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1.
Cell ; 175(4): 1045-1058.e16, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30388443

ABSTRACT

Protein N-glycosylation is a widespread post-translational modification. The first committed step in this process is catalysed by dolichyl-phosphate N-acetylglucosamine-phosphotransferase DPAGT1 (GPT/E.C. 2.7.8.15). Missense DPAGT1 variants cause congenital myasthenic syndrome and disorders of glycosylation. In addition, naturally-occurring bactericidal nucleoside analogues such as tunicamycin are toxic to eukaryotes due to DPAGT1 inhibition, preventing their clinical use. Our structures of DPAGT1 with the substrate UDP-GlcNAc and tunicamycin reveal substrate binding modes, suggest a mechanism of catalysis, provide an understanding of how mutations modulate activity (thus causing disease) and allow design of non-toxic "lipid-altered" tunicamycins. The structure-tuned activity of these analogues against several bacterial targets allowed the design of potent antibiotics for Mycobacterium tuberculosis, enabling treatment in vitro, in cellulo and in vivo, providing a promising new class of antimicrobial drug.


Subject(s)
Antibiotics, Antitubercular/pharmacology , Congenital Disorders of Glycosylation/metabolism , Enzyme Inhibitors/pharmacology , N-Acetylglucosaminyltransferases/chemistry , Animals , Antibiotics, Antitubercular/chemistry , Binding Sites , Congenital Disorders of Glycosylation/genetics , Enzyme Inhibitors/chemistry , Female , HEK293 Cells , Hep G2 Cells , Humans , Lipid Metabolism , Mice , Molecular Docking Simulation , Mutation , N-Acetylglucosaminyltransferases/antagonists & inhibitors , N-Acetylglucosaminyltransferases/genetics , N-Acetylglucosaminyltransferases/metabolism , Protein Binding , Sf9 Cells , Spodoptera , Tunicamycin/chemistry , Tunicamycin/pharmacology , Uridine Diphosphate Glucuronic Acid/chemistry , Uridine Diphosphate Glucuronic Acid/metabolism
2.
Nat Immunol ; 21(10): 1219-1231, 2020 10.
Article in English | MEDLINE | ID: mdl-32778760

ABSTRACT

Chronic inflammation is a common feature of obesity, with elevated cytokines such as interleukin-1 (IL-1) in the circulation and tissues. Here, we report an unconventional IL-1R-MyD88-IRAK2-PHB/OPA1 signaling axis that reprograms mitochondrial metabolism in adipocytes to exacerbate obesity. IL-1 induced recruitment of IRAK2 Myddosome to mitochondria outer membranes via recognition by TOM20, followed by TIMM50-guided translocation of IRAK2 into mitochondria inner membranes, to suppress oxidative phosphorylation and fatty acid oxidation, thereby attenuating energy expenditure. Adipocyte-specific MyD88 or IRAK2 deficiency reduced high-fat-diet-induced weight gain, increased energy expenditure and ameliorated insulin resistance, associated with a smaller adipocyte size and increased cristae formation. IRAK2 kinase inactivation also reduced high-fat diet-induced metabolic diseases. Mechanistically, IRAK2 suppressed respiratory super-complex formation via interaction with PHB1 and OPA1 upon stimulation of IL-1. Taken together, our results suggest that the IRAK2 Myddosome functions as a critical link between inflammation and metabolism, representing a novel therapeutic target for patients with obesity.


Subject(s)
Adipocytes/immunology , Inflammation/immunology , Interleukin-1 Receptor-Associated Kinases/metabolism , Interleukin-1/metabolism , Mitochondrial Membranes/metabolism , Obesity/immunology , Adipocytes/pathology , Animals , Cells, Cultured , Humans , Interleukin-1 Receptor-Associated Kinases/genetics , Male , Mice , Mice, Knockout , Myeloid Differentiation Factor 88/genetics , Myeloid Differentiation Factor 88/metabolism , Oxidative Phosphorylation , Prohibitins , Protein Transport , Receptors, Interleukin-1/metabolism , Signal Transduction
3.
Mol Cell ; 83(8): 1280-1297.e11, 2023 04 20.
Article in English | MEDLINE | ID: mdl-36924766

