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1.
Cell ; 160(1-2): 145-60, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25594178

RESUMO

The epidermal growth factor receptor (EGFR) is upregulated in numerous human cancers. Inhibition of EGFR signaling induces autophagy in tumor cells. Here, we report an unanticipated role for the inactive EGFR in autophagy initiation. Inactive EGFR interacts with the oncoprotein LAPTM4B that is required for the endosomal accumulation of EGFR upon serum starvation. Inactive EGFR and LAPTM4B stabilize each other at endosomes and recruit the exocyst subcomplex containing Sec5. We show that inactive EGFR, LAPTM4B, and the Sec5 subcomplex are required for basal and starvation-induced autophagy. LAPTM4B and Sec5 promote EGFR association with the autophagy inhibitor Rubicon, which in turn disassociates Beclin 1 from Rubicon to initiate autophagy. Thus, the oncoprotein LAPTM4B facilitates the role of inactive EGFR in autophagy initiation. This pathway is positioned to control tumor metabolism and promote tumor cell survival upon serum deprivation or metabolic stress.


Assuntos
Autofagia , Receptores ErbB/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/efeitos dos fármacos , Proteínas Relacionadas à Autofagia , Proteína Beclina-1 , Linhagem Celular Tumoral , Endossomos/metabolismo , Receptores ErbB/antagonistas & inibidores , Cloridrato de Erlotinib , Gefitinibe , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Oncogênicas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Proteínas de Transporte Vesicular/metabolismo
2.
Nature ; 632(8026): 869-876, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38866053

RESUMO

Nucleotide-binding leucine-rich repeat (NLR) proteins play a pivotal role in plant immunity by recognizing pathogen effectors1,2. Maintaining a balanced immune response is crucial, as excessive NLR expression can lead to unintended autoimmunity3,4. Unlike most NLRs, the plant NLR required for cell death 2 (NRC2) belongs to a small NLR group characterized by constitutively high expression without self-activation5. The mechanisms underlying NRC2 autoinhibition and activation are not yet understood. Here we show that Solanum lycopersicum (tomato) NRC2 (SlNRC2) forms dimers and tetramers and higher-order oligomers at elevated concentrations. Cryo-electron microscopy shows an inactive conformation of SlNRC2 in these oligomers. Dimerization and oligomerization not only stabilize the inactive state but also sequester SlNRC2 from assembling into an active form. Mutations at the dimeric or interdimeric interfaces enhance pathogen-induced cell death and immunity in Nicotiana benthamiana. The cryo-electron microscopy structures unexpectedly show inositol hexakisphosphate (IP6) or pentakisphosphate (IP5) bound to the inner surface of the C-terminal leucine-rich repeat domain of SlNRC2, as confirmed by mass spectrometry. Mutations at the inositol phosphate-binding site impair inositol phosphate binding of SlNRC2 and pathogen-induced SlNRC2-mediated cell death in N. benthamiana. Our study indicates a negative regulatory mechanism of NLR activation and suggests inositol phosphates as cofactors of NRCs.


Assuntos
Proteínas NLR , Ácido Fítico , Proteínas de Plantas , Multimerização Proteica , Solanum lycopersicum , Sítios de Ligação , Morte Celular , Microscopia Crioeletrônica , Modelos Moleculares , Mutação , Nicotiana/citologia , Nicotiana/imunologia , Nicotiana/metabolismo , Proteínas NLR/antagonistas & inibidores , Proteínas NLR/química , Proteínas NLR/genética , Proteínas NLR/metabolismo , Proteínas NLR/ultraestrutura , Ácido Fítico/metabolismo , Ácido Fítico/química , Imunidade Vegetal , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/ultraestrutura , Ligação Proteica , Domínios Proteicos , Solanum lycopersicum/citologia , Solanum lycopersicum/genética , Solanum lycopersicum/imunologia , Solanum lycopersicum/metabolismo
3.
Nature ; 610(7931): 335-342, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36131021

