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1.
Front Endocrinol (Lausanne) ; 15: 1368494, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38745948

RESUMO

Decidualisation, the process whereby endometrial stromal cells undergo morphological and functional transformation in preparation for trophoblast invasion, is often disrupted in women with polycystic ovary syndrome (PCOS) resulting in complications with pregnancy and/or infertility. The transcription factor Wilms tumour suppressor 1 (WT1) is a key regulator of the decidualization process, which is reduced in patients with PCOS, a complex condition characterized by increased expression of androgen receptor in endometrial cells and high presence of circulating androgens. Using genome-wide chromatin immunoprecipitation approaches on primary human endometrial stromal cells, we identify key genes regulated by WT1 during decidualization, including homeobox transcription factors which are important for regulating cell differentiation. Furthermore, we found that AR in PCOS patients binds to the same DNA regions as WT1 in samples from healthy endometrium, suggesting dysregulation of genes important to decidualisation pathways in PCOS endometrium due to competitive binding between WT1 and AR. Integrating RNA-seq and H3K4me3 and H3K27ac ChIP-seq metadata with our WT1/AR data, we identified a number of key genes involved in immune response and angiogenesis pathways that are dysregulated in PCOS patients. This is likely due to epigenetic alterations at distal enhancer regions allowing AR to recruit cofactors such as MAGEA11, and demonstrates the consequences of AR disruption of WT1 in PCOS endometrium.


Assuntos
Endométrio , Síndrome do Ovário Policístico , Receptores Androgênicos , Proteínas WT1 , Humanos , Feminino , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/patologia , Endométrio/metabolismo , Endométrio/patologia , Proteínas WT1/metabolismo , Proteínas WT1/genética , Receptores Androgênicos/metabolismo , Receptores Androgênicos/genética , Células Estromais/metabolismo , Células Estromais/patologia , Adulto , Sequências Reguladoras de Ácido Nucleico
2.
Stem Cells Transl Med ; 13(7): 693-710, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38584493

RESUMO

The environment created during embryogenesis contributes to reducing aberrations that drive structural malformations and tumorigenesis. In this study, we investigate the anti-cancer effect of mesenchymal stem cells (MSCs) derived from 2 different gestational tissues, the amniotic fluid (AF) and the chorionic villi (CV), with emphasis on their secretome. Transcriptomic analysis was performed on patient-derived AF- and CV-MSCs collected during prenatal diagnosis and identified both mRNAs and lncRNAs, involved in tissue homeostasis and inhibiting biological processes associated with the etiology of aggressive cancers while regulating immune pathways shown to be important in chronic disorders. Secretome enrichment analysis also identified soluble moieties involved in target cell regulation, tissue homeostasis, and cancer cell inhibition through the highlighted Wnt, TNF, and TGF-ß signaling pathways. Transcriptomic data were experimentally confirmed through in vitro assays, by evaluating the anti-cancer effect of the media conditioned by AF- and CV-MSCs and the exosomes derived from them on ovarian cancer cells, revealing inhibitory effects in 2D (by reducing cell viability and inducing apoptosis) and in 3D conditions (by negatively interfering with spheroid formation). These data provide molecular insights into the potential role of gestational tissues-derived MSCs as source of anti-cancer factors, paving the way for the development of therapeutics to create a pro-regenerative environment for tissue restoration following injury, disease, or against degenerative disorders.


Assuntos
Células-Tronco Mesenquimais , Humanos , Células-Tronco Mesenquimais/metabolismo , Feminino , Secretoma/metabolismo , Gravidez , Transcriptoma , Perfilação da Expressão Gênica , Exossomos/metabolismo , Vilosidades Coriônicas/metabolismo , Líquido Amniótico/metabolismo , Líquido Amniótico/citologia , Linhagem Celular Tumoral
3.
Stem Cell Res Ther ; 14(1): 265, 2023 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-37740230

