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1.
Microvasc Res ; 155: 104698, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38801943

ABSTRACT

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.

2.
Opt Express ; 31(8): 12162-12174, 2023 Apr 10.
Article in English | MEDLINE | ID: mdl-37157381

ABSTRACT

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.

3.
Nucleic Acids Res ; 49(4): 2390-2399, 2021 02 26.
Article in English | MEDLINE | ID: mdl-33544854

ABSTRACT

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.


Subject(s)
Adenine , CRISPR-Cas Systems , Gene Editing , Histone Deacetylase Inhibitors/pharmacology , Depsipeptides/pharmacology , Doxycycline/pharmacology , Green Fluorescent Proteins/analysis , Green Fluorescent Proteins/genetics , HEK293 Cells , HeLa Cells , Humans , Luminescent Agents/analysis , Protein Biosynthesis , RNA/biosynthesis
4.
Opt Express ; 30(23): 42663-42677, 2022 Nov 07.
Article in English | MEDLINE | ID: mdl-36366716

ABSTRACT

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.

5.
Biochem Biophys Res Commun ; 539: 48-55, 2021 02 05.
Article in English | MEDLINE | ID: mdl-33421768

ABSTRACT

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.


Subject(s)
CRISPR-Associated Protein 9/metabolism , Embryo, Mammalian/metabolism , Endonucleases/metabolism , Gene Editing , Gene Targeting/methods , RNA, Guide, Kinetoplastida/metabolism , Animals , Cell Line , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , RNA, Guide, Kinetoplastida/genetics
6.
Sensors (Basel) ; 21(13)2021 Jun 26.
Article in English | MEDLINE | ID: mdl-34206760

ABSTRACT

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.

7.
Phys Chem Chem Phys ; 22(4): 2337-2342, 2020 Jan 28.
Article in English | MEDLINE | ID: mdl-31932814

ABSTRACT

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.

8.
Angew Chem Int Ed Engl ; 59(24): 9460-9469, 2020 Jun 08.
Article in English | MEDLINE | ID: mdl-32237185

ABSTRACT

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.

9.
Molecules ; 24(4)2019 Feb 21.
Article in English | MEDLINE | ID: mdl-30795539

ABSTRACT

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.


Subject(s)
Bleaching Agents/pharmacology , Enzyme Inhibitors/pharmacology , Melanins/antagonists & inhibitors , Monophenol Monooxygenase/antagonists & inhibitors , Prazosin/analogs & derivatives , Protein Kinase C/antagonists & inhibitors , Small Molecule Libraries/pharmacology , Animals , Bleaching Agents/chemistry , Cyclic AMP/pharmacology , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemistry , Gene Expression Regulation , High-Throughput Screening Assays , Melanins/biosynthesis , Melanoma, Experimental/genetics , Melanoma, Experimental/metabolism , Melanoma, Experimental/pathology , Mice , Monophenol Monooxygenase/genetics , Monophenol Monooxygenase/metabolism , Prazosin/chemistry , Prazosin/pharmacology , Protein Kinase C/genetics , Protein Kinase C/metabolism , Signal Transduction , Small Molecule Libraries/chemistry , Tetradecanoylphorbol Acetate/pharmacology , Tumor Cells, Cultured
10.
Mol Carcinog ; 57(11): 1492-1506, 2018 11.
Article in English | MEDLINE | ID: mdl-29964331

ABSTRACT

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.


Subject(s)
Activating Transcription Factor 4/metabolism , Breast Neoplasms/metabolism , CCAAT-Enhancer-Binding Proteins/metabolism , Histocompatibility Antigens/genetics , Histone-Lysine N-Methyltransferase/genetics , Reactive Oxygen Species/metabolism , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism , TNF-Related Apoptosis-Inducing Ligand/metabolism , Animals , Apoptosis , Azepines/pharmacology , Caspase 8/metabolism , Cell Line, Tumor , Cell Survival , Disease Models, Animal , Female , Heterografts , Histocompatibility Antigens/metabolism , Histone-Lysine N-Methyltransferase/metabolism , Humans , Mice , Models, Biological , Quinazolines/pharmacology , Transcription Factor CHOP/metabolism
11.
Opt Express ; 26(10): 13340-13348, 2018 May 14.
Article in English | MEDLINE | ID: mdl-29801359

ABSTRACT

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.

12.
Calcif Tissue Int ; 101(6): 654-662, 2017 12.
Article in English | MEDLINE | ID: mdl-28900676

ABSTRACT

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.


Subject(s)
Body Composition/physiology , Fatty Acids, Omega-3/metabolism , Receptors, G-Protein-Coupled/metabolism , Animals , Diet, High-Fat , Female , Male , Mice , Mice, Knockout , Mice, Transgenic , Ovariectomy
13.
Int J Mol Sci ; 18(6)2017 Jun 13.
Article in English | MEDLINE | ID: mdl-28608807

ABSTRACT

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.


Subject(s)
Amphotericin B/pharmacology , Antifungal Agents/pharmacology , Immunologic Factors/pharmacology , Killer Cells, Natural/drug effects , Cell Line , Cells, Cultured , Cytoplasmic Granules/drug effects , Cytoplasmic Granules/immunology , Humans , Immunotherapy/methods , Killer Cells, Natural/immunology , Neoplasms/immunology , Neoplasms/therapy
14.
Biochem Biophys Res Commun ; 473(1): 336-341, 2016 Apr 22.
Article in English | MEDLINE | ID: mdl-27018384

ABSTRACT

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.


Subject(s)
Bacteriophages/enzymology , Integrases/genetics , Recombination, Genetic , Attachment Sites, Microbiological , Bacteriophages/genetics , Base Sequence , Catalytic Domain , Cell Line , Flow Cytometry , Gene Transfer Techniques , Genetic Therapy , Genetic Vectors , Genome , HEK293 Cells , Humans , Integrases/chemistry , Microscopy, Confocal , Microscopy, Fluorescence , Molecular Sequence Data , Mutagenesis, Site-Directed , Mutation , Plasmids/metabolism , Polymerase Chain Reaction , Serine/chemistry
15.
Opt Lett ; 41(18): 4394-7, 2016 Sep 15.
Article in English | MEDLINE | ID: mdl-27628406

ABSTRACT

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.

16.
Bioorg Med Chem Lett ; 26(3): 1097-1101, 2016 Feb 01.
Article in English | MEDLINE | ID: mdl-26631318

ABSTRACT

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.


Subject(s)
Antineoplastic Agents/chemistry , Xanthones/chemistry , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Caspase 3/metabolism , Caspase 8/metabolism , Caspase 9/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cytochromes c/metabolism , Down-Regulation/drug effects , Glioma/metabolism , Glioma/pathology , Humans , Proto-Oncogene Proteins c-bcl-2/metabolism , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Xanthones/isolation & purification , Xanthones/pharmacology
17.
Biochem Biophys Res Commun ; 458(1): 34-9, 2015 Feb 27.
Article in English | MEDLINE | ID: mdl-25619137

ABSTRACT

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.


Subject(s)
Endoplasmic Reticulum Stress/physiology , Nerve Tissue Proteins/genetics , Unfolded Protein Response/genetics , AMP-Activated Protein Kinases/metabolism , Adaptor Proteins, Signal Transducing , Animals , Brain Ischemia/genetics , Brain Ischemia/pathology , Cell Death/genetics , Cells, Cultured , Endoplasmic Reticulum Stress/genetics , Enzyme Activation , Fibroblasts/cytology , Fibroblasts/physiology , Male , Membrane Proteins/metabolism , Mice, Knockout , Nerve Tissue Proteins/metabolism , Oxygen/metabolism , Protein Serine-Threonine Kinases/metabolism , eIF-2 Kinase/metabolism
18.
Amino Acids ; 47(2): 281-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25366491

ABSTRACT

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.


