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1.
Nanoscale Horiz ; 8(10): 1345-1365, 2023 Sep 26.
Article in English | MEDLINE | ID: mdl-37608742

ABSTRACT

The integration of two-dimensional (2D) van der Waals materials with nanostructures has triggered a wide spectrum of optical and optoelectronic applications. Photonic structures of conventional materials typically lack efficient reconfigurability or multifunctionality. Atomically thin 2D materials can thus generate new functionality and reconfigurability for a well-established library of photonic structures such as integrated waveguides, optical fibers, photonic crystals, and metasurfaces, to name a few. Meanwhile, the interaction between light and van der Waals materials can be drastically enhanced as well by leveraging micro-cavities or resonators with high optical confinement. The unique van der Waals surfaces of the 2D materials enable handiness in transfer and mixing with various prefabricated photonic templates with high degrees of freedom, functionalizing as the optical gain, modulation, sensing, or plasmonic media for diverse applications. Here, we review recent advances in synergizing 2D materials to nanophotonic structures for prototyping novel functionality or performance enhancements. Challenges in scalable 2D materials preparations and transfer, as well as emerging opportunities in integrating van der Waals building blocks beyond 2D materials are also discussed.

2.
IEEE Trans Pattern Anal Mach Intell ; 45(5): 6372-6385, 2023 May.
Article in English | MEDLINE | ID: mdl-36112555

ABSTRACT

Stereo confidence estimation aims to estimate the reliability of the estimated disparity by stereo matching. Different from the previous methods that exploit the limited input modality, we present a novel method that estimates confidence map of an initial disparity by making full use of tri-modal input, including matching cost, disparity, and color image through deep networks. The proposed network, termed as Locally Adaptive Fusion Networks (LAF-Net), learns locally-varying attention and scale maps to fuse the tri-modal confidence features. Moreover, we propose a knowledge distillation framework to learn more compact confidence estimation networks as student networks. By transferring the knowledge from LAF-Net as teacher networks, the student networks that solely take as input a disparity can achieve comparable performance. To transfer more informative knowledge, we also propose a module to learn the locally-varying temperature in a softmax function. We further extend this framework to a multiview scenario. Experimental results show that LAF-Net and its variations outperform the state-of-the-art stereo confidence methods on various benchmarks.

3.
Biochem Biophys Res Commun ; 635: 1-11, 2022 12 20.
Article in English | MEDLINE | ID: mdl-36252331

ABSTRACT

Primary cilia, antenna-like cellular sensor structures, are generated from the mother centriole in the G0/G1 cell-cycle phase under control by cellular signaling pathways involving Wnt, hedgehog, and platelet-derived growth factor. Although primary ciliary dynamics have been reported to be closely related to ciliopathy and tumorigenesis, the molecular basis for the role of primary cilia in human disease is lacking. To clarify how Wnt3a affects primary ciliogenesis in anticancer drug-resistant cells, we derived specific drug-resistant subcell lines from A549 human lung cancer cells using anticancer drugs doxorubicin, dasatinib, and paclitaxel (A549/Dox, A549/Das, and A549/Pac, respectively). The primary cilia-containing cell population and primary cilia length increased in the A549/Dox and A549/Pac subcell lines under increased MDR1 expression, when compared to those in the parental A549 cells. In the A549/Das subcell line, primary cilia length increased but the cell population was not affected. In addition, Wnt3a increased primary cilia-containing cell population and primary cilia length in A549/Dox, A549/Das, and A549/Pac cells, without change of cell growth. Abnormal shapes of primary cilia were frequently observed by anticancer drug resistance and Wnt3a stimulation. Taken together, our results indicate that anticancer drug resistance and Wnt3a affect primary ciliogenesis synergistically, suggesting a potential new strategy for overcoming anticancer drug resistance.