RESUMO

BACKGROUND: Down syndrome (DS) clinical multisystem condition is generally considered the result of a genetic imbalance generated by the extra copy of chromosome 21. Recent discoveries, however, demonstrate that the molecular mechanisms activated in DS compared to euploid individuals are more complex than previously thought. Here, we utilize mesenchymal stem cells from chorionic villi (CV) to uncover the role of comprehensive functional genomics-based understanding of DS complexity. METHODS: Next-generation sequencing coupled with bioinformatic analysis was performed on CV obtained from women carrying fetuses with DS (DS-CV) to reveal specific genome-wide transcriptional changes compared to their euploid counterparts. Functional assays were carried out to confirm the biological processes identified as enriched in DS-CV compared to CV (i.e., cell cycle, proliferation features, immunosuppression and ROS production). RESULTS: Genes located on chromosomes other than the canonical 21 (Ch. 2, 6 and 22) are responsible for the impairment of life-essential pathways, including cell cycle regulation, innate immune response and reaction to external stimuli were found to be differentially expressed in DS-CV. Experimental validation confirmed the key role of the biological pathways regulated by those genes in the etiology of such a multisystem condition. CONCLUSIONS: NGS dataset generated in this study highlights the compromised functionality in the proliferative rate and in the innate response of DS-associated clinical conditions and identifies DS-CV as suitable tools for the development of specifically tailored, personalized intervention modalities.


Assuntos
Síndrome de Down , Humanos , Feminino , Síndrome de Down/genética , Vilosidades Coriônicas , Transcriptoma , Células-Tronco , Cromossomos
4.
Clin Epigenetics ; 15(1): 63, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060086

RESUMO

BACKGROUND: Ovarian cancer has a specific unmet clinical need, with a persistently poor 5-year survival rate observed in women with advanced stage disease warranting continued efforts to develop new treatment options. The amplification of BRD4 in a significant subset of high-grade serous ovarian carcinomas (HGSC) has led to the development of BET inhibitors (BETi) as promising antitumour agents that have subsequently been evaluated in phase I/II clinical trials. Here, we describe the molecular effects and ex vivo preclinical activities of i-BET858, a bivalent pan-BET inhibitor with proven in vivo BRD inhibitory activity. RESULTS: i-BET858 demonstrates enhanced cytotoxic activity compared with earlier generation BETis both in cell lines and primary cells derived from clinical samples of HGSC. At molecular level, i-BET858 triggered a bipartite transcriptional response, comprised of a 'core' network of genes commonly associated with BET inhibition in solid tumours, together with a unique i-BET858 gene signature. Mechanistically, i-BET858 elicited enhanced DNA damage, cell cycle arrest and apoptotic cell death compared to its predecessor i-BET151. CONCLUSIONS: Overall, our ex vivo and in vitro studies indicate that i-BET858 represents an optimal candidate to pursue further clinical validation for the treatment of HGSC.


Assuntos
Antineoplásicos , Carcinoma , Neoplasias Ovarianas , Feminino , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Metilação de DNA , Carcinoma Epitelial do Ovário/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Pontos de Checagem do Ciclo Celular , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma/genética , Apoptose , Dano ao DNA
5.
Br J Cancer ; 129(1): 163-174, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37120667

RESUMO

BACKGROUND: Epigenomic dysregulation has been linked to solid tumour malignancies, including ovarian cancers. Profiling of re-programmed enhancer locations associated with disease has the potential to improve stratification and thus therapeutic choices. Ovarian cancers are subdivided into histological subtypes that have significant molecular and clinical differences, with high-grade serous carcinoma representing the most common and aggressive subtype. METHODS: We interrogated the enhancer landscape(s) of normal ovary and subtype-specific ovarian cancer states using publicly available data. With an initial focus on H3K27ac histone mark, we developed a computational pipeline to predict drug compound activity based on epigenomic stratification. Lastly, we substantiated our predictions in vitro using patient-derived clinical samples and cell lines. RESULTS: Using our in silico approach, we highlighted recurrent and privative enhancer landscapes and identified the differential enrichment of a total of 164 transcription factors involved in 201 protein complexes across the subtypes. We pinpointed SNS-032 and EHMT2 inhibitors BIX-01294 and UNC0646 as therapeutic candidates in high-grade serous carcinoma, as well as probed the efficacy of specific inhibitors in vitro. CONCLUSION: Here, we report the first attempt to exploit ovarian cancer epigenomic landscapes for drug discovery. This computational pipeline holds enormous potential for translating epigenomic profiling into therapeutic leads.


