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1.
Front Neurosci ; 17: 1057551, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37706156

RESUMO

Introduction: Conductive hearing loss (CHL) attenuates the ability to transmit air conducted sounds to the ear. In humans, severe hearing loss is often accompanied by alterations to other neural systems, such as the vestibular system; however, the inter-relations are not well understood. The overall goal of this study was to assess vestibular-related functioning proxies in a rat CHL model. Methods: Male Sprague-Dawley rats (N=134, 250g, 2months old) were used in a CHL model which produced a >20dB threshold shift induced by tympanic membrane puncture. Auditory brainstem response (ABRs) recordings were used to determine threshold depth at different times before and after CHL. ABR threshold depths were assessed both manually and by an automated ABR machine learning algorithm. Vestibular-related functioning proxy assessment was performed using the rotarod, balance beam, elevator vertical motion (EVM) and Ferris-wheel rotation (FWR) assays. Results: The Pre-CHL (control) threshold depth was 27.92dB±11.58dB compared to the Post-CHL threshold depth of 50.69dB±13.98dB (mean±SD) across the frequencies tested. The automated ABR machine learning algorithm determined the following threshold depths: Pre-CHL=24.3dB, Post-CHL same day=56dB, Post-CHL 7 days=41.16dB, and Post-CHL 1 month=32.5dB across the frequencies assessed (1, 2, 4, 8, 16, and 32kHz). Rotarod assessment of motor function was not significantly different between pre and post-CHL (~1week) rats for time duration (sec) or speed (RPM), albeit the former had a small effect size difference. Balance beam time to transverse was significantly longer for post-CHL rats, likely indicating a change in motor coordination. Further, failure to cross was only noted for CHL rats. The defection count was significantly reduced for CHL rats compared to control rats following FWR, but not EVM. The total distance traveled during open-field examination after EVM was significantly different between control and CHL rats, but not for FWR. The EVM is associated with linear acceleration (acting in the vertical plane: up-down) stimulating the saccule, while the FWR is associated with angular acceleration (centrifugal rotation about a circular axis) stimulating both otolith organs and semicircular canals; therefore, the difference in results could reflect the specific vestibular-organ functional role. Discussion: Less movement (EVM) and increase time to transverse (balance beam) may be associated with anxiety and alterations to defecation patterns (FWR) may result from autonomic disturbances due to the impact of hearing loss. In this regard, vestibulomotor deficits resulting in changes in balance and motion could be attributed to comodulation of auditory and vestibular functioning. Future studies should manipulate vestibular functioning directly in rats with CHL.

2.
Hepatology ; 78(6): 1711-1726, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36630996

RESUMO

BACKGROUND AND AIMS: HCC is an aggressive disease with poor clinical outcome. Understanding the mechanisms that drive cancer stemness, which we now know is the root cause of therapy failure and tumor recurrence, is fundamental for designing improved therapeutic strategies. This study aims to identify molecular players specific to CD133 + HCC to better design drugs that can precisely interfere with cancer stem cells but not normal stem cell function. APPROACH AND RESULTS: Transcriptome profiling comparison of epithelial-specific "normal" CD133 + cells isolated from fetal and regenerating liver against "HCC" CD133 + cells isolated from proto-oncogene-driven and inflammation-associated HCC revealed preferential overexpression of SERPINA12 in HCC but not fetal and regenerating liver CD133 + cells. SERPINA12 upregulation in HCC is tightly associated with aggressive clinical and stemness features, including survival, tumor stage, cirrhosis, and stemness signatures. Enrichment of SERPINA12 in HCC is mediated by promoter binding of the well-recognized ß-catenin effector TCF7L2 to drive SERPINA12 transcriptional activity. Functional characterization identified a unique and novel role of endogenous SERPINA12 in promoting self-renewal, therapy resistance, and metastatic abilities. Mechanistically, SERPINA12 functioned through binding to GRP78, resulting in a hyperactivated AKT/GSK3ß/ß-catenin signaling cascade, forming a positive feed-forward loop. Intravenous administration of rAAV8-shSERPINA12 sensitized HCC cells to sorafenib and impeded the cancer stem cell subset in an immunocompetent HCC mouse model. CONCLUSIONS: Collectively, our findings revealed that SERPINA12 is preferentially overexpressed in epithelial HCC CD133 + cells and is a key contributor to HCC initiation and progression by driving an AKT/ß-catenin feed-forward loop.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , beta Catenina/metabolismo , Linhagem Celular Tumoral , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/metabolismo , Proliferação de Células
3.
JHEP Rep ; 5(1): 100604, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36440258

RESUMO

Background & Aims: SCY1-like pseudokinase 3 (SCYL3) was identified as a binding partner of ezrin, implicating it in metastasis. However, the clinical relevance and functional role of SCYL3 in cancer remain uncharacterized. In this study, we aimed to elucidate the role of SCYL3 in the progression of hepatocellular carcinoma (HCC). Methods: The clinical significance of SCYL3 in HCC was evaluated in publicly available datasets and by qPCR analysis of an in-house HCC cohort. The functional significance and mechanistic consequences of SCYL3 were examined in SCYL3-knockdown/overexpressing HCC cells. In vivo tumor progression was evaluated in Tp53 KO/c-Myc OE mice using the sleeping beauty transposon system. Potential downstream pathways were investigated by co-immunoprecipitation, western blotting analysis and immunofluorescence staining. Results: SCYL3 is often overexpressed in HCC; it is preferentially expressed in metastatic human HCC tumors and is associated with worse patient survival. Suppression of SCYL3 in HCC cells attenuated cell proliferation and migration as well as in vivo metastasis. Intriguingly, endogenous SCYL3 overexpression increased tumor development and metastasis in Tp53 KO/c-Myc OE mice. Mechanistic investigations revealed that SCYL3 physically binds and regulates the stability and transactivating activity of ROCK2 (Rho kinase 2) via its C-terminal domain, leading to the increased formation of actin stress fibers and focal adhesions. Conclusions: These findings reveal that SCYL3 plays a critical role in promoting the progression of HCC and have implications for developing new therapeutic strategies to tackle metastatic HCC. Impact and implications: SCYL3 was first reported to be a binding partner of a metastasis-related gene, ezrin. To date, the clinical relevance and functional role of SCYL3 in cancer remain uncharacterized. Herein, we uncover its crucial role in liver cancer progression. We show that it physically binds and regulates the stability and transactivating activity of ROCK2 leading to HCC tumor progression. Our data provide mechanistic insight that SCYL3-mediated ROCK2 protein stability plays a pivotal role in growth and metastasis of HCC cells. Targeting SCYL3/ROCK2 signaling cascade may be a novel therapeutic strategy for treatment of HCC patients.

4.
Bipolar Disord ; 25(1): 56-65, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36409044

RESUMO

BACKGROUND: The use of lithium during breast-feeding has not been comprehensively investigated in humans due to concerns about lithium toxicity. PROCEDURE: We analyzed lithium in the kidneys of nursed pups of lithium medicated mothers, using analytical spectroscopy in a novel rat model. The mothers were healthy rats administered lithium via gavage (1000 mg/day Li2 CO3 per 50 kg body weight). RESULTS: Lithium was detected in the breast milk, and in the blood of pups (0.08 mM), of lithium-exposed dams at post-natal day 18 (P18), during breast-feeding. No lithium was detected after breast-feeding, at P25 (4 days after cessation of nursing). The lithium pups blood had elevated urea nitrogen at P18 and reduced total T4 at P18 and P25, indicating a longer-term effect on the kidneys and the thyroid gland. Multivariate machine-learning analysis of spectroscopy data collected from the excised kidneys of pups showed elevated potassium in lithium-exposed animals both during- and after breast-feeding. The elevated renal potassium was associated with low nephrin expression in the kidneys measured immunohistochemically during breast-feeding. After lithium exposure is stopped, the filtration of lithium from the kidneys reverses these effects. Our study showed that breastfeeding during lithium use has an effect on the kidneys of the offspring in rats.


