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1.
J Cell Mol Med ; 28(14): e18533, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39034442

RESUMO

Hepatitis B Virus (HBV) infection significantly elevates the risk of hepatocellular carcinoma (HCC), with the HBV X protein (HBx) playing a crucial role in cancer progression. Sorafenib, the primary therapy for advanced HCC, shows limited effectiveness in HBV-infected patients due to HBx-related resistance. Numerous studies have explored combination therapies to overcome this resistance. Sodium diethyldithiocarbamate (DDC), known for its anticancer effects and its inhibition of superoxide dismutase 1 (SOD1), is hypothesized to counteract sorafenib (SF) resistance in HBV-positive HCCs. Our research demonstrates that combining DDC with SF significantly reduces HBx and SOD1 expressions in HBV-positive HCC cells and human tissues. This combination therapy disrupts the PI3K/Akt/mTOR signalling pathway and promotes apoptosis by increasing reactive oxygen species (ROS) levels. These cellular changes lead to reduced tumour viability and enhanced sensitivity to SF, as evidenced by the synergistic suppression of tumour growth in xenograft models. Additionally, DDC-mediated suppression of SOD1 further enhances SF sensitivity in HBV-positive HCC cells and xenografted animals, thereby inhibiting cancer progression more effectively. These findings suggest that the DDC-SF combination could serve as a promising strategy for overcoming SF resistance in HBV-related HCC, potentially optimizing therapy outcomes.


Assuntos
Carcinoma Hepatocelular , Vírus da Hepatite B , Neoplasias Hepáticas , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Espécies Reativas de Oxigênio , Transdução de Sinais , Sorafenibe , Superóxido Dismutase-1 , Serina-Treonina Quinases TOR , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/virologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/virologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Superóxido Dismutase-1/metabolismo , Superóxido Dismutase-1/genética , Animais , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Camundongos , Vírus da Hepatite B/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Apoptose/efeitos dos fármacos , Hepatite B/complicações , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Ditiocarb/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Camundongos Nus , Proliferação de Células/efeitos dos fármacos , Transativadores , Proteínas Virais Reguladoras e Acessórias
2.
Biochem Biophys Res Commun ; 730: 150369, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-39013264

RESUMO

Gemcitabine is a nucleoside analog widely used as an anticancer agent against several types of cancer. Although gemcitabine sometimes shows excellent effectiveness, cancer cells are often poorly responsive to or resistant to the drug. Recently, specific strains or dysbiosis of the human microbiome were correlated with drug reactivity and resistance acquisition. Therefore, we aimed to identify antibiotic compounds that can modulate the microbiome to enhance the responsiveness to gemcitabine. To achieve this, we confirmed the gemcitabine responsiveness based on public data and conducted drug screening on a set of 250 antibiotics compounds. Subsequently, we performed experiments to investigate whether the selected compounds could enhance the responsiveness to gemcitabine. First, we grouped a total of seven tumor cell lines into resistant and sensitive group based on the IC50 value (1 µM) of gemcitabine obtained from the public data. Second, we performed high-throughput screening with compound treatments, identifying seven compounds from the resistant group and five from the sensitive group based on dose dependency. Finally, the combination of the selected compound, puromycin dihydrochloride, with gemcitabine in gemcitabine-resistant cell lines resulted in extensive cell death and a significant increase in cytotoxic efficacy. Additionally, mRNA levels associated with cell viability and stemness were reduced. Through this study, we screened antibiotics to further improve the efficacy of existing anticancer drugs and overcome resistance. By combining existing anticancer agents and antibiotic substances, we hope to establish various drug combination therapies and ultimately improve cancer treatment efficacy.

