm to 200 mm with a mean value of 33.1±27.8 mm. Conclusive diagnoses could be made by the experienced investigator in 97/100 cases with CEUS, confirmed by reference imaging, in parts by histopathology or follow-up. The image quality for HiFR CEUS was rated with a score of 3 to 5; 62 cases were assessed with an average of good (4 points), 27 cases with very good (5 points), and in 11 cases (3 points) still satisfactory despite aggravated acoustic conditions. The specificity of HIFR-CEUS was 97%, the sensitivity 97%, the positive predictive value 94%, the negative predictive value 99% and the accuracy 97%. CONCLUSION: HIFR-CEUS has demonstrated has demonstrated an improved image quality resulting in a high diagnostic accuracy. In the hands of an experienced investigator, HiFR-CEUS allows the assessment of focal and diffuse unclear liver parenchymal changes on B-scan and dynamic assessment of microcirculation in solid and vascular changes.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Feminino , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Cicatriz/patologia , Meios de Contraste , Ultrassonografia/métodos , Imageamento por Ressonância Magnética
11.
ACS Appl Bio Mater ; 6(11): 4603-4612, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37844275

RESUMO

In vitro cell models have undergone a shift from 2D models on glass slides to 3D models that better reflect the native 3D microenvironment. 3D bioprinting promises to progress the field by allowing the high-throughput production of reproducible cell-laden structures with high fidelity. The current stiffness range of printable matrices surrounding the cells that mimic the extracellular matrix environment remains limited. The work presented herein aims to expand the range of stiffnesses by utilizing a four-armed polyethylene glycol with maleimide-functionalized arms. The complementary cross-linkers comprised a matrix metalloprotease-degradable peptide and a four-armed thiolated polymer which were adjusted in ratio to tune the stiffness. The modularity of this system allows for a simple method of controlling stiffness and the addition of biological motifs. The application of this system in drop-on-demand printing is validated using MCF-7 cells, which were monitored for viability and proliferation. This study shows the potential of this system for the high-throughput investigation of the effects of stiffness and biological motif compositions in relation to cell behaviors.


Assuntos
Bioimpressão , Hidrogéis , Humanos , Matriz Extracelular , Vidro , Células MCF-7
12.
SLAS Technol ; 27(1): 32-38, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35058203

RESUMO

Advanced three dimensional cell culture techniques have been adopted in many laboratories to better model in vivo tissue by recapitulating multi-cellular architecture and the presence of extracellular matrix features. We describe here a 3D cell culture platform in a small molecule screening workflow that uses traditional biomarker and intracellular kinase end point assay readouts. By combining the high throughput bioprinter RASTRUM with the high throughput screening assay AlphaLISA, we demonstrate the utility of the protocol in 3D synthetic hydrogel cultures with breast cancer (MDA-MB-231 and MCF-7) and fibroblast cells. To establish and validate the workflow, we treated the breast cancer cultures with doxorubicin, while fibroblast cultures were stimulated with the pro-inflammatory lipopolysaccharide. 3D and 2D MDA-MB-231 cultures were equally susceptible to doxorubicin treatment, while showing opposite ERK phosphorylation changes. Doxorubicin readily entered embedded MCF-7 spheroids and markedly reduced intracellular GSK3ß phosphorylation. Furthermore, quantifying extracellular interleukin 6 levels showed a very similar activation profile for fibroblasts in 2D and 3D cultures, with 3D fibroblast networks being more resistant against the immune challenge. Through these validation experiments we demonstrate the full compatibility of the bioprinted 3D cell cultures with several widely-used 2D culture assays. The efficiency of the workflow, minimal culture handling, and applicability of traditional screening assays, demonstrates that advanced encapsulated 3D cell cultures can be used in 2D cell culture screening workflows, while providing a more holistic view on cell biology to increase the predictability to in vivo drug response.


Assuntos
Bioimpressão , Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Técnicas de Cultura de Células em Três Dimensões , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Descoberta de Drogas/métodos , Feminino , Humanos , Esferoides Celulares , Fluxo de Trabalho
13.
Biomater Sci ; 10(20): 5876-5887, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36149407

RESUMO

Understanding the underlying mechanisms of migration and metastasis is a key focus of cancer research. There is an urgent need to develop in vitro 3D tumor models that can mimic physiological cell-cell and cell-extracellular matrix interactions, with high reproducibility and that are suitable for high throughput (HTP) drug screening. Here, we developed a HTP 3D bioprinted migration model using a bespoke drop-on-demand bioprinting platform. This HTP platform coupled with tunable hydrogel systems enables (i) the rapid encapsulation of cancer cells within in vivo tumor mimicking matrices, (ii) in situ and real-time measurement of cell movement, (iii) detailed molecular analysis for the study of mechanisms underlying cell migration and invasion, and (iv) the identification of novel therapeutic options. This work demonstrates that this HTP 3D bioprinted cell migration platform has broad applications across quantitative cell and cancer biology as well as drug screening.


Assuntos
Bioimpressão , Neoplasias , Movimento Celular , Humanos , Hidrogéis , Impressão Tridimensional , Reprodutibilidade dos Testes
14.
Clin Hemorheol Microcirc ; 77(3): 303-310, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33337354

RESUMO

AIM: The aim of this study was to assess the success of irreversible electroporation (IRE) in prostate cancer and to differentiate between reactive changes and tumor. MATERIAL AND METHODS: This is a retrospective pilot study of 50 patients after irreversible electroporation (IRE) in prostate cancer between 50-79 years (mean age 65 years). Each patient received a transabdominal sonography using a 1-6 MHz convex matrix probe. Contrast-enhanced ultrasound (CEUS) was performed after i.v. bolus injection of 2.0 ml sulphur hexafluoride microbubbles. DICOM loops were continuously stored up to one minute. Parametric images were calculated by integrated perfusion analysis software. A comparison was drawn to a follow-up MRI six months after ablation. RESULTS: While 13 patients showed local recurrence, 37 patients were successfully treated, meaning no local recurrence within six months after ablation. 18 patients showed signs of prostatitis after IRE. Tumorous changes were visually characterized by dynamic early nodular hypervascularization with fast and high wash-in. Correspondingly, nodular red and yellow shades were seen in parametric imaging. All patients with remaining tumor were correctly identified with CEUS and parametric imaging. After IRE there is a relevant decrease in tumor microcirculation in all patients, as seen in more purple shades of the prostate. The sensitivity for detecting residual tumor with CEUS compared to MRI was 76%, the specificity was 81%. The corresponding positive predictive value (PPV) was 73% and the negative predictive value (NPV) was 83%. CONCLUSION: CEUS and parametric imaging enable a critical analysis of post-ablation defects after IRE for prostate cancer even with a transabdominal approach. Remaining tumor can be detected with the help of pseudo-colors.


Assuntos
Meios de Contraste/uso terapêutico , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/terapia , Ultrassonografia/métodos , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos
15.
Eur J Pharm Sci ; 163: 105876, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33989755

RESUMO

Successful preclinical drug testing relies in part on data generated using in vitro cell culture models that recapitulate the structure and function of tumours and other tissues in vivo. The growing evidence that 3D cell models can more accurately predict the efficacy of drug responses compared to traditionally utilised 2D cell culture systems has led to continuous scientific and technological advances that enable better physiologically representative in vitro modelling of in vivo tissues. This review will provide an overview of the utility of current 3D cell models from a drug screening perspective and explore the future of 3D cell models for drug discovery applications.


Assuntos
Técnicas de Cultura de Células , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos
16.
Stem Cell Res ; 42: 101701, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32006803

RESUMO

Dermal fibroblasts were donated by a 43 year old male patient with clinically diagnosed familial amyotrophic lateral sclerosis (ALS), carrying the SOD1E101G mutation. The induced pluripotent stem cell (iPSC) line UOWi007-A was generated using repeated mRNA transfections for pluripotency transcription factors Oct4, Klf4, Sox2, c-Myc, Lin28 and Nanog. The iPSCs carried the SOD1E101G genotype and had a normal karyotype, expressed expected pluripotency markers and were capable of in vitro differentiation into endodermal, mesodermal and ectodermal lineages. This iPSC line may be useful for investigating familial ALS resulting from a SOD1E101G mutation.


Assuntos
Esclerose Lateral Amiotrófica/genética , Fibroblastos/metabolismo , Superóxido Dismutase-1/genética , Linhagem Celular , Humanos , Fator 4 Semelhante a Kruppel , RNA Mensageiro/metabolismo
17.
Cells ; 9(9)2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887382

RESUMO

The study of neurodegenerative diseases using pluripotent stem cells requires new methods to assess neurodevelopment and neurodegeneration of specific neuronal subtypes. The cholinergic system, characterized by its use of the neurotransmitter acetylcholine, is one of the first to degenerate in Alzheimer's disease and is also affected in frontotemporal dementia. We developed a differentiation protocol to generate basal forebrain-like cholinergic neurons (BFCNs) from induced pluripotent stem cells (iPSCs) aided by the use of small molecule inhibitors and growth factors. Ten iPSC lines were successfully differentiated into BFCNs using this protocol. The neuronal cultures were characterised through RNA and protein expression, and functional analysis of neurons was confirmed by whole-cell patch clamp. We have developed a reliable protocol using only small molecule inhibitors and growth factors, while avoiding transfection or cell sorting methods, to achieve a BFCN culture that expresses the characteristic markers of cholinergic neurons.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Neurônios Colinérgicos/efeitos dos fármacos , Meios de Cultura/farmacologia , Corpos Embrioides/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Cultura Primária de Células/métodos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Prosencéfalo Basal/metabolismo , Prosencéfalo Basal/patologia , Benzamidas/farmacologia , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Linhagem Celular , Neurônios Colinérgicos/citologia , Neurônios Colinérgicos/metabolismo , Meios de Cultura/química , Dioxóis/farmacologia , Corpos Embrioides/citologia , Corpos Embrioides/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/farmacologia , Demência Frontotemporal/genética , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Fator 2 de Diferenciação de Crescimento/farmacologia , Proteínas Hedgehog/farmacologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Modelos Biológicos , Fator de Crescimento Neural/farmacologia , Técnicas de Patch-Clamp , Pirazóis/farmacologia , Pirimidinas/farmacologia , Fator de Crescimento Transformador beta/farmacologia
18.
Neuroscientist ; 26(5-6): 438-454, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32281909

RESUMO

Because our beliefs regarding our individuality, autonomy, and personhood are intimately bound up with our brains, there is a public fascination with cerebral organoids, the "mini-brain," the "brain in a dish". At the same time, the ethical issues around organoids are only now being explored. What are the prospects of using human cerebral organoids to better understand, treat, or prevent dementia? Will human organoids represent an improvement on the current, less-than-satisfactory, animal models? When considering these questions, two major issues arise. One is the general challenge associated with using any stem cell-generated preparation for in vitro modelling (challenges amplified when using organoids compared with simpler cell culture systems). The other relates to complexities associated with defining and understanding what we mean by the term "dementia." We discuss 10 puzzles, issues, and stumbling blocks to watch for in the quest to model "dementia in a dish."


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Demência/patologia , Células-Tronco Pluripotentes Induzidas/citologia , Organoides/citologia , Animais , Diferenciação Celular/fisiologia , Demência/fisiopatologia , Humanos
19.
RSC Adv ; 9(31): 17717-17725, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35520545

RESUMO

It has been suggested that electromagnetic fields could be used to differentiate neurons in culture but how to do this is not clear. We investigated the effect of external magnetic fields (DC and AC MF) on neuronal viability, differentiation, and neurite outgrowth of human SH-SY5Y neuroblastoma cells in vitro. A strong low frequency DC MF or a weak AC MF improved retinoic acid-mediated neuronal differentiation and increased neurite length, without any adverse effects on neuronal viability. Even in the absence of the conventional differentiation factor, retinoic acid, DC and AC MF promoted neurite outgrowth. No significant negative effect on cell viability was observed after MF exposure and the DC MF had greater effects on neurite length and branch number than AC MF. Thus, we have identified a novel, simple and cost-effective method that is easy to set up in any cell culture laboratory that can be used to efficiently differentiate neuronal-like cells, using a DC MF without the need for expensive reagents. This research provides a fresh approach to promote neurite outgrowth in a commonly used neuronal-like cell line model and may be applicable to neural stem cells or primary neurons.

20.
Stem Cell Res ; 40: 101530, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31445393

RESUMO

Dermal fibroblasts from a 59 year old male patient with amyotrophic lateral sclerosis (symptomatic at the time of collection), attributed to a mutation in the cyclin F gene (CCNFS621G), were reprogrammed using mRNA and microRNA-delivered OSKM factors to induced pluripotent stem cells (iPSCs). The generated iPSCs were confirmed pluripotent, expressing typical pluripotency markers and were capable of three germ layer differentiation. This is the first reported reprogramming of cells with a mutation in the cyclin F gene, and represents a novel resource for the study of amyotrophic lateral sclerosis.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Ciclinas/genética , Derme/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Esclerose Lateral Amiotrófica/genética , Diferenciação Celular , Linhagem Celular , Reprogramação Celular , Fibroblastos/citologia , Camadas Germinativas/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Cariótipo , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
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