Assuntos
Transtorno Bipolar , Leite Humano , Feminino , Ratos , Lactente , Humanos , Animais , Leite Humano/química , Lítio/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Rim , Potássio/análise , Potássio/uso terapêutico , Aleitamento Materno
5.
J Extracell Vesicles ; 11(8): e12234, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35923105

RESUMO

Breast cancer cells release a large quantity of biocargo-bearing extracellular vesicles (EVs), which mediate intercellular communication within the tumour microenvironment and promote metastasis. To identify EV-bound proteins related to metastasis, we used mass spectrometry to profile EVs from highly and poorly metastatic breast cancer lines of human and mouse origins. Comparative mass spectrometry indicated that integrins, including αv and ß1 subunits, are preferentially enriched in EVs of highly metastatic origin over those of poorly metastatic origin. These results are consistent with our histopathological findings, which show that integrin αv is associated with disease progression in breast cancer patients. Integrin αv colocalizes with the multivesicular-body marker CD63 at a higher frequency in the tumour and is enriched in circulating EVs of breast cancer patients at late stages when compared with circulating EVs from early-stage patients. With a magnetic bead-based flow cytometry assay, we confirmed that integrins αv and ß1 are enriched in the CD63+ subsets of EVs from both human and mouse highly metastatic cells. By analysing the level of integrin αv on circulating EVs, this assay could predict the metastatic potential of a xenografted mouse model. To explore the export mechanism of integrins into EVs, we performed immunoprecipitation mass spectrometry and identified members of the galectin family as potential shuttlers of integrin αvß1 into EVs. In particular, knockdown of galectin-3, but not galectin-1, causes a reduction in the levels of cell surface integrins ß1 and αv, and decreases the colocalization of these integrins with CD63. Importantly, knockdown of galectin-3 leads to a decrease of integrin αvß1 export into the EVs concomitant with a decrease in the metastatic potential of breast cancer cells. Moreover, inhibition of the integrin αvß1 complex leads to a reduction in the binding of EVs to fibronectin, suggesting that integrin αvß1 is important for EV retention in the extracellular matrix. EVs retained in the extracellular matrix are taken up by fibroblasts, which differentiate into cancer associated fibroblasts. In summary, our data indicate an important link between EV-bound integrin αvß1 with breast cancer metastasis and provide additional insights into the export of integrin αvß1 into EVs in the context of metastasis.


Assuntos
Neoplasias da Mama , Vesículas Extracelulares , Animais , Neoplasias da Mama/metabolismo , Vesículas Extracelulares/metabolismo , Feminino , Galectina 3 , Humanos , Integrina alfaV , Melanoma , Camundongos , Receptores de Vitronectina/metabolismo , Neoplasias Cutâneas , Microambiente Tumoral , Melanoma Maligno Cutâneo
6.
Sci Adv ; 8(8): eabg4485, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35213231

RESUMO

T cells defend against cancer and viral infections by rapidly scanning the surface of target cells seeking specific peptide antigens. This key process in adaptive immunity is sparked upon T cell receptor (TCR) binding of antigens within cell-cell junctions stabilized by integrin (LFA-1)/intercellular adhesion molecule-1 (ICAM-1) complexes. A long-standing question in this area is whether the forces transmitted through the LFA-1/ICAM-1 complex tune T cell signaling. Here, we use spectrally encoded DNA tension probes to reveal the first maps of LFA-1 and TCR forces generated by the T cell cytoskeleton upon antigen recognition. DNA probes that control the magnitude of LFA-1 force show that F>12 pN potentiates antigen-dependent T cell activation by enhancing T cell-substrate engagement. LFA-1/ICAM-1 mechanical events with F>12 pN also enhance the discriminatory power of the TCR when presented with near cognate antigens. Overall, our results show that T cells integrate multiple channels of mechanical information through different ligand-receptor pairs to tune function.

7.
J Biol Chem ; 298(4): 101726, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35157848

RESUMO

Heterogeneity within the glycocalyx influences cell adhesion mechanics and signaling. However, the role of specific glycosylation subtypes in influencing cell mechanics via alterations of receptor function remains unexplored. It has been shown that the addition of sialic acid to terminal glycans impacts growth, development, and cancer progression. In addition, the sialyltransferase ST6Gal-I promotes epidermal growth factor receptor (EGFR) activity, and we have shown EGFR is an 'allosteric mechano-organizer' of integrin tension. Here, we investigated the impact of ST6Gal-I on cell mechanics. Using DNA-based tension gauge tether probes of variable thresholds, we found that high ST6Gal-I activity promotes increased integrin forces and spreading in Cos-7 and OVCAR3, OVCAR5, and OV4 cancer cells. Further, employing inhibitors and function-blocking antibodies against ß1, ß3, and ß5 integrins and ST6Gal-I targets EGFR, tumor necrosis factor receptor, and Fas cell surface death receptor, we validated that the observed phenotypes are EGFR-specific. We found that while tension, contractility, and adhesion are extracellular-signal-regulated kinase pathway-dependent, spreading, proliferation, and invasion are phosphoinositide 3-kinase-Akt serine/threonine kinase dependent. Using total internal reflection fluorescence microscopy and flow cytometry, we also show that high ST6Gal-I activity leads to sustained EGFR membrane retention, making it a key regulator of cell mechanics. Our findings suggest a novel sialylation-dependent mechanism orchestrating cellular mechanics and enhancing cell motility via EGFR signaling.


Assuntos
Neoplasias Ovarianas , Sialiltransferases , Linhagem Celular Tumoral , Movimento Celular , Receptores ErbB/metabolismo , Feminino , Humanos , Integrinas/metabolismo , Neoplasias Ovarianas/enzimologia , Neoplasias Ovarianas/fisiopatologia , Fosfatidilinositol 3-Quinases/metabolismo , Sialiltransferases/metabolismo , beta-D-Galactosídeo alfa 2-6-Sialiltransferase
8.
Bioconjug Chem ; 33(2): 279-293, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35080855

RESUMO

Delivery of nucleic acids can be hindered by multiple factors including nuclease susceptibility, endosome trapping, and clearance. Multiple nanotechnology scaffolds have offered promising solutions, and among these, lipid-based systems are advantageous because of their high biocompatibility and low toxicity. However, many lipid nanoparticle systems still have issues regarding stability, rapid clearance, and cargo leakage. Herein, we demonstrate the use of a synthetic nanodisc (ND) scaffold functionalized with an anti-HIF-1-α antisense oligonucleotide (ASO) to reduce HIF-1-α mRNA transcript levels. We prepared ND conjugates by using a mixture of phosphoglycerolipids with phosphocholine and phosphothioethanol headgroups that self-assemble into a ∼13 × 5 nm discoidal structure upon addition of a 22-amino-acid ApoA1 mimetic peptide. Optimized reaction conditions yield 15 copies of the anti-HIF-1-α ASO DNA covalently conjugated to the thiolated phospholipids using maleimide-thiol chemistry. We show that DNA-ND conjugates are active, nuclease resistant, and rapidly internalized into cells to regulate HIF-1-α mRNA levels without the use of transfection agents. DNA-ND uptake is partially mediated through Scavenger Receptor B1 and the ND conjugates show enhanced knockdown of HIF-1-α compared to that of the soluble ASOs in multiple cell lines. Our results demonstrate that covalently functionalized NDs may offer an improved platform for ASO therapeutics.


Assuntos
Nanopartículas , Oligonucleotídeos Antissenso , Lipossomos , Nanopartículas/química , Oligonucleotídeos Antissenso/química , Oligonucleotídeos Antissenso/genética , RNA Mensageiro/genética
9.
Br J Cancer ; 126(1): 57-71, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34718356

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with poor prognosis. By performing multiomic profiling, we recently uncovered super-enhancer heterogeneity between breast cancer subtypes. Our data also revealed TCOF1 as a putative TNBC-specific super-enhancer-regulated gene. TCOF1 plays a critical role in craniofacial development but its function in cancer remains unclear. METHODS: Overall survival and multivariant Cox regression analyses were conducted using the METABRIC data set. The effect of TCOF1 knockout on TNBC growth and stemness was evaluated by in vitro and in vivo assays. RNA-seq and rescue experiments were performed to explore the underlying mechanisms. RESULTS: TCOF1 is frequently upregulated in TNBC and its elevated expression correlates with shorter overall survival. TCOF1 depletion significantly inhibits the growth and stemness of basal-like TNBC, but not of mesenchymal-like cells, highlighting the distinct molecular dependency in different TNBC subgroups. RNA-seq uncovers several stem cell molecules regulated by TCOF1. We further demonstrate that KIT is a downstream effector of TCOF1 in mediating TNBC stemness. TCOF1 expression in TNBC is regulated by the predicted super-enhancer. CONCLUSIONS: TCOF1 depletion potently attenuates the growth and stemness of basal-like TNBC. Expression of TCOF1 may serve as a TNBC prognostic marker and a therapeutic target.


Assuntos
Regulação Neoplásica da Expressão Gênica , Células-Tronco Neoplásicas/patologia , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Biologia Computacional/métodos , Bases de Dados Genéticas , Humanos , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Proteínas Nucleares/genética , Fosfoproteínas/genética , Prognóstico , Taxa de Sobrevida , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
10.
iScience ; 24(11): 103256, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34761180

RESUMO

Neutrophil extracellular traps (NETs) have been implicated in the pathogenesis of acute respiratory distress syndrome (ARDS) driven by viruses or bacteria, as well as in numerous immune-mediated disorders. Histone citrullination by the enzyme peptidylarginine deiminase 4 (PAD4) and the consequent decondensation of chromatin are hallmarks in the induction of NETs. Nevertheless, additional histone modifications that may govern NETosis are largely overlooked. Herein, we show that histone deacetylases (HDACs) play critical roles in driving NET formation in human and mouse neutrophils. HDACs belonging to the zinc-dependent lysine deacetylases family are necessary to deacetylate histone H3, thus allowing the activity of PAD4 and NETosis. Of note, HDAC inhibition in mice protects against microbial-induced pneumonia and septic shock, decreasing NETosis and inflammation. Collectively, our findings illustrate a new fundamental step that governs the release of NETs and points to HDAC inhibitors as therapeutic agents that may be used to protect against ARDS and sepsis.

11.
Cancer Res ; 81(22): 5692-5705, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34551961

RESUMO

The tumor microenvironment plays a critical role in maintaining the immature phenotype of tumor-initiating cells (TIC) to promote cancer. Hepatocellular carcinoma (HCC) is a unique disease in that it develops in the setting of fibrosis and cirrhosis. This pathologic state commonly shows an enrichment of stromal myofibroblasts, which constitute the bulk of the tumor microenvironment and contribute to disease progression. Follistatin-like 1 (FSTL1) has been widely reported as a proinflammatory mediator in different fibrosis-related and inflammatory diseases. Here we show FSTL1 expression to be closely correlated with activated fibroblasts and to be elevated in regenerative, fibrotic, and disease liver states in various mouse models. Consistently, FSTL1 lineage cells gave rise to myofibroblasts in a CCL4-induced hepatic fibrosis mouse model. Clinically, high FSTL1 in fibroblast activation protein-positive (FAP+) fibroblasts were significantly correlated with more advanced tumors in patients with HCC. Although FSTL1 was expressed in primary fibroblasts derived from patients with HCC, it was barely detectable in HCC cell lines. Functional investigations revealed that treatment of HCC cells and patient-derived 3D organoids with recombinant FSTL1 or with conditioned medium collected from hepatic stellate cells or from cells overexpressing FSTL1 could promote HCC growth and metastasis. FSTL1 bound to TLR4 receptor, resulting in activation of AKT/mTOR/4EBP1 signaling. In a preclinical mouse model, blockade of FSTL1 mitigated HCC malignancy and metastasis, sensitized HCC tumors to sorafenib, prolonged survival, and eradicated the TIC subset. Collectively, these data suggest that FSTL1 may serve as an important novel diagnostic/prognostic biomarker and therapeutic target in HCC. SIGNIFICANCE: This study shows that FSTL1 secreted by activated fibroblasts in the liver microenvironment augments hepatocellular carcinoma malignancy, providing a potential new strategy to improve treatment of this aggressive disease.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/secundário , Fibroblastos/patologia , Proteínas Relacionadas à Folistatina/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/patologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células , Fibroblastos/metabolismo , Proteínas Relacionadas à Folistatina/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Angew Chem Int Ed Engl ; 60(33): 18044-18050, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-33979471

RESUMO

Mechanotransduction, the interplay between physical and chemical signaling, plays vital roles in many biological processes. The state-of-the-art techniques to quantify cell forces employ deformable polymer films or molecular probes tethered to glass substrates. However, the applications of these assays in fundamental and clinical research are restricted by the planar geometry and low throughput of microscopy readout. Herein, we develop a DNA-based microparticle tension sensor, which features a spherical surface and thus allows for investigation of mechanotransduction at curved interfaces. The micron-scale of µTS enables flow cytometry readout, which is rapid and high throughput. We applied the method to map and measure T-cell receptor forces and platelet integrin forces at 12 and 56 pN thresholds. Furthermore, we quantified the inhibition efficiency of two anti-platelet drugs providing a proof-of-concept demonstration of µTS to screen drugs that modulate cellular mechanics.


Assuntos
DNA/metabolismo , Ensaios de Triagem em Larga Escala , Actomiosina/farmacologia , Amidas/farmacologia , DNA/química , Relação Dose-Resposta a Droga , Humanos , Mecanotransdução Celular/efeitos dos fármacos , Imagem Óptica , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Piridinas/farmacologia
13.
Nat Commun ; 12(1): 2242, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33854062

RESUMO

Breast cancer is a heterogeneous disease, affecting over 3.5 million women worldwide, yet the functional role of cis-regulatory elements including super-enhancers in different breast cancer subtypes remains poorly characterized. Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with a poor prognosis. Here we apply integrated epigenomic and transcriptomic profiling to uncover super-enhancer heterogeneity between breast cancer subtypes, and provide clinically relevant biological insights towards TNBC. Using CRISPR/Cas9-mediated gene editing, we identify genes that are specifically regulated by TNBC-specific super-enhancers, including FOXC1 and MET, thereby unveiling a mechanism for specific overexpression of the key oncogenes in TNBC. We also identify ANLN as a TNBC-specific gene regulated by super-enhancer. Our studies reveal a TNBC-specific epigenomic landscape, contributing to the dysregulated oncogene expression in breast tumorigenesis.


Assuntos
Neoplasias de Mama Triplo Negativas/genética , Animais , Linhagem Celular Tumoral , Elementos Facilitadores Genéticos , Feminino , Fatores de Transcrição Forkhead/genética , Edição de Genes , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Nus , Proteínas dos Microfilamentos/genética , Proteínas Proto-Oncogênicas c-met/genética
14.
J Extracell Vesicles ; 10(4): e12057, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33643546

RESUMO

Natural extracellular vesicles (EVs) are ideal drug carriers due to their remarkable biocompatibility. Their delivery specificity can be achieved by the conjugation of targeting ligands. However, existing methods to engineer target-specific EVs are tedious or inefficient, having to compromise between harsh chemical treatments and transient interactions. Here, we describe a novel method for the covalent conjugation of EVs with high copy numbers of targeting moieties using protein ligases. Conjugation of EVs with either an epidermal growth factor receptor (EGFR)-targeting peptide or anti-EGFR nanobody facilitates their accumulation in EGFR-positive cancer cells, both in vitro and in vivo. Systemic delivery of paclitaxel by EGFR-targeting EVs at a low dose significantly increases drug efficacy in a xenografted mouse model of EGFR-positive lung cancer. The method is also applicable to the conjugation of EVs with peptides and nanobodies targeting other receptors, such as HER2 and SIRP alpha, and the conjugated EVs can deliver RNA in addition to small molecules, supporting the versatile application of EVs in cancer therapies. This simple, yet efficient and versatile method for the stable surface modification of EVs bypasses the need for genetic and chemical modifications, thus facilitating safe and specific delivery of therapeutic payloads to target cells.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Vesículas Extracelulares , Peptídeos/uso terapêutico , Anticorpos de Domínio Único/uso terapêutico , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Receptores ErbB/química , Receptores ErbB/uso terapêutico , Eritrócitos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Paclitaxel/uso terapêutico , Peptídeos/química , Anticorpos de Domínio Único/química , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Bipolar Disord ; 23(6): 615-625, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33507599