3.
Microvasc Res ; 155: 104698, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38801943

RESUMO

Angiogenesis is mainly regulated by the delivery of VEGF-dependent signaling to cells. However, the angiogenesis mechanism regulated by VEGF-induced miRNA is still not understood. After VEGF treatment in HUVECs, we screened the changed miRNAs through small-RNA sequencing and found VEGF-induced miR-4701-3p. Furthermore, the GFP reporter gene was used to reveal that TOB2 expression was regulated by miR-4701-3p, and it was found that TOB2 and miR-4701-3p modulation could cause angiogenesis in an in-vitro angiogenic assay. Through the luciferase assay, it was confirmed that the activation of the angiogenic transcription factor MEF2 was regulated by the suppression and overexpression of TOB2 and miR-4701-3p. As a result, MEF2 downstream gene mRNAs that induce angiogenic function were regulated. We used the NCBI GEO datasets to reveal that the expression of TOB2 and MEF2 was significantly changed in cardiovascular disease. Finally, it was confirmed that the expression of circulating miR-4701-3p in the blood of myocardial infarction patients was remarkably increased. In patients with myocardial infarction, circulating miR-4701-3p was increased regardless of age, BMI, and sex, and showed high AUC levels in specificity and sensitivity analysis (AUROC) (AUC = 0.8451, 95 % CI 0.78-0.90). Our data showed TOB2-mediated modulation of MEF2 and its angiogenesis by VEGF-induced miR-4701-3p in vascular endothelial cells. In addition, through bioinformatics analysis using GEO data, changes in TOB2 and MEF2 were revealed in cardiovascular disease. We suggest that circulating miR-4701-3p has high potential as a biomarker for myocardial infarction.

4.
Opt Express ; 31(8): 12162-12174, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157381

RESUMO

Hyperlenses offer an appealing opportunity to unlock bioimaging beyond the diffraction limit with conventional optics. Mapping hidden nanoscale spatiotemporal heterogeneities of lipid interactions in live cell membrane structures has been accessible only using optical super-resolution techniques. Here, we employ a spherical gold/silicon multilayered hyperlens that enables sub-diffraction fluorescence correlation spectroscopy at 635 nm excitation wavelength. The proposed hyperlens enables nanoscale focusing of a Gaussian diffraction-limited beam below 40 nm. Despite the pronounced propagation losses, we quantify energy localization in the hyperlens inner surface to determine fluorescence correlation spectroscopy (FCS) feasibility depending on hyperlens resolution and sub-diffraction field of view. We simulate the diffusion FCS correlation function and demonstrate the reduction of diffusion time of fluorescent molecules up to nearly 2 orders of magnitude as compared to free space excitation. We show that the hyperlens can effectively distinguish nanoscale transient trapping sites in simulated 2D lipid diffusion in cell membranes. Altogether, versatile and fabricable hyperlens platforms display pertinent applicability for the enhanced spatiotemporal resolution to reveal nanoscale biological dynamics of single molecules.

5.
Nucleic Acids Res ; 49(4): 2390-2399, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33544854

RESUMO

CRISPR-based base editors (BEs) are widely used to induce nucleotide substitutions in living cells and organisms without causing the damaging DNA double-strand breaks and DNA donor templates. Cytosine BEs that induce C:G to T:A conversion and adenine BEs that induce A:T to G:C conversion have been developed. Various attempts have been made to increase the efficiency of both BEs; however, their activities need to be improved for further applications. Here, we describe a fluorescent reporter-based drug screening platform to identify novel chemicals with the goal of improving adenine base editing efficiency. The reporter system revealed that histone deacetylase inhibitors, particularly romidepsin, enhanced base editing efficiencies by up to 4.9-fold by increasing the expression levels of proteins and target accessibility. The results support the use of romidepsin as a viable option to improve base editing efficiency in biomedical research and therapeutic genome engineering.