ABSTRACT

RNA polymerase II (RNA Pol II) has been recognized as a passively regulated multi-subunit holoenzyme. However, the extent to which RNA Pol II subunits might be important beyond the RNA Pol II complex remains unclear. Here, fractions containing disassociated RPB3 (dRPB3) were identified by size exclusion chromatography in various cells. Through a unique strategy, i.e., "specific degradation of disassociated subunits (SDDS)," we demonstrated that dRPB3 functions as a regulatory component of RNA Pol II to enable the preferential control of 3' end processing of ribosomal protein genes directly through its N-terminal domain. Machine learning analysis of large-scale genomic features revealed that the little elongation complex (LEC) helps to specialize the functions of dRPB3. Mechanistically, dRPB3 facilitates CBC-PCF11 axis activity to increase the efficiency of 3' end processing. Furthermore, RPB3 is dynamically regulated during development and diseases. These findings suggest that RNA Pol II gains specific regulatory functions by trapping disassociated subunits in mammalian cells.


Subject(s)
RNA Polymerase II , Transcription, Genetic , Animals , RNA Polymerase II/metabolism , Ribosomal Proteins/genetics , Ribosomal Proteins/metabolism , Ribosomes/metabolism , Protein Subunits/genetics , Mammals/metabolism
4.
EMBO J ; 42(4): e111883, 2023 02 15.
Article in English | MEDLINE | ID: mdl-36546550

ABSTRACT

Proper stamen filament elongation is essential for pollination and plant reproduction. Plant hormones are extensively involved in every stage of stamen development; however, the cellular mechanisms by which phytohormone signals couple with microtubule dynamics to control filament elongation remain unclear. Here, we screened a series of Arabidopsis thaliana mutants showing different microtubule defects and revealed that only those unable to sever microtubules, lue1 and ktn80.1234, displayed differential floral organ elongation with less elongated stamen filaments. Prompted by short stamen filaments and severe decrease in KTN1 and KTN80s expression in qui-2 lacking five BZR1-family transcription factors (BFTFs), we investigated the crosstalk between microtubule severing and brassinosteroid (BR) signaling. The BFTFs transcriptionally activate katanin-encoding genes, and the microtubule-severing frequency was severely reduced in qui-2. Taken together, our findings reveal how BRs can regulate cytoskeletal dynamics to coordinate the proper development of reproductive organs.


Subject(s)
Brassinosteroids , Katanin , Microtubules , Arabidopsis/metabolism , Arabidopsis Proteins/metabolism , Brassinosteroids/metabolism , Katanin/genetics , Katanin/metabolism , Microtubules/metabolism , Plant Growth Regulators/metabolism
5.
PLoS Biol ; 22(8): e3002763, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39133741

ABSTRACT

Phenotypic plasticity displayed by an animal in response to different environmental conditions is supposedly crucial for its survival and reproduction. The female adults of some ant lineages display phenotypic plasticity related to reproductive role. In pharaoh ant queens, insemination induces substantial physiological/behavioral changes and implicates remarkable gene regulatory network (GRN) shift in the brain. Here, we report a neuropeptide neuroparsin A (NPA) showing a conserved expression pattern associated with reproductive activity across ant species. Knock-down of NPA in unmated queen enhances ovary activity, whereas injection of NPA peptide in fertilized queen suppresses ovary activity. We found that NPA mainly affected the downstream gene JHBP in the ovary, which is positively regulated by NPA and suppression of which induces elevated ovary activity, and shadow which is negatively regulated by NPA. Furthermore, we show that NPA was also employed into the brain-ovary axis in regulating the worker reproductive changes in other distantly related species, such as Harpegnathos venator ants.


Subject(s)
Ants , Neuropeptides , Reproduction , Animals , Ants/physiology , Ants/genetics , Ants/metabolism , Reproduction/physiology , Female , Neuropeptides/metabolism , Neuropeptides/genetics , Insect Proteins/metabolism , Insect Proteins/genetics , Ovary/metabolism , Ovary/physiology , Brain/metabolism , Brain/physiology , Biological Evolution , Gene Regulatory Networks
6.
Proc Natl Acad Sci U S A ; 120(20): e2300860120, 2023 May 16.
Article in English | MEDLINE | ID: mdl-37155855