RESUMO

Plants rely on cell-surface-localized pattern recognition receptors to detect pathogen- or host-derived danger signals and trigger an immune response1-6. Receptor-like proteins (RLPs) with a leucine-rich repeat (LRR) ectodomain constitute a subgroup of pattern recognition receptors and play a critical role in plant immunity1-3. Mechanisms underlying ligand recognition and activation of LRR-RLPs remain elusive. Here we report a crystal structure of the LRR-RLP RXEG1 from Nicotiana benthamiana that recognizes XEG1 xyloglucanase from the pathogen Phytophthora sojae. The structure reveals that specific XEG1 recognition is predominantly mediated by an amino-terminal and a carboxy-terminal loop-out region (RXEG1(ID)) of RXEG1. The two loops bind to the active-site groove of XEG1, inhibiting its enzymatic activity and suppressing Phytophthora infection of N. benthamiana. Binding of XEG1 promotes association of RXEG1(LRR) with the LRR-type co-receptor BAK1 through RXEG1(ID) and the last four conserved LRRs to trigger RXEG1-mediated immune responses. Comparison of the structures of apo-RXEG1(LRR), XEG1-RXEG1(LRR) and XEG1-BAK1-RXEG1(LRR) shows that binding of XEG1 induces conformational changes in the N-terminal region of RXEG1(ID) and enhances structural flexibility of the BAK1-associating regions of RXEG1(LRR). These changes allow fold switching of RXEG1(ID) for recruitment of BAK1(LRR). Our data reveal a conserved mechanism of ligand-induced heterodimerization of an LRR-RLP with BAK1 and suggest a dual function for the LRR-RLP in plant immunity.


Assuntos
Glicosídeo Hidrolases , Phytophthora , Imunidade Vegetal , Proteínas de Plantas , Receptores de Reconhecimento de Padrão , Motivos de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , Glicosídeo Hidrolases/metabolismo , Leucina/metabolismo , Ligantes , Phytophthora/enzimologia , Phytophthora/imunologia , Phytophthora/fisiologia , Proteínas de Plantas/química , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Multimerização Proteica , Receptores de Reconhecimento de Padrão/química , Receptores de Reconhecimento de Padrão/imunologia , Receptores de Reconhecimento de Padrão/metabolismo , Nicotiana/química , Nicotiana/metabolismo
4.
Nature ; 610(7932): 532-539, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36163289

RESUMO

Plant intracellular nucleotide-binding leucine-rich repeat receptors (NLRs) detect pathogen effectors to trigger immune responses1. Indirect recognition of a pathogen effector by the dicotyledonous Arabidopsis thaliana coiled-coil domain containing NLR (CNL) ZAR1 induces the formation of a large hetero-oligomeric protein complex, termed the ZAR1 resistosome, which functions as a calcium channel required for ZAR1-mediated immunity2-4. Whether the resistosome and channel activities are conserved among plant CNLs remains unknown. Here we report the cryo-electron microscopy structure of the wheat CNL Sr355 in complex with the effector AvrSr356 of the wheat stem rust pathogen. Direct effector binding to the leucine-rich repeats of Sr35 results in the formation of a pentameric Sr35-AvrSr35 complex, which we term the Sr35 resistosome. Wheat Sr35 and Arabidopsis ZAR1 resistosomes bear striking structural similarities, including an arginine cluster in the leucine-rich repeats domain not previously recognized as conserved, which co-occurs and forms intramolecular interactions with the 'EDVID' motif in the coiled-coil domain. Electrophysiological measurements show that the Sr35 resistosome exhibits non-selective cation channel activity. These structural insights allowed us to generate new variants of closely related wheat and barley orphan NLRs that recognize AvrSr35. Our data support the evolutionary conservation of CNL resistosomes in plants and demonstrate proof of principle for structure-based engineering of NLRs for crop improvement.


Assuntos
Canais de Cálcio , Microscopia Crioeletrônica , Proteínas NLR , Proteínas de Plantas , Receptores Imunológicos , Triticum , Arabidopsis/imunologia , Arabidopsis/metabolismo , Arginina , Canais de Cálcio/química , Canais de Cálcio/imunologia , Canais de Cálcio/metabolismo , Cátions/metabolismo , Leucina , Proteínas NLR/química , Proteínas NLR/imunologia , Proteínas NLR/metabolismo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal , Proteínas de Plantas/química , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Receptores Imunológicos/química , Receptores Imunológicos/imunologia , Receptores Imunológicos/metabolismo , Triticum/imunologia , Triticum/metabolismo , Motivos de Aminoácidos , Sequência Conservada , Eletrofisiologia
5.
Trends Biochem Sci ; 48(9): 776-787, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37394345