Assuntos
Adenina , Sistemas CRISPR-Cas , Edição de Genes , Inibidores de Histona Desacetilases/farmacologia , Depsipeptídeos/farmacologia , Doxiciclina/farmacologia , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Células HEK293 , Células HeLa , Humanos , Substâncias Luminescentes/análise , Biossíntese de Proteínas , RNA/biossíntese
6.
Opt Express ; 30(23): 42663-42677, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366716

RESUMO

Conventional photon detectors necessarily face critical challenges regarding strong wavelength-selective response and narrow spectral bandwidth, which are undesirable for spectroscopic applications requiring a wide spectral range. With this perspective, herein, we overcome these challenges through a free-carrier absorption-based waveguide-integrated bolometer for infrared spectroscopic sensors on a silicon-on-insulator (SOI) platform featuring a spectrally flat response at near-infrared (NIR) range (1520-1620 nm). An in-depth thermal analysis was conducted with a systematic investigation of geometry dependence on the detectors. We achieved great performances: temperature coefficient of resistance (TCR) of -3.786%/K and sensitivity of -26.75%/mW with a low wavelength dependency, which are record-high values among reported waveguide bolometers so far, to our knowledge. In addition, a clear on-off response with the rise/fall time of 24.2/29.2 µs and a 3-dB roll-off frequency of ∼22 kHz were obtained, sufficient for a wide range of sensing applications. Together with the possibility of expanding an operation range to the mid-infrared (MIR) band, as well as simplicity in the detector architecture, our work here presents a novel strategy for integrated photodetectors covering NIR to MIR at room temperature for the development of the future silicon photonic sensors with ultrawide spectral bandwidth.

7.
Biochem Biophys Res Commun ; 539: 48-55, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33421768

RESUMO

CRISPR-Cas systems, including Cas9 and Cpf1 (Cas12a), are promising tools for generating gene knockout mouse models. Unlike Cas9, Cpf1 can generate multiple crRNAs from a single concatemeric crRNA precursor, which is favorable for multiplex gene editing. Recently, a hybrid guide RNA (hgRNA) system employing both Cas9 and Cpf1 was developed for multiplex gene editing. As the crRNA of Cpf1 was linked to the 3' end of the sgRNA for Cas9, it can be split into separate guide RNAs by Cpf1. To examine whether this Cas9-Cpf1 hybrid system is suitable for multiplex gene knockouts in the mouse embryo, we generated an hgRNA that simultaneously targets the mouse Il10ra gene by Cas9 and mouse Dr3 (or Tnfrsf25, death receptor3) gene by Cpf1. The expression of hgRNA from a single promoter induced significant indels at each gene in cultured mouse cells upon the co-expression of both Cas9 and Cpf1. Interestingly, the hgRNA exhibited comparable Cas9-mediated indel activity without Cpf1 expression. Similarly, when the hgRNA was co-microinjected with both Cas9 and Cpf1 mRNAs into mouse zygotes at the pronuclear stage, founder mice were generated harboring mutations in both the Il10ra and Dr3 genes. However, when Cas9 mRNA was used alone without Cpf1 mRNA, the mouse Il10ra gene targeting was significantly decreased. These results indicate that the hgRNA system is a possible tool for multiplex gene targeting in the mouse embryo.


Assuntos
Proteína 9 Associada à CRISPR/metabolismo , Embrião de Mamíferos/metabolismo , Endonucleases/metabolismo , Edição de Genes , Marcação de Genes/métodos , RNA Guia de Cinetoplastídeos/metabolismo , Animais , Linhagem Celular , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , RNA Guia de Cinetoplastídeos/genética
8.
Sensors (Basel) ; 21(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206760

RESUMO

Chiral materials, which show different optical behaviors when illuminated by left or right circularly polarized light due to broken mirror symmetry, have greatly impacted the field of optical sensing over the past decade. To improve the sensitivity of chiral sensing platforms, enhancing the chiroptical response is necessary. Metasurfaces, which are two-dimensional metamaterials consisting of periodic subwavelength artificial structures, have recently attracted significant attention because of their ability to enhance the chiroptical response by manipulating amplitude, phase, and polarization of electromagnetic fields. Here, we reviewed the fundamentals of chiroptical metasurfaces as well as categorized types of chiroptical metasurfaces by their intrinsic or extrinsic chirality. Finally, we introduced applications of chiral metasurfaces such as multiplexing metaholograms, metalenses, and sensors.

