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1.
Mol Cell ; 67(2): 308-321.e6, 2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28732206

RESUMO

Enhancer activation is a critical step for gene activation. Here we report an epigenetic crosstalk at enhancers between the UTX (H3K27 demethylase)-MLL4 (H3K4 methyltransferase) complex and the histone acetyltransferase p300. We demonstrate that UTX, in a demethylase activity-independent manner, facilitates conversion of inactive enhancers in embryonic stem cells to an active (H3K4me1+/H3K27ac+) state by recruiting and coupling the enzymatic functions of MLL4 and p300. Loss of UTX leads to attenuated enhancer activity, characterized by reduced levels of H3K4me1 and H3K27ac as well as impaired transcription. The UTX-MLL4 complex enhances p300-dependent H3K27 acetylation through UTX-dependent stimulation of p300 recruitment, while MLL4-mediated H3K4 monomethylation, reciprocally, requires p300 function. Importantly, MLL4-generated H3K4me1 further enhances p300-dependent transcription. This work reveals a previously unrecognized cooperativity among enhancer-associated chromatin modulators, including a unique function for UTX, in establishing an "active enhancer landscape" and defines a detailed mechanism for the joint deposition of H3K4me1 and H3K27ac.


Assuntos
Cromatina/metabolismo , Proteína p300 Associada a E1A/metabolismo , Células-Tronco Embrionárias/enzimologia , Elementos Facilitadores Genéticos , Histona Desmetilases/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Transcrição Gênica , Ativação Transcricional , Animais , Cromatina/genética , Montagem e Desmontagem da Cromatina , Proteína p300 Associada a E1A/genética , Retroalimentação Fisiológica , Redes Reguladoras de Genes , Células HEK293 , Histona Desmetilases/genética , Histona-Lisina N-Metiltransferase/genética , Histonas/metabolismo , Humanos , Masculino , Metilação , Camundongos , Interferência de RNA , Transfecção
2.
J Cell Mol Med ; 28(4): e18139, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38334198

RESUMO

Platelets assume a pivotal role in the cardiovascular diseases (CVDs). Thus, targeting platelet activation is imperative for mitigating CVDs. Ginkgetin (GK), from Ginkgo biloba L, renowned for its anticancer and neuroprotective properties, remains unexplored concerning its impact on platelet activation, particularly in humans. In this investigation, we delved into the intricate mechanisms through which GK influences human platelets. At low concentrations (0.5-1 µM), GK exhibited robust inhibition of collagen and arachidonic acid (AA)-induced platelet aggregation. Intriguingly, thrombin and U46619 remained impervious to GK's influence. GK's modulatory effect extended to ATP release, P-selectin expression, intracellular calcium ([Ca2+ ]i) levels and thromboxane A2 formation. It significantly curtailed the activation of various signaling cascades, encompassing phospholipase Cγ2 (PLCγ2)/protein kinase C (PKC), phosphoinositide 3-kinase/Akt/glycogen synthase kinase-3ß and mitogen-activated protein kinases. GK's antiplatelet effect was not reversed by SQ22536 (an adenylate cyclase inhibitor) or ODQ (a guanylate cyclase inhibitor), and GK had no effect on the phosphorylation of vasodilator-stimulated phosphoproteinSer157 or Ser239 . Moreover, neither cyclic AMP nor cyclic GMP levels were significantly increased after GK treatment. In mouse studies, GK notably extended occlusion time in mesenteric vessels, while sparing bleeding time. In conclusion, GK's profound impact on platelet activation, achieved through inhibiting PLCγ2-PKC cascade, culminates in the suppression of downstream signaling and, ultimately, the inhibition of platelet aggregation. These findings underscore the promising therapeutic potential of GK in the CVDs.


Assuntos
Biflavonoides , Nucleotídeos Cíclicos , Fosfolipases , Humanos , Animais , Camundongos , Nucleotídeos Cíclicos/metabolismo , Nucleotídeos Cíclicos/farmacologia , Fosfolipase C gama/metabolismo , Ácido Araquidônico/farmacologia , Ácido Araquidônico/metabolismo , Fosfolipases/metabolismo , Fosfolipases/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , Ativação Plaquetária , Plaquetas/metabolismo , Agregação Plaquetária , Proteína Quinase C/metabolismo , Fosforilação , Colágeno/metabolismo
3.
Eye Contact Lens ; 50(2): 84-90, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38193846

RESUMO

OBJECTIVES: To determine the location and intensity of the corneal pigmented arc in orthokeratology (ortho-k)-treated children and its relationship with annual axial length (AL) change using Pentacam. METHODS: This retrospective cohort study enrolled children aged 9 to 15 years who had been followed up for at least one year after ortho-k treatment for myopia control. A Pentacam was used to determine the location and intensity of pigmented arc after lens wear. Annual AL changes were further used as the outcome measurement to determine their relationships with the location and intensity of pigmented arc using generalized estimating equations (GEE). RESULTS: In total, 62 eyes from 33 patients (mean age 10.9 years) were included in our final analysis. The mean follow-up time was 30.6 months. The mean annual AL changes were 0.10 mm. Age statistically correlated with annual AL change (GEE, P= 0.033). In addition, the annual AL change was negatively associated with the relative vertical distance of the lowest density of pigmented arc point based on the visual center, pupil center, and corneal thinnest point after adjustment with age ( P =0.005, P =0.004, and P< 0.001, respectively). CONCLUSIONS: Pentacam could be a useful tool for evaluating the location and intensity of the corneal pigmented arc. In addition, there was a negative correlation between the vertical distance of the pigmented arc and annual AL change. These findings may provide important information regarding myopia control, next-generation ortho-k design, and prescription.


Assuntos
Lentes de Contato , Miopia , Procedimentos Ortoceratológicos , Transtornos da Pigmentação , Criança , Humanos , Estudos Retrospectivos , Córnea , Miopia/terapia , Topografia da Córnea , Refração Ocular , Transtornos da Visão , Comprimento Axial do Olho
4.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396774

RESUMO

Platelets assume a pivotal role in the pathogenesis of cardiovascular diseases (CVDs), emphasizing their significance in disease progression. Consequently, addressing CVDs necessitates a targeted approach focused on mitigating platelet activation. Eugenol, predominantly derived from clove oil, is recognized for its antibacterial, anticancer, and anti-inflammatory properties, rendering it a valuable medicinal agent. This investigation delves into the intricate mechanisms through which eugenol influences human platelets. At a low concentration of 2 µM, eugenol demonstrates inhibition of collagen and arachidonic acid (AA)-induced platelet aggregation. Notably, thrombin and U46619 remain unaffected by eugenol. Its modulatory effects extend to ATP release, P-selectin expression, and intracellular calcium levels ([Ca2+]i). Eugenol significantly inhibits various signaling cascades, including phospholipase Cγ2 (PLCγ2)/protein kinase C (PKC), phosphoinositide 3-kinase/Akt/glycogen synthase kinase-3ß, mitogen-activated protein kinases, and cytosolic phospholipase A2 (cPLA2)/thromboxane A2 (TxA2) formation induced by collagen. Eugenol selectively inhibited cPLA2/TxA2 phosphorylation induced by AA, not affecting p38 MAPK. In ADP-treated mice, eugenol reduced occluded lung vessels by platelet thrombi without extending bleeding time. In conclusion, eugenol exerts a potent inhibitory effect on platelet activation, achieved through the inhibition of the PLCγ2-PKC and cPLA2-TxA2 cascade, consequently suppressing platelet aggregation. These findings underscore the potential therapeutic applications of eugenol in CVDs.


Assuntos
Eugenol , Embolia Pulmonar , Humanos , Camundongos , Animais , Eugenol/farmacologia , Eugenol/uso terapêutico , Eugenol/metabolismo , Fosfolipase C gama/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Modelos Animais de Doenças , Ativação Plaquetária , Agregação Plaquetária , Plaquetas/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Tromboxano A2/metabolismo , Colágeno/metabolismo , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/metabolismo , Fosfolipases A2 Citosólicas/metabolismo
5.
Biomed Eng Online ; 22(1): 54, 2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37237394

RESUMO

OBJECTIVES: Use of an AI system based on deep learning to investigate whether the system can aid in distinguishing malignant from benign calcifications on spot magnification mammograms, thus potentially reducing unnecessary biopsies. METHODS: In this retrospective study, we included public and in-house datasets with annotations for the calcifications on both craniocaudal and mediolateral oblique vies, or both craniocaudal and mediolateral views of each case of mammograms. All the lesions had pathological results for correlation. Our system comprised an algorithm based on You Only Look Once (YOLO) named adaptive multiscale decision fusion module. The algorithm was pre-trained on a public dataset, Curated Breast Imaging Subset of Digital Database for Screening Mammography (CBIS-DDSM), then re-trained and tested on the in-house dataset of spot magnification mammograms. The performance of the system was investigated by receiver operating characteristic (ROC) analysis. RESULTS: We included 1872 images from 753 calcification cases (414 benign and 339 malignant) from CBIS-DDSM. From the in-house dataset, 636 cases (432 benign and 204 malignant) with 1269 spot magnification mammograms were included, with all lesions being recommended for biopsy by radiologists. The area under the ROC curve for our system on the in-house testing dataset was 0.888 (95% CI 0.868-0.908), with a sensitivity of 88.4% (95% CI 86.9-8.99%), specificity of 80.8% (95% CI 77.6-84%), and an accuracy of 84.6% (95% CI 81.8-87.4%) at the optimal cutoff value. Using the system with two views of spot magnification mammograms, 80.8% benign biopsies could be avoided. CONCLUSION: The AI system showed good accuracy for classification of calcifications on spot magnification mammograms which were all categorized as suspicious by radiologists, thereby potentially reducing unnecessary biopsies.


Assuntos
Neoplasias da Mama , Calcinose , Humanos , Feminino , Mamografia/métodos , Estudos Retrospectivos , Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer , Calcinose/diagnóstico por imagem , Inteligência Artificial
6.
Int J Mol Sci ; 24(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38139016

RESUMO

Müller cells play a critical role in the closure of macular holes, and their proliferation and migration are facilitated by the internal limiting membrane (ILM). Despite the importance of this process, the underlying molecular mechanism remains underexplored. This study investigated the effects of ILM components on the microRNA (miRNA) profile of Müller cells. Rat Müller cells (rMC-1) were cultured with a culture insert and varying concentrations of ILM component coatings, namely, collagen IV, laminin, and fibronectin, and cell migration was assessed by measuring cell-free areas in successive photographs following insert removal. MiRNAs were then extracted from these cells and analyzed. Mimics and inhibitors of miRNA candidates were transfected into Müller cells, and a cell migration assay and additional cell viability assays were performed. The results revealed that the ILM components promoted Müller cell migration (p < 0.01). Among the miRNA candidates, miR-194-3p was upregulated, whereas miR-125b-1-3p, miR-132-3p, miR-146b-5p, miR-152-3p, miR-196a-5p, miR-542-5p, miR-871-3p, miR-1839-5p, and miR-3573-3p were significantly downregulated (p < 0.05; fold change > 1.5). Moreover, miR-152-3p and miR-196a-5p reduced cell migration (p < 0.05) and proliferation (p < 0.001), and their suppressive effects were reversed by their respective inhibitors. In conclusion, miRNAs were regulated in ILM component-activated Müller cells, with miR-152-3p and miR-196a-5p regulating Müller cell migration and proliferation. These results serve as a basis for understanding the molecular healing process of macular holes and identifying potential new target genes in future research.


Assuntos
MicroRNAs , Perfurações Retinianas , Animais , Ratos , Colágeno Tipo IV/farmacologia , Células Ependimogliais , Membranas , MicroRNAs/genética , MicroRNAs/farmacologia , Perfurações Retinianas/genética
7.
Graefes Arch Clin Exp Ophthalmol ; 260(4): 1265-1273, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34694457

RESUMO

PURPOSE: To evaluate the 2-year efficacy and safety of micropulse transscleral cyclophotocoagulation (MP-TSCPC) in Taiwanese patients with glaucoma. METHODS: We included the patients who received standardized MP-TSCPC with follow-up examinations on a regular basis for 24 months. Treatment success was defined as the attainment of a postoperative intraocular pressure (IOP) between 6 and 21 mmHg or a ≥ 20% reduction in IOP from baseline without an increase in glaucoma medications. RESULTS: A total of 60 eyes from 56 patients who underwent MP-TSCPC for refractory glaucoma were included. The median age at MP-TSCPC intervention was 58.9 ± 12.4 years. The percentage of treatment success was 88.3% at 3 months, 83.3% at 6 months, 78.3% at 12 months, and 75.0% at 24 months. The mean baseline IOP prior to MP-TSCPC was 34 ± 11.9 mmHg (range 14-56 mmHg). The mean postoperative IOP decreased to 20.9 ± 10.0 mmHg, 18.0 ± 7.8 mmHg, 17.5 ± 6.4 mmHg, and 18.2 ± 7.1 mmHg after 3 months, 6 months, 12 months, and 24 months, respectively, in successful cases. The mean number of glaucoma medications at baseline was 3.8 ± 0.2, and the mean numbers of glaucoma medications at postoperative months 3, 6, 12, and 24 were 2.6 ± 0.7, 2.8 ± 0.6, 2.5 ± 1.4 and 2.6 ± 1.4, respectively, in successful cases. Younger age and prior CW-TSCPC significantly contributed to surgical failure in the multivariate model. Complications after MP-TSCPC included mild anterior chamber inflammation, conjunctival hemorrhage, hypotony, and mydriasis, and all subsided after treatment. None of the eyes developed vitreous hemorrhage, cystoid macular edema, or phthisis bulbi in the late postoperative period. CONCLUSIONS: This study demonstrated that younger age and prior CW-TSCPC were risk factors for MP-TSCPC failure within 2 years. MP-TSCPC might be safe and effective for refractory glaucoma patients with maximal antiglaucoma medications.


Assuntos
Fotocoagulação a Laser , Lasers Semicondutores , Corpo Ciliar/cirurgia , Humanos , Pressão Intraocular , Lasers Semicondutores/uso terapêutico , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Acuidade Visual
8.
Biochem Soc Trans ; 49(3): 1041-1054, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34156443

RESUMO

Enhancers are cis-regulatory elements that play essential roles in tissue-specific gene expression during development. Enhancer function in the expression of developmental genes requires precise regulation, while deregulation of enhancer function could be the main cause of tissue-specific cancer development. MLL3/KMT2C and MLL4/KMT2D are two paralogous histone modifiers that belong to the SET1/MLL (also named COMPASS) family of lysine methyltransferases and play critical roles in enhancer-regulated gene activation. Importantly, large-scale DNA sequencing studies have revealed that they are amongst the most frequently mutated genes associated with human cancers. MLL3 and MLL4 form identical multi-protein complexes for modifying mono-methylation of histone H3 lysine 4 (H3K4) at enhancers, which together with the p300/CBP-mediated H3K27 acetylation can generate an active enhancer landscape for long-range target gene activation. Recent studies have provided a better understanding of the possible mechanisms underlying the roles of MLL3/MLL4 complexes in enhancer regulation. Moreover, accumulating studies offer new insights into our knowledge of the potential role of MLL3/MLL4 in cancer development. In this review, we summarize recent evidence on the molecular mechanisms of MLL3/MLL4 in the regulation of active enhancer landscape and long-range gene expression, and discuss their clinical implications in human cancers.


Assuntos
Proteínas de Ligação a DNA/genética , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Histonas/metabolismo , Metiltransferases/genética , Complexos Multiproteicos/genética , Animais , Proteínas de Ligação a DNA/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Metiltransferases/metabolismo , Complexos Multiproteicos/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia
9.
Exp Eye Res ; 202: 108352, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33166502

RESUMO

This study investigated the effects of growth factors and internal limiting membrane components on Müller cell migration. We studied the effects of epidermal growth factor (EGF), fibroblast growth factor (FGF), somatomedin (IGF-1), platelet derived growth factor (PDGF), and stromal cell-derived factor-1 alpha (SDF-1α) as well as collagen IV, laminin, and fibronectin on the proliferative and migratory activities of rat Müller cells in vitro. A water soluble tetrazolium-1 assay was used to quantify the viability of Müller cells in respective cultures, and analysis was performed using an enzyme-linked immunosorbent assay reader. All the factors examined had significant proliferative effects on cultured Müller cells (p < .05). A two-well Ibidi silicone culture insert was used to assess Müller cell migration. Müller cells cultured in EGF, FGF, IGF-1, collagen IV, and laminin but not in SDF, PDGF, or fibronectin effectively increased the cell migratory activity (p < .001). In addition, combined EGF and collagen IV, combined FGF and collagen IV, and combined IGF-1 and laminin exhibited more significant (p < .001) effects on Müller cell migration compared with culture a single factor. In summary, this study revealed the combinatorial effects of various growth factors and individual internal limiting membrane constituents. This may assist Müller cell migration together with the macular hole healing process.


Assuntos
Células Ependimogliais/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Perfurações Retinianas/metabolismo , Linhagem Celular , Movimento Celular , Células Ependimogliais/patologia , Humanos , Perfurações Retinianas/patologia
10.
J Biomed Sci ; 28(1): 85, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34886870

RESUMO

Parkinson's disease (PD), or paralysis agitans, is a common neurodegenerative disease characterized by dopaminergic deprivation in the basal ganglia because of neuronal loss in the substantia nigra pars compacta. Clinically, PD apparently involves both hypokinetic (e.g. akinetic rigidity) and hyperkinetic (e.g. tremor/propulsion) symptoms. The symptomatic pathogenesis, however, has remained elusive. The recent success of deep brain stimulation (DBS) therapy applied to the subthalamic nucleus (STN) or the globus pallidus pars internus indicates that there are essential electrophysiological abnormalities in PD. Consistently, dopamine-deprived STN shows excessive burst discharges. This proves to be a central pathophysiological element causally linked to the locomotor deficits in PD, as maneuvers (such as DBS of different polarities) decreasing and increasing STN burst discharges would decrease and increase the locomotor deficits, respectively. STN bursts are not so autonomous but show a "relay" feature, requiring glutamatergic synaptic inputs from the motor cortex (MC) to develop. In PD, there is an increase in overall MC activities and the corticosubthalamic input is enhanced and contributory to excessive burst discharges in STN. The increase in MC activities may be relevant to the enhanced beta power in local field potentials (LFP) as well as the deranged motor programming at the cortical level in PD. Moreover, MC could not only drive erroneous STN bursts, but also be driven by STN discharges at specific LFP frequencies (~ 4 to 6 Hz) to produce coherent tremulous muscle contractions. In essence, PD may be viewed as a disorder with deranged rhythms in the cortico-subcortical re-entrant loops, manifestly including STN, the major component of the oscillating core, and MC, the origin of the final common descending motor pathways. The configurations of the deranged rhythms may play a determinant role in the symptomatic pathogenesis of PD, and provide insight into the mechanism underlying normal motor control. Therapeutic brain stimulation for PD and relevant disorders should be adaptively exercised with in-depth pathophysiological considerations for each individual patient, and aim at a final normalization of cortical discharge patterns for the best ameliorating effect on the locomotor and even non-motor symptoms.


Assuntos
Córtex Motor/fisiopatologia , Neurônios/fisiologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiopatologia , Fenômenos Eletrofisiológicos , Humanos
11.
Int J Mol Sci ; 22(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34681769

RESUMO

The role of activated platelets in acute and chronic cardiovascular diseases (CVDs) is well established. Therefore, antiplatelet drugs significantly reduce the risk of severe CVDs. Evodia rutaecarpa (Wu-Chu-Yu) is a well-known Chinese medicine, and rutaecarpine (Rut) is a main bioactive component with substantial beneficial properties including vasodilation. To address a research gap, we investigated the inhibitory mechanisms of Rut in washed human platelets and experimental mice. At low concentrations (1-5 µM), Rut strongly inhibited collagen-induced platelet aggregation, whereas it exerted only a slight or no effect on platelets stimulated with other agonists (e.g., thrombin). Rut markedly inhibited P-selectin expression; adenosine triphosphate release; [Ca2+]i mobilization; hydroxyl radical formation; and phospholipase C (PLC)γ2/protein kinase C (PKC), mitogen-activated protein kinase, and phosphoinositide 3-kinase (PI3K)/Akt/glycogen synthase kinase-3ß (GSK3ß) phosphorylation stimulated by collagen. SQ22536 (an adenylate cyclase inhibitor) or ODQ (a guanylate cyclase inhibitor) did not reverse Rut-mediated antiplatelet aggregation. Rut was not directly responding to vasodilator-stimulated phosphoprotein phosphorylation. Rut significantly increased the occlusion time of fluorescence irradiated thrombotic platelet plug formation. The findings demonstrated that Rut exerts a strong effect against platelet activation through the PLCγ2/PKC and PI3K/Akt/GSK3ß pathways. Thus, Rut can be a potential therapeutic agent for thromboembolic disorders.


Assuntos
Alcaloides Indólicos/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Quinazolinas/farmacologia , Trombose/prevenção & controle , Alcaloides/química , Alcaloides/farmacologia , Animais , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Evodia/química , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Alcaloides Indólicos/isolamento & purificação , Alcaloides Indólicos/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas dos Microfilamentos/metabolismo , Nucleotídeos Cíclicos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinazolinas/isolamento & purificação , Quinazolinas/uso terapêutico , Quinolinas/química , Quinolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Trombose/metabolismo , Trombose/patologia
12.
Biochem Biophys Res Commun ; 522(4): 1009-1014, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31813546

RESUMO

Hypoxia-inducible factor-1α (HIF-1α) induces cancer metastasis. We previously demonstrated that HIF-1α-induced membrane-type 4 matrix metalloproteinase (MT4-MMP) is involved in hypoxia-mediated metastasis in head and neck squamous cell carcinoma (HNSCC). However, the functions and detailed mechanisms of MT4-MMP in cancer metastasis are not well understood. In this study, we investigated whether MT4-MMP regulates invadopodia formation or individual cell movement-both critical to cancer migration and invasion-in three-dimensional (3D) environments. By expressing MT4-MMP in the HNSCC cell line FaDu, we demonstrated that MT4-MMP increases invadopodia formation and gelatin degradation. Furthermore, the amoeboid-like cell movement on collagen gel was increased by MT4-MMP expression in FaDu cells. Mechanistically, MT4-MMP may induce invadopodia formation by binding with Tks5 and PDGFRα to result in Src activation and promote amoeboid-like movement by stimulating the small GTPases Rho and Cdc42. Altogether, our data indicate that MT4-MMP induces two crucial mechanisms of cancer dissemination, invadopodia formation and amoeboid movement, and elucidate the prometastatic role of MT4-MMP in hypoxia-mediated cancer metastasis.


Assuntos
Movimento Celular , Neoplasias de Cabeça e Pescoço/enzimologia , Neoplasias de Cabeça e Pescoço/patologia , Metaloproteinases da Matriz Associadas à Membrana/metabolismo , Podossomos/patologia , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Miosinas Cardíacas/metabolismo , Linhagem Celular Tumoral , Gelatina/metabolismo , Células HEK293 , Humanos , Cadeias Leves de Miosina/metabolismo , Invasividade Neoplásica , Fosforilação , Fosfotirosina/metabolismo , Ligação Proteica , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Quinases da Família src/metabolismo
13.
Int J Cancer ; 145(8): 2209-2224, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30980673

RESUMO

The dynamic cell-cell communication is essential for tissue homeostasis in normal physiological circumstances and contributes to a diversified tumor microenvironment. Although exosomes are extracellular vesicles that actively participate in cell-cell interaction by shutting cellular components, impacts of tumor exosomes in the context of cancer stemness remain elusive. Here, we expand colorectal cancer stem cells (CRCSCs) as cancer spheroids and demonstrate that the ß-catenin/Tcf-4-activated RAB27B expression is required for the secretion of CRCSC exosomes. In an exosomal RNA sequencing analysis, a switch of exosomal RNA species from retrotransposons to microRNAs (miRNAs) is identified upon expanding CRCSCs. miRNA-146a-5p (miR-146a) is the major miRNA in CRCSC exosomes and exosomal miR-146a promotes stem-like properties and tumorigenicity by targeting Numb in recipient CRC cells. Among 53 CRC patients, those with abundant exosomal miR-146a expression in serum exhibits higher miR-146aHigh /NumbLow CRCSC traits, an increased number of tumor-filtrating CD66(+) neutrophils and a decreased number of tumor-infiltrating CD8(+) T cells. Our study elucidates a unique mechanism of tumor exosome-mediated stemness expansion.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Exossomos/genética , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Proteínas rab de Ligação ao GTP/genética , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Exossomos/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células HT29 , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Interferência de RNA , Microambiente Tumoral/genética , Proteínas rab de Ligação ao GTP/metabolismo
14.
Retina ; 39(10): 1906-1916, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30028408

RESUMO

PURPOSE: To evaluate the association between deep-superficial flow ratio (DSFR) and the treatment response of macular edema in branch retinal vein occlusion. METHODS: Thirty eyes from 30 patients with branch retinal vein occlusion who had received optical coherence tomography angiography examination were included. Seventeen normal fellow eyes acted as the control group. Patients were classified into the "good response group" and the "refractory group" by absence or presence of macular edema after 6 months of treatment. The DSFRs were calculated by dividing deep capillary plexus vessel density by superficial capillary plexus vessel density on optical coherence tomography angiography. RESULTS: The DSFR was 1.00 (SD ± 0.05) over parafoveal area in the control group. Among branch retinal vein occlusion eyes, parafoveal DSFR remained stable in the good response group (P = 0.822) and significantly decreased in the refractory group (P = 0.002). The DSFRs in the most severe nonperfusion area were significantly lower in the refractory group than in the good response group (0.85 ± 0.13 vs. 1.01 ± 0.15, P = 0.004). The DSFR in the most severe nonperfusion area was associates with treatment response in multivariate logistic regression (P = 0.015). CONCLUSION: Deep-superficial flow ratio can represent the relative damage of deep capillary plexus to superficial capillary plexus. Decreased DSFR was found in branch retinal vein occlusion eyes with refractory macular edema.


Assuntos
Angiofluoresceinografia/métodos , Macula Lutea/patologia , Edema Macular/diagnóstico , Oclusão da Veia Retiniana/diagnóstico , Vasos Retinianos/patologia , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Fundo de Olho , Humanos , Edema Macular/etiologia , Masculino , Pessoa de Meia-Idade , Oclusão da Veia Retiniana/complicações , Estudos Retrospectivos
15.
Int Ophthalmol ; 39(12): 2767-2773, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31140024

RESUMO

PURPOSE: To evaluate a surgical technique using a perfluoro-n-octane (PFO)-assisted autologous internal limiting membrane (ILM) plug for refractory macular holes (MHs). METHODS: This study was a retrospective, consecutive, interventional case series. Patients with refractory MHs following PFO-assisted autologous ILM plugs were reviewed between October 1, 2017, and February 28, 2018. The anatomical results of MH preoperatively and postoperatively were evaluated by fundus examination and optical coherence tomography (OCT). The best-corrected visual acuities (BCVAs) before and after surgery were compared as the functional outcome. RESULTS: Six eyes of six consecutive patients with refractory MH were enrolled in this study. Successful MH closure and BCVA improvement after the surgeries were obtained in all eyes. There were four male and two female patients, and the mean age was 63.7 ± 11.1 years. Intraoperatively, the average number of autologous ILM grafts we harvested was 2.2 ± 0.4. The mean follow-up was 6.0 ± 1.7 months. The averaged BCVA before and after the surgery at the last visit improved from 20/356 to 20/153. The ILM graft tissue was still visible, as shown by OCT, in all 6 of 6 (100%) eyes during the follow-up period. CONCLUSIONS: This surgical technique using PFO-assisted autologous ILM plug may provide an option for the treatment of refractory MH.


Assuntos
Membrana Basal/cirurgia , Tamponamento Interno/métodos , Fluorocarbonos/administração & dosagem , Perfurações Retinianas/cirurgia , Vitrectomia/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual
16.
J Cell Mol Med ; 22(8): 3837-3846, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29726584

RESUMO

The biological impact and signalling of epithelial-mesenchymal transition (EMT) during cancer metastasis has been established. However, the changes in biophysical properties of cancer cells undergoing EMT remain elusive. Here, we measured, via video particle tracking microrheology, the intracellular stiffness of head and neck cancer cell lines with distinct EMT phenotypes. We also examined cells migration and invasiveness in different extracellular matrix architectures and EMT-related signalling in these cell lines. Our results show that when cells were cultivated in three-dimensional (3D) environments, the differences in cell morphology, migration speed, invasion capability and intracellular stiffness were more pronounced among different head and neck cancer cell lines with distinct EMT phenotypes than those cultivated in traditional plastic dishes and/or seated on top of a thick layer of collagen. An inverse correlation between intracellular stiffness and invasiveness in 3D culture was revealed. Knock-down of the EMT regulator Twist1 or Snail or inhibition of Rac1 which is a downstream GTPase of Twist1 increased intracellular stiffness. These results indicate that the EMT regulators, Twist1 and Snail and the mediated signals play a critical role in reducing intracellular stiffness and enhancing cell migration in EMT to promote cancer cells invasion.

17.
Biol Reprod ; 98(2): 250-258, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29228121

RESUMO

Bisphenol A (BPA) is an industrial material used for many plastic products and is considered an endocrine disruptor. BPA can be released into the environment and can spread through the food chain. It is well known that BPA exposure leads to lesions, especially in the reproductive system. According to previous studies, BPA reduces newborn numbers in pregnant mice and affects placentation. The placenta is a special endocrine organ during pregnancy. It secretes important hormones, such as progesterone and estrogen, to maintain gestation. In steroid hormone synthesis, two specific enzymes are important: P450scc (CYP11A1) converts cholesterol to pregnenolone and aromatase (CYP19) induces androgen conversion to estrogen.To determine the effects of a low dose of BPA on hormone synthesis in the placenta, we used JEG-3 cells as a model. We found that the steroidogenic genes CYP11A1 and CYP19 were downregulated in human tissues by detectable concentrations of BPA (1-1000 nM), which do not affect cell viability. Furthermore, we demonstrated that BPA influenced the ERK signaling pathway and resulted in hormone reductions. An analysis of trophoblasts in primary culture from a term human placenta showed the same phenomena. Our data demonstrate that treatment with a low dose of BPA does not affect human placental cell survival, but decreases hormone production via to the downregulation of steroidogenic genes and ERK signaling pathway changes.


Assuntos
Compostos Benzidrílicos/farmacologia , Disruptores Endócrinos/farmacologia , Expressão Gênica/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fenóis/farmacologia , Placenta/efeitos dos fármacos , Trofoblastos/efeitos dos fármacos , Aromatase/genética , Aromatase/metabolismo , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Placenta/metabolismo , Gravidez , Trofoblastos/metabolismo
18.
Retina ; 38(5): 900-906, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28437318

RESUMO

PURPOSE: To evaluate the differences in anatomical and visual function changes after macular hole (MH) surgery using the International Vitreomacular Traction Study classification. METHODS: Patients who underwent vitrectomy and blood-assisted internal limiting membrane peeling because of MHs were enrolled in the present study. The patients were divided into three groups according to the sizes of their MHs (small: ≤250 µm, medium: >250 µm and ≤400 µm, and large: >400 µm). The effect of vitreomacular traction on the outcome was also analyzed. All the patients were followed for at least 12 months. The changes in best-corrected visual acuity and the outer retina at the foveal area were monitored using spectral-domain optical coherence tomography. RESULTS: A total of 146 eyes of 146 patients were enrolled. The patients with small MHs showed significantly better mean final visual acuity (mean: 20/58) than patients with large MHs (20/178, P < 0.05). There was no significant difference between patients with small- and medium-sized MHs (20/69). Longitudinal analysis showed that the presence of vitreomacular traction was related to a better restoration of the outer retinal structure and visual acuity. CONCLUSION: Patients with smaller MHs and vitreomacular adhesion had superior final visual acuity and better restoration of the outer retinal structure after MH surgery.


Assuntos
Perfurações Retinianas/cirurgia , Vitrectomia , Descolamento do Vítreo/cirurgia , Idoso , Feminino , Humanos , Macula Lutea/patologia , Masculino , Pessoa de Meia-Idade , Retina/fisiopatologia , Perfurações Retinianas/patologia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
19.
BMC Ophthalmol ; 18(1): 323, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30558558

RESUMO

BACKGROUND: Leber's hereditary optic neuropathy (LHON) is a maternally inherited recessive disease rarely complicated with glaucoma. We conducted a clinical and genetic retrospective case series to describe three cases of juvenile open-angle glaucoma (JOAG) and an ND4 m11778G > A mitochondrial DNA (mtDNA) mutation, which is pathognomonic for LHON. CASE PRESENTATION: Patient 1 was a 16-year-old boy diagnosed with bilateral JOAG and high myopia. His intraocular pressure (IOP) was poorly controlled with the use of full topical anti-glaucoma medications. His best-corrected visual acuity (BCVA) decreased gradually over 5 years. Fundoscopic examination revealed bilateral enlarged disc cupping of the optic nerves with sectorial excavation and reduction of the neural rim in the left eye. His visual field (VF) was characterized by bilateral progressive central scotoma. Pattern visual evoked potentials (VEPs) and pattern electroretinograms (ERGs) showed extinguished responses in both eyes. Because of the non-specific visual field findings and the optic neuropathy disclosed by the pattern VEPs and pattern ERGs, we arranged a genetic test for the patient, which revealed an m11778G > A mtDNA mutation. Patient 2, the younger brother of Patient 1, was a 15-year-old boy who had been diagnosed with bilateral JOAG in 2010. The BCVA of both eyes remained at 1.0 during the follow-up period. Fundoscopic examination revealed bilateral mildly paled optic disc with enlarged cupping and reduction of the neural rim. The pattern ERG revealed a decreased N95 amplitude bilaterally. The genetic test revealed an m11778G > A mtDNA mutation. Patient 3 was a 35-year-old man with bilateral JOAG. His BCVA decreased gradually over 10 years. Fundoscopic examination revealed paled optic disc with enlarged disc cupping and reduction of the neural rim in both eyes. The pattern ERG revealed a decreased N95 amplitude bilaterally. The genetic test revealed an m11778G > A mtDNA mutation. CONCLUSIONS: This case series describes three patients with concomitant occurrence of JOAG and LHON. These two diseases may have a cumulative effect on oxidative stress and retinal ganglion cell death with the rapid deterioration of vision, which may occur during adolescence.


Assuntos
Glaucoma de Ângulo Aberto/genética , NADH Desidrogenase/genética , Atrofia Óptica Hereditária de Leber/genética , Adolescente , Adulto , DNA Mitocondrial/genética , Glaucoma de Ângulo Aberto/etiologia , Humanos , Masculino , Atrofia Óptica Hereditária de Leber/complicações , Estudos Retrospectivos
20.
BMC Ophthalmol ; 18(1): 213, 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30157808

RESUMO

BACKGROUND: To evaluate the surgical technique using autologous retinal graft (ARG) and autologous blood clot (ABC) for the management of refractory macular holes (MHs). METHODS: This study was a retrospective, consecutive, interventional case series. Six eyes of 6 patients who underwent vitrectomy combined with ARG and ABC for the treatment of refractory MH were reviewed. Visual and anatomic outcomes were evaluated. RESULTS: The mean age was 59.0 ± 9.9 years. All cases had multiple vitreoretinal procedures including vitrectomy and gas fluid exchange before patient presentation. The average numbers of vitrectomies were 2.3 ± 0.5, and those of gas fluid exchange were 3 ± 1.7. Closure of the macular hole was achieved in four (66.7%) cases at last follow-up. The mean follow-up time was 25.2 ± 15.6 months. The averaged BCVA before and after 12 months of the surgery improved from 20/591 to 20/244. CONCLUSIONS: This surgical technique using ARG and ABC provide an option for the treatment of refractory MHs.


Assuntos
Sangue , Tamponamento Interno/métodos , Retina/transplante , Perfurações Retinianas/cirurgia , Vitrectomia/métodos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Perfurações Retinianas/diagnóstico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Transplante Autólogo
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