RESUMO

Nucleotide binding and leucine-rich repeat-containing receptors (NLRs) have a critical role in plant immunity through direct or indirect recognition of pathogen effectors. Recent studies have demonstrated that such recognition induces formation of large protein complexes called resistosomes to mediate NLR immune signaling. Some NLR resistosomes activate Ca2+ influx by acting as Ca2+-permeable channels, whereas others function as active NADases to catalyze the production of nucleotide-derived second messengers. In this review we summarize these studies on pathogen effector-induced assembly of NLR resistosomes and resistosome-mediated production of the second messengers of Ca2+ and nucleotide derivatives. We also discuss downstream events and regulation of resistosome signaling.


Assuntos
Proteínas NLR , Plantas , Proteínas NLR/química , Proteínas NLR/metabolismo , Transdução de Sinais , Sistemas do Segundo Mensageiro , Nucleotídeos/metabolismo
6.
Proc Natl Acad Sci U S A ; 121(7): e2313789121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38335257

RESUMO

Bats are associated with the circulation of most mammalian filoviruses (FiVs), with pathogenic ones frequently causing deadly hemorrhagic fevers in Africa. Divergent FiVs have been uncovered in Chinese bats, raising concerns about their threat to public health. Here, we describe a long-term surveillance to track bat FiVs at orchards, eventually resulting in the identification and isolation of a FiV, Dehong virus (DEHV), from Rousettus leschenaultii bats. DEHV has a typical filovirus-like morphology with a wide spectrum of cell tropism. Its entry into cells depends on the engagement of Niemann-Pick C1, and its replication is inhibited by remdesivir. DEHV has the largest genome size of filoviruses, with phylogenetic analysis placing it between the genera Dianlovirus and Orthomarburgvirus, suggesting its classification as the prototype of a new genus within the family Filoviridae. The continuous detection of viral RNA in the serological survey, together with the wide host distribution, has revealed that the region covering southern Yunnan, China, and bordering areas is a natural circulation sphere for bat FiVs. These emphasize the need for a better understanding of the pathogenicity and potential risk of FiVs in the region.


Assuntos
Quirópteros , Filoviridae , Animais , Filogenia , China , Mamíferos
7.
Proc Natl Acad Sci U S A ; 120(36): e2215710120, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37639606

RESUMO

The beginnings of words are, in some informal sense, special. This intuition is widely shared, for example, when playing word games. Less apparent is whether the intuition is substantiated empirically and what the underlying organizational principle(s) might be. Here, we answer this seemingly simple question in a quantitatively clear way. Based on arguments about the interplay between lexical storage and speech processing, we examine whether the distribution of information among different speech sounds of words is governed by a critical computational unit for online speech perception and production: syllables. By analyzing lexical databases of twelve languages, we demonstrate that there is a compelling asymmetry between syllable beginnings (onsets) versus ends (codas) in their involvement in distinguishing words stored in the lexicon. In particular, we show that the functional advantage of syllable onset reflects an asymmetrical distribution of lexical informativeness within the syllable unit but not an effect of a global decay of informativeness from the beginning to the end of a word. The converging finding across languages from a range of typological families supports the conjecture that the syllable unit, while being a critical primitive for both speech perception and production, is also a key organizational constraint for lexical storage.


Assuntos
Dissidências e Disputas , Intuição , Humanos , Bases de Dados Factuais , Idioma , Fala
8.
Proc Natl Acad Sci U S A ; 120(39): e2302801120, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37722038

RESUMO

Primary cilia are specialized organelles supporting the development and function of cells and organisms. Intraflagellar transport (IFT) is essential for cilia formation, maintenance, and function. In C. elegans ciliated sensory neurons, IFT interacts with signaling molecules to generate distinct morphological and function features and also to maintain the integrity of cilia. Here, we report an IFT-dependent feedback control on the conserved MAPKKK DLK-1 in the ciliated sensory neurons. DLK proteins are widely known to act in synapse formation, axon regeneration, and degeneration, but their roles in other neuronal compartments are understudied. By forward genetic screening for altered expression of the endogenously tagged DLK-1 we identified multiple ift mutants showing increased DLK-1 accumulation in the defective sensory endings. We show that in response to acute IFT disruption, DLK-1 accumulates rapidly and reversibly. The expression levels of the transcription factor CEBP-1, known to act downstream of DLK-1 in the development and maintenance of synapses and axons, are also increased in the ciliated sensory neurons of ift mutants. Interestingly, the regulation of CEBP-1 expression shows sensory neuron-type dependency on DLK-1. Moreover, in the sensory neuron AWC, which has elaborate cilia morphology, up-regulated CEBP-1 represses DLK-1 at the transcription level, thereby dampening DLK-1 accumulation. Last, the IFT-dependent regulatory loop of DLK-1 and CEBP-1 offers neuroprotection in a cilia degeneration model. These findings uncover a surveillance mechanism in which tight control on the DLK-1 signaling protects cilia integrity in a context-specific manner.


Assuntos
Proteínas de Caenorhabditis elegans , Cílios , Animais , Cílios/genética , Retroalimentação , Axônios , Caenorhabditis elegans/genética , Regeneração Nervosa , Células Receptoras Sensoriais , MAP Quinase Quinase Quinases , Proteínas de Caenorhabditis elegans/genética
9.
Proc Natl Acad Sci U S A ; 120(35): e2302800120, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37607225

RESUMO

The adiabatic elastocaloric effect measures the temperature change of a given system with strain and provides a thermodynamic probe of the entropic landscape in the temperature-strain space. Here, we demonstrate that the DC bias strain-dependence of AC elastocaloric effect allows decomposition of the latter into symmetric (rotation-symmetry-preserving) and antisymmetric (rotation-symmetry-breaking) strain channels, using a tetragonal [Formula: see text]-electron intermetallic DyB[Formula: see text]C[Formula: see text]-whose antiferroquadrupolar order breaks local fourfold rotational symmetries while globally remaining tetragonal-as a showcase example. We capture the strain evolution of its quadrupolar and magnetic phase transitions using both singularities in the elastocaloric coefficient and its jumps at the transitions, and the latter we show follows a modified Ehrenfest relation. We find that antisymmetric strain couples to the underlying order parameter in a biquadratic (linear-quadratic) manner in the antiferroquadrupolar (canted antiferromagnetic) phase, which are attributed to a preserved (broken) global tetragonal symmetry, respectively. The broken tetragonal symmetry in the magnetic phase is further evidenced by elastocaloric strain-hysteresis and optical birefringence. Additionally, within the staggered quadrupolar order, the observed elastocaloric response reflects a quadratic increase of entropy with antisymmetric strain, analogous to the role magnetic field plays for Ising antiferromagnetic orders by promoting pseudospin flips. Our results demonstrate AC elastocaloric effect as a compact and incisive thermodynamic probe into the coupling between electronic degrees of freedom and strain in free energy, which holds the potential for investigating and understanding the symmetry of a wide variety of ordered phases in broader classes of quantum materials.

10.
Proc Natl Acad Sci U S A ; 120(21): e2220589120, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186856

RESUMO

The propagation of spin waves in magnetically ordered systems has emerged as a potential means to shuttle quantum information over large distances. Conventionally, the arrival time of a spin wavepacket at a distance, d, is assumed to be determined by its group velocity, vg. Here, we report time-resolved optical measurements of wavepacket propagation in the Kagome ferromagnet Fe3Sn2 that demonstrate the arrival of spin information at times significantly less than d/vg. We show that this spin wave "precursor" originates from the interaction of light with the unusual spectrum of magnetostatic modes in Fe3Sn2. Related effects may have far-reaching consequences toward realizing long-range, ultrafast spin wave transport in both ferromagnetic and antiferromagnetic systems.

11.
Acc Chem Res ; 57(1): 164-174, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38117659

RESUMO

The molecular design of many peptide-based materials originates from structural proteins identified in living organisms. Prominent examples that have garnered broad interdisciplinary research interest (chemistry, materials science, bioengineering, etc.) include elastin, silk, or mussel adhesive proteins. The critical first steps in this type of research are to identify a convenient model system of interest followed by sequencing the prevailing proteins from which these biological structures are assembled. In our laboratory, the main model systems for many years have been the hard biotools of cephalopods, particularly their parrot-like tough beak and their sucker ring teeth (SRT) embedded within the sucker cuptions that line the interior surfaces of their arms and tentacles. Unlike the majority of biological hard tissues, these structures are devoid of biominerals and consist of protein/polysaccharide biomolecular composites (the beak) or, in the case of SRT, are entirely made of proteins that are assembled by supramolecular interactions.In this Account, we chronicle our journey into the discovery of these intriguing biological materials. We initially focus on their excellent mechanical robustness followed by the identification and sequencing of the structural proteins from which they are built, using the latest "omics" techniques including next-generation sequencing and high-throughput proteomics. A common feature of these proteins is their modular architecture at the molecular level consisting of short peptide repeats. We describe the molecular design of these peptide building blocks, highlighting the consensus motifs identified to play a key role in biofabrication and in regulating the mechanical properties of the macroscopic biological material. Structure/property relationships unveiled through advanced spectroscopic and scattering techniques, including Raman, infrared, circular dichroism, and NMR spectroscopies as well as wide-angle and small-angle X-ray scattering, are also discussed.We then present recent developments in exploiting the discovered molecular designs to engineer peptides and their conjugates for promising biomedical applications. One example includes short peptide hydrogels that self-assemble entirely under aqueous conditions and simultaneously encapsulate large macromolecules during the gelation process. A second example involves peptide coacervate microdroplets produced by liquid-liquid phase separation. These microdroplets are capable of recruiting and delivering large macromolecular therapeutics (genes, mRNA, proteins, peptides, CRISPR/Cas 9 modalities, etc.) into mammalian cells, which introduces exciting prospects in cancer, gene, and immune therapies.This Account also serves as a testament to how curiosity-driven explorations, which may lack an obvious practical goal initially, can lead to discoveries with unexpected and promising translational potential.


Assuntos
Decapodiformes , Comportamento Exploratório , Animais , Decapodiformes/genética , Peptídeos/química , Seda , Substâncias Macromoleculares , Mamíferos
12.
Ann Neurol ; 96(1): 74-86, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38501714

RESUMO

OBJECTIVE: To determine the association between the preoperative Bioenergetic Health Index (BHI) of platelets and the occurrence of postoperative delirium (POD) in elderly patients. METHODS: Elderly patients scheduled for major abdominal surgery under general anesthesia were included. The presence of POD was assessed within the 3 days after surgery. Seahorse XF analysis and transmission electron microscopy were utilized to evaluate the mitochondrial metabolism and morphology of platelets. RESULTS: A total of 20 out of 162 participants developed POD. Participants with POD showed lower preoperative Mini-Mental State Examination scores and total protein levels, fewer educational years, longer surgery duration, higher mean platelet volume, and lower platelet BHI compared with those without POD. Damaged mitochondria with swollen appearance and distorted cristae was detected in platelets from participants with POD. Preoperative platelet BHI was independently associated with the occurrence of POD after adjusting for age, education, preoperative Mini-Mental State Examination score, preoperative mean platelet volume and total protein levels, surgical type and duration, and lymphocyte counts on the first postoperative day (OR 0.11, 95% CI 0.03-0.37, p < 0.001). The areas under the receiver operating curves for predicting POD were 0.83 (95% CI 0.76-0.88) for platelet BHI. It showed a sensitivity of 85.00% and specificity of 73.24%, with an optimal cutoff value of 1.61. Using a serial combination (mean platelet volume followed by BHI) yielded a sensitivity of 80.00% and specificity of 82.39%. INTERPRETATION: Preoperative platelet BHI was independently associated with the occurrence of POD in elderly patients and has the potential as a screening biomarker for POD risk. ANN NEUROL 2024;96:74-86.


Assuntos
Biomarcadores , Plaquetas , Mitocôndrias , Complicações Pós-Operatórias , Humanos , Idoso , Masculino , Feminino , Plaquetas/metabolismo , Biomarcadores/sangue , Mitocôndrias/metabolismo , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/sangue , Idoso de 80 Anos ou mais , Delírio/sangue , Delírio/diagnóstico , Delírio/etiologia
13.
Nano Lett ; 24(29): 8929-8939, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38865330

RESUMO

Bioorthogonal chemistry represents a powerful tool in chemical biology, which shows great potential in epigenetic modulation. As a proof of concept, the epigenetic modulation model of mitochondrial DNA (mtDNA) is selected because mtDNA establishes a relative hypermethylation stage under oxidative stress, which impairs the mitochondrion-based therapeutic effect during cancer therapy. Herein, we design a new biocompatible hydrogen-bonded organic framework (HOF) for a HOF-based mitochondrion-targeting bioorthogonal platform TPP@P@PHOF-2. PHOF-2 can activate a prodrug (pro-procainamide) in situ, which can specifically inhibit DNA methyltransferase 1 (DNMT1) activity and remodel the epigenetic modification of mtDNA, making it more susceptible to ROS damage. In addition, PHOF-2 can also catalyze artemisinin to produce large amounts of ROS, effectively damaging mtDNA and achieving better chemodynamic therapy demonstrated by both in vitro and in vivo studies. This work provides new insights into developing advanced bioorthogonal therapy and expands the applications of HOF and bioorthogonal catalysis.


Assuntos
DNA Mitocondrial , Epigênese Genética , Mitocôndrias , Espécies Reativas de Oxigênio , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Humanos , DNA Mitocondrial/genética , Epigênese Genética/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Ligação de Hidrogênio , Animais , Camundongos , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferase 1/genética , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia
14.
Nano Lett ; 24(35): 11002-11011, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39166738

RESUMO

Early stage hepatocellular carcinoma (HCC) presents a formidable challenge in clinical settings due to its asymptomatic progression and the limitations of current imaging techniques in detecting micro-HCC lesions. Addressing this critical issue, we introduce a novel ultrathin gadolinium-oxide (Gd-oxide) nanosheet-based platform with heightened sensitivity for high-field MRI and as a therapeutic agent for HCC. Synthesized via a digestive ripening process, these Gd-oxide nanosheets exhibit an exceptional acid-responsive profile. The integration of the ultrathin Gd-oxide with an acid-responsive polymer creates an ultrasensitive high-field MRI probe, enabling the visualization of submillimeter-sized tumors with superior sensitivity. Our research underscores the ultrasensitive probe's efficacy in the treatment of orthotopic HCC. Notably, the ultrasensitive probe functions dually as a companion diagnostic tool, facilitating simultaneous imaging and therapy with real-time treatment monitoring capabilities. In conclusion, this study showcases an innovative companion diagnostic tool that holds promise for the early detection and effective treatment of micro-HCC.


Assuntos
Carcinoma Hepatocelular , Meios de Contraste , Gadolínio , Neoplasias Hepáticas , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico por imagem , Humanos , Gadolínio/química , Meios de Contraste/química , Animais , Camundongos , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Linhagem Celular Tumoral
15.
J Proteome Res ; 23(8): 3367-3382, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39012622

RESUMO

Lactylation (Kla), a recently discovered post-translational modification derived from lactate, plays crucial roles in various cellular processes. However, the specific influence of lactylation on the biological processes underlying hypertrophic scar formation remains unclear. In this study, we present a comprehensive profiling of the lactylome and proteome in both hypertrophic scars and adjacent normal skin tissues. A total of 1023 Kla sites originating from 338 nonhistone proteins were identified based on lactylome analysis. Proteome analysis in hypertrophic scar and adjacent skin samples revealed the identification of 2008 proteins. It is worth noting that Kla exhibits a preference for genes associated with ribosome function as well as glycolysis/gluconeogenesis in both normal skin and hypertrophic scar tissues. Furthermore, the functional enrichment analysis demonstrated that differentially lactyled proteins are primarily involved in proteoglycans, HIF-1, and AMPK signaling pathways. The combined analysis of the lactylome and proteome data highlighted a significant upregulation of 14 lactylation sites in hypertrophic scar tissues. Overall, our investigation unveiled the significant involvement of protein lactylation in the regulation of ribosome function as well as glycolysis/gluconeogenesis, potentially contributing to the formation of hypertrophic scars.