9.
Phys Chem Chem Phys ; 22(4): 2337-2342, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31932814

RESUMO

By learning the optimal policy with a double deep Q-learning network (DDQN), we design ultra-broadband, biomimetic, perfect absorbers with various materials, based the structure of a moth's eye. All absorbers achieve over 90% average absorption from 400 to 1600 nm. By training a DDQN with moth-eye structures made up of chromium, we transfer the learned knowledge to other, similar materials to quickly and efficiently find the optimal parameters from the ∼1 billion possible options. The knowledge learned from previous optimisations helps the network to find the best solution for a new material in fewer steps, dramatically increasing the efficiency of finding designs with ultra-broadband absorption.

10.
Angew Chem Int Ed Engl ; 59(24): 9460-9469, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32237185

RESUMO

Interest and challenges remain in designing and synthesizing catalysts with nature-like complexity at few-nm scale to harness unprecedented functionalities by using sustainable solar light. We introduce "nanocatalosomes"-a bio-inspired bilayer-vesicular design of nanoreactor with metallic bilayer shell-in-shell structure, having numerous controllable confined cavities within few-nm interlayer space, customizable with different noble metals. The intershell-confined plasmonically coupled hot-nanospaces within the few-nm cavities play a pivotal role in harnessing catalytic effects for various organic transformations, as demonstrated by "acceptorless dehydrogenation", "Suzuki-Miyaura cross-coupling" and "alkynyl annulation" affording clean conversions and turnover frequencies (TOFs) at least one order of magnitude higher than state-of-the-art Au-nanorod-based plasmonic catalysts. This work paves the way towards next-generation nanoreactors for chemical transformations with solar energy.

11.
Molecules ; 24(4)2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30795539

RESUMO

Although melanin production is a key self-defense mechanism against ultraviolet radiation (UVR)-induced skin damage, uneven or excessive deposition of melanin causes hyperpigmentary disorders. Currently available whitening agents are unsatisfactory because of issues with efficacy and safety. To develop more effective depigmenting agents, we performed high-throughput melanin content assay screening using the B16F10 melanoma cell line and identified L-765,314 as a drug that suppressed melanin production in cultured melanocytes in a dose-dependent manner as well as cAMP- or 12-O-tetradecanoylphorbol 13-acetate (TPA)-stimulated melanin production without cytotoxicity. Interestingly, melanogenic gene expression was not altered by L-765,314. Rather, diminished melanin production by L-765,314 appeared to be caused by downregulation of tyrosinase activity via inhibition of protein kinase C (PKC). Because L-765,314 did not show any adverse effect in melanocytes, altogether our data suggest that L-765,314 could be a potential therapeutic candidate for skin hyperpigmentary disorders and further discovery of selective inhibitors targeting PKC might be a promising strategy for the development of depigmenting agents to treat hyperpigmentary disorders.


Assuntos
Clareadores/farmacologia , Inibidores Enzimáticos/farmacologia , Melaninas/antagonistas & inibidores , Monofenol Mono-Oxigenase/antagonistas & inibidores , Prazosina/análogos & derivados , Proteína Quinase C/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Clareadores/química , AMP Cíclico/farmacologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Regulação da Expressão Gênica , Ensaios de Triagem em Larga Escala , Melaninas/biossíntese , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Prazosina/química , Prazosina/farmacologia , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Transdução de Sinais , Bibliotecas de Moléculas Pequenas/química , Acetato de Tetradecanoilforbol/farmacologia , Células Tumorais Cultivadas
12.
Mol Carcinog ; 57(11): 1492-1506, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29964331