Subject(s)
Antineoplastic Agents , Lung Neoplasms , Humans , A549 Cells , Antineoplastic Agents/therapeutic use , Doxorubicin/therapeutic use , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Paclitaxel/therapeutic use , Cilia/metabolism , Wnt3A Protein/metabolism
4.
IEEE Trans Pattern Anal Mach Intell ; 44(9): 5293-5313, 2022 Sep.
Article in English | MEDLINE | ID: mdl-33798066

ABSTRACT

Stereo matching is one of the most popular techniques to estimate dense depth maps by finding the disparity between matching pixels on two, synchronized and rectified images. Alongside with the development of more accurate algorithms, the research community focused on finding good strategies to estimate the reliability, i.e., the confidence, of estimated disparity maps. This information proves to be a powerful cue to naively find wrong matches as well as to improve the overall effectiveness of a variety of stereo algorithms according to different strategies. In this paper, we review more than ten years of developments in the field of confidence estimation for stereo matching. We extensively discuss and evaluate existing confidence measures and their variants, from hand-crafted ones to the most recent, state-of-the-art learning based methods. We study the different behaviors of each measure when applied to a pool of different stereo algorithms and, for the first time in literature, when paired with a state-of-the-art deep stereo network. Our experiments, carried out on five different standard datasets, provide a comprehensive overview of the field, highlighting in particular both strengths and limitations of learning-based strategies.

5.
EMBO Rep ; 22(12): e51503, 2021 12 06.
Article in English | MEDLINE | ID: mdl-34585824

ABSTRACT

ß-Catenin is a multifunctional protein and participates in numerous processes required for embryonic development, cell proliferation, and homeostasis through various molecular interactions and signaling pathways. To date, however, there is no direct evidence that ß-catenin contributes to cytokinesis. Here, we identify a novel p-S60 epitope on ß-catenin generated by Plk1 kinase activity, which can be found at the actomyosin contractile ring of early telophase cells and at the midbody of late telophase cells. Depletion of ß-catenin leads to cytokinesis-defective phenotypes, which eventually result in apoptotic cell death. In addition, phosphorylation of ß-catenin Ser60 by Plk1 is essential for the recruitment of Ect2 to the midbody, activation of RhoA, and interaction between ß-catenin, Plk1, and Ect2. Time-lapse image analysis confirmed the importance of ß-catenin phospho-Ser60 in furrow ingression and the completion of cytokinesis. Taken together, we propose that phosphorylation of ß-catenin Ser60 by Plk1 in cooperation with Ect2 is essential for the completion of cytokinesis. These findings may provide fundamental knowledge for the research of cytokinesis failure-derived human diseases.


Subject(s)
Actomyosin , Cytokinesis , Actomyosin/metabolism , Cell Cycle Proteins/metabolism , HeLa Cells , Humans , Phosphorylation , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins/metabolism , Spindle Apparatus/metabolism , beta Catenin/metabolism , Polo-Like Kinase 1
6.
Int J Mol Sci ; 22(14)2021 Jul 15.
Article in English | MEDLINE | ID: mdl-34299191

ABSTRACT

Primary cilia are nonmotile cellular signal-sensing antenna-like structures composed of microtubule-based structures that distinguish them from motile cilia in structure and function. Primary ciliogenesis is regulated by various cellular signals, such as Wnt, hedgehog (Hh), and platelet-derived growth factor (PDGF). The abnormal regulation of ciliogenesis is closely related to developing various human diseases, including ciliopathies and cancer. This study identified a novel primary ciliogenesis factor Cullin 1 (CUL1), a core component of Skp1-Cullin-F-box (SCF) E3 ubiquitin ligase complex, which regulates the proteolysis of dishevelled 2 (Dvl2) through the ubiquitin-proteasome system. Through immunoprecipitation-tandem mass spectrometry analysis, 176 Dvl2 interacting candidates were identified, of which CUL1 is a novel Dvl2 modulator that induces Dvl2 ubiquitination-dependent degradation. Neddylation-dependent CUL1 activity at the centrosomes was essential for centrosomal Dvl2 degradation and primary ciliogenesis. Therefore, this study provides a new mechanism of Dvl2 degradation by CUL1, which ultimately leads to primary ciliogenesis, and suggest a novel target for primary cilia-related human diseases.