Assuntos
Carcinoma , Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Humanos , Feminino , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/metabolismo , Antígenos de Histocompatibilidade/uso terapêutico , Histona-Lisina N-Metiltransferase
6.
Redox Biol ; 61: 102641, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36842241

RESUMO

At physiological levels, the trace element selenium plays a key role in redox reactions through the incorporation of selenocysteine in antioxidant enzymes. Selenium has also been evaluated as a potential anti-cancer agent, where selenium nanoparticles have proven effective, and are well tolerated in vivo at doses that are toxic as soluble Se. The use of such nanoparticles, coated with either serum albumin or the naturally occurring alkaline polysaccharide chitosan, also serves to enhance biocompatibility and bioavailability. Here we demonstrate a novel role for selenium in regulating histone methylation in ovarian cancer cell models treated with inorganic selenium nanoparticles coated with serum albumin or chitosan. As well as inducing thioredoxin reductase expression, ROS activity and cancer cell cytotoxicity, coated nanoparticles caused significant increases in histone methylation. Specifically, selenium nanoparticles triggered an increase in the methylation of histone 3 at lysines K9 and K27, histone marks involved in both the activation and repression of gene expression, thus suggesting a fundamental role for selenium in these epigenetic processes. This direct function was confirmed using chemical inhibitors of the histone lysine methyltransferases EZH2 (H3K27) and G9a/EHMT2 (H3K9), both of which blocked the effect of selenium on histone methylation. This novel role for selenium supports a distinct function in histone methylation that occurs due to a decrease in S-adenosylhomocysteine, an endogenous inhibitor of lysine methyltransferases, the metabolic product of methyl-group transfer from S-adenosylmethionine in the one-carbon metabolism pathway. These observations provide important new insights into the action of selenium nanoparticles. It is now important to consider both the classic antioxidant and novel histone methylation effects of this key redox element in its development in cancer therapy and other applications.


Assuntos
Quitosana , Selênio , Histonas/metabolismo , Metilação , Selênio/metabolismo , Lisina/metabolismo , S-Adenosil-Homocisteína/metabolismo , Antioxidantes/metabolismo , Quitosana/metabolismo , Histona-Lisina N-Metiltransferase/genética
7.
Front Cell Infect Microbiol ; 13: 1122340, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36798083

RESUMO

Background: The increasing prevalence of invasive fungal infections in immuno-compromised patients is a considerable cause of morbidity and mortality. With the rapid emergence of antifungal resistance and an inadequate pipeline of new therapies, novel treatment strategies are now urgently required. Methods: The antifungal activity of the alginate oligosaccharide OligoG in conjunction with nystatin was tested against a range of Candida spp. (C. albicans, C. glabrata, C. parapsilosis, C. auris, C. tropicalis and C. dubliniensis), in both planktonic and biofilm assays, to determine its potential clinical utility to enhance the treatment of candidal infections. The effect of OligoG (0-6%) ± nystatin on Candida spp. was examined in minimum inhibitory concentration (MIC) and growth curve assays. Antifungal effects of OligoG and nystatin treatment on biofilm formation and disruption were characterized using confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM) and ATP cellular viability assays. Effects on the cell membrane were determined using permeability assays and transmission electron microscopy (TEM). Results: MIC and growth curve assays demonstrated the synergistic effects of OligoG (0-6%) with nystatin, resulting in an up to 32-fold reduction in MIC, and a significant reduction in the growth of C. parapsilosis and C. auris (minimum significant difference = 0.2 and 0.12 respectively). CLSM and SEM imaging demonstrated that the combination treatment of OligoG (4%) with nystatin (1 µg/ml) resulted in significant inhibition of candidal biofilm formation on glass and clinical grade silicone surfaces (p < 0.001), with increased cell death (p < 0.0001). The ATP biofilm disruption assay demonstrated a significant reduction in cell viability with OligoG (4%) alone and the combined OligoG/nystatin (MIC value) treatment (p < 0.04) for all Candida strains tested. TEM studies revealed the combined OligoG/nystatin treatment induced structural reorganization of the Candida cell membrane, with increased permeability when compared to the untreated control (p < 0.001). Conclusions: Antimicrobial synergy between OligoG and nystatin against Candida spp. highlights the potential utility of this combination therapy in the prevention and topical treatment of candidal biofilm infections, to overcome the inherent tolerance of biofilm structures to antifungal agents.


Assuntos
Antifúngicos , Candidíase , Humanos , Antifúngicos/farmacologia , Antifúngicos/química , Nistatina/farmacologia , Nistatina/metabolismo , Alginatos/farmacologia , Alginatos/química , Alginatos/metabolismo , Candida , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Candida tropicalis , Candida glabrata , Biofilmes , Oligossacarídeos/farmacologia , Oligossacarídeos/química , Trifosfato de Adenosina/metabolismo , Testes de Sensibilidade Microbiana
8.
Front Oncol ; 12: 1014280, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36505806

RESUMO

Background: Ovarian cancer (OC) is amongst the most lethal of common cancers in women. Lacking in specific symptoms in the early stages, OC is predominantly diagnosed late when the disease has undergone metastatic spread and chemotherapy is relied on to prolong life. Platinum-based therapies are preferred and although many tumors respond initially, the emergence of platinum-resistance occurs in the majority of cases after which prognosis is very poor. Upregulation of DNA damage pathways is a common feature of platinum resistance in OC with cyclin dependent kinases (CDKs) serving as key regulators of this process and suggesting that CDK inhibitors (CDKis) could be effective tools in the treatment of platinum resistant and refractory OC. Aim: The aim of this study was to evaluate the efficacy of CDKis in platinum resistant OC models and serve as a predictor of potential clinical utility. Methods: The efficacy of CDKi, dinaciclib, was determined in wildtype and platinum resistant cell line pairs representing different OC subtypes. In addition, dinaciclib was evaluated in primary cells isolated from platinum-sensitive and platinum-refractory tumors to increase the clinical relevance of the study. Results and conclusions: Dinaciclib proved highly efficacious in OC cell lines and primary cells, which were over a thousand-fold more sensitive to the CDKi than to cisplatin. Furthermore, cisplatin resistance in these cells did not influence sensitivity to dinaciclib and the two drugs combined additively in both platinum-sensitive and platinum-resistant OC cells suggesting a potential role for pan-CDKis (CDKis targeting multiple CDKs), such as dinaciclib, in the treatment of advanced and platinum-resistant OC.

9.
Sci Transl Med ; 14(662): eabn3758, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36103515

RESUMO

The management of antibiotic-resistant, bacterial biofilm infections in chronic skin wounds is an increasing clinical challenge. Despite advances in diagnosis, many patients do not derive benefit from current anti-infective/antibiotic therapies. Here, we report a novel class of naturally occurring and semisynthetic epoxy-tiglianes, derived from the Queensland blushwood tree (Fontainea picrosperma), and demonstrate their antimicrobial activity (modifying bacterial growth and inducing biofilm disruption), with structure/activity relationships established against important human pathogens. In vitro, the lead candidate EBC-1013 stimulated protein kinase C (PKC)-dependent neutrophil reactive oxygen species (ROS) induction and NETosis and increased expression of wound healing-associated cytokines, chemokines, and antimicrobial peptides in keratinocytes and fibroblasts. In vivo, topical EBC-1013 induced rapid resolution of infection with increased matrix remodeling in acute thermal injuries in calves. In chronically infected diabetic mouse wounds, treatment induced cytokine/chemokine production, inflammatory cell recruitment, and complete healing (in six of seven wounds) with ordered keratinocyte differentiation. These results highlight a nonantibiotic approach involving contrasting, orthogonal mechanisms of action combining targeted biofilm disruption and innate immune induction in the treatment of chronic wounds.


Assuntos
Forbóis , Animais , Antibacterianos/farmacologia , Biofilmes , Bovinos , Humanos , Queratinócitos , Camundongos , Cicatrização
10.
Adv Healthc Mater ; 11(1): e2101127, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34662505

RESUMO

Focal chondral lesions of the knee are the most frequent type of trauma in younger patients and are associated with a high risk of developing early posttraumatic osteoarthritis. The only current clinical solutions include microfracture, osteochondral grafting, and autologous chondrocyte implantation. Cartilage tissue engineering based on biomimetic scaffolds has become an appealing strategy to repair cartilage defects. Here, a chondrogenic collagen-chondroitin sulfate scaffold is tested in an orthotopic Lapine in vivo model to understand the beneficial effects of the immunomodulatory biomaterial on the full chondral defect. Using a combination of noninvasive imaging techniques, histological and whole transcriptome analysis, the scaffolds are shown to enhance the formation of cartilaginous tissue and suppression of host cartilage degeneration, while also supporting tissue integration and increased tissue regeneration over a 12 weeks recovery period. The results presented suggest that biomimetic materials could be a clinical solution for cartilage tissue repair, due to their ability to modulate the immune environment in favor of regenerative processes and suppression of cartilage degeneration.


Assuntos
Cartilagem Articular , Biomimética , Condrócitos , Condrogênese , Humanos , Engenharia Tecidual , Alicerces Teciduais
11.
Int J Mol Sci ; 22(18)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34576261

RESUMO

From the development of self-aggregating, scaffold-free multicellular spheroids to the inclusion of scaffold systems, 3D models have progressively increased in complexity to better mimic native tissues. The inclusion of a third dimension in cancer models allows researchers to zoom out from a significant but limited cancer cell research approach to a wider investigation of the tumor microenvironment. This model can include multiple cell types and many elements from the extracellular matrix (ECM), which provides mechanical support for the tissue, mediates cell-microenvironment interactions, and plays a key role in cancer cell invasion. Both biochemical and biophysical signals from the extracellular space strongly influence cell fate, the epigenetic landscape, and gene expression. Specifically, a detailed mechanistic understanding of tumor cell-ECM interactions, especially during cancer invasion, is lacking. In this review, we focus on the latest achievements in the study of ECM biomechanics and mechanosensing in cancer on 3D scaffold-based and scaffold-free models, focusing on each platform's level of complexity, up-to-date mechanical tests performed, limitations, and potential for further improvements.


Assuntos
Matriz Extracelular/patologia , Imageamento Tridimensional , Neoplasias/patologia , Animais , Materiais Biocompatíveis/química , Fenômenos Biomecânicos , Biofísica , Velocidade do Fluxo Sanguíneo , Linhagem Celular Tumoral , Humanos , Hidrogéis/química , Camundongos , Microfluídica , Modelos Biológicos , Organoides , Porosidade , Transdução de Sinais , Esferoides Celulares , Análise Serial de Tecidos , Engenharia Tecidual/instrumentação , Alicerces Teciduais , Microambiente Tumoral
12.
Mar Drugs ; 19(8)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34436244

RESUMO

Osteoarthritis (OA) is a multifactorial disease leading to degeneration of articular cartilage, causing morbidity in approximately 8.5 million of the UK population. As the dense extracellular matrix of articular cartilage is primarily composed of collagen, cartilage repair strategies have exploited the biocompatibility and mechanical strength of bovine and porcine collagen to produce robust scaffolds for procedures such as matrix-induced chondrocyte implantation (MACI). However, mammalian sourced collagens pose safety risks such as bovine spongiform encephalopathy, transmissible spongiform encephalopathy and possible transmission of viral vectors. This study characterised a non-mammalian jellyfish (Rhizostoma pulmo) collagen as an alternative, safer source in scaffold production for clinical use. Jellyfish collagen demonstrated comparable scaffold structural properties and stability when compared to mammalian collagen. Jellyfish collagen also displayed comparable immunogenic responses (platelet and leukocyte activation/cell death) and cytokine release profile in comparison to mammalian collagen in vitro. Further histological analysis of jellyfish collagen revealed bovine chondroprogenitor cell invasion and proliferation in the scaffold structures, where the scaffold supported enhanced chondrogenesis in the presence of TGFß1. This study highlights the potential of jellyfish collagen as a safe and biocompatible biomaterial for both OA repair and further regenerative medicine applications.


Assuntos
Organismos Aquáticos/química , Materiais Biocompatíveis/química , Condrogênese/efeitos dos fármacos , Colágeno/química , Osteoartrite/terapia , Cifozoários , Alicerces Teciduais/química , Animais , Colágeno/farmacologia , Humanos , Engenharia Tecidual
13.
Cancers (Basel) ; 13(5)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800911

RESUMO

Endometrial cancer (EC) is the sixth most prevalent female cancer globally and although high rates of success are achieved when diagnosed at an early stage, the 5-year survival rate for cancers diagnosed at Stages II-IV is below 50%. Improving patient outcomes will necessitate the introduction of novel therapies to the clinic. Pan-cyclin-dependent kinase inhibitors (CDKis) have been explored as therapies for a range of cancers due to their ability to simultaneously target multiple key cellular processes, such as cell cycle progression, transcription, and DNA repair. Few studies, however, have reported on their potential for the treatment of EC. Herein, we examined the effects of the pan-CDKi dinaciclib in primary cells isolated directly from tumors and EC cell lines. Dinaciclib was shown to elicit a bimodal action in EC cell lines, disrupting both cell cycle progression and phosphorylation of the RNA polymerase carboxy terminal domain, with a concomitant reduction in Bcl-2 expression. Furthermore, the therapeutic potential of combining dinaciclib and cisplatin was explored, with the drugs demonstrating synergy at specific doses in Type I and Type II EC cell lines. Together, these results highlight the potential of dinaciclib for use as an effective EC therapy.