RESUMO

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been characterized as an anti-cancer therapeutic agent with prominent cancer cell selectivity over normal cells. However, breast cancer cells are generally resistant to TRAIL, thus limiting its therapeutic potential. In this study, we found that BIX-01294, a selective inhibitor of euchromatin histone methyltransferase 2/G9a, is a strong TRAIL sensitizer in breast cancer cells. The combination of BIX-01294 and TRAIL decreased cell viability and led to an increase in the annexin V/propidium iodide-positive cell population, DNA fragmentation, and caspase activation. BIX-01294 markedly increased death receptor 5 (DR5) expression, while silencing of DR5 using small interfering RNAs abolished the TRAIL-sensitizing effect of BIX-01294. Specifically, BIX-01294 induced C/EBP homologous protein (CHOP)-mediated DR5 gene transcriptional activation and DR5 promoter activation was induced by upregulation of the protein kinase R-like endoplasmic reticulum kinase-mediated activating transcription factor 4 (ATF4). Moreover, inhibition of reactive oxygen species by N-acetyl-L-cysteine efficiently blocked BIX-01294-induced DR5 upregulation by inhibiting ATF4/CHOP expression, leading to diminished sensitization to TRAIL. These findings suggest that BIX-01294 sensitizes breast cancer cells to TRAIL by upregulating ATF4/CHOP-dependent DR5 expression with a reactive oxygen species-dependent manner. Furthermore, combination treatment with BIX-01294 and TRAIL suppressed tumor growth and induced apoptosis in vivo. In conclusion, we found that epigenetic regulation can contribute to the development of resistance to cancer therapeutics such as TRAIL, and further studies of unfolded protein responses and the associated epigenetic regulatory mechanisms may lead to the discovery of new molecular targets for effective cancer therapy.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Neoplasias da Mama/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Antígenos de Histocompatibilidade/genética , Histona-Lisina N-Metiltransferase/genética , Espécies Reativas de Oxigênio/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Animais , Apoptose , Azepinas/farmacologia , Caspase 8/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Modelos Animais de Doenças , Feminino , Xenoenxertos , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Camundongos , Modelos Biológicos , Quinazolinas/farmacologia , Fator de Transcrição CHOP/metabolismo
13.
Opt Express ; 26(10): 13340-13348, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-29801359

RESUMO

It has been hard to achieve simultaneous plasmonic enhancement of nanoscale light-matter interactions in terms of both electric and magnetic manners with easily reproducible fabrication method and systematic theoretical design rule. In this paper, a novel concept of a flat nanofocusing device is proposed for simultaneously squeezing both electric and magnetic fields in deep-subwavelength volume (~λ3/538) in a large area. Based on the funneled unit cell structures and surface plasmon-assisted coherent interactions between them, the array of rectangular nanocavity connected to a tapered nanoantenna, plasmonic metasurface cavity, is constructed by periodic arrangement of the unit cell. The average enhancement factors of electric and magnetic field intensities reach about 60 and 22 in nanocavities, respectively. The proposed outstanding performance of the device is verified numerically and experimentally. We expect that this work would expand methodologies involving optical near-field manipulations in large areas and related potential applications including nanophotonic sensors, nonlinear responses, and quantum interactions.

14.
Calcif Tissue Int ; 101(6): 654-662, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28900676

RESUMO

As populations continue to age worldwide, sarcopenic obesity has heightened interest due to its medical importance. Although much evidence now indicates that n-3 fatty acids (FAs) may have beneficial effects on body composition including fat and muscle, their exact mechanisms have not yet been elucidated. Because free FA receptor 4 (FFA4) has been reported to be a receptor for n-3 FAs, we hypothesized that the protective role of n-3 FAs on body composition could be mediated by FFA4. To test this possibility, we generated mice overexpressing n-3 FAs but lacking FFA4 by crossing fat-1 transgenic (fat-1 Tg+) and FFA4 knockout (Ffar4 -/-) mice. Because fat-1 Tg+ mice, in which n-6 is endogenously converted into n-3 FAs, contain high n-3 FA levels, they could be a good animal model for studying the effects of n-3 FAs in vivo. Male and female littermates were included in high-fat-diet- (HFD) and ovariectomy-induced models, respectively. In the HFD model, male fat-1 Tg+ mice had a lower percentage of fat mass and a higher percentage of lean mass than their wild-type littermates only when they had the Ffar4 +/+ not the Ffar4 -/- background. Female fat-1 Tg+ mice showed less increase of fat mass percentage and less decrease of lean mass percentage after ovariectomy than wild-type littermates. However, these effects on body composition were attenuated in the Ffar4 -/- background. Taken together, our results indicate that the beneficial effects of n-3 FAs on body composition were mediated by FFA4 and thus suggest that FFA4 may be a potential therapeutic target for modulating sarcopenic obesity.