RESUMO

BACKGROUND: Lithium is especially taken as a maintenance medication for Bipolar Disorder. In women with bipolar disorder, lithium is often effective during postpartum period, but breast-feeding for medicated mothers is controversial because of harmful effects for her child. At present, the biological mechanisms of lithium are not well-understood, affecting its usage and overall health implications. PROCEDURE: We developed a rat lithium and breast-feeding model at human therapeutic levels to study the effects of lithium exposure through breast-milk on pups' thyroid function. Novel laser analytical spectroscopy, along with traditional blood and immunohistochemical tests, were applied to further investigate the mechanisms behind the thyroid dysfunction. Maternal iodine supplementation was evaluated as a therapeutic method to address the pups' thyroid dysfunction. RESULTS: Pups exposed to lithium via breastmilk, even with the dam on a sub-therapeutic level, experienced weight gain, reduced blood thyroxine (T4 ), and elevated blood urea nitrogen, indicating effects on thyroid and kidney function. We show that lithium inhibited iodine uptake by thyroid follicles, initiating a mechanism that reduced iodination of tyrosine, thyroglobulin cleavage, and thyroid hormone production. Importantly, infant thyroid function can be significantly improved by administering supplementary iodine to the medicated dam's diet during breast-feeding. CONCLUSION: These results elucidate the mechanisms of lithium in thyroid function, provide valuable information on use postpartum, and suggest a clinically applicable remedy to side-effects. The results are particularly important for patients (and their infants) who respond well to lithium and need, or choose, to breast-feed.


Assuntos
Transtorno Bipolar , Iodo , Animais , Suplementos Nutricionais , Feminino , Humanos , Iodo/análise , Lítio , Leite Humano , Ratos , Glândula Tireoide/diagnóstico por imagem , Tireotropina
17.
Neuropathol Appl Neurobiol ; 47(3): 441-453, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33107057

RESUMO

AIMS: A variety of tissue clearing techniques have been developed to render intact tissue transparent. For thicker samples, additional partial tissue delipidation is required before immersion into the final refractive index (RI)-matching solution, which alone is often inadequate to achieve full tissue transparency. However, it is difficult to determine a sufficient degree of tissue delipidation, excess of which can result in tissue distortion and protein loss. Here, we aim to develop a clearing strategy that allows better monitoring and more precise determination of delipidation progress. METHODS: We combined the detergent sodium dodecyl sulphate (SDS) with OPTIClear, a RI-matching solution, to form a strategy termed Accurate delipidation with Optimal Clearing (Accu-OptiClearing). Accu-OptiClearing allows for a better preview of the final tissue transparency achieved when immersed in OPTIClear alone just before imaging. We assessed for the changes in clearing rate, protein loss, degree of tissue distortion, and preservation of antigens. RESULTS: Partial delipidation using Accu-OptiClearing accelerated tissue clearing and better preserved tissue structure and antigens than delipidation with SDS alone. Despite achieving similar transparency in the final OPTIClear solution, more lipids were retained in samples cleared with Accu-OptiClearing compared to SDS. CONCLUSIONS: Combining the RI-matching solution OPTIClear with detergents, Accu-OptiClearing, can avoid excessive delipidation, leading to accelerated tissue clearing, less tissue damage and better preserved antigens.


Assuntos
Encéfalo , Técnicas de Preparação Histocitológica/métodos , Imageamento Tridimensional/métodos , Animais , Artefatos , Feminino , Masculino , Camundongos , Microscopia Confocal/métodos , Ratos , Ratos Sprague-Dawley , Dodecilsulfato de Sódio , Tensoativos , Peixe-Zebra
18.
PLoS One ; 15(12): e0244542, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33378409

RESUMO

Tea is a popular beverage consumed at different temperatures. The effect of tea on teeth at different temperatures has not been studied previously. The present study used an in vitro green tea immersed tooth model at different tea temperatures (hot and cold) compared to an in vivo tea administration model allowing rats to drink tea over the course of a week. The elements present in tea leaves were identified by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and compared to the elements in teeth (enamel surface) using Laser-Induced Breakdown Spectroscopy (LIBS). Here, LIBS demonstrated in vivo and in vitro green tea treatments resulted in a significant increase in the mineral elements found in enamel. For the in vitro assessment, elements in enamel varied based on cold-tea and hot-tea treatment; however, hot water reduced the elements in enamel. Atomic force microscopy found the in vivo tea group had a higher roughness average (RA) compared with the in vivo water group. Cold tea and hot tea in vitro groups demonstrated lower RA than in vitro water controls. Scanning electron microscopy found hot water induced cracks more than 1.3µm in enamel while cold tea and hot tea promoted the adhering of extrinsic matter to teeth. Overall, teeth treated to high temperature lost the mineral phase leading to demineralization. Our results indicate that green tea protects enamel, but its protective action in dental structures is enhanced at cold temperature.


Assuntos
Camellia sinensis/química , Extratos Vegetais/administração & dosagem , Chá/química , Dente/ultraestrutura , Animais , Temperatura Baixa , Temperatura Alta , Masculino , Espectrometria de Massas , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Modelos Animais , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos , Propriedades de Superfície , Dente/efeitos dos fármacos
19.
Adv Sci (Weinh) ; 7(21): 2002157, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33173740

RESUMO

In hepatocellular carcinoma (HCC) patients with extrahepatic metastasis, the lung is the most frequent site of metastasis. However, how the lung microenvironment favors disseminated cells remains unclear. Here, it is found that nidogen 1 (NID1) in metastatic HCC cell-derived extracellular vesicles (EVs) promotes pre-metastatic niche formation in the lung by enhancing angiogenesis and pulmonary endothelial permeability to facilitate colonization of tumor cells and extrahepatic metastasis. EV-NID1 also activates fibroblasts, which secrete tumor necrosis factor receptor 1 (TNFR1), facilitate lung colonization of tumor cells, and augment HCC cell growth and motility. Administration of anti-TNFR1 antibody effectively diminishes lung metastasis induced by the metastatic HCC cell-derived EVs in mice. In the clinical perspective, analysis of serum EV-NID1 and TNFR1 in HCC patients reveals their positive correlation and association with tumor stages suggesting the potential of these molecules as noninvasive biomarkers for the early detection of HCC. In conclusion, these results demonstrate the interplay of HCC EVs and activated fibroblasts in pre-metastatic niche formation and how blockage of their functions inhibits distant metastasis to the lungs. This study offers promise for the new direction of HCC treatment by targeting oncogenic EV components and their mediated pathways.

20.
Expert Rev Mol Diagn ; 20(11): 1149-1159, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33040630

RESUMO

BACKGROUND: Although the majority of nasopharyngeal carcinoma (NPC) patients demonstrate favorable outcomes after radiotherapy and/or chemotherapy, about 8-10% of patients will develop recurrent disease, and genomic alterations (GAs) associated with the recurrence are unclear. METHODS: This study investigated the GAs in the paired primary tumors and recurrent tumors of 7 NPC patients with relapse, as well as the primary tumors of 15 NPC patients without relapse by deep targeted next-generation sequencing on 440 cancer-related genes. RESULTS: BRCA1 and TP53 mutations were significantly enriched in patients with relapse (P = 0.021 and P = 0.023, respectively). Survival analysis revealed that the GAs of TP53, ZNF217, VEGFB, CDKN1B, GNAS, PRDM1, and MEN1 were associated with significantly shorter overall survival. The GAs of the tumor also altered after treatment in the relapsed group, and five genes (CDK4, FGFR3, ALK, BRCA1, and CHEK2) in the recurrent tumors were potentially druggable. CONCLUSIONS: The discovery of GAs associated with recurrence or survival in NPC may serve as potential prognostic gene signatures of high-risk patients. Targeted therapies are available in some of the clinically relevant GAs and may be considered in future clinical trials. Given the limitation of the sample size, validation by a larger cohort is warranted.


Assuntos
Biomarcadores Tumorais , Variação Genética , Genômica , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/genética , Gerenciamento Clínico , Suscetibilidade a Doenças , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/terapia , Prognóstico , Recidiva
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