ABSTRACT

Photonic gauge potentials, including scalar and vector ones, play fundamental roles in emulating photonic topological effects and for enabling intriguing light transport dynamics. While previous studies mainly focus on manipulating light propagation in uniformly distributed gauge potentials, here we create a series of gauge-potential interfaces with different orientations in a nonuniform discrete-time quantum walk and demonstrate various reconfigurable temporal-refraction effects. We show that for a lattice-site interface with the potential step along the lattice direction, the scalar potentials can yield total internal reflection (TIR) or Klein tunneling, while vector potentials manifest direction-invariant refractions. We also reveal the existence of penetration depth for the temporal TIR by demonstrating frustrated TIR with a double lattice-site interface structure. By contrast, for an interface emerging in the time-evolution direction, the scalar potentials have no effect on the packet propagation, while the vector potentials can enable birefringence, through which we further create a "temporal superlens" to achieve time-reversal operations. Finally, we experimentally demonstrate electric and magnetic Aharonov-Bohm effects using combined lattice-site and evolution-step interfaces of either scalar or vector potential. Our work initiates the creation of artificial heterointerfaces in synthetic time dimension by employing nonuniformly and reconfigurable distributed gauge potentials. This paradigm may find applications in optical pulse reshaping, fiber-optic communications, and quantum simulations.

7.
PLoS Genet ; 19(3): e1010401, 2023 03.
Article in English | MEDLINE | ID: mdl-36989278

ABSTRACT

Genetic variation in mitochondrial and nuclear genomes can perturb mitonuclear interactions and lead to phenotypic differences between individuals and populations. Despite their importance to most complex traits, it has been difficult to identify the interacting mitonuclear loci. Here, we present a novel advanced intercrossed population of Saccharomyces cerevisiae yeasts, called the Mitonuclear Recombinant Collection (MNRC), designed explicitly for detecting mitonuclear loci contributing to complex traits. For validation, we focused on mapping genes that contribute to the spontaneous loss of mitochondrial DNA (mtDNA) that leads to the petite phenotype in yeast. We found that rates of petite formation in natural populations are variable and influenced by genetic variation in nuclear DNA, mtDNA and mitonuclear interactions. We mapped nuclear and mitonuclear alleles contributing to mtDNA stability using the MNRC by integrating a term for mitonuclear epistasis into a genome-wide association model. We found that the associated mitonuclear loci play roles in mitotic growth most likely responding to retrograde signals from mitochondria, while the associated nuclear loci with main effects are involved in genome replication. We observed a positive correlation between growth rates and petite frequencies, suggesting a fitness tradeoff between mitotic growth and mtDNA stability. We also found that mtDNA stability was correlated with a mobile mitochondrial GC-cluster that is present in certain populations of yeast and that selection for nuclear alleles that stabilize mtDNA may be rapidly occurring. The MNRC provides a powerful tool for identifying mitonuclear interacting loci that will help us to better understand genotype-phenotype relationships and coevolutionary trajectories.


Subject(s)
Epistasis, Genetic , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genetics , Genome-Wide Association Study , DNA, Mitochondrial/genetics , Mitochondria/genetics
8.
Nucleic Acids Res ; 51(21): 11634-11651, 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-37870468

ABSTRACT

Bromodomain-containing protein 9 (BRD9) is a specific subunit of the non-canonical SWI/SNF (ncBAF) chromatin-remodeling complex, whose function in human embryonic stem cells (hESCs) remains unclear. Here, we demonstrate that impaired BRD9 function reduces the self-renewal capacity of hESCs and alters their differentiation potential. Specifically, BRD9 depletion inhibits meso-endoderm differentiation while promoting neural ectoderm differentiation. Notably, supplementation of NODAL, TGF-ß, Activin A or WNT3A rescues the differentiation defects caused by BRD9 loss. Mechanistically, BRD9 forms a complex with BRD4, SMAD2/3, ß-CATENIN and P300, which regulates the expression of pluripotency genes and the activity of TGF-ß/Nodal/Activin and Wnt signaling pathways. This is achieved by regulating the deposition of H3K27ac on associated genes, thus maintaining and directing hESC differentiation. BRD9-mediated regulation of the TGF-ß/Activin/Nodal pathway is also demonstrated in the development of pancreatic and breast cancer cells. In summary, our study highlights the crucial role of BRD9 in the regulation of hESC self-renewal and differentiation, as well as its participation in the progression of pancreatic and breast cancers.