Subject(s)
Cilia/physiology , Cullin Proteins/metabolism , Dishevelled Proteins/metabolism , Proteasome Endopeptidase Complex/metabolism , SKP Cullin F-Box Protein Ligases/metabolism , Ubiquitin/metabolism , Cells, Cultured , Humans , Protein Binding , Proteolysis , Signal Transduction , Ubiquitination
7.
Genes Genomics ; 43(5): 567-575, 2021 05.
Article in English | MEDLINE | ID: mdl-33826094

ABSTRACT

BACKGROUND: Upregulation of human enhancer filamentation 1 (HEF1/NEDD9/Cas-L) and Polo-like kinase 1 (Plk1) is closely correlated with metastasis of human cancer. However, the mechanism by which the overexpression of HEF1 or Plk1 stimulates cancer metastasis and induces tumorigenesis remains enigmatic. In addition, the accumulation of HEF1 at the focal adhesion (FA) is known to be an essential event in cancer cell migration, but the mechanism of how HEF1 is targeted to the FA remains yet to be unveiled. OBJECTIVE: This study was performed to elucidate the FA docking mechanism of HEF1 and to determine its effect on tumorigenesis. METHODS: To confirm the effect of the kinase on HEF1 translocation, various expression-knockdown stable cell lines were generated using a lentivirus system, and the effect of the HEF1-Plk1 complex on tumorigenesis was confirmed using a xenograft mouse model. RESULTS: Here, we show that Wnt5a-dependent Plk1 binding to HEF1 is critically required for HEF1 translocation to the FA. We also confirmed that Plk1 and CK1δ activities essential for HEF1 translocation are induced by Wnt5a. Finally, we confirmed the induction of tumorigenesis by the HEF1-Plk1 complex in the xenograft mouse model. CONCLUSION: Our data collectively unveil the Wnt5a-CK1δ-HEF1-Plk1-FA remodeling pathway that governs HEF1 transportation to the FA to induce cell migration and tumorigenesis. This study sheds light on a mechanism underlying tumorigenesis and provides new strategies for anticancer therapy.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Carcinogenesis/metabolism , Cell Cycle Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Wnt-5a Protein/metabolism , Adaptor Proteins, Signal Transducing/genetics , Animals , Carcinogenesis/genetics , Cell Cycle Proteins/genetics , Cell Movement , HEK293 Cells , HeLa Cells , Humans , Male , Mice , Mice, Inbred BALB C , Protein Serine-Threonine Kinases/genetics , Proto-Oncogene Proteins/genetics , Wnt-5a Protein/genetics , Polo-Like Kinase 1
8.
Int J Mol Sci ; 21(13)2020 Jul 07.
Article in English | MEDLINE | ID: mdl-32645923

ABSTRACT

In the past, several microtubule targeting agents (MTAs) have been developed into successful anticancer drugs. However, the usage of these drugs has been limited by the acquisition of drug resistance in many cancers. Therefore, there is a constant demand for the development of new therapeutic drugs. Here we report the discovery of 5-5 (3-cchlorophenyl)-N-(3-pyridinyl)-2-furamide (CPPF), a novel microtubule targeting anticancer agent. Using both 2D and 3D culture systems, we showed that CPPF was able to suppress the proliferation of diverse cancer cell lines. In addition, CPPF was able to inhibit the growth of multidrug-resistant cell lines that are resistant to other MTAs, such as paclitaxel and colchicine. Our results showed that CPPF inhibited growth by depolymerizing microtubules leading to mitotic arrest and apoptosis. We also confirmed CPPF anticancer effects in vivo using both a mouse xenograft and a two-step skin cancer mouse model. Using established zebrafish models, we showed that CPPF has low toxicity in vivo. Overall, our study proves that CPPF has the potential to become a successful anticancer chemotherapeutic drug.


Subject(s)
Antineoplastic Agents/pharmacology , Cell Proliferation/drug effects , Microtubules/metabolism , Neoplasms/drug therapy , A549 Cells , Animals , Apoptosis/drug effects , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Colchicine/pharmacology , Drug Resistance, Multiple/drug effects , Drug Resistance, Neoplasm/drug effects , Drug Screening Assays, Antitumor/methods , HeLa Cells , Hep G2 Cells , Humans , Jurkat Cells , K562 Cells , MCF-7 Cells , Male , Mice , Mitosis/drug effects , Neoplasms/metabolism , PC-3 Cells , Paclitaxel/pharmacology , U937 Cells , Xenograft Model Antitumor Assays/methods , Zebrafish
9.
Cell Rep ; 30(5): 1447-1462.e5, 2020 02 04.
Article in English | MEDLINE | ID: mdl-32023461