Subject(s)
Antineoplastic Agents , Drug Delivery Systems , Lung Neoplasms/drug therapy , Peptide Library , Tumor Microenvironment/drug effects , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Xenograft Model Antitumor Assays
19.
Biochem Biophys Res Commun ; 450(1): 673-8, 2014 Jul 18.
Article in English | MEDLINE | ID: mdl-24950402

ABSTRACT

Although first identified for their roles in protein synthesis, certain ribosomal proteins exert pleiotropic physiological functions in the cell. Ribosomal protein L19 is overexpressed in breast cancer cells by amplification and copy number variation. In this study, we examined the novel pro-apoptotic role of ribosomal protein L19 in the breast cancer cell line MCF7. Overexpression of RPL19 sensitized MCF7 cells to endoplasmic reticulum stress-induced cell death. RPL19 overexpression itself was not cytotoxic; however, cell death induction was enhanced when RPL19 overexpressing cells were incubated with endoplasmic reticulum stress-inducing agents, and this sensitizing effect was specific to MCF7 cells. Examination of the cell signaling pathways that mediate the unfolded protein response (UPR) revealed that overexpression of RPL19 induced pre-activation of the UPR, including phosphorylation of pERK-like ER kinase (PERK), phosphorylation of eukaryotic translation initiation factor 2 alpha (eIF2α), and activation of p38 MAPK-associated stress signaling. Our findings suggest that upregulation of RPL19 induces ER stress, resulting in increased sensitivity to ER stress and enhanced cell death in MCF7 breast cancer cells.


Subject(s)
Apoptosis , Breast Neoplasms/metabolism , Endoplasmic Reticulum/metabolism , Oxidative Stress , Ribosomal Proteins/metabolism , Breast Neoplasms/chemistry , Breast Neoplasms/pathology , Endoplasmic Reticulum/chemistry , Female , Humans , MCF-7 Cells , Protein Denaturation , Protein Folding , Ribosomal Proteins/chemistry , Up-Regulation
20.
Invest New Drugs ; 32(3): 389-99, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24173966

ABSTRACT

The MET proto-oncogene product, which is the receptor for hepatocyte growth factor (HGF), has been implicated in tumorigenesis and metastatic progression. Point mutations in MET lead to the aberrant activation of the receptor in many types of human malignancies, and the deregulated activity of MET has been correlated with tumor growth, invasion, and metastasis. MET has therefore attracted considerable attention as a potential target in anticancer therapy. Here, we report that a novel MET kinase inhibitor, NPS-1034, inhibits various constitutively active mutant forms of MET as well as HGF-activated wild-type MET. NPS-1034 inhibited the proliferation of cells expressing activated MET and promoted the regression of tumors formed from such cells in a mouse xenograft model through anti-angiogenic and pro-apoptotic actions. NPS-1034 also inhibited HGF-stimulated activation of MET signaling in the presence or absence of serum. Furthermore, when tested on 27 different MET variants, NPS-1034 inhibited 15 of the 17 MET variants that exhibited autophosphorylation with nanomolar potency; only the F1218I and M1149T variants were not inhibited by NPS-1034. Notably, NPS-1034 inhibited three MET variants that are resistant to the MET inhibitors SU11274, NVP-BVU972, and PHA665752. Together, these results suggest that NPS-1034 can be used as a potent therapeutic agent for human malignancies bearing MET point mutations or expressing activated MET.


Subject(s)
Antineoplastic Agents/pharmacology , Heterocyclic Compounds, 2-Ring/pharmacology , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-met/antagonists & inhibitors , Pyrazoles/pharmacology , Animals , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Hepatocyte Growth Factor/pharmacology , Heterocyclic Compounds, 2-Ring/therapeutic use , Humans , Mice, Mutant Strains , Mutation , Neoplasms/drug therapy , Neoplasms/pathology , Protein Kinase Inhibitors/therapeutic use , Proto-Oncogene Mas , Proto-Oncogene Proteins c-met/genetics , Proto-Oncogene Proteins c-met/metabolism , Pyrazoles/therapeutic use , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
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