Subject(s)
Human Embryonic Stem Cells , Neoplasms , Humans , Transforming Growth Factor beta/genetics , Human Embryonic Stem Cells/metabolism , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Embryonic Stem Cells/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Cell Differentiation/genetics , Activins/metabolism , Wnt Signaling Pathway , Neoplasms/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism
9.
Nano Lett ; 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38593087

ABSTRACT

Flatband localization endowed with robustness holds great promise for disorder-immune light transport, particularly in the advancement of optical communication and signal processing. However, effectively harnessing these principles for practical applications in nanophotonic devices remains a significant challenge. Herein, we delve into the investigation of on-chip photonic localization in AB cages composed of indirectly coupled microring lattices. By strategically vertically shifting the auxiliary rings, we successfully introduce a magnetic flux of π into the microring lattice, thereby facilitating versatile control over the localization and delocalization of light. Remarkably, the compact edge modes of this structure exhibit intriguing topological properties, rendering them strongly robust against disorders, regardless of the size of the system. Our findings open up new avenues for exploring the interaction between flatbands and topological photonics on integrated platforms.

10.
Gut ; 73(7): 1110-1123, 2024 06 06.
Article in English | MEDLINE | ID: mdl-38378253

ABSTRACT

OBJECTIVE: Intestinal fibrosis is considered an inevitable consequence of chronic IBD, leading to stricture formation and need for surgery. During the process of fibrogenesis, extracellular matrix (ECM) components critically regulate the function of mesenchymal cells. We characterised the composition and function of ECM in fibrostenosing Crohn's disease (CD) and control tissues. DESIGN: Decellularised full-thickness intestinal tissue platforms were tested using three different protocols, and ECM composition in different tissue phenotypes was explored by proteomics and validated by quantitative PCR (qPCR) and immunohistochemistry. Primary human intestinal myofibroblasts (HIMFs) treated with milk fat globule-epidermal growth factor 8 (MFGE8) were evaluated regarding the mechanism of their antifibrotic response, and the action of MFGE8 was tested in two experimental intestinal fibrosis models. RESULTS: We established and validated an optimal decellularisation protocol for intestinal IBD tissues. Matrisome analysis revealed elevated MFGE8 expression in CD strictured (CDs) tissue, which was confirmed at the mRNA and protein levels. Treatment with MFGE8 inhibited ECM production in normal control HIMF but not CDs HIMF. Next-generation sequencing uncovered functionally relevant integrin-mediated signalling pathways, and blockade of integrin αvß5 and focal adhesion kinase rendered HIMF non-responsive to MFGE8. MFGE8 prevented and reversed experimental intestinal fibrosis in vitro and in vivo. CONCLUSION: MFGE8 displays antifibrotic effects, and its administration may represent a future approach for prevention of IBD-induced intestinal strictures.


Subject(s)
Antigens, Surface , Crohn Disease , Extracellular Matrix , Fibrosis , Milk Proteins , Humans , Animals , Crohn Disease/pathology , Crohn Disease/metabolism , Milk Proteins/metabolism , Milk Proteins/pharmacology , Antigens, Surface/metabolism , Extracellular Matrix/metabolism , Myofibroblasts/metabolism , Disease Models, Animal , Mice , Rats
11.
Am J Physiol Cell Physiol ; 327(3): C671-C683, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38912732

ABSTRACT

Fibrostenosing Crohn's disease (CD) represents a challenging clinical condition characterized by the development of symptomatic strictures within the gastrointestinal tract. Despite therapeutic advancements in managing inflammation, the progression of fibrostenotic complications remains a significant concern, often necessitating surgical intervention. Recent investigations have unveiled the pivotal role of smooth muscle cell hyperplasia in driving luminal narrowing and clinical symptomatology. Drawing parallels to analogous inflammatory conditions affecting other organs, such as the airways and blood vessels, sheds light on common underlying mechanisms of muscular hyperplasia. This review synthesizes current evidence to elucidate the mechanisms underlying smooth muscle cell proliferation in CD-associated strictures, offering insights into potential therapeutic targets. By highlighting the emerging significance of muscle thickening as a novel therapeutic target, this review aims to inform future research endeavors and clinical strategies with the goal to mitigate the burden of fibrostenotic complications in CD and other conditions.


