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1.
Cell ; 185(16): 2918-2935.e29, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35803260

RESUMO

Neoadjuvant immune checkpoint blockade has shown promising clinical activity. Here, we characterized early kinetics in tumor-infiltrating and circulating immune cells in oral cancer patients treated with neoadjuvant anti-PD-1 or anti-PD-1/CTLA-4 in a clinical trial (NCT02919683). Tumor-infiltrating CD8 T cells that clonally expanded during immunotherapy expressed elevated tissue-resident memory and cytotoxicity programs, which were already active prior to therapy, supporting the capacity for rapid response. Systematic target discovery revealed that treatment-expanded tumor T cell clones in responding patients recognized several self-antigens, including the cancer-specific antigen MAGEA1. Treatment also induced a systemic immune response characterized by expansion of activated T cells enriched for tumor-infiltrating T cell clonotypes, including both pre-existing and emergent clonotypes undetectable prior to therapy. The frequency of activated blood CD8 T cells, notably pre-treatment PD-1-positive KLRG1-negative T cells, was strongly associated with intra-tumoral pathological response. These results demonstrate how neoadjuvant checkpoint blockade induces local and systemic tumor immunity.


Assuntