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1.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34531322

RESUMO

Herein, we studied localized electroporation and gene transfection of mammalian cells using a metallodielectric hybrid micromotor that is magnetically and electrically powered. Much like nanochannel-based, local electroporation of single cells, the presented micromotor was expected to increase reversible electroporation yield, relative to standard electroporation, as only a small portion of the cell's membrane (in contact with the micromotor) is affected. In contrast to methods in which the entire membrane of all cells within the sample are electroporated, the presented micromotor can perform, via magnetic steering, localized, spatially precise electroporation of the target cells that it traps and transports. In order to minimize nonselective electrical lysis of all cells within the chamber, resulting from extended exposure to an electrical field, magnetic propulsion was used to approach the immediate vicinity of the targeted cell, after which short-duration, electric-driven propulsion was activated to enable contact with the cell, followed by electroporation. In addition to local injection of fluorescent dye molecules, we demonstrated that the micromotor can enhance the introduction of plasmids into the suspension cells because of the dielectrophoretic accumulation of the plasmids in between the Janus particle and the attached cell prior to the electroporation step. Here, we chose a different strategy involving the simultaneous operation of many micromotors that are self-propelling, without external steering, and pair with cells in an autonomic manner. The locally electroporated suspension cells that are considered to be very difficult to transfect were shown to express the transfected gene, which is of significant importance for molecular biology research.


Assuntos
Eletroporação/métodos , Transfecção/métodos , Animais , Transporte Biológico , Eletricidade , Técnicas de Transferência de Genes , Humanos , Fenômenos Magnéticos , Nanopartículas Multifuncionais/química , Plasmídeos , Análise de Célula Única
2.
Proc Natl Acad Sci U S A ; 118(33)2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34385323

RESUMO

Degradation of a protein by the ubiquitin-proteasome system (UPS) is a multistep process catalyzed by sequential reactions. Initially, ubiquitin is conjugated to the substrate in a process mediated by concerted activity of three enzymes; the last of them-a ubiquitin ligase (E3)-belongs to a family of several hundred members, each recognizing a few specific substrates. This is followed by repeated addition of ubiquitin moieties to the previously conjugated one to generate a ubiquitin chain that serves as a recognition element for the proteasome, which then degrades the substrate. Ubiquitin is recycled via the activity of deubiquitinating enzymes (DUBs). It stands to reason that efficiency of such a complex process would depend on colocalization of the different components in an assembly that allows the reactions to be carried out sequentially and processively. Here we describe nuclear condensates that are dynamic in their composition. They contain p62 as an essential component. These assemblies are generated by liquid-liquid phase separation (LLPS) and also contain ubiquitinated targets, 26S proteasome, the three conjugating enzymes, and DUBs. Under basal conditions, they serve as efficient centers for proteolysis of nuclear proteins (e.g., c-Myc) and unassembled subunits of the proteasome, suggesting they are involved in cellular protein quality control. Supporting this notion is the finding that such foci are also involved in degradation of misfolded proteins induced by heat and oxidative stresses, following recruitment of heat shock proteins and their associated ubiquitin ligase CHIP.


Assuntos
Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ubiquitina/metabolismo , Deleção de Genes , Regulação da Expressão Gênica/fisiologia , Células HeLa , Temperatura Alta , Humanos , Pressão Osmótica , Estresse Oxidativo , Complexo de Endopeptidases do Proteassoma/genética , Proteínas de Ligação a RNA/genética , Estresse Fisiológico , Ubiquitina/genética
3.
Small ; 16(22): e1906682, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32363783

RESUMO

Self-propelling micromotors are emerging as a promising microscale tool for single-cell analysis. The authors have recently shown that the field gradients necessary to manipulate matter via dielectrophoresis can be induced at the surface of a polarizable active ("self-propelling") metallo-dielectric Janus particle (JP) under an externally applied electric field, acting essentially as a mobile floating microelectrode. Here, the application of the mobile floating microelectrode to trap and transport cell organelles in a selective and releasable manner is successfully extended. This selectivity is driven by the different dielectrophoretic (DEP) potential wells on the JP surface that is controlled by the frequency of the electric field, along with the hydrodynamic shearing and size of the trapped organelles. Such selective and directed loading enables purification of targeted organelles of interest from a mixed biological sample while their dynamic release enables their harvesting for further analysis such as gene/RNA sequencing or proteomics. Moreover, the electro-deformation of the trapped nucleus is shown to be in correlation with the DEP force and hence, can act as a promising label-free biomechanical marker. Hence, the active carrier constitutes an important and novel ex vivo platform for manipulation and mechanical probing of subcellular components of potential for single cell analysis.


Assuntos
Eletricidade , Análise de Célula Única , Eletroforese , Hidrodinâmica , Microeletrodos , Organelas
4.
Bioconjug Chem ; 29(8): 2715-2722, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29952546

RESUMO

A larger number of human diseases are related to dysregulation or loss of cellular functions. Effective restoration of the missing or defective cellular functions is highly desirable for fundamental research and therapeutic applications. Inspired by the fantastic feature of cell-derived extracellular vesicles (EVs) that can transport various bioactive molecules between cells, herein, we developed a simple and efficient strategy based on EVs for transferring ion channels to recipient cells, thereby conferring specific biological function to the target cells and regulating the biological events. The constructed channel rhodopsin 2 (ChR2)-loaded EV (EV-ChR2) system can mediate the anchor of light-responsive ion channel ChR2 on the plasma membrane of recipient cells through membrane fusion. Upon blue light irradiation, the ion channel ChR2 was activated and opened, thus permitting the rapid flux of cation ions (e.g., calcium ion) across the plasma membrane of recipient cells. Moreover, the increased Ca2+ in the cytosol could effectively activate Ca2+-dependent transcription factors, further triggering the calcium signaling pathway. This strategy can be extended to modulate other cellular processes and provides a novel insight on the manipulation of biological events.


Assuntos
Vesículas Extracelulares/metabolismo , Canais Iônicos/metabolismo , Rodopsina/metabolismo , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Membrana Celular/metabolismo , Células HEK293 , Humanos , Transporte de Íons , Luz , Camundongos , Células NIH 3T3 , Transporte Proteico
5.
Biotechnol Bioeng ; 115(11): 2828-2843, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30102771

RESUMO

Treating systemic metastases at the micrometastatic stage is a potential strategy to inhibit cancer metastasis. This study aims to establish an apoptosis sensor-based platform for rapid, effective, and noninvasive identification of drugs that can inhibit the proliferation of micrometastatic cancer cells. We stably transfected the plasmid DNA encoding the fluorescence resonance energy transfer-based caspase-3 sensor into highly metastatic melanoma B16F10 cells. The resulting B16F10-C3 cells were applied for screening of antiproliferative and proapoptotic drugs in two-dimensional (2D) monolayer, three-dimensional (3D) spheroids, and zebrafish xenotransplantation tumors. All studies were conducted in 96-well plates in a high throughput manner. Fourteen compounds including six chemotherapeutic drugs and eight kinase inhibitors were tested. Thirteen compounds failed the tests due to: Drug resistance, low efficacy, poor pharmacokinetic profile, and/or high side effects to zebrafish. The only compound that passed all tests was pan-phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002, which inhibited the proliferation of B16F10-C3 cells in both 2D and 3D cultures. More important, it significantly reduced the xenograft tumor size in zebrafish by decreasing the viability of metastatic cancer cells. Our study suggests that the PI3K/AKT pathway is a potential therapeutic target for the reactivation of tumor dormancy and proliferation of micrometastases. Moreover, this integrated approach is effective for rapid identification of systemic antimetastases drugs.


Assuntos
Antineoplásicos/isolamento & purificação , Caspase 3/análise , Cromonas/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos/métodos , Morfolinas/isolamento & purificação , Metástase Neoplásica/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Apoptose , Técnicas Biossensoriais/métodos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromonas/administração & dosagem , Cromonas/farmacologia , Modelos Animais de Doenças , Transferência Ressonante de Energia de Fluorescência , Humanos , Melanoma/tratamento farmacológico , Melanoma/secundário , Modelos Teóricos , Morfolinas/administração & dosagem , Morfolinas/farmacologia , Esferoides Celulares , Fatores de Tempo , Transplante Heterólogo , Células Tumorais Cultivadas , Peixe-Zebra
6.
Biotechnol Bioeng ; 112(8): 1673-82, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25728592

RESUMO

Two-dimensional (2D) cultures are commonly used for testing drug effects largely because of their easy maintenance. But they do not represent the spatial interactions of the cells within a tumor. Three-dimensional (3D) cultures can overcome those limitations thus mimicking the architecture of solid tumor. However, it is not easy to evaluate drug effects in 3D culture for a long time. This necessitates the development of a real-time and longitudinal analysis of 3D platforms. In this study, we transfected the plasmid DNA encoding the fluorescence resonance energy transfer (FRET)-based biosensor into human breast cancer cells and generated two cell lines of MCF7-C3 and MDA-MB-231-C3 (231-C3) cells. We used them to determine the activation of caspase-3, whereby healthy cells appear green and apoptotic cells appear blue by FRET imaging. As the caspase sensors can be constantly produced within the cells and quickly respond to caspase activation, we hypothesized that these sensor cells will allow longitudinal detection of apoptosis. MCF7-C3 and 231-C3 spheroids were generated and subjected to histological examination, gene expression studies, drug treatment, and FRET analyses. Our results demonstrated that MCF7-C3 cells formed tight 3D spheroids, and mimicked in vivo tumor architecture. The mRNA level of tumorigenic markers such as MMP-9, SOX2, and OCT4A were much higher in cells cultured in 3D than in 2D. Finally, upon treatment with paclitaxel, the FRET effect was reduced at the rim of MCF7-C3 spheroids in a dose and time-dependent manner demonstrating these sensor cells can be used to determine drug-induced apoptosis in a 3D set up. This study supports the possibility of developing a biosensor-based in vitro 3D breast tumor model for determination of anti-cancer drug penetration over a long course of time in a non-invasive manner.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Técnicas Biossensoriais/métodos , Transferência Ressonante de Energia de Fluorescência , Neoplasias da Mama , Linhagem Celular Tumoral , Humanos , Modelos Biológicos , Técnicas de Cultura de Órgãos
7.
Adv Sci (Weinh) ; 10(8): e2204931, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36507618

RESUMO

Electrically powered micro- and nanomotors are promising tools for in vitro single-cell analysis. In particular, single cells can be trapped, transported, and electroporated by a Janus particle (JP) using an externally applied electric field. However, while dielectrophoretic (DEP)-based cargo manipulation can be achieved at high-solution conductivity, electrical propulsion of these micromotors becomes ineffective at solution conductivities exceeding ≈0.3 mS cm-1 . Here, JP cargo manipulation and transport capabilities to conductive near-physiological (<6 mS cm-1 ) solutions are extended successfully by combining magnetic field-based micromotor propulsion and navigation with DEP-based manipulation of various synthetic and biological cargos. Combination of a rotating magnetic field and electric field results in enhanced micromotor mobility and steering control through tuning of the electric field frequency. In addition, the micromotor's ability of identifying apoptotic cell among viable and necrotic cells based on their dielectrophoretic difference is demonstrated, thus, enabling to analyze the apoptotic status in the single-cell samples for drug discovery, cell therapeutics, and immunotherapy. The ability to trap and transport live cells towards regions containing doxorubicin-loaded liposomes is also demonstrated. This hybrid micromotor approach for label-free trapping, transporting, and sensing of selected cells within conductive solutions opens new opportunities in drug delivery and single-cell analysis, where close-to-physiological media conditions are necessary.


Assuntos
Sistemas de Liberação de Medicamentos , Campos Magnéticos , Condutividade Elétrica , Análise de Célula Única , Doxorrubicina
8.
Biochem Biophys Res Commun ; 418(4): 641-6, 2012 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-22290227

RESUMO

In this study, we developed a high-throughput endothelial cell apoptosis assay using a fluorescence resonance energy transfer (FRET)-based biosensor. After exposure to apoptotic inducer UV-irradiation or anticancer drugs such as paclitaxel, the fluorescence of the cells changed from green to blue. We developed this method into a high-throughput assay in 96-well plates by measuring the emission ratio of yellow fluorescent protein (YFP) to cyan fluorescent protein (CFP) to monitor the activation of a key protease, caspase-3, during apoptosis. The Z' factor for this assay was above 0.5 which indicates that this assay is suitable for a high-throughput analysis. Finally, we applied this functional high-throughput assay for screening vascular disrupting agents (VDA) which could induce endothelial cell apoptosis from our in-house compounds library and dioscin was identified as a hit. As this assay allows real time and sensitive detection of cell apoptosis, it will be a useful tool for monitoring endothelial cell apoptosis in living cell situation and for identifying new VDA candidates via a high-throughput screening.


Assuntos
Inibidores da Angiogênese/isolamento & purificação , Apoptose/efeitos dos fármacos , Descoberta de Drogas/métodos , Transferência Ressonante de Energia de Fluorescência/métodos , Ensaios de Triagem em Larga Escala , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Inibidores da Angiogênese/farmacologia , Técnicas Biossensoriais , Caspase 3/análise , Caspase 3/biossíntese , Linhagem Celular , Células Endoteliais da Veia Umbilical Humana/enzimologia , Células Endoteliais da Veia Umbilical Humana/efeitos da radiação , Humanos , Paclitaxel/farmacologia , Raios Ultravioleta
9.
Int J Biol Sci ; 18(3): 1120-1133, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35173543

RESUMO

Resistance to doxorubicin (DOX) remains a big challenge to breast cancer treatment especially for triple negative breast cancer (TNBC). Our previous study revealed that the antioxidant system plays an important role in conferring metastasis derived DOX resistance. In this study, we used two-dimensional difference gel electrophoresis (2D-DIGE) proteomics to compare the expression profiles of two generations of TNBC cell lines which have increased metastatic ability in nude mice and exhibited resistance to DOX. Through careful analyses, one antioxidant protein: glucose-6-phosphate dehydrogenase (G6PD) was identified with 3.2-fold higher level in metastatic/DOX-resistant 231-M1 than its parental 231-C3 cells. Analyses of clinical data showed that TNBC patients with higher G6PD levels exhibited lower overall survival than patients with lower G6PD level. Reducing G6PD expression by siRNA or inhibiting its activity with dehydroepiandrosterone (DHEA) significantly increased DOX's cytotoxicity in both cell lines. Importantly, inhibiting G6PD's activity with DHEA dramatically increased the apoptotic rate of 1.25 µM DOX from 2% to 54%. Our results suggest that high level of G6PD can help TNBC to resist DOX-induced oxidative stress. Thus, inhibiting G6PD shall be a good strategy to treat DOX-resistant TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Animais , Antioxidantes/uso terapêutico , Linhagem Celular Tumoral , Desidroepiandrosterona/uso terapêutico , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/uso terapêutico , Humanos , Camundongos , Camundongos Nus , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo
10.
Mol Cell Oncol ; 8(5): 1989939, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34859148

RESUMO

Membraneless condensates have recently caught the attention of biologists as hubs for cellular components required for catalysis of basic processes. Whether they are real has become the center of heated discussion where the main issues are their mechanism of assembly and function. A recent study describing these condensates as hubs for protein degradation by the ubiquitin system may shed a new light on this recent development in cell biology.

11.
Proteomics ; 10(7): 1474-83, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20127691

RESUMO

Honokiol (HNK), a natural small molecular product, inhibited proliferation of HepG2 cells and exhibited anti-tumor activity in nude mice. In this article, we applied a novel sensitive stable isotope labeling with amino acids in cell culture-based quantitative proteomic method and a model of nude mice to investigate the correlation between HNK and the hotspot migration molecule Ras GTPase-activating-like protein (IQGAP1). The quantitative proteomic analysis showed that IQGAP1 was 0.53-fold down-regulated under 10 microg/mL HNK exposure for 24 h on HepG2 cells. Migration ability of HepG2 cells under HNK treatment was correlated with its expression level of IQGAP1. In addition, the biochemical validation on HepG2 cells and the tumor xenograft model further demonstrated that HNK decreased the expression level of IQGAP1 and its upstream proteins Cdc42/Rac1. These data supported that HNK can modulate cell adhesion and cell migration by acting on Cdc42/Rac1 signaling via IQGAP1 interactions with its upstream Cdc42/Rac1 proteins, which is a new molecular mechanism of HNK to exert its anti-tumor activity.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Compostos de Bifenilo/farmacologia , Movimento Celular/efeitos dos fármacos , Lignanas/farmacologia , Proteômica/métodos , Proteínas Ativadoras de ras GTPase/biossíntese , Animais , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Histocitoquímica , Humanos , Marcação por Isótopo , Camundongos , Camundongos Nus , Proteoma/efeitos dos fármacos , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Carga Tumoral , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas Ativadoras de ras GTPase/genética
12.
Int J Cancer ; 127(10): 2455-66, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20162567

RESUMO

Deguelin, a rotenoid of the flavonoid family, has been reported to possess antiproliferative and anticarcinogenic activities in several cell lines and tumor models. However, it is still unclear whether deguelin effectively inhibits tumor-associated lymphangiogenesis and lymphatic metastasis. Since tumor production of vascular endothelial cell growth factor (VEGF)-D was associated with tumor lymphangiogenesis and lymphatic metastasis, we established the mouse lymphatic metastasis model by transfecting high expression VEGF-D into LL/2 Lewis lung cells (VEGF-D-LL/2) and explored the effects of deguelin on lymphatic metastasis in the immunocompetent C57BL/6 mice. Our results indicated that deguelin inhibited proliferation, migration of VEGF-D-LL/2 cells via downregulating AKT and mitogen-activated protein kinase pathway and interfered tube formation of lymphatic vascular endothelial cells on matrigel at nanomolar concentrations. Deguelin significantly downregulated the expression of VEGF-D both at mRNA and protein levels in VEGF-D-LL/2 cells in a dose-dependent manner. In the in vivo study, intraperitoneal administration of deguelin (4 mg/kg) remarkably inhibited the tumor-associated lymphangiogenesis and lymphatic metastasis. The rates of lymph node and lung metastasis in deguelin-treated mice were 0 and 16.7% compared with 58.3 and 83.3% in control group mice, respectively. Deguelin also resulted in a remarkable delay of tumor growth and prolongation of life span. Immunohistochemical staining with antibodies against VEGF-D, LYVE-1 and VEGFR-3 revealed fewer positive vessel-like structures in deguelin-treated mice compared with control group mice. Taken together, we demonstrate for the first time that deguelin suppresses tumor-associated lymphangiogenesis and lymphatic metastasis by downregulation of VEGF-D both in vitro and in vivo.


Assuntos
Carcinoma Pulmonar de Lewis/tratamento farmacológico , Células Endoteliais/efeitos dos fármacos , Rotenona/análogos & derivados , Fator D de Crescimento do Endotélio Vascular/metabolismo , Animais , Carcinoma Pulmonar de Lewis/irrigação sanguínea , Carcinoma Pulmonar de Lewis/patologia , Processos de Crescimento Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Humanos , Linfangiogênese/efeitos dos fármacos , Metástase Linfática , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Rotenona/farmacologia , Fator D de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator D de Crescimento do Endotélio Vascular/biossíntese , Fator D de Crescimento do Endotélio Vascular/genética
13.
Chemistry ; 16(17): 5129-37, 2010 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-20349475

RESUMO

We herein present an effective strategy to create water-soluble fluorescent bioimaging dyes by introducing the imidazolium-based ionic liquid (IL) pendants into a fluorescent skeleton. A new type of water-soluble imidazolium-anchored squaraine dye was synthesized accordingly. The relationship between the aggregate of squaraines and their fluorescent cell imaging application was elucidated in detail. Firstly, the aggregation behavior of squaraines in water solutions could be suppressed by varying the alkyl chain attached to the imidazolium unit. Secondly, the capability of cellular uptake and staining of dyes was also dramatically enhanced upon increasing the length of the paraffinic chain. These squaraine dyes displayed an excellent photostability that could permit real-time fluorescence bioimaging experiments to be monitored over a long time period with constant sample irradiation. Additionally, we designed for the first time an Fe(II)-ion probe on the basis of an attack of the hydroxyl radical to the four-membered ring of squaraine. The results demonstrated that the imidazolium-anchored squaraines could perform "naked-eye" detection of the Fe(2+) ion over a wide range of other interfering metals in aqueous media. More surprisingly, this process showed a fluorescence "turn-off" and "-on" response through the regeneration of squaraines in cells.


Assuntos
Ciclobutanos/química , Corantes Fluorescentes/síntese química , Hidrocarbonetos Bromados/síntese química , Imidazóis/síntese química , Fenóis/química , Compostos Ferrosos/análise , Compostos Ferrosos/química , Corantes Fluorescentes/química , Células HeLa , Células Hep G2 , Humanos , Hidrocarbonetos Bromados/química , Imidazóis/química , Líquidos Iônicos , Estrutura Molecular , Solubilidade , Espectrometria de Fluorescência/métodos , Células Tumorais Cultivadas , Cordão Umbilical/citologia , Água
14.
Sci Adv ; 6(5): eaay4412, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32064350

RESUMO

Self-propelling micromotors are emerging as a promising micro- and nanoscale tool for single-cell analysis. We have recently shown that the field gradients necessary to manipulate matter via dielectrophoresis can be induced at the surface of a polarizable active ("self-propelling") metallodielectric Janus particle (JP) under an externally applied electric field, acting essentially as a mobile floating microelectrode. Here, we successfully demonstrated that the application of an external electric field can singularly trap and transport bacteria and can selectively electroporate the trapped bacteria. Selective electroporation, enabled by the local intensification of the electric field induced by the JP, was obtained under both continuous alternating current and pulsed signal conditions. This approach is generic and applicable to bacteria and JP, as well as a wide range of cell types and micromotor designs. Hence, it constitutes an important and novel experimental tool for single-cell analysis and targeted delivery.


Assuntos
Campos Eletromagnéticos , Eletroporação , Nanopartículas Multifuncionais/química , Análise de Célula Única , Bactérias/química , Bactérias/efeitos da radiação , Polaridade Celular , Eletricidade , Microeletrodos , Propriedades de Superfície
16.
Int J Cancer ; 124(11): 2709-18, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19219913

RESUMO

Lymph nodes metastasis of tumor could be a crucial early step in the metastatic process. Induction of tumor lymphangiogenesis by vascular endothelial growth factor-D may play an important role in promoting tumor metastasis to regional lymph nodes and these processes can be inhibited by inactivation of the VEGFR-3 signaling pathway. Honokiol has been reported to possess potent antiangiogenesis and antitumor properties in several cell lines and xenograft tumor models. However, its role in tumor-associated lymphangiogenesis and lymphatic metastasis remains unclear. Here, we established lymph node metastasis models by injecting overexpressing VEGF-D Lewis lung carcinoma cells into C57BL/6 mice to explore the effect of honokiol on tumor-associated lymphangiogenesis and related lymph node metastasis. The underlying mechanisms were systematically investigated in vitro and in vivo. In in vivo study, liposomal honokiol significantly inhibited the tumor-associated lymphangiogenesis and metastasis in Lewis lung carcinoma model. A remarkable delay of tumor growth and prolonged life span were also observed. In in vitro study, honokiol inhibited VEGF-D-induced survival, proliferation and tube-formation of both human umbilical vein endothelial cells (HUVECs) and lymphatic vascular endothelial cells (HLECs). Western blotting analysis showed that liposomal honokiol-inhibited Akt and MAPK phosphorylation in 2 endothelial cells, and downregulated expressions of VEGFR-2 of human vascular endothelial cells and VEGFR-3 of lymphatic endothelial cells. Thus, we identified for the first time that honokiol provided therapeutic benefit not only by direct effects on tumor cells and antiangiogenesis but also by inhibiting lymphangiogenesis and metastasis via the VEGFR-3 pathway. The present findings may be of importance to investigate the molecular mechanisms underlying the spread of cancer via the lymphatics and explore the therapeutical strategy of honokiol on antilymphangiogenesis and antimetastasis.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Compostos de Bifenilo/administração & dosagem , Lignanas/administração & dosagem , Linfangiogênese/efeitos dos fármacos , Metástase Linfática/prevenção & controle , Fator D de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/farmacologia , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Feminino , Humanos , Lignanas/farmacologia , Lipossomos , Camundongos , Camundongos Endogâmicos C57BL , Fator D de Crescimento do Endotélio Vascular/fisiologia , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Mol Cancer Ther ; 7(6): 1588-97, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18566229

RESUMO

Human alpha-defensin-1 (HNP1), a small antimicrobial peptide, shows cytotoxicity to tumor cells in vitro and inhibitory activity for pathologic neovascularization in vivo. Here, we did a gene therapy with a plasmid that expresses a secretable form of HNP1 for assaying its antitumor activity. The expression and secretion of HNP1 were determined by reverse transcription-PCR and ELISA in vitro. We found that expression of HNP1 in A549 tumor cells caused significant growth inhibition. This effect is most likely cell autonomous, as a significant amount of recombinant HNP1 protein was found to be accumulated in the cytoplasm by immunohistochemical staining using an anti-HNP1 antibody and the supernatant containing secreted HNP1 failed to produce any noticeable antitumor activity. Flow cytometry and Hoechst 33258 staining showed that the number of apoptotic cells among the A549 cells expressing recombinant HNP1 proteins was significantly greater than that of the nontransfected control cultures, suggesting that this growth-inhibitory activity was due to an apoptotic mechanism triggered by the intracellular HNP1. The antitumor activity of intracellularly expressed HNP1 was also shown in vivo. Decreased microvessel density and increased lymphocyte infiltration were observed in tumor tissue from HNP1-treated mice through histologic analysis. These results indicate that intracellularly expressed HNP1 induces tumor cell apoptosis, which inhibits tumor growth. The antiangiogenesis effect of HNP1 may contribute to its inhibitory activity in vivo, and HNP1 might involve the host immune response to tumor. These findings provide a rationale for developing HNP1-based gene therapy for cancer.


Assuntos
Adenocarcinoma/patologia , Neoplasias Pulmonares/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , alfa-Defensinas/metabolismo , Animais , Células COS , Morte Celular , Linhagem Celular Tumoral , Proliferação de Células , Chlorocebus aethiops , Humanos , Espaço Intracelular/metabolismo , Camundongos , Camundongos Nus , Neovascularização Patológica , Aumento de Peso
18.
J Biophotonics ; 12(6): e201800367, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30701677

RESUMO

Graphene quantum dots (GQDs), the new zero-dimensional carbon nanomaterial, have been demonstrated as a promising material for biomedical applications due to its good biocompatibility and low toxicity. However, the integration of multiple therapeutic approaches into a nanosized platform based on the GQD has not been explored yet to our best knowledge. In this report, we regulate the generation of reactive oxygen species (ROS) when using the GQD as a photosensitizer by varying the doping amount of nitrogen atoms to achieve efficiency controllable photodynamic therapy. On the other hand, charge-reversal (3-Aminopropyl) triethoxysilane (APTES) was used to conjugate on the surface of GQD for nucleus targeting drug delivery for the first time. The treatment outcome of produced ROS and nucleus-targeting drug delivery was investigated by fluorescence imaging. The results demonstrated that the N-GQD-DOX-APTES in dual roles as a drug carrier and photosensitizer could achieve nucleus-targeting delivery and strong ROS production simultaneously. This approach provides a promising strategy for the development of multifunctional therapy in one nano platform for biomedical applications.


Assuntos
Núcleo Celular/metabolismo , Portadores de Fármacos/química , Grafite/química , Fotoquimioterapia , Pontos Quânticos/química , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Humanos , Propilaminas/química , Silanos/química
19.
J Cancer Res Clin Oncol ; 134(9): 937-45, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18350317

RESUMO

PURPOSE: Honokiol has been receiving attention as an anticancer agent because of its anti-tumor effect. In the current study, we encapsulated honokiol with liposome and tested it on cisplatin-sensitive (A2780s) and -resistant (A2780cp) human ovarian cancer models. METHODS: The anti-tumor activity of liposomal honokiol (Lipo-HNK) was evaluated in nude mice bearing A2780s and A2780cp s.c. tumors. Mice were treated twice weekly with i.v. administration of Lipo-HNK (10 mg/kg), control liposome (10 mg/kg), 0.9% NaCl solution or weekly with intraperitoneally administered cisplatin (5 mg/kg) for 3 weeks. Tumor volume and survival time were observed. Assessment of apoptotic cells by TUNEL assay was conducted in tumor tissue. Microvessel density within tumor tissue was determined by CD34 immunohistochemistry. For in vitro study, induction of apoptosis by Lipo-HNK was examined by PI staining fluorescence microscopy, DNA fragmentation assay and flow cytometric analysis. RESULTS: Administration of Lipo-HNK resulted in significant inhibition (84-88% maximum inhibition relative to controls) in the growth of A2780s and A2780cp tumor xenografts and prolonged the survival of the treated mice. These anti-tumor responses were associated with marked increases in tumor apoptosis, and reductions in intratumoral microvessel density. CONCLUSIONS: The present findings suggest that Lipo-HNK may provide an effective approach to inhibit tumor growth in both cisplatin sensitive and -resistant human ovarian cancer with minimal side effects.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Compostos de Bifenilo/farmacologia , Cisplatino/farmacologia , Lignanas/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Compostos de Bifenilo/uso terapêutico , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Imuno-Histoquímica , Lignanas/uso terapêutico , Lipossomos , Camundongos , Camundongos Nus , Neoplasias Ovarianas/patologia
20.
J Chromatogr A ; 1178(1-2): 101-7, 2008 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-18082754

RESUMO

Both analytical and preparative high-speed counter-current chromatography (HSCCC) were used to isolate and separate chemical bioactive constituents from the seeds of Millettia pachycarpa Benth, a famous traditional Chinese medicine. Three rotenoids and one isoflavone were successfully purified for the first time by HSCCC with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (HEMWat) (1:0.8:1:0.6, v/v/v/v). The separation parameters were first performed on the analytical HSCCC and optimized conditions were then scaled up to preparative HSCCC. The separation produced 160.2 mg tephrosin, 14.6 mg 4',5'-dimethoxy-6,6-dimethylpyranoisoflavone, 109.4 mg deguelin, 6.7 mg 6a,12a-dehydrodeguelin with respective purities of 95, 93, 95, 95%, in one single run from 400 mg crude extract of the seeds of M. pachycarpa Benth. The purity of the isolated compounds was analyzed by high-performance liquid chromatography (HPLC) and their structures were identified by electrospray ionization mass spectrometry (ESI-MS); (1)H nuclear magnetic resonance ((1)H NMR) and (13)C nuclear magnetic resonance ((13)C NMR) analysis. This paper is an excellent example of the role that CCC is playing in isolating active compounds for pre-clinical trials of new chemical entities, even when scaling up between centrifuges from different manufacturers.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromonas/isolamento & purificação , Distribuição Contracorrente , Isoflavonas/isolamento & purificação , Millettia/química , Piranos/isolamento & purificação , Rotenona/análogos & derivados , Cromonas/análise , Cromonas/química , Isoflavonas/análise , Isoflavonas/química , Espectroscopia de Ressonância Magnética , Piranos/análise , Piranos/química , Rotenona/análise , Rotenona/química , Rotenona/isolamento & purificação , Sementes/química , Espectrometria de Massas por Ionização por Electrospray
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