Assuntos
Composição Corporal/fisiologia , Ácidos Graxos Ômega-3/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Dieta Hiperlipídica , Feminino , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Ovariectomia
15.
Int J Mol Sci ; 18(6)2017 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-28608807

RESUMO

Immunomodulatory drugs (IMiDs) present one example of immunomodulatory agents that improve cancer immunotherapy. Based on the cytotoxic activity of natural killer (NK) cells against cancer cells, a high throughput screening method for the identification of novel immunomodulatory molecules with the potential to stimulate NK cell cytotoxicity against cancer cells was designed and tested using an approved drug library. Among the primary hit compounds, the anti-fungal drug amphotericin B (AMP-B) increased the cytotoxicity of NK cell line and human primary NK cells in a direct manner. The increase in NK cell activity was related to increased formation of NK-target cell conjugates and the subsequent granule polarization toward target cells. The results of the present study indicate that AMP-B could serve a dual function as an anti-fungal and immunomodulatory drug.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Fatores Imunológicos/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Grânulos Citoplasmáticos/efeitos dos fármacos , Grânulos Citoplasmáticos/imunologia , Humanos , Imunoterapia/métodos , Células Matadoras Naturais/imunologia , Neoplasias/imunologia , Neoplasias/terapia
16.
Biochem Biophys Res Commun ; 473(1): 336-341, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27018384

RESUMO

EFC-1 integrase is a site-specific recombinase that belongs to the large family of serine recombinase. In previously study, we isolated the temperate phage EFC-1, and characterized its genomic sequence. Within its genome, Orf28 was predicted encode a 464 amino acid of a putative integrase gene. In this study, EFC-1 integrase was characterized in vitro and in vivo. In vitro assay was performed using purified His-tag fusion integrase. Also, to identify which serine is involved in the catalytic domain, we used site-directed mutagenesis and analyzed by a recombination assay in vitro. In vivo assay involved PCR and confocal microscopy in HEK293 cells, and determined the minimal lengths of attP and attB sites. According to our results, the EFC-1 integrase-mediated recombination was site-specific and unidirectional system in vitro and in vivo. Serine 21 of EFC-1 integrase plays a major role in the catalytic domain, and minimal sizes of attB and attP was defined 48 and 54 bp. Our finding may help develop a useful tool for gene therapy and gene delivery system.


Assuntos
Bacteriófagos/enzimologia , Integrases/genética , Recombinação Genética , Sítios de Ligação Microbiológicos , Bacteriófagos/genética , Sequência de Bases , Domínio Catalítico , Linhagem Celular , Citometria de Fluxo , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos , Genoma , Células HEK293 , Humanos , Integrases/química , Microscopia Confocal , Microscopia de Fluorescência , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Plasmídeos/metabolismo , Reação em Cadeia da Polimerase , Serina/química
17.
Opt Lett ; 41(18): 4394-7, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27628406

RESUMO

As the diffraction limit is approached, device miniaturization to integrate more functionality per area becomes more and more challenging. Here we propose a strategy to increase the functionality-per-area by exploiting the modal properties of a waveguide system. With such an approach the design of a mode-multiplexed nanophotonic modulator relying on the mode-selective absorption of a patterned indium-tin-oxide (ITO) is proposed. Full-wave simulations of a device operating at the telecom wavelength of 1550 nm show that two modes can be independently modulated, while maintaining performances in line with conventional single-mode ITO modulators reported in the recent literature. The proposed design principles can pave the way to a class of mode-multiplexed compact photonic devices able to effectively multiply the functionality-per-area in integrated photonic systems.

18.
Bioorg Med Chem Lett ; 26(3): 1097-1101, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26631318

RESUMO

Gambogic acid (GA), a natural product with a xanthone structure, has a broad range of anti-proliferative effects on cancer cell lines. We evaluated GA for its cytotoxic effects on T98G glioblastoma cells. GA exhibited potent anti-proliferative activity and induced apoptosis in T98G glioblastoma cells in a dose-dependent manner. Incubation of cells with GA revealed apoptotic features including increased Bax and AIF expression, cytochrome c release, and cleavage of caspase-3, -8, -9, and PARP, while Bcl-2 expression was downregulated. Furthermore, GA induced reactive oxygen species (ROS) generation in T98G cells. Our results indicate that GA increases Bax- and AIF-associated apoptotic signaling in glioblastoma cells.


Assuntos
Antineoplásicos/química , Xantonas/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Regulação para Baixo/efeitos dos fármacos , Glioma/metabolismo , Glioma/patologia , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Xantonas/isolamento & purificação , Xantonas/farmacologia
19.
Biochem Biophys Res Commun ; 458(1): 34-9, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25619137

RESUMO

Previous studies showed that cereblon (CRBN) binds to various cellular target proteins, implying that CRBN regulates a wide range of cell responses. In this study, we found that deletion of the Crbn gene desensitized mouse embryonic fibroblast cells to various cell death-promoting stimuli, including endoplasmic reticulum stress inducers. Mechanistically, deletion of Crbn activates pathways involved in the unfolded protein response prior to ER stress induction. Loss of Crbn activated PKR-like ER kinase (PERK) with enhanced phosphorylation of eIF2α. Following ER stress induction, loss of Crbn delayed dephosphorylation of eIF2α, while reconstitution of Crbn reversed enhanced phosphorylation of PERK and eIF2α. Lastly, we found that activation of the PERK/eIF2α pathway following Crbn deletion is caused by activation of AMP-activated protein kinase (AMPK). We propose that CRBN plays a role in cellular stress signaling, including the unfolded protein response, by controlling the activity of AMPK.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Proteínas do Tecido Nervoso/genética , Resposta a Proteínas não Dobradas/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Isquemia Encefálica/genética , Isquemia Encefálica/patologia , Morte Celular/genética , Células Cultivadas , Estresse do Retículo Endoplasmático/genética , Ativação Enzimática , Fibroblastos/citologia , Fibroblastos/fisiologia , Masculino , Proteínas de Membrana/metabolismo , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Oxigênio/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , eIF-2 Quinase/metabolismo
20.
Amino Acids ; 47(2): 281-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25366491

RESUMO

Discovery of the cancer-specific peptidic ligands have been emphasized for active targeting drug delivery system and non-invasive imaging. For the discovery of useful and applicable peptidic ligands, in vivo peptide-displayed phage screening has been performed in this study using a xenograft mouse model as a mimic microenvironment to tumor. To seek human lung cancer-specific peptides, M13 phage library displaying 2.9 × 10(9) random peptides was intravenously injected into mouse model bearing A549-derived xenograft tumor through the tail vein. Then the phages emerged from a course of four rounds of biopanning in the xenograft tumor tissue. Novel peptides were categorized into four groups according to a sequence-homology phylogenicity, and in vivo tumor-targeting capacity of these peptides was validated by whole body imaging with Cy5.5-labeled phages in various cancer types. The result revealed that novel peptides accumulated only in adenocarcinoma lung cancer cell-derived xenograft tissue. For further confirmation of the specific targeting ability, in vitro cell-binding assay and immunohistochemistry in vivo tumor tissue were performed with a selected peptide. The peptide was found to bind intensely to lung cancer cells both in vitro and in vivo, which was efficiently compromised with unlabeled phages in an in vitro competition assay. In conclusion, the peptides specifically targeting human lung cancer were discovered in this study, which is warranted to provide substantive feasibilities for drug delivery and imaging in terms of a novel targeted therapeutics and diagnostics.


Assuntos
Antineoplásicos , Sistemas de Liberação de Medicamentos , Neoplasias Pulmonares/tratamento farmacológico , Biblioteca de Peptídeos , Microambiente Tumoral/efeitos dos fármacos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
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