Subject(s)
Crohn Disease , Hyperplasia , Muscle, Smooth , Crohn Disease/pathology , Crohn Disease/complications , Humans , Hyperplasia/pathology , Constriction, Pathologic , Animals , Muscle, Smooth/pathology , Muscle, Smooth/metabolism , Fibrosis , Cell Proliferation , Myocytes, Smooth Muscle/pathology , Myocytes, Smooth Muscle/metabolism
12.
Immunology ; 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39108003

ABSTRACT

Group 2 innate lymphoid cells (ILC2s) play a crucial role in the progression of asthma, yet the regulatory mechanisms modulating ILC2 responses in asthma remain underexplored. Human milk oligosaccharides (HMOs), vital non-nutritive components of breast milk, are known to significantly shape immune system development and influence the incidence of allergic diseases. However, their impact on ILC2-driven asthma is not fully understood. Our research reveals that dietary HMOs act as potent inhibitors of ILC2 responses and allergic airway inflammation. Treatment with 2'-fucosyllactose (2'-FL) and 6'-sialyllactose (6'-SL) significantly reduced ILC2-related airway inflammation induced by papain or Alternaria alternata in mice, evidenced by decreased eosinophil (EOS) infiltration and lower IL-5 and IL-13 levels in BALF. Notably, while ILC2 expresses HMO receptors, HMO did not act directly on ILC2 but potentially modulated their activity through alterations in gut microbiota derived SCFAs. HMO treatments alleviated airway inflammation in SCFA-dependent manners, with SCFA depletion or receptor blocking reversing these beneficial effects. This study reveals the potential of dietary HMOs in managing asthma through modulation of ILC2 activity and the gut-lung axis, proposing a new therapeutic avenue that utilises the immunomodulatory capacities of nutritional components to combat respiratory diseases.

13.
J Am Chem Soc ; 146(27): 18592-18605, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38943624

ABSTRACT

Ascorbic acid (AA) has been attracting great attention with its emerging potential in T cell-dependent antitumor immunity. However, premature blood clearance and immunologically "cold" tumors severely compromise its immunotherapeutic outcomes. As such, the reversal of the immunosuppressive tumor microenvironment (TME) has been the premise for improving the effectiveness of AA-based immunotherapy, which hinges upon advanced AA delivery and amplified immune-activating strategies. Herein, a novel Escherichia coli (E. coli) outer membrane vesicle (OMV)-red blood cell (RBC) hybrid membrane (ERm)-camouflaged immunomodulatory nanoturret is meticulously designed based on gating of an AA-immobilized metal-organic framework (MOF) onto bortezomib (BTZ)-loaded magnesium-doped mesoporous silica (MMS) nanovehicles, which can realize immune landscape remodeling by chemotherapy-assisted ascorbate-mediated immunotherapy (CAMIT). Once reaching the acidic TME, the acidity-sensitive MOF gatekeeper and MMS core within the nanoturret undergo stepwise degradation, allowing for tumor-selective sequential release of AA and BTZ. The released BTZ can evoke robust immunogenic cell death (ICD), synergistically promote dendritic cell (DC) maturation in combination with OMV, and ultimately increase T cell tumor infiltration together with Mg2+. The army of T cells is further activated by AA, exhibiting remarkable antitumor and antimetastasis performance. Moreover, the CD8-deficient mice model discloses the T cell-dependent immune mechanism of the AA-based CAMIT strategy. In addition to providing a multifunctional biomimetic hybrid nanovehicle, this study is also anticipated to establish a new immunomodulatory fortification strategy based on the multicomponent-driven nanoturret for highly efficient T cell-activation-enhanced synergistic AA immunotherapy.


Subject(s)
Antineoplastic Agents , Ascorbic Acid , Metal-Organic Frameworks , T-Lymphocytes , Animals , Mice , Metal-Organic Frameworks/chemistry , Ascorbic Acid/chemistry , Ascorbic Acid/pharmacology , T-Lymphocytes/immunology , T-Lymphocytes/drug effects , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Immunotherapy , Bortezomib/chemistry , Bortezomib/pharmacology , Bortezomib/therapeutic use , Biomimetic Materials/chemistry , Biomimetic Materials/pharmacology , Escherichia coli/drug effects , Silicon Dioxide/chemistry , Immunologic Factors/chemistry , Immunologic Factors/pharmacology , Magnesium/chemistry , Nanoparticles/chemistry , Humans , Cell Line, Tumor , Tumor Microenvironment/drug effects , Drug Liberation
14.
Mol Cancer ; 23(1): 141, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982480

ABSTRACT

BACKGROUND: The aberrant expression of phosphofructokinase-platelet (PFKP) plays a crucial role in the development of various human cancers by modifying diverse biological functions. However, the precise molecular mechanisms underlying the role of PFKP in head and neck squamous cell carcinoma (HNSCC) are not fully elucidated. METHODS: We assessed the expression levels of PFKP and c-Myc in tumor and adjacent normal tissues from 120 HNSCC patients. A series of in vitro and in vivo experiments were performed to explore the impact of the feedback loop between PFKP and c-Myc on HNSCC progression. Additionally, we explored the therapeutic effects of targeting PFKP and c-Myc in HNSCC using Patient-Derived Organoids (PDO), Cell Line-Derived Xenografts, and Patients-Derived Xenografts. RESULTS: Our findings indicated that PFKP is frequently upregulated in HNSCC tissues and cell lines, correlating with poor prognosis. Our in vitro and in vivo experiments demonstrate that elevated PFKP facilitates cell proliferation, angiogenesis, and metastasis in HNSCC. Mechanistically, PFKP increases the ERK-mediated stability of c-Myc, thereby driving progression of HNSCC. Moreover, c-Myc stimulates PFKP expression at the transcriptional level, thus forming a positive feedback loop between PFKP and c-Myc. Additionally, our multiple models demonstrate that co-targeting PFKP and c-Myc triggers synergistic anti-tumor effects in HNSCC. CONCLUSION: Our study demonstrates the critical role of the PFKP/c-Myc positive feedback loop in driving HNSCC progression and suggests that simultaneously targeting PFKP and c-Myc may be a novel and effective therapeutic strategy for HNSCC.


Subject(s)
Disease Progression , Feedback, Physiological , Gene Expression Regulation, Neoplastic , Head and Neck Neoplasms , Proto-Oncogene Proteins c-myc , Squamous Cell Carcinoma of Head and Neck , Humans , Squamous Cell Carcinoma of Head and Neck/metabolism , Squamous Cell Carcinoma of Head and Neck/pathology , Squamous Cell Carcinoma of Head and Neck/genetics , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Animals , Mice , Head and Neck Neoplasms/metabolism , Head and Neck Neoplasms/pathology , Head and Neck Neoplasms/genetics , Cell Line, Tumor , Phosphofructokinase-1, Type C/metabolism , Phosphofructokinase-1, Type C/genetics , Cell Proliferation , Prognosis , Female , Male , Xenograft Model Antitumor Assays , Biomarkers, Tumor/metabolism
15.
Gastroenterology ; 164(3): 407-423.e17, 2023 03.
Article in English | MEDLINE | ID: mdl-36574521

ABSTRACT

BACKGROUND & AIMS: Lack of thorough knowledge about the complicated immune microenvironment (IM) within a variety of liver metastases (LMs) leads to inappropriate treatment and unsatisfactory prognosis. We aimed to characterize IM subtypes and investigate potential mechanisms in LMs. METHODS: Mass cytometry was applied to characterize immune landscape of a primary liver cancers and liver metastases cohort. Transcriptomic and whole-exome sequencing were used to explore potential mechanisms across distinct IM subtypes. Single-cell transcriptomic sequencing, multiplex fluorescent immunohistochemistry, cell culture, mouse model, Western blot, quantitative polymerase chain reaction, and immunohistochemistry were used for validation. RESULTS: Five IM subtypes were revealed in 100 LMs and 50 primary liver cancers. Patients featured terminally exhausted (IM1) or rare T-cell-inflamed (IM2 and IM3) immune characteristics showed worse outcome. Increased intratumor heterogeneity, enriched somatic TP53, KRAS, APC, and PIK3CA mutations and hyperactivated hypoxia signaling accounted for the formation of vicious subtypes. SLC2A1 promoted immune suppression and desert via increasing proportion of Spp1+ macrophages and their inhibitory interactions with T cells in liver metastatic lesions. Furthermore, SLC2A1 promoted immune escape and LM through inducing regulatory T cells, including regulatory T cells and LAG3+CD4+ T cells in primary colorectal cancer. CONCLUSIONS: The study provided integrated multi-omics landscape of LM, uncovering potential mechanisms for vicious IM subtypes and confirming the roles of SLC2A1 in regulating tumor microenvironment remodeling in both primary tumor and LM lesions.


