Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 65
Filter
1.
Cell ; 185(11): 1974-1985.e12, 2022 05 26.
Article in English | MEDLINE | ID: mdl-35512704

ABSTRACT

Comprehensive sequencing of patient tumors reveals genomic mutations across tumor types that enable tumorigenesis and progression. A subset of oncogenic driver mutations results in neomorphic activity where the mutant protein mediates functions not engaged by the parental molecule. Here, we identify prevalent variant-enabled neomorph-protein-protein interactions (neoPPI) with a quantitative high-throughput differential screening (qHT-dS) platform. The coupling of highly sensitive BRET biosensors with miniaturized coexpression in an ultra-HTS format allows large-scale monitoring of the interactions of wild-type and mutant variant counterparts with a library of cancer-associated proteins in live cells. The screening of 17,792 interactions with 2,172,864 data points revealed a landscape of gain of interactions encompassing both oncogenic and tumor suppressor mutations. For example, the recurrent BRAF V600E lesion mediates KEAP1 neoPPI, rewiring a BRAFV600E/KEAP1 signaling axis and creating collateral vulnerability to NQO1 substrates, offering a combination therapeutic strategy. Thus, cancer genomic alterations can create neo-interactions, informing variant-directed therapeutic approaches for precision medicine.


Subject(s)
Neoplasms , Proto-Oncogene Proteins B-raf , Carcinogenesis , Humans , Kelch-Like ECH-Associated Protein 1/genetics , Kelch-Like ECH-Associated Protein 1/metabolism , Mutation , NF-E2-Related Factor 2/metabolism , Neoplasms/genetics , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins B-raf/metabolism
2.
Anal Chem ; 96(6): 2425-2434, 2024 02 13.
Article in English | MEDLINE | ID: mdl-38291775

ABSTRACT

A high-throughput, rapid, and highly sensitive surface-enhanced Raman spectroscopy (SERS) microarray for screening multiple mycotoxins has been developed on a three-dimensional silver nanoparticle porous silicon (3D AgNP-Psi) SERS substrate, which was easy to be engineered by electrochemical etching and magnetron sputtering technology. The etching current density, etching waveform, and target material for magnetron sputtering have been investigated to obtain an optimal 3D SERS substrate. The optimized 3D AgNP-Psi SERS substrate showed an enhancement factor of 2.3 × 107 at 400 mA/cm2 constant current density etching for 20 s and Ag target magnetron sputtering for 200 nm thickness on the surface of Psi. The simulation electric field distribution showed the near-field enhancement can reach 3× higher than that of AuNPs. A protein microarray has been designed to screen multiple mycotoxins by AuNP Raman tags and a competitive immunoassay protocol on the surface of the 3D SERS substrate. The SERS protein microarray displayed wide linear detection ranges of 0.001-100 ng/mL for ochratoxin A, 0.01-100 ng/mL for aflatoxin B1, 0.001-10 ng/mL for deoxynivalenol, along with pg/mL low limit of detection, good recovery rates, repeatability, and reproducibility. The 3D SERS protein microarray is easily engineered and has a great potential application in medicine, environment, and food industry fields.


Subject(s)
Metal Nanoparticles , Mycotoxins , Mycotoxins/analysis , Silicon/chemistry , Silver/chemistry , Metal Nanoparticles/chemistry , Gold/chemistry , Reproducibility of Results , Porosity , Spectrum Analysis, Raman/methods , Immunoassay/methods
3.
Molecules ; 28(5)2023 Mar 06.
Article in English | MEDLINE | ID: mdl-36903643

ABSTRACT

Due to the massive use and abuse of pesticides, practices which have led to serious threats to human health, the research community must develop on-site and rapid detection technology of pesticide residues to ensure food safety. Here, a paper-based fluorescent sensor, integrated with molecularly imprinted polymer (MIP) targeting glyphosate, was prepared by a surface-imprinting strategy. The MIP was synthesized by a catalyst-free imprinting polymerization technique and exhibited highly selective recognition capability for glyphosate. The MIP-coated paper sensor not only remained selective, but also displayed a limit of detection of 0.29 µmol and a linear detection range from 0.5 to 10 µmol. Moreover, the detection time only took about 5 min, which is beneficial for rapid detection of glyphosate in food samples. The detection accuracy of such paper sensor was good, with a spiked recovery rate of 92-117% in real samples. The fluorescent MIP-coated paper sensor not only has good specificity, which is helpful to reduce the food matrix interference and shorten the sample pretreatment time, but it also has the merits of high stability, low-cost and ease of operation and carrying, displaying great potential for application in the on-site and rapid detection of glyphosate for food safety.


Subject(s)
Molecular Imprinting , Pesticide Residues , Pesticides , Humans , Molecularly Imprinted Polymers , Polymers/chemistry , Pesticides/analysis , Molecular Imprinting/methods , Limit of Detection , Electrochemical Techniques/methods , Glyphosate
4.
Anal Chem ; 94(51): 17939-17946, 2022 12 27.
Article in English | MEDLINE | ID: mdl-36519631

ABSTRACT

We have demonstrated the proof-of-concept of a label-free fluorescence quantitative detection platform based on gold nanoparticle (AuNP) enhancement intrinsic fluorescence of protein on the silica photonic crystal microsphere (SPCM) array. The label-free one-step competitive fluorescence immunoassay protocol has been proposed on the surface of the SPCM. Aflatoxin B1 (AFB1) as a model molecule was detected by the newly established method. AFB1-bovine serum albumin and monoclonal antibodies (Abs) of anti-AFB1 have been immobilized on the surfaces of SPCMs and AuNPs, respectively. AuNPs remarkably enhanced the intrinsic fluorescence of artificial antigens on the surface of the SPCM at near UV excitation. The simulation of electric field distribution showed that the maximum value of the near-field enhancement |E/E0| of the SPCM with AuNPs could reach 20. The label-free fluorescence enhancement effect comes from the synergistic effects of photonic crystal effect and AuNP plasmon effect. Such a label-free fluorescence detection method can provide a linear detection range from 0.1 to 10 ng/mL with a limit of detection of 0.025 ng/mL and good specificity for AFB1. The recovery rates in the spiked cereal samples were measured in the range of 84.07 ± 5.71%-101.02 ± 5.13%, which were consistent with that of the traditional enzyme linked immunosorbent assay method. The label-free detection platform displays great application potential in biology, medicine, agriculture, food industry, chemical industry, energy source, and environmental protection.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , Microspheres , Gold/chemistry , Silicon Dioxide/chemistry , Metal Nanoparticles/chemistry , Enzyme-Linked Immunosorbent Assay , Aflatoxin B1/analysis , Limit of Detection
5.
Nucleic Acids Res ; 48(22): 12792-12803, 2020 12 16.
Article in English | MEDLINE | ID: mdl-33270890

ABSTRACT

Telomeres at the ends of eukaryotic chromosomes are essential for genome integrality and stability. In order to identify genes that sustain telomere maintenance independently of telomerase recruitment, we have exploited the phenotype of over-long telomeres in the cells that express Cdc13-Est2 fusion protein, and examined 195 strains, in which individual non-essential gene deletion causes telomere shortening. We have identified 24 genes whose deletion results in dramatic failure of Cdc13-Est2 function, including those encoding components of telomerase, Yku, KEOPS and NMD complexes, as well as quite a few whose functions are not obvious in telomerase activity regulation. We have characterized Swc4, a shared subunit of histone acetyltransferase NuA4 and chromatin remodeling SWR1 (SWR1-C) complexes, in telomere length regulation. Deletion of SWC4, but not other non-essential subunits of either NuA4 or SWR1-C, causes significant telomere shortening. Consistently, simultaneous disassembly of NuA4 and SWR1-C does not affect telomere length. Interestingly, inactivation of Swc4 in telomerase null cells accelerates both telomere shortening and senescence rates. Swc4 associates with telomeric DNA in vivo, suggesting a direct role of Swc4 at telomeres. Taken together, our work reveals a distinct role of Swc4 in telomere length regulation, separable from its canonical roles in both NuA4 and SWR1-C.


Subject(s)
Adenosine Triphosphatases/genetics , Histone Acetyltransferases/genetics , Saccharomyces cerevisiae Proteins/genetics , Telomere Homeostasis/genetics , Chromatin/genetics , DNA-Binding Proteins/genetics , Gene Expression Regulation, Fungal/genetics , Histones/genetics , Humans , Multiprotein Complexes/genetics , Saccharomyces cerevisiae/genetics , Telomerase/genetics , Telomere/genetics , Telomere-Binding Proteins/genetics
6.
Compr Rev Food Sci Food Saf ; 21(6): 4900-4920, 2022 11.
Article in English | MEDLINE | ID: mdl-36117270

ABSTRACT

Chemical contaminants in food generally include natural toxins (mycotoxins, animal toxins, and phytotoxins), pesticides, veterinary drugs, environmental pollutants, heavy metals, and illegal additives. Developing a low-cost, simple, and rapid detection technology for harmful substances in food is urgently needed. Analytical methods based on different advanced materials have been developed into rapid detection methods for food samples. In particular, photonic crystal (PC) materials have a unique surface periodic structure, structural color, a large surface area, easy integration with photoelectronic and magnetic devices which have great advantages in the development of rapid, low-cost, and highly sensitive analytical methods. This review focuses on the PC materials in the view of their fabrication processes, functionalized recognition components for the specific recognition of hazardous substances, and applications in the separation, enrichment, and detection of chemical hazards in real samples. Suspension array based on three-dimensional PC microspheres by droplet-based microfluidic assembly is a great promising and powerful platform for food safety detection fields. For the PCs selective analysis, biological antibodies, aptamers, and molecularly imprinted polymers (MIPs) could be modified for specific recognition of target substances, particularly MIPs because of their low-cost and easy mass production. Based on these functional PCs, various toxic and hazardous substances can be selectively enriched or recognized in real samples and further quantified in combination of liquid chromatography method or optical detection methods including fluorescence, chemiluminescence, and Raman spectroscopy.


Subject(s)
Molecular Imprinting , Mycotoxins , Animals , Molecular Imprinting/methods , Polymers/chemistry , Food Safety , Hazardous Substances
7.
J Biol Chem ; 293(17): 6434-6448, 2018 04 27.
Article in English | MEDLINE | ID: mdl-29540482

ABSTRACT

Fibroblast growth factor (FGF)/FGF receptor (FGFR) signaling facilitates tumor initiation and progression. Although currently approved inhibitors of FGFR kinase have shown therapeutic benefit in clinical trials, overexpression or mutations of FGFRs eventually confer drug resistance and thereby abrogate the desired activity of kinase inhibitors in many cancer types. In this study, we report that loss of myristoylation of fibroblast growth factor receptor substrate 2 (FRS2α), a scaffold protein essential for FGFR signaling, inhibits FGF/FGFR-mediated oncogenic signaling and FGF10-induced tumorigenesis. Moreover, a previously synthesized myristoyl-CoA analog, B13, which targets the activity of N-myristoyltransferases, suppressed FRS2α myristoylation and decreased the phosphorylation with mild alteration of FRS2α localization at the cell membrane. B13 inhibited oncogenic signaling induced by WT FGFRs or their drug-resistant mutants (FGFRsDRM). B13 alone or in combination with an FGFR inhibitor suppressed FGF-induced WT FGFR- or FGFRDRM-initiated phosphoinositide 3-kinase (PI3K) activity or MAPK signaling, inducing cell cycle arrest and thereby inhibiting cell proliferation and migration in several cancer cell types. Finally, B13 significantly inhibited the growth of xenograft tumors without pathological toxicity to the liver, kidney, or lung in vivo In summary, our study suggests a possible therapeutic approach for inhibiting FGF/FGFR-mediated cancer progression and drug-resistant FGF/FGFR mutants.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Amides/pharmacology , Fibroblast Growth Factors/metabolism , Lipoylation/drug effects , MAP Kinase Signaling System/drug effects , Membrane Proteins/metabolism , Neoplasm Proteins/metabolism , Neoplasms, Experimental/metabolism , Propanolamines/pharmacology , Prostatic Neoplasms/metabolism , Receptors, Fibroblast Growth Factor/metabolism , Adaptor Proteins, Signal Transducing/genetics , Animals , Cell Line, Tumor , Fibroblast Growth Factors/genetics , Humans , Male , Membrane Proteins/genetics , Mice , Mice, SCID , NIH 3T3 Cells , Neoplasm Proteins/drug effects , Neoplasm Proteins/genetics , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/genetics , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Prostatic Neoplasms/genetics , Receptors, Fibroblast Growth Factor/genetics
8.
J Biol Chem ; 293(27): 10547-10560, 2018 07 06.
Article in English | MEDLINE | ID: mdl-29773652

ABSTRACT

Interactions between cells in the stroma and epithelium facilitate prostate stem cell activity and tissue regeneration capacity. Numerous molecular signal transduction pathways, including the induction of sonic hedgehog (Shh) to activate the Gli transcription factors, are known to mediate the cross-talk of these two cellular compartments. However, the details of how these signaling pathways regulate prostate stem and progenitor cell activity remain elusive. Here we demonstrate that, although cell-autonomous epithelial Shh-Gli signaling is essential to determine the expression levels of basal cell markers and the renewal potential of epithelial stem and progenitor cells, stromal Gli signaling regulates prostate stem and progenitor cell activity by increasing the number and size of prostate spheroids in vitro Blockade of stromal Gli signaling also inhibited prostate tissue regeneration in vivo The inhibition of stromal Gli signaling suppressed the differentiation of basal and progenitor cells to luminal cells and limited prostate tubule secretory capability. Additionally, stromal cells were able to compensate for the deficiency of epithelial Shh signaling in prostate tissue regeneration. Mechanistically, suppression of Gli signaling increased the signaling factor transforming growth factor ß (TGFß) in stromal cells. Elevation of exogenous TGFß1 levels inhibited prostate spheroid formation, suggesting that a stromal Gli-TGFß signaling axis regulates the activity of epithelial progenitor cells. Our study illustrates that Gli signaling regulates epithelial stem cell activity and renewal potential in both epithelial and stromal compartments.


Subject(s)
Cell Differentiation , Prostate/cytology , Prostate/physiology , Stem Cells/cytology , Stem Cells/physiology , Stromal Cells/metabolism , Zinc Finger Protein GLI1/metabolism , Animals , Male , Mice , Mice, Inbred C57BL , Signal Transduction , Stromal Cells/cytology , Transforming Growth Factor beta/metabolism , Zinc Finger Protein GLI1/genetics
9.
J Biol Chem ; 293(9): 3410-3420, 2018 03 02.
Article in English | MEDLINE | ID: mdl-29321206

ABSTRACT

Short-chain acylation of lysine residues has recently emerged as a group of reversible posttranslational modifications in mammalian cells. The diversity of acylation further broadens the landscape and complexity of the proteome. Identification of regulatory enzymes and effector proteins for lysine acylation is critical to understand functions of these novel modifications at the molecular level. Here, we report that the MYST family of lysine acetyltransferases (KATs) possesses strong propionyltransferase activity both in vitro and in cellulo Particularly, the propionyltransferase activity of MOF, MOZ, and HBO1 is as strong as their acetyltransferase activity. Overexpression of MOF in human embryonic kidney 293T cells induced significantly increased propionylation in multiple histone and non-histone proteins, which shows that the function of MOF goes far beyond its canonical histone H4 lysine 16 acetylation. We also resolved the X-ray co-crystal structure of MOF bound with propionyl-coenzyme A, which provides a direct structural basis for the propionyltransferase activity of the MYST KATs. Our data together define a novel function for the MYST KATs as lysine propionyltransferases and suggest much broader physiological impacts for this family of enzymes.


Subject(s)
Histone Acetyltransferases/metabolism , Protein Processing, Post-Translational , Acetylation , Amino Acid Sequence , HEK293 Cells , Histone Acetyltransferases/chemistry , Humans , Lysine/metabolism , Models, Molecular , Protein Conformation , Proteomics
10.
Br J Cancer ; 121(12): 1039-1049, 2019 12.
Article in English | MEDLINE | ID: mdl-31690832

ABSTRACT

BACKGROUND: Tamoxifen resistance remains a significant clinical challenge for the therapy of ER-positive breast cancer. It has been reported that the upregulation of transcription factor SOX9 in ER+ recurrent cancer is sufficient for tamoxifen resistance. However, the mechanisms underlying the regulation of SOX9 remain largely unknown. METHODS: The acetylation level of SOX9 was detected by immunoprecipitation and western blotting. The expressions of HDACs and SIRTs were evaluated by qRT-PCR. Cell growth was measured by performing MTT assay. ALDH-positive breast cancer stem cells were evaluated by flow cytometry. Interaction between HDAC5 and SOX9 was determined by immunoprecipitation assay. RESULTS: Deacetylation is required for SOX9 nuclear translocation in tamoxifen-resistant breast cancer cells. Furthermore, HDAC5 is the key deacetylase responsible for SOX9 deacetylation and subsequent nuclear translocation. In addition, the transcription factor C-MYC directly promotes the expression of HDAC5 in tamoxifen resistant breast cancer cells. For clinical relevance, high SOX9 and HDAC5 expression are associated with lower survival rates in breast cancer patients treated with tamoxifen. CONCLUSIONS: This study reveals that HDAC5 regulated by C-MYC is essential for SOX9 deacetylation and nuclear localisation, which is critical for tamoxifen resistance. These results indicate a potential therapy strategy for ER+ breast cancer by targeting C-MYC/HDAC5/SOX9 axis.


Subject(s)
Breast Neoplasms/drug therapy , Histone Deacetylases/genetics , Proto-Oncogene Proteins c-myc/genetics , SOX9 Transcription Factor/genetics , Tamoxifen/pharmacology , Acetylation/drug effects , Aldehyde Dehydrogenase 1 Family/genetics , Breast/drug effects , Breast/metabolism , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Proliferation/drug effects , Drug Resistance, Neoplasm/drug effects , Estrogen Receptor alpha/genetics , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , MCF-7 Cells , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Receptors, Estrogen/genetics , Tamoxifen/adverse effects
11.
J Med Syst ; 43(9): 304, 2019 Aug 12.
Article in English | MEDLINE | ID: mdl-31407110

ABSTRACT

Due to insufficient samples, the generalization performance of deep network is insufficient. In order to solve this problem, an improved U-net based image automatic segmentation and diagnosis algorithm was proposed, in which the max-pooling operation in original U-net model was replaced by the convolution operation to keep more feature information. Firstly, the regions of 128×128 were extracted from all slices of the patients as data samples. Secondly, the patient samples were divided into training sample set and testing sample set, and data augmentation was performed on the training samples. Finally, all the training samples were adopted to train the model. Compared with Fully Convolutional Network (FCN) model and max-pooling based U-net model, DSC and CR coefficients of the proposed method achieve the best results, while PM coefficient is 2.55 percentage lower than the maximum value in the two comparison models, and Average Symmetric Surface Distance is slightly higher than the minimum value of the two comparison models by 0.004. The experimental results show that the proposed model can achieve good segmentation and diagnosis results.


Subject(s)
Diabetic Retinopathy/diagnosis , Image Processing, Computer-Assisted/methods , Neural Networks, Computer , Retina/diagnostic imaging , Algorithms , Humans , Sensitivity and Specificity
12.
J Biol Chem ; 292(45): 18422-18433, 2017 11 10.
Article in English | MEDLINE | ID: mdl-28939770

ABSTRACT

Exogenous fatty acids provide substrates for energy production and biogenesis of the cytoplasmic membrane, but they also enhance cellular signaling during cancer cell proliferation. However, it remains controversial whether dietary fatty acids are correlated with tumor progression. In this study, we demonstrate that increased Src kinase activity is associated with high-fat diet-accelerated progression of prostate tumors and that Src kinases mediate this pathological process. Moreover, in the in vivo prostate regeneration assay, host SCID mice carrying Src(Y529F)-transduced regeneration tissues were fed a low-fat diet or a high-fat diet and treated with vehicle or dasatinib. The high-fat diet not only accelerated Src-induced prostate tumorigenesis in mice but also compromised the inhibitory effect of the anticancer drug dasatinib on Src kinase oncogenic potential in vivo We further show that myristoylation of Src kinase is essential to facilitate Src-induced and high-fat diet-accelerated tumor progression. Mechanistically, metabolism of exogenous myristic acid increased the biosynthesis of myristoyl CoA and myristoylated Src and promoted Src kinase-mediated oncogenic signaling in human cells. Of the fatty acids tested, only exogenous myristic acid contributed to increased intracellular myristoyl CoA levels. Our results suggest that targeting Src kinase myristoylation, which is required for Src kinase association at the cellular membrane, blocks dietary fat-accelerated tumorigenesis in vivo Our findings uncover the molecular basis of how the metabolism of myristic acid stimulates high-fat diet-mediated prostate tumor progression.


Subject(s)
Antineoplastic Agents/therapeutic use , Diet, High-Fat/adverse effects , Prostate/drug effects , Prostatic Neoplasms/drug therapy , Protein Processing, Post-Translational/drug effects , Proto-Oncogene Proteins pp60(c-src)/metabolism , src-Family Kinases/antagonists & inhibitors , Acylation/drug effects , Amino Acid Substitution , Animals , Antineoplastic Agents/pharmacology , CSK Tyrosine-Protein Kinase , Cell Line, Tumor , Humans , Male , Mice, Inbred C57BL , Mice, SCID , Mutation , Myristic Acid/metabolism , Neoplasm Proteins/agonists , Neoplasm Proteins/antagonists & inhibitors , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Prostate/metabolism , Prostate/pathology , Prostatic Neoplasms/etiology , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Proto-Oncogene Proteins pp60(c-src)/chemistry , Proto-Oncogene Proteins pp60(c-src)/genetics , RNA Interference , Tumor Burden/drug effects , Xenograft Model Antitumor Assays , src-Family Kinases/genetics , src-Family Kinases/metabolism
13.
J Biol Chem ; 291(49): 25749-25760, 2016 Dec 02.
Article in English | MEDLINE | ID: mdl-27760825

ABSTRACT

Although the differentiation of oncogenically transformed basal progenitor cells is one of the key steps in prostate tumorigenesis, the mechanisms mediating this cellular process are still largely unknown. Here we demonstrate that an expanded p63+ and CK5+ basal/progenitor cell population, induced by the concomitant activation of oncogenic Kras(G12D) and androgen receptor (AR) signaling, underwent cell differentiation in vivo The differentiation process led to suppression of p63-expressing cells with a decreased number of CK5+ basal cells but an increase of CK8+ luminal tumorigenic cells and revealed a hierarchal lineage pattern consisting of p63+/CK5+ progenitor, CK5+/CK8+ transitional progenitor, and CK8+ differentiated luminal cells. Further analysis of the phenotype showed that Kras-AR axis-induced tumorigenesis was mediated by Gli transcription factors. Combined blocking of the activators of this family of proteins (Gli1 and Gli2) inhibited the proliferation of p63+ and CK5+ basal/progenitor cells and development of tumors. Finally, we identified that Gli1 and Gli2 exhibited different functions in the regulation of p63 expression or proliferation of p63+ cells in Kras-AR driven tumors. Gli2, but not Gli1, transcriptionally regulated the expression levels of p63 and prostate sphere formation. Our study provides evidence of a novel mechanism mediating pathological dysregulation of basal/progenitor cells through the differential activation of the Gli transcription factors. Also, these findings define Gli proteins as new downstream mediators of the Kras-AR axis in prostate carcinogenesis and open a potential therapeutic avenue of targeting prostate cancer progression by inhibiting Gli signaling.


Subject(s)
Cell Transformation, Neoplastic/metabolism , Kruppel-Like Transcription Factors/metabolism , Nuclear Proteins/metabolism , Prostate/metabolism , Prostatic Neoplasms/metabolism , Proto-Oncogene Proteins p21(ras)/metabolism , Receptors, Androgen/metabolism , Zinc Finger Protein GLI1/metabolism , Animals , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/pathology , Gene Expression Regulation, Neoplastic , Humans , Male , Mice , Mice, Transgenic , Phosphoproteins/genetics , Phosphoproteins/metabolism , Prostate/pathology , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Proto-Oncogene Proteins p21(ras)/genetics , Receptors, Androgen/genetics , Trans-Activators/genetics , Trans-Activators/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism , Zinc Finger Protein GLI1/genetics , Zinc Finger Protein Gli2
14.
Angew Chem Int Ed Engl ; 56(50): 15959-15963, 2017 12 11.
Article in English | MEDLINE | ID: mdl-28960837

ABSTRACT

In this study, an epitope-imprinting strategy was employed for the dynamic display of bioactive ligands on a material interface. An imprinted surface was initially designed to exhibit specific affinity towards a short peptide (i.e., the epitope). This surface was subsequently used to anchor an epitope-tagged cell-adhesive peptide ligand (RGD: Arg-Gly-Asp). Owing to reversible epitope-binding affinity, ligand presentation and thereby cell adhesion could be controlled. As compared to current strategies for the fabrication of dynamic biointerfaces, for example, through reversible covalent or host-guest interactions, such a molecularly tunable dynamic system based on a surface-imprinting process may unlock new applications in in situ cell biology, diagnostics, and regenerative medicine.


Subject(s)
Biocompatible Materials/chemistry , Epitopes/chemistry , Fibroblasts/chemistry , Molecular Imprinting , Oligopeptides/chemistry , 3T3 Cells , Animals , Cell Communication , Ligands , Mice , Molecular Structure , Surface Properties
15.
Nucleic Acids Res ; 42(6): 3607-22, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24423874

ABSTRACT

In prostate cancer, androgen receptor (AR) binding and androgen-responsive gene expression are defined by hormone-independent binding patterns of the pioneer factors FoxA1 and GATA2. Insufficient evidence of the mechanisms by which GATA2 contributes to this process precludes complete understanding of a key determinant of tissue-specific AR activity. Our observations suggest that GATA2 facilitates androgen-responsive gene expression by three distinct modes of action. By occupying novel binding sites within the AR gene locus, GATA2 positively regulates AR expression before and after androgen stimulation. Additionally, GATA2 engages AR target gene enhancers prior to hormone stimulation, producing an active and accessible chromatin environment via recruitment of the histone acetyltransferase p300. Finally, GATA2 functions in establishing and/or sustaining basal locus looping by recruiting the Mediator subunit MED1 in the absence of androgen. These mechanisms may contribute to the generally positive role of GATA2 in defining AR genome-wide binding patterns that determine androgen-responsive gene expression profiles. We also find that GATA2 and FoxA1 exhibit both independent and codependent co-occupancy of AR target gene enhancers. Identifying these determinants of AR transcriptional activity may provide a foundation for the development of future prostate cancer therapeutics that target pioneer factor function.


Subject(s)
GATA2 Transcription Factor/metabolism , Gene Expression Regulation, Neoplastic , Hepatocyte Nuclear Factor 3-alpha/metabolism , Prostatic Neoplasms/genetics , Receptors, Androgen/metabolism , Binding Sites , Cell Line, Tumor , Chromatin/chemistry , Chromatin/metabolism , Enhancer Elements, Genetic , Genome, Human , Humans , Male , Prostatic Neoplasms/metabolism , Receptors, Androgen/genetics
16.
Phys Chem Chem Phys ; 16(45): 24716-26, 2014 Dec 07.
Article in English | MEDLINE | ID: mdl-25315454

ABSTRACT

Atomic vacancies play an important role in the deformation and fracture processes of a metallic nanowire subjected to uniaxial tension. However, it is a great challenge to explore such evolution by experimental methods. Here, molecular dynamics simulations were used to study the deformation, fracture mechanism and mechanical character of gold nanowires with different atomic vacancies and sizes. Several valuable results were observed. Firstly, the statistical breaking position distributions showed two fracture styles of the gold nanowires. The small-sized gold nanowire exhibited a cluster rupture with disordered crystalline structures, and the breaking position appeared in the middle region, while the gold nanowire of large size exhibited an ordered slippage rupture and was apt to break at both ends. Secondly, the breaking position distribution of the large-sized gold nanowire was more sensitive to atomic vacancies than that of the small-sized gold nanowire. Thirdly, the mechanical strength could be improved by decreasing the gold nanowire size. Finally, small-sized gold nanowires had uncertain characteristics owing to the surface atom effects.

17.
Bioact Mater ; 38: 1-30, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38699243

ABSTRACT

Characterized by their pivotal roles in cell-to-cell communication, cell proliferation, and immune regulation during tissue repair, exosomes have emerged as a promising avenue for "cell-free therapy" in clinical applications. Hydrogels, possessing commendable biocompatibility, degradability, adjustability, and physical properties akin to biological tissues, have also found extensive utility in tissue engineering and regenerative repair. The synergistic combination of exosomes and hydrogels holds the potential not only to enhance the efficiency of exosomes but also to collaboratively advance the tissue repair process. This review has summarized the advancements made over the past decade in the research of hydrogel-exosome systems for regenerating various tissues including skin, bone, cartilage, nerves and tendons, with a focus on the methods for encapsulating and releasing exosomes within the hydrogels. It has also critically examined the gaps and limitations in current research, whilst proposed future directions and potential applications of this innovative approach.