Assuntos
Cicatriz Hipertrófica , Proteoma , Humanos , Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/genética , Cicatriz Hipertrófica/patologia , Proteoma/análise , Proteoma/metabolismo , Proteoma/genética , Transdução de Sinais , Processamento de Proteína Pós-Traducional , Pele/metabolismo , Pele/patologia , Glicólise/genética , Feminino , Proteômica/métodos , Masculino , Ribossomos/metabolismo , Ribossomos/genética , Adulto
16.
Lab Invest ; 104(6): 102058, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38626874

RESUMO

In clinical practice, programmed death ligand 1 (PD-L1) detection is prone to nonspecific staining due to the complex cellular composition of pleural effusion smears. In this study, diaminobenzidine (DAB) and 3-amino-9-ethylcarbazole (AEC) immunohistochemistry double staining was performed to investigate PD-L1 expression in tumor cells from malignant pleural effusion (MPE). MPE was considered as a metastasis in non-small cell lung cancer patients; thus, the heterogeneity between metastatic and primary lung cancer was revealed as well. Ninety paired specimens of MPE cell blocks and matched primary lung cancer tissues from non-small cell lung cancer patients were subjected to PD-L1 and thyroid transcription factor-1(TTF-1)/p63 immunohistochemistry double staining. Two experienced pathologists independently evaluated PD-L1 expression using 3 cutoffs (1%, 10%, and 50%). PD-L1 expression in MPE was strongly correlated with that in matched primary lung cancer tissues (R = 0.813; P < .001). Using a 4-tier scale (cutoffs: 1%, 10%, and 50%), the concordance was 71.1% (Cohen's κ = .534). Using a 2-tier scale, the concordance was 75.6% (1%, Cohen's κ = 0.53), 78.9% (10%, Cohen's κ = 0.574), and 95.6% (50%, Cohen's κ = 0.754). The rates of PD-L1 positivity in MPE (56.7%) were higher than that in lung tissues (32.2%). All 27 discordant cases had higher scores in MPE. The double-staining method provided superior identification of PD-L1-positive tumor cells on a background with nonspecific staining. In conclusion, PD-L1 expression was moderately concordant between metastatic MPE cell blocks and matched primary lung carcinoma tissues, with variability related to tumor heterogeneity. MPE should be considered to detect PD-L1 when histological specimens are unattainable, especially when PD-L1 expression is >50%. PD-L1 positivity rates were higher in MPE. Double staining can improve PD-L1 detection by reducing false-negative/positive results.


Assuntos
Antígeno B7-H1 , Carcinoma Pulmonar de Células não Pequenas , Imuno-Histoquímica , Neoplasias Pulmonares , Humanos , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Derrame Pleural Maligno/metabolismo , Derrame Pleural Maligno/patologia , Idoso de 80 Anos ou mais , Adulto , Biomarcadores Tumorais/metabolismo
17.
Cancer Sci ; 115(1): 109-124, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38015097

RESUMO

Lung adenocarcinoma (LUAD) is the most common subtype of lung cancer. Most patients are diagnosed at an advanced stage, therefore it is crucial to identify novel prognostic biomarkers for LUAD. As important regulatory cells, inducible regulatory T cells (iTregs) play a vital role in immune suppression and are important for the maintenance of immune homeostasis. This study explored the prognostic value and therapeutic effects of iTreg-related genes in LUAD. Data for LUAD patients, including immune infiltration data, RNA sequencing data, and clinical features, were acquired from The Cancer Genome Atlas, Gene Expression Omnibus, and Tumor Immune Single-cell Hub 2 databases. Immune-related subgroups with different infiltration patterns and iTreg-related genes were identified through univariate and multivariate Cox regression analyses and weighted correlation network analysis. Functional enrichment analyses were performed to explore the underlying mechanisms of iTreg-related genes. A prognostic risk signature was constructed using Cox regression analysis with the least absolute shrinkage and selection operator penalty. The ESTIMATE algorithm was applied to determine the immune status of LUAD patients. We applied the constructed signature to predict chemosensitivity and performed single-cell RNA sequencing analysis. The infiltration of iTregs was identified as an independent factor for predicting patient outcomes. We constructed a prognostic signature based on seven iTreg-related genes (GIMAP5, SLA, MS4A7, ZNF366, POU2AF1, MRPL12, and COL5A1), which was applied to subdivide patients into high- and low-risk subgroups. Our results revealed that patients in the iTreg-related low-risk subgroup had a better prognosis and possibly greater sensitivity to traditional chemotherapy. Our study provides a novel iTreg-related signature to elucidate the mechanisms underlying LUAD prognosis and promote individualized chemotherapy treatment.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Prognóstico , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/genética , Fatores de Transcrição , Algoritmos
18.
Biochem Biophys Res Commun ; 694: 149414, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38145596