14.
Nanoscale ; 13(12): 6129-6141, 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33729236

RESUMO

Extracellular vesicles (EVs) are studied extensively as natural biomolecular shuttles and for their diagnostic and therapeutic potential. This exponential rise in interest has highlighted the need for highly robust and reproducible approaches for EV characterisation. Here we optimise quantitative nanomechanical tools and demonstrate the advantages of EV population screening by atomic force microscopy (AFM). Our high-content informatics analytical tools are made available for use by the EV community for widespread, standardised determination of structural stability. Ultracentrifugation (UC) and sonication, the common mechanical techniques used for EV isolation and loading respectively, are used to demonstrate the utility of optimised PeakForce-Quantitative Nano Mechanics (PF-QNM) analysis. EVs produced at an industrial scale exhibited biochemical and biomechanical alterations after exposure to these common techniques. UC resulted in slight increases in physical dimensions, and decreased EV adhesion concurrent with a decrease in CD63 content. Sonicated EVs exhibited significantly reduced levels of CD81, a decrease in size, increased Young's modulus and decreased adhesive force. These biomechanical and biochemical changes highlight the effect of EV sample preparation techniques on critical properties linked to EV cellular uptake and biological function. PF-QNM offers significant additional information about the structural information of EVs following their purification and downstream processing, and the analytical tools will ensure consistency of analysis of AFM data by the EV community, as this technique continues to become more widely implemented.


Assuntos
Vesículas Extracelulares , Módulo de Elasticidade , Fenômenos Mecânicos , Microscopia de Força Atômica , Ultracentrifugação
15.
J Nanobiotechnology ; 19(1): 50, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33596915

RESUMO

BACKGROUND: Sialyl-Lewis X/L-selectin high affinity binding interactions between transmembrane O-glycosylated mucins proteins and the embryo have been implicated in implantation processes within the human reproductive system. However, the adhesive properties of these mucins at the endometrial cell surface are difficult to resolve due to known discrepancies between in vivo models and the human reproductive system and a lack of sensitivity in current in vitro models. To overcome these limitations, an in vitro model of the human endometrial epithelial was interrogated with single molecule force spectroscopy (SMFS) to delineate the molecular configurations of mucin proteins that mediate the high affinity L-selectin binding required for human embryo implantation. RESULTS: This study reveals that MUC1 contributes to both the intrinsic and extrinsic adhesive properties of the HEC-1 cellular surface. High expression of MUC1 on the cell surface led to a significantly increased intrinsic adhesion force (148 pN vs. 271 pN, p < 0.001), whereas this adhesion force was significantly reduced (271 pN vs. 118 pN, p < 0.001) following siRNA mediated MUC1 ablation. Whilst high expression of MUC1 displaying elevated glycosylation led to strong extrinsic (> 400 pN) L-selectin binding at the cell surface, low expression of MUC1 with reduced glycosylation resulted in significantly less (≤200 pN) binding events. CONCLUSIONS: An optimal level of MUC1 together with highly glycosylated decoration of the protein is critical for high affinity L-selectin binding. This study demonstrates that MUC1 contributes to cellular adhesive properties which may function to facilitate trophoblast binding to the endometrial cell surface through the L-selectin/sialyl-Lewis x adhesion system subsequent to implantation.