18.
Food Chem ; 410: 135419, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-36623462

ABSTRACT

Development of multiple detection methods to monitor non-steroidal anti-inflammatory drugs (NSAIDs) in food is an effective way to protect human health. Here, we aimed to synthesize fluorescent artificial receptors by molecular imprinting technique to construct a simultaneous detection system targeting NSAIDs. Rhodamine B and fluorescein-functionalized silanes were employed as the fluorescence signal reporters for naproxen and ketoprofen, respectively. Two fluorescent molecularly imprinted polymers (FMIPs) were obtained with high specificity, giving cross-reactivity factors of 6.4-15.8 (naproxen) and 2.6-25.6 (ketoprofen). Both FMIPs also displayed rapid response time (5 min) and high sensitivity (detection limit at âˆ¼ nM level). A simultaneous detection system was constructed based on the FMIPs and applied for sensing the spiked NSAIDs in real samples, showing recoveries of 71-119 %, comparable with the HPLC methods (70-113 %). In summary, use of different FMIPs to construct simultaneous detection systems is practicable, and provides a flexible way for sensing multiple hazards in food samples.


Subject(s)
Ketoprofen , Molecular Imprinting , Receptors, Artificial , Humans , Naproxen , Anti-Inflammatory Agents, Non-Steroidal , Fluorescein , Coloring Agents , Molecular Imprinting/methods , Limit of Detection
19.
Anal Methods ; 15(43): 5803-5812, 2023 11 09.
Article in English | MEDLINE | ID: mdl-37901988

ABSTRACT

Fluorescent boronate affinity molecules have gained increasing attention in the field of fluorescence sensing and detection due to their selective recognition capability towards cis-diol-containing molecules (cis-diols). However, the conventional fluorescent boronate affinity molecules face a challenge in differentiating the type of cis-diol only by their fluorescence responses. In this study, a simple method was used to discriminate different types of cis-diols, including nucleosides, nucleotides, sugars, and glycoproteins based on the phenylboronic acid-functionalized fluorescent molecules combined with principal component analysis (PCA). Both fluorescent molecules were simply synthesized by the covalent interaction between the amino group in 3-aminophenyl boronic acid and the isothiocyanate group in fluorescein or rhodamine B. In view of their fluorescence-responsive behaviors to these cis-diols directly, it is impossible to differentiate their types even under the optimized experimental conditions. When PCA was employed to treat the fluorescence response data and the quenching constants with their molecular weight, different types of cis-diols can be distinguished successfully. As a result, by integrating the fluorescence response of the boronate affinity probes with PCA, it can greatly improve the specific recognition capability of the boronic acids, providing a simple and direct way to distinguish and identify different types of cis-diols.


Subject(s)
Nucleosides , Nucleotides , Principal Component Analysis , Glycoproteins
20.
J Chromatogr A ; 1695: 463932, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-36972663

ABSTRACT

Development of selective enrichment materials for the accurate analysis of ochratoxin a (OTA) in environmental and food samples is an effective way to protect human health. Here, a molecularly imprinted polymer (MIP) known as plastic antibody was synthesized onto the magnetic inverse opal photonic crystal microsphere (MIPCM) using a low-cost dummy template imprinting strategy targeting OTA. The MIP@MIPCM exhibited ultrahigh selectivity with an imprinting factor of 130, high specificity with cross-reactivity factors of 3.3-10.5, and large adsorption capacity of 60.5 µg/mg. Such MIP@MIPCM was used for selective capture of OTA in real samples which was quantified in combination with high-performance liquid chromatography, giving a wide linear detection range of 5-20,000 ng/mL, a detection limit of 0.675 ng/mL, and good recovery rates of 84-116%. Moreover, the MIP@MIPCM can be produced simply and rapidly and is very stable under different environmental conditions and easy to store and transport, so it is an ideal substitute of biological antibody modified materials for the selective enrichment of OTA in real samples.


Subject(s)
Molecular Imprinting , Molecularly Imprinted Polymers , Humans , Molecular Imprinting/methods , Microspheres , Polymers/chemistry , Chromatography, High Pressure Liquid , Adsorption , Magnetic Phenomena
SELECTION OF CITATIONS
SEARCH DETAIL