ABSTRACT

Primary cilium is an antenna-like microtubule-based cellular sensing structure. Abnormal regulation of the dynamic assembly and disassembly cycle of primary cilia is closely related to ciliopathy and cancer. The Wnt signaling pathway plays a major role in embryonic development and tissue homeostasis, and defects in Wnt signaling are associated with a variety of human diseases, including cancer. In this study, we provide direct evidence of Wnt3a-induced primary ciliogenesis, which includes a continuous pathway showing that the stimulation of Wnt3a, a canonical Wnt ligand, promotes the generation of ß-catenin p-S47 epitope by CK1δ, and these events lead to the reorganization of centriolar satellites resulting in primary ciliogenesis. We have also confirmed the application of our findings in MCF-7/ADR cells, a multidrug-resistant tumor cell model. Thus, our data provide a Wnt3a-induced primary ciliogenesis pathway and may provide a clue on how to overcome multidrug resistance in cancer treatment.


Subject(s)
Centrioles/metabolism , Cilia/metabolism , Organogenesis , Wnt3A Protein/metabolism , beta Catenin/metabolism , Amino Acid Sequence , Animals , Casein Kinases/metabolism , Centrosome/metabolism , Drug Resistance, Multiple , Drug Resistance, Neoplasm , Epitopes/metabolism , HEK293 Cells , HeLa Cells , Humans , Ligands , MCF-7 Cells , Mice , Phosphorylation , Phosphoserine/metabolism , Wnt3A Protein/chemistry
10.
Sci Rep ; 10(1): 1245, 2020 01 27.
Article in English | MEDLINE | ID: mdl-31988303

ABSTRACT

Fenugreek (Trigonella foenum-graecum) is an annual herbaceous plant and a staple of traditional health remedies for metabolic conditions including high cholesterol and diabetes. While the mechanisms of the beneficial actions of fenugreek remain unknown, a role for intestinal microbiota in metabolic homeostasis is likely. To determine if fenugreek utilizes intestinal bacteria to offset the adverse effects of high fat diets, C57BL/6J mice were fed control/low fat (CD) or high fat (HFD) diets each supplemented with or without 2% (w/w) fenugreek for 16 weeks. The effects of fenugreek and HFD on gut microbiota were comprehensively mapped and then statistically assessed in relation to effects on metrics of body weight, hyperlipidemia, and glucose tolerance. 16S metagenomic analyses revealed robust and significant effects of fenugreek on gut microbiota, with alterations in both alpha and beta diversity as well as taxonomic redistribution under both CD and HFD conditions. As previously reported, fenugreek attenuated HFD-induced hyperlipidemia and stabilized glucose tolerance without affecting body weight. Finally, fenugreek specifically reversed the dysbiotic effects of HFD on numerous taxa in a manner tightly correlated with overall metabolic function. Collectively, these data reinforce the essential link between gut microbiota and metabolic syndrome and suggest that the preservation of healthy populations of gut microbiota participates in the beneficial properties of fenugreek in the context of modern Western-style diets.


Subject(s)
Diet, High-Fat/adverse effects , Gastrointestinal Microbiome/drug effects , Plant Extracts/pharmacology , Animals , Bacteria/genetics , Blood Glucose , Body Weight/drug effects , Dietary Supplements , Disease Models, Animal , Dyslipidemias/prevention & control , Glucose/metabolism , Glucose Intolerance/prevention & control , Hyperlipidemias/drug therapy , Male , Mice , Mice, Inbred C57BL , Obesity/drug therapy , Obesity/microbiology , Plant Extracts/metabolism , RNA, Ribosomal, 16S/genetics , Trigonella/metabolism
11.
J Microbiol Biotechnol ; 30(1): 31-37, 2020 Jan 28.
Article in English | MEDLINE | ID: mdl-31752054

ABSTRACT

We previously identified a new heparinase inhibitor fungal metabolite, named CRM646-A, which showed inhibition of heparinase and telomerase activities in an in vitro enzyme assay and antimetastatic activity in a cell-based assay. In this study, we elucidated the mechanism by which CRM646-A rapidly induced nucleus condensation, plasma membrane disruption and morphological changes by increasing intracellular Ca2+ levels. Furthermore, PD98059, a mitogen-activated protein kinase (MEK) inhibitor, inhibited CRM646-A-induced nucleus condensation through ERK1/2 activation in rat 3Y1 fibroblast cells. We identified CRM646-A as a Ca2+ ionophore-like agent with a distinctly different chemical structure from that of previously reported Ca2+ ionophores. These results indicate that CRM646-A has the potential to be used as a new and effective antimetastatic drug.