Subject(s)
Liver Neoplasms , Multiomics , Animals , Mice , Mutation , Liver Neoplasms/pathology , Exome Sequencing , Tumor Microenvironment
16.
Anal Chem ; 96(5): 2165-2172, 2024 02 06.
Article in English | MEDLINE | ID: mdl-38284353

ABSTRACT

The profiling of multiple glycans on a single cell is important for elucidating glycosylation mechanisms and accurately identifying disease states. Herein, we developed a closed bipolar electrode (BPE) array chip for live single-cell trapping and in situ galactose and sialic acid detection with the electrochemiluminescence (ECL) method. Methylene blue-DNA (MB-DNA) as well as biotin-DNA (Bio-DNA) codecorated AuNPs were prepared as nanoprobes, which were selectively labeled on the cell surface through chemoselective labeling techniques. The individual cell was captured and labeled in the microtrap of the cathodic chamber, under an appropriate potential, MB molecules on the cellular membrane underwent oxidation, triggering the reduction of [Ru(bpy)3]2+/TPA and consequently generating ECL signals in the anodic chamber. The abundance of MB groups on the single cell enabled selective monitoring of both sialic acid and galactosyl groups with high sensitivity using ECL. The sialic acid and galactosyl content per HepG2 cell were detected to be 0.66 and 0.82 fmol, respectively. Through comprehensive evaluation of these two types of glycans on a single cell, tumor cells, and normal cells could be effectively discriminated and the accuracy of single-cell heterogeneous analysis was improved. Additionally, dynamic monitoring of variations in galactosyl groups on the surface of the single cell was also achieved. This work introduced a straightforward and convenient approach for heterogeneity analysis among single cells.


Subject(s)
Biosensing Techniques , Metal Nanoparticles , Luminescent Measurements/methods , Gold , N-Acetylneuraminic Acid , Biosensing Techniques/methods , Electrodes , DNA , Electrochemical Techniques/methods
17.
Anal Chem ; 96(37): 15066-15073, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39225442

ABSTRACT

In this work, by ingeniously integrating catalytic hairpin assembly (CHA), double-end Mg2+-dependent DNAzyme, and hybridization chain reaction (HCR) as a triple cascade signal amplifier, an efficient concatenated CHA-DNAzyme-HCR (CDH) system was constructed to develop an ultrasensitive electrochemical biosensor with a low-background signal for the detection of microRNA-221 (miRNA-221). In the presence of the target miRNA-221, the CHA cycle was initiated by reacting with hairpins H1 and H2 to form DNAzyme structure H1-H2, which catalyzed the cleavage of the substrate hairpin H0 to release two output DNAs (output 1 and output 2). Subsequently, the double-loop hairpin H fixed on the electrode plate was opened by the output DNAs, to trigger the HCR with the assistance of hairpins Ha and Hb. Finally, methylene blue was intercalated into the long dsDNA polymer of the HCR product, resulting in a significant electrochemical signal. Surprisingly, the double-loop structure of the hairpin H could prominently reduce the background signal for enhancing the signal-to-noise ratio (S/N). As a proof of concept, an ultrasensitive electrochemical biosensor was developed using the CDH system with a detection limit as low as 9.25 aM, achieving favorable application for the detection of miRNA-221 in various cancer cell lysates. Benefiting from its enzyme-free, label-free, low-background, and highly sensitive characteristics, the CDH system showed widespread application potential for analyzing trace amounts of biomarkers in various clinical research studies.


Subject(s)
Biosensing Techniques , DNA, Catalytic , Electrochemical Techniques , MicroRNAs , MicroRNAs/analysis , Biosensing Techniques/methods , Humans , DNA, Catalytic/chemistry , DNA, Catalytic/metabolism , Nucleic Acid Hybridization , Limit of Detection , Nucleic Acid Amplification Techniques
18.
Anal Chem ; 96(22): 9218-9227, 2024 06 04.
Article in English | MEDLINE | ID: mdl-38781682

ABSTRACT

In situ monitoring of cell secretions and communications plays a fundamental role in screening of disease diagnostic biomarkers and drugs. Quantitative detection of cell secretions and monitoring of intercellular communication have been separately reported, which often rely on target labeling or complex pretreatment steps, inevitably causing damage to the target. Simultaneous in situ noninvasive detection of cell secretions and monitoring of intercellular communication are challenging and have never been reported. Herein, we smartly developed a portable device for in situ label-free monitoring of cell secretions and communications with fluorescence and ion-transport-based nanochannel electrochemistry. Based on the dual signal mode, a series of nonelectroactive secretions were sensitively and accurately quantified. The detection limits for VEGF, MUC1, and ATP were 3.84 pg/mL, 32.7 pg/mL, and 47.4 fM (3σ/S), which were 1/3.9, 1/1.1, and 1/41 of those of commercial ELISA kits, respectively. More interestingly, under the released secretions, the gradual opening of the nanochannel connected the two cells in the left and right chambers of the device; thus, the secretion mediated intercellular communication can be monitored. The proposed platform may provide a promising tool for understanding the mechanism of intercellular communication and discovering new therapeutic targets.


Subject(s)
Electrochemical Techniques , Humans , Electrochemical Techniques/instrumentation , Adenosine Triphosphate/analysis , Adenosine Triphosphate/metabolism , Mucin-1/analysis , Mucin-1/metabolism , Cell Communication , Vascular Endothelial Growth Factor A/analysis , Vascular Endothelial Growth Factor A/metabolism , Fluorescence , Limit of Detection
19.
Small ; 20(1): e2305200, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37649150

ABSTRACT

Artificially molding exciton flux is the cornerstone for developing promising excitonic devices. In the emerging hetero/homobilayers, the spatial separated charges prolong exciton lifetimes and create out-plane dipoles, facilitating electrically control exciton flux on a large scale, and the nanoscale periodic moiré potentials arising from twist-angle or/and lattice mismatch can substantially alter exciton dynamics, which are mainly proved in the heterostructures. However, the spatially indirect excitons dynamics in homobilayers without lattice mismatch remain elusive. Here the nonequilibrium dynamics of indirect exciton in homobilayers are systematically investigated. The homobilayers with slightly twist-angle can induce a deep moiré potential (>50 meV) in the energy landscape of indirect excitons, resulting in a strongly localized moiré excitons insulating the transport dynamics from phonons and disorder. These findings provide insights into the exciton dynamics and many-body physics in moiré superlattices modulated energy landscape, with implications for designing excitonic devices operating at room temperature.

20.
J Transl Med ; 22(1): 528, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38824544

ABSTRACT

Given the insidious and high-fatality nature of cardiovascular diseases (CVDs), the emergence of fluoride as a newly identified risk factor demands serious consideration alongside traditional risk factors. While vascular smooth muscle cells (VSMCs) play a pivotal role in the progression of CVDs, the toxicological impact of fluoride on VSMCs remains largely uncharted. In this study, we constructed fluorosis model in SD rats and A7R5 aortic smooth muscle cell lines to confirm fluoride impaired VSMCs. Fluoride aggravated the pathological damage of rat aorta in vivo. Then A7R5 were exposed to fluoride with concentration ranging from 0 to 1200 µmol/L over a 24-h period, revealing a dose-dependent inhibition of cell proliferation and migration. The further metabolomic analysis showed alterations in metabolite profiles induced by fluoride exposure, notably decreasing organic acids and lipid molecules level. Additionally, gene network analysis underscored the frequency of fluoride's interference with amino acids metabolism, potentially impacting the tricarboxylic acid (TCA) cycle. Our results also highlighted the ATP-binding cassette (ABC) transporters pathway as a central element in VSMC impairment. Moreover, we observed a dose-dependent increase in osteopontin (OPN) and α-smooth muscle actin (α-SMA) mRNA level and a dose-dependent decrease in ABC subfamily C member 1 (ABCC1) and bestrophin 1 (BEST1) mRNA level. These findings advance our understanding of fluoride as a CVD risk factor and its influence on VSMCs and metabolic pathways, warranting further investigation into this emerging risk factor.


Subject(s)
Amino Acids , Cell Proliferation , Fluorides , Muscle, Smooth, Vascular , Rats, Sprague-Dawley , Animals , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/pathology , Muscle, Smooth, Vascular/drug effects , Fluorides/pharmacology , Cell Line , Amino Acids/metabolism , Cell Proliferation/drug effects , Rats , Cell Movement/drug effects , Male , Aorta/pathology , Aorta/drug effects , Aorta/metabolism , Metabolomics , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/pathology , Gene Regulatory Networks/drug effects
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