RESUMO

Glaucoma is a chronic blinding eye disease caused by the progressive loss of retinal ganglion cells (RGCs). Currently, no clinically approved treatment can directly improve the survival rate of RGCs. The Apolipoprotein E (APOE) gene is closely related to the genetic risk of numerous neurodegenerative diseases and has become a hot topic in the field of neurodegenerative disease research in recent years. The optic nerve and retina are extensions of the brain's nervous system. The pathogenesis of retinal degenerative diseases is closely related to the degenerative diseases of the nerves in the brain. APOE consists of three alleles, ε4, ε3, and ε2, in a single locus. They have varying degrees of risk for glaucoma. APOE4 and the APOE gene deletion (APOE-/-) can reduce RGC loss. By contrast, APOE3 and the overall presence of APOE genes (APOE+/+) result in significant loss of RGC bodies and axons, increasing the risk of glaucoma RGCs death. Currently, there is no clear literature indicating that APOE2 is beneficial or harmful to glaucoma. This study summarises the mechanism of different APOE genes in glaucoma and speculates that APOE targeted intervention may be a promising method for protecting against RGCs loss in glaucoma.


Assuntos
Glaucoma , Doenças Neurodegenerativas , Degeneração Retiniana , Humanos , Apolipoproteínas E/genética , Glaucoma/genética , Retina/patologia
19.
Small ; 20(31): e2310398, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38461535

RESUMO

Flexible magnesium (Mg)-air batteries provide an ideal platform for developing efficient energy-storage devices toward wearable electronics and bio-integrated power sources. However, high-capacity bio-adaptable Mg-air batteries still face the challenges in low discharge potential and inefficient oxygen electrodes, with poor kinetics property toward oxygen reduction reaction (ORR). Herein, spinel nickel cobalt oxides (NiCo2O4) nanowires immobilized on nitrogen-doped Ti3C2Tx (NiCo2O4/N-Ti3C2Tx) are reported via surface chemical-bonded effect as oxygen electrodes, wherein surface-doped pyridinic-N-C and Co-pyridinic-N moieties accounted for efficient ORR owing to increased interlayer spacing and changed surrounding environment around Co metals in NiCo2O4. Importantly, in polyethylene glycol (PVA)-NaCl neutral gel electrolytes, the NiCo2O4/N-Ti3C2Tx-assembled quasi-solid wearable Mg-air batteries delivered high open-circuit potential of 1.5 V, good flexibility under various bent angles, high power density of 9.8 mW cm-2, and stable discharge duration to 12 h without obvious voltage drop at 5 mA cm-2, which can power a blue flexible light-emitting diode (LED) array and red smart rollable wearable device. The present study stimulates studies to investigate Mg-air batteries involving human-body adaptable neutral electrolytes, which will facilitate the application of Mg-air batteries in portable, flexible, and wearable power sources for electronic devices.

20.
Small ; : e2406629, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39279370

RESUMO

Infected wounds are a complex disease involving bacterial infections and dysregulated inflammation. However, current research has mostly focused on bacterial inhibition rather than on inflammation. Thus, combined therapeutic strategies with anti-bacterial and anti-inflammation efficacies are urgently needed. Antibiotics are the main treatment strategy for infections. However, the excessive use of antibiotics throughout the body can cause serious side effects. In addition, miRNA-based therapeutics are superior for the treatment of wounds, but their rapid degradation and poor cellular uptake limit their clinical application. Tetrahedral framework DNA (tFNA) is an ideal drug delivery system owing to its excellent stability and remarkable transport ability. Herein, a novel multi-functional miRNA and antibiotic co-delivery system based on tFNA is presented for the first time, called B/L. B/L has heightened resistance to serum and excellent codelivery ability. After transdermal administration, B/L can specifically target TNF receptor-associated factor 6(TRAF6) and IL-1receptor-associated kinase 1(IRAK1), thereby regulating nuclear factor kappa-B (NF-𝜿B) and thus effectively reducing inflammation and promoting the healing of infected wounds. This novel multi-functional co-delivery system provides a versatile, simple, biocompatible, and powerful platform for the personalized and combined treatment of multiple diseases.

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