Subject(s)
Calcium/metabolism , Cell Nucleus/metabolism , Fibroblasts/drug effects , Hydroxybenzoates/pharmacology , Animals , Cell Line , Enzyme Activation , Enzyme Inhibitors/pharmacology , Fibroblasts/metabolism , Fungi/chemistry , Heparin Lyase/antagonists & inhibitors , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Rats , Signal Transduction
12.
Medicine (Baltimore) ; 98(15): e15084, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30985662

ABSTRACT

Sphenopalatine ganglion block (SPGB) is a technique developed in the 1990s for the management of head and neck pain patients. Recently, transnasal sphenopalatine ganglion block (TN-SPGB) has been widely used for these patients; however, no objective methods exist for validating the success of TN-SPGB. In this study, we measured the changes in facial temperature before and 30 minutes after TN-SPGB by using digital infrared thermal imaging (DITI) to validate its success.The medical records of patients, who underwent TN-SPGB and facial DITI between January 2016 and December 2017, were reviewed. TN-SPGB and facial DITI were performed 36 times in 32 patients. The changes in facial temperatures measured at the forehead (V1), maxillary area (V2), and mandibular area (V3) by using DITI before and 30 minutes after TN-SPGB were recorded and compared. The temperatures on the ipsilateral and contralateral sides of these areas were also compared. The comparison between pain relief group and pain maintenance group was analyzed.After TN-SPGB, the temperature decreased significantly on both sides of V1 (P = .0208, 0.0181). No significant differences were observed between the ipsilateral and contralateral sides (P > .05). There was no correlation between changes in temperature and changes in pain score in the pain regions after the procedure (P > .05).The temperature decreased significantly in V1 area at 30 minutes after TN-SPGB compared with the temperature before TN-SPGB. Based on these results, we propose using DITI to measure temperature changes as an objective method for verifying the success of TN-SPGB.


Subject(s)
Body Temperature , Sphenopalatine Ganglion Block , Face , Female , Humans , Infrared Rays , Male , Middle Aged , Pain/diagnosis , Pain/physiopathology , Pain Management , Retrospective Studies , Thermography , Treatment Outcome
13.
Biochim Biophys Acta Mol Basis Dis ; 1865(9): 2157-2167, 2019 09 01.
Article in English | MEDLINE | ID: mdl-31034991

ABSTRACT

Alzheimer's disease (AD) is the most common age-related neurodegenerative disease, while obesity is a major global public health problem associated with the metabolic disorder type 2 diabetes mellitus (T2DM). Chronic obesity and T2DM have been identified as invariant risk factors for dementia and late-onset AD, while their impacts on the occurrence and development of AD remain unclear. As shown in our previous study, the diabetic mutation (db, Leprdb/db) induces mixed or vascular dementia in mature to middle-aged APPΔNL/ΔNL x PS1P264L/P264L knock-in mice (db/AD). In the present study, the impacts of the db mutation on young AD mice at 10 weeks of age were evaluated. The db mutation not only conferred young AD mice with severe obesity, impaired glucose regulation and activated mammalian target of rapamycin (mTOR) signaling pathway in the mouse cortex, but lead to a surprising improvement in memory. At this young age, mice also had decreased cerebral Aß content, which we have not observed at older ages. This was unlikely to be related to altered Aß synthesis, as both ß- and γ-secretase were unchanged. The db mutation also reduced the cortical IL-1ß mRNA level and IBA1 protein level in young AD mice, with no significant effect on the activation of microglia and astrocytes. We conclude that the db mutation could transitorily improve the memory of young AD mice, a finding that may be partially explained by the relatively improved glucose homeostasis in the brains of db/AD mice compared to their counterpart AD mice, suggesting that glucose regulation could be a strategy for prevention and treatment of neurodegenerative diseases like AD.


Subject(s)
Alzheimer Disease/pathology , Diabetes Mellitus, Type 2/mortality , Memory , Receptors, Leptin/genetics , Aging , Alzheimer Disease/metabolism , Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Peptides/metabolism , Animals , Behavior, Animal , Brain/metabolism , Brain/pathology , Calcium-Binding Proteins/metabolism , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/pathology , Disease Models, Animal , Glial Fibrillary Acidic Protein/metabolism , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Microfilament Proteins/metabolism , Receptors, Leptin/metabolism , Signal Transduction , TOR Serine-Threonine Kinases/metabolism
14.
Nurse Educ Pract ; 34: 43-47, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30445293

ABSTRACT

The purpose of this study was to investigate the nursing competency and educational needs of nurses on clinical nursing practice in order to provide basic evidences for a developing nursing education program. Participants of this study were 211 nurses working at a general hospital in Seoul, Korea. The data were collected using self-report questionnaires on nursing competencies and educational needs. Collected data were analysed using an SPSS program for frequency, mean, standard deviation, t-test, ANOVA, and Scheffe's post-hoc comparison. The participants' nursing competency was significantly different based on their age, marital condition, level of education, current working department, and clinical experience. Among the subcategories of nursing competency, the ethical nursing competency was found to be the highest, whereas scientific nursing competency was shown the lowest competency. The order of top three educational needs of the participants was emergency nursing, intensive nursing care, and cardiopulmonary resuscitation in that order. To ensure the provision of nursing performances to healthcare service recipients grounded in a higher level of nursing competency, it is important to support nurses via evidence based effective clinical nursing education that is developed for the nurses' educational needs in relation to their clinical experiences.


Subject(s)
Clinical Competence/standards , Education, Nursing, Continuing/methods , Needs Assessment , Nurses/standards , Adult , Analysis of Variance , Clinical Competence/statistics & numerical data , Education, Nursing, Continuing/standards , Education, Nursing, Continuing/statistics & numerical data , Female , Humans , Male , Middle Aged , Nurses/psychology , Nurses/statistics & numerical data , Republic of Korea , Surveys and Questionnaires
15.
IEEE Trans Image Process ; 28(3): 1299-1313, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30371368

ABSTRACT

We present a deep architecture that estimates a stereo confidence, which is essential for improving the accuracy of stereo matching algorithms. In contrast to existing methods based on deep convolutional neural networks (CNNs) that rely on only one of the matching cost volume or estimated disparity map, our network estimates the stereo confidence by using the two heterogeneous inputs simultaneously. Specifically, the matching probability volume is first computed from the matching cost volume with residual networks and a pooling module in a manner that yields greater robustness. The confidence is then estimated through a unified deep network that combines confidence features extracted both from the matching probability volume and its corresponding disparity. In addition, our method extracts the confidence features of the disparity map by applying multiple convolutional filters with varying sizes to an input disparity map. To learn our networks in a semi-supervised manner, we propose a novel loss function that use confident points to compute the image reconstruction loss. To validate the effectiveness of our method in a disparity post-processing step, we employ three post-processing approaches; cost modulation, ground control points-based propagation, and aggregated ground control points-based propagation. Experimental results demonstrate that our method outperforms state-of-the-art confidence estimation methods on various benchmarks.

16.
J Biol Chem ; 293(3): 847-862, 2018 01 19.
Article in English | MEDLINE | ID: mdl-29191835

ABSTRACT

Elevated expression of human enhancer filamentation 1 (HEF1; also known as NEDD9 or Cas-L) is an essential stimulus for the metastatic process of various solid tumors. This process requires HEF1 localization to focal adhesions (FAs). Although the association of HEF1 with FAs is considered to play a role in cancer cell migration, the mechanism targeting HEF1 to FAs remains unclear. Moreover, up-regulation of Polo-like kinase 1 (Plk1) positively correlates with human cancer metastasis, yet how Plk1 deregulation promotes metastasis remains elusive. Here, we report that casein kinase 1δ (CK1δ) phosphorylates HEF1 at Ser-780 and Thr-804 and that these phosphorylation events promote a physical interaction between Plk1 and HEF1. We found that this interaction is critical for HEF1 translocation to FAs and for inducing migration of HeLa cells. Plk1-docking phosphoepitopes were mapped/confirmed in HEF1 by various methods, including X-ray crystallography, and mutated for functional analysis in HeLa cells. In summary, our results reveal the role of a phosphorylation-dependent HEF1-Plk1 complex in HEF1 translocation to FAs to induce cell migration. Our findings provide critical mechanistic insights into the HEF1-Plk1 complex-dependent localization of HEF1 to FAs underlying the metastatic process and may therefore contribute to the development of new cancer therapies.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Cell Cycle Proteins/metabolism , Focal Adhesions/metabolism , Phosphoproteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Adaptor Proteins, Signal Transducing/genetics , Cell Cycle Proteins/genetics , Cell Line , Cell Proliferation/genetics , Cell Proliferation/physiology , Focal Adhesions/genetics , HeLa Cells , Humans , Immunoblotting , Immunoprecipitation , Phosphoproteins/genetics , Phosphorylation/genetics , Phosphorylation/physiology , Protein Serine-Threonine Kinases/genetics , Proto-Oncogene Proteins/genetics , Polo-Like Kinase 1
17.
PLoS One ; 12(8): e0181500, 2017.
Article in English | MEDLINE | ID: mdl-28771483

ABSTRACT

High fat diet-induced obesity is associated with inflammatory and oxidative signaling in macrophages that likely participates in metabolic and physiologic impairment. One key factor that could drive pathologic changes in macrophages is the pro-inflammatory, pro-oxidant enzyme NADPH oxidase. However, NADPH oxidase is a pleiotropic enzyme with both pathologic and physiologic functions, ruling out indiscriminant NADPH oxidase inhibition as a viable therapy. To determine if targeted inhibition of monocyte/macrophage NADPH oxidase could mitigate obesity pathology, we generated mice that lack the NADPH oxidase catalytic subunit NOX2 in myeloid lineage cells. C57Bl/6 control (NOX2-FL) and myeloid-deficient NOX2 (mNOX2-KO) mice were given high fat diet for 16 weeks, and subject to comprehensive metabolic, behavioral, and biochemical analyses. Data show that mNOX2-KO mice had lower body weight, delayed adiposity, attenuated visceral inflammation, and decreased macrophage infiltration and cell injury in visceral adipose relative to control NOX2-FL mice. Moreover, the effects of high fat diet on glucose regulation and circulating lipids were attenuated in mNOX2-KO mice. Finally, memory was impaired and markers of brain injury increased in NOX2-FL, but not mNOX2-KO mice. Collectively, these data indicate that NOX2 signaling in macrophages participates in the pathogenesis of obesity, and reinforce a key role for macrophage inflammation in diet-induced metabolic and neurologic decline. Development of macrophage/immune-specific NOX-based therapies could thus potentially be used to preserve metabolic and neurologic function in the context of obesity.


Subject(s)
Cognition , Diet, High-Fat/adverse effects , Gene Deletion , Membrane Glycoproteins/deficiency , Membrane Glycoproteins/genetics , Myeloid Cells/metabolism , NADPH Oxidases/deficiency , NADPH Oxidases/genetics , Animals , Body Composition/genetics , Body Weight/genetics , Brain/physiology , Cell Lineage , Gene Knockout Techniques , Intra-Abdominal Fat/metabolism , Mice , NADPH Oxidase 2
18.
Mol Cells ; 40(6): 401-409, 2017 Jun 30.
Article in English | MEDLINE | ID: mdl-28614913

ABSTRACT

The primary cilium is a non-motile microtubule-based organelle that protrudes from the surface of most human cells and works as a cellular antenna to accept extracellular signals. Primary cilia assemble from the basal body during the resting stage (G0 phase) and simultaneously disassemble with cell cycle re-entry. Defective control of assembly or disassembly causes diverse human diseases including ciliopathy and cancer. To identify the effective compounds for studying primary cilium disassembly, we have screened 297 natural compounds and identified 18 and 17 primary cilium assembly and disassembly inhibitors, respectively. Among them, the application of KY-0120, identified as Brefeldin A, disturbed Dvl2-Plk1-mediated cilium disassembly via repression of the interaction of CK1ɛ-Dvl2 and the expression of Plk1 mRNA. Therefore, our study may suggest useful compounds for studying the cellular mechanism of primary cilium disassembly to prevent ciliopathy and cancer.