Assuntos
Selectina L/química , Selectina L/metabolismo , Mucina-1/química , Mucina-1/metabolismo , Biofísica , Adesão Celular , Linhagem Celular , Células Epiteliais , Glicosilação , Humanos , Mucinas/metabolismo , Imagem Individual de Molécula
16.
Front Bioinform ; 1: 662210, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36303763

RESUMO

Many chemotherapeutic drugs target cell processes in specific cell cycle phases. Determining the specific phases targeted is key to understanding drug mechanism of action and efficacy against specific cancer types. Flow cytometry experiments, combined with cell cycle phase and division round specific staining, can be used to quantify the current cell cycle phase and number of mitotic events of each cell within a population. However, quantification of cell interphase times and the efficacy of cytotoxic drugs targeting specific cell cycle phases cannot be determined directly. We present a data driven computational cell population model for interpreting experimental results, where in-silico populations are initialized to match observable results from experimental populations. A two-stage approach is used to determine the efficacy of cytotoxic drugs in blocking cell-cycle phase transitions. In the first stage, our model is fitted to experimental multi-parameter flow cytometry results from untreated cell populations to identify parameters defining probability density functions for phase transitions. In the second stage, we introduce a blocking routine to the model which blocks a percentage of attempted transitions between cell-cycle phases due to therapeutic treatment. The resulting model closely matches the percentage of cells from experiment in each cell-cycle phase and division round. From untreated cell populations, interphase and intermitotic times can be inferred. We then identify the specific cell-cycle phases that cytotoxic compounds target and quantify the percentages of cell transitions that are blocked compared with the untreated population, which will lead to improved understanding of drug efficacy and mechanism of action.

17.
Sci Rep ; 10(1): 16610, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024130

RESUMO

Cartilage repair in osteoarthritic patients remains a challenge. Identifying resident or donor stem/progenitor cell populations is crucial for augmenting the low intrinsic repair potential of hyaline cartilage. Furthermore, mediating the interaction between these cells and the local immunogenic environment is thought to be critical for long term repair and regeneration. In this study we propose articular cartilage progenitor/stem cells (CPSC) as a valid alternative to bone marrow-derived mesenchymal stem cells (BMMSC) for cartilage repair strategies after trauma. Similar to BMMSC, CPSC isolated from osteoarthritic patients express stem cell markers and have chondrogenic, osteogenic, and adipogenic differentiation ability. In an in vitro 2D setting, CPSC show higher expression of SPP1 and LEP, markers of osteogenic and adipogenic differentiation, respectively. CPSC also display a higher commitment toward chondrogenesis as demonstrated by a higher expression of ACAN. BMMSC and CPSC were cultured in vitro using a previously established collagen-chondroitin sulfate 3D scaffold. The scaffold mimics the cartilage niche, allowing both cell populations to maintain their stem cell features and improve their immunosuppressive potential, demonstrated by the inhibition of activated PBMC proliferation in a co-culture setting. As a result, this study suggests articular cartilage derived-CPSC can be used as a novel tool for cellular and acellular regenerative medicine approaches for osteoarthritis (OA). In addition, the benefit of utilizing a biomimetic acellular scaffold as an advanced 3D culture system to more accurately mimic the physiological environment is demonstrated.


Assuntos
Cartilagem Articular/citologia , Cartilagem Articular/fisiologia , Técnicas de Cultura de Células/métodos , Condrogênese/genética , Condrogênese/imunologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Expressão Gênica/genética , Células-Tronco/fisiologia , Agrecanas/genética , Agrecanas/metabolismo , Células Cultivadas , Condrogênese/fisiologia , Humanos , Leptina/genética , Leptina/metabolismo , Osteoartrite/genética , Osteoartrite/fisiopatologia , Osteopontina/genética , Osteopontina/metabolismo , Alicerces Teciduais
18.
Nanomedicine ; 29: 102258, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32615338

RESUMO

High dose selenium acts as a cytotoxic agent, with potential applications in cancer treatment. However, clinical trials have failed to show any chemotherapeutic value of selenium at safe and tolerated doses (<90 µg/day). To enable the successful exploitation of selenium for cancer treatment, we evaluated inorganic selenium nanoparticles (SeNP), and found them effective in inhibiting ovarian cancer cell growth. In both SKOV-3 and OVCAR-3 ovarian cancer cell types SeNP treatment resulted in significant cytotoxicity. The two cell types displayed contrasting nanomechanical responses to SeNPs, with decreased surface roughness and membrane stiffness, characteristics of OVCAR-3 cell death. In SKOV-3, cell membrane surface roughness and stiffness increased, both properties associated with decreased metastatic potential. The beneficial effects of SeNPs on ovarian cancer cell death appear cell type dependent, and due to their low in vivo toxicity offer an exciting opportunity for future cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Nanopartículas Metálicas/química , Neoplasias Ovarianas/tratamento farmacológico , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Fenômenos Biomecânicos , Carcinoma Epitelial do Ovário/metabolismo , Carcinoma Epitelial do Ovário/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Selênio/química , Selênio/farmacologia
19.
Stem Cells Dev ; 29(14): 882-894, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32364057

RESUMO

Articular cartilage contains a subpopulation of tissue-specific progenitors that are an ideal cell type for cell therapies and generating neocartilage for tissue engineering applications. However, it is unclear whether the standard chondrogenic medium using transforming growth factor beta (TGFß) isoforms is optimal to differentiate these cells. We therefore used pellet culture to screen progenitors from immature bovine articular cartilage with a number of chondrogenic factors and discovered that bone morphogenetic protein-9 (BMP9) precociously induces their differentiation. This difference was apparent with toluidine blue staining and confirmed by biochemical and transcriptional analyses with BMP9-treated progenitors exhibiting 11-fold and 5-fold greater aggrecan and collagen type II (COL2A1) gene expression than TGFß1-treated progenitors. Quantitative gene expression analysis over 14 days highlighted the rapid and phased nature of BMP9-induced chondrogenesis with sequential activation of aggrecan then collagen type II, and negligible collagen type X gene expression. The extracellular matrix of TGFß1-treated progenitors analyzed using atomic force microscopy was fibrillar and stiff whist BMP9-induced matrix of cells more compliant and correspondingly less fibrillar. Polarized light microscopy revealed an annular pattern of collagen fibril deposition typified by TGFß1-treated pellets, whereas BMP9-treated pellets displayed a birefringence pattern that was more anisotropic. Remarkably, differentiated immature chondrocytes incubated as high-density cultures in vitro with BMP9 generated a pronounced anisotropic organization of collagen fibrils indistinguishable from mature adult articular cartilage, with cells in deeper zones arranged in columnar manner. This contrasted with cells grown with TGFß1, where a concentric pattern of collagen fibrils was visualized within tissue pellets. In summary, BMP9 is a potent chondrogenic factor for articular cartilage progenitors and is also capable of inducing morphogenesis of adult-like cartilage, a highly desirable attribute for in vitro tissue-engineered cartilage.


Assuntos
Cartilagem Articular/citologia , Condrogênese , Fator 2 de Diferenciação de Crescimento/metabolismo , Células-Tronco/citologia , Animais , Bovinos , Células Cultivadas , Colágeno/metabolismo , Regulação da Expressão Gênica , Fator 2 de Diferenciação de Crescimento/genética , Hidroxiprolina/metabolismo
20.
Biosens Bioelectron ; 157: 112144, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32250927

RESUMO

In vitro fertilization (IVF) is the most common assisted reproductive technology used to treat infertility. Embryo selection for transfer in IVF cycles relies on the morphological evaluation by embryologists, either by conventional microscopic assessment or more recently by time-lapse imaging systems. Despite the introduction of time-lapse imaging improvements in IVF success rates have failed to materialize, therefore alternative approaches are needed. Recent studies have shown that embryos resulting in successful pregnancy differ in their secretome and metabolism compared to embryos that fail to implant, suggesting that molecular analysis of embryo culture medium could assist in non-invasive single embryo selection. However, this approach has yet to be adopted clinically due to the lack of appropriate highly sensitive screening technologies needed to assess volume-limited samples. Here we report the detection of hCGß, IL-8 and TNFα from conditioned culture media of single human embryos using electrochemical impedance spectroscopy. The impedimetric immunosensors revealed that morphologically non-viable embryos produce higher levels of IL-8 and TNFα, associated with abnormal cell division and cell death, respectively. More importantly, hCGß detection was able to discriminate apparently morphologically identical viable embryos. This work brings an objective dimension to embryo selection, which could overcome the major limitations of morphology-based embryo selection for implantation. Future work should include the validation of these biomarkers in a large patient cohort.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/análise , Meios de Cultivo Condicionados/metabolismo , Embrião de Mamíferos/metabolismo , Interleucina-8/análise , Fator de Necrose Tumoral alfa/análise , Técnicas Biossensoriais/métodos , Linhagem Celular , Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Meios de Cultivo Condicionados/análise , Técnicas de Cultura Embrionária , Implantação do Embrião , Desenvolvimento Embrionário , Feminino , Fertilização in vitro , Humanos , Imunoensaio/métodos , Interleucina-8/metabolismo , Gravidez , Fator de Necrose Tumoral alfa/metabolismo
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