Subject(s)
Brefeldin A/pharmacology , Cell Cycle Proteins/antagonists & inhibitors , Cilia/drug effects , Dishevelled Proteins/antagonists & inhibitors , Protein Serine-Threonine Kinases/antagonists & inhibitors , Proto-Oncogene Proteins/antagonists & inhibitors , Cell Cycle , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line , Cilia/metabolism , Ciliopathies/prevention & control , Dishevelled Proteins/genetics , Dishevelled Proteins/metabolism , HEK293 Cells , Humans , Neoplasms/prevention & control , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , RNA, Messenger/antagonists & inhibitors , Small Molecule Libraries/pharmacology , Polo-Like Kinase 1
19.
PLoS One ; 12(4): e0175577, 2017.
Article in English | MEDLINE | ID: mdl-28441394

ABSTRACT

Maternal obesity is known to predispose offspring to metabolic and neurodevelopmental abnormalities. While the mechanisms underlying these phenomena are unclear, high fat diets dramatically alter intestinal microbiota, and gut microbiota can impact physiological function. To determine if maternal diet-induced gut dysbiosis can disrupt offspring neurobehavioral function, we transplanted high fat diet- (HFD) or control low fat diet-associated (CD) gut microbiota to conventionally-housed female mice. Recipient mice were then bred and the behavioral phenotype of male and female offspring was tracked. While maternal behavior was unaffected, neonatal offspring from HFD dams vocalized less upon maternal separation than pups from CD dams. Furthermore, weaned male offspring from HFD dams had significant and selective disruptions in exploratory, cognitive, and stereotypical/compulsive behavior compared to male offspring from CD dams; while female offspring from HFD dams had increases in body weight and adiposity. 16S metagenomic analyses confirmed establishment of divergent microbiota in CD and HFD dams, with alterations in diversity and taxonomic distribution throughout pregnancy and lactation. Likewise, significant alterations in gut microbial diversity and distribution were noted in offspring from HFD dams compared to CD dams, and in males compared to females. Regression analyses of behavioral performance against differentially represented taxa suggest that decreased representation of specific members of the Firmicutes phylum predict behavioral decline in male offspring. Collectively, these data establish that high fat diet-induced maternal dysbiosis is sufficient to disrupt behavioral function in murine offspring in a sex-specific manner. Thus these data reinforce the essential link between maternal diet and neurologic programming in offspring and suggest that intestinal dysbiosis could link unhealthy modern diets to the increased prevalence of neurodevelopmental and childhood disorders.


Subject(s)
Anxiety/etiology , Cognition , Compulsive Behavior/etiology , Gastrointestinal Microbiome , Obesity/microbiology , Prenatal Exposure Delayed Effects/etiology , Adiposity , Animal Communication , Animals , Animals, Newborn , Anxiety/microbiology , Compulsive Behavior/microbiology , Female , Male , Maternal Nutritional Physiological Phenomena , Mice, Inbred C57BL , Pregnancy , Prenatal Exposure Delayed Effects/microbiology
20.
PLoS One ; 12(3): e0173311, 2017.
Article in English | MEDLINE | ID: mdl-28296906

ABSTRACT

We have identified the small molecule STK899704 as a structurally novel tubulin inhibitor. STK899704 suppressed the proliferation of cancer cell lines from various origins with IC50 values ranging from 0.2 to 1.0 µM. STK899704 prevented the polymerization of purified tubulin in vitro and also depolymerized microtubule in cultured cells leading to mitotic arrest, associated with increased Cdc25C phosphorylation and the accumulation of both cyclin B1 and polo-like kinase 1 (Plk1), and apoptosis. Unlike many anticancer drugs such as Taxol and doxorubicin, STK899704 effectively displayed antiproliferative activity against multidrug-resistant cancer cell lines. The proposed binding mode of STK899704 is at the interface between αß-tubulin heterodimer overlapping with the colchicine-binding site. Our in vivo carcinogenesis model further showed that STK 899704 is potent in both the prevention and regression of tumors, remarkably reducing the number and volume of skin tumor by STK899704 treatment. Moreover, it was significant to note that the efficacy of STK899704 was surprisingly comparable to 5-fluorouracil, a widely used anticancer therapeutic. Thus, our results demonstrate the potential of STK899704 to be developed as an anticancer chemotherapeutic and an alternative candidate for existing therapies.


Subject(s)
Antineoplastic Agents/pharmacology , Benzofurans/pharmacology , Tubulin Modulators/pharmacology , Animals , Antineoplastic Agents/chemistry , Benzofurans/chemistry , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cyclin B1/metabolism , Humans , Mice , Phosphorylation , Polymerization/drug effects , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Spindle Apparatus/drug effects , Tubulin/metabolism , Tubulin Modulators/chemistry , cdc25 Phosphatases/metabolism , Polo-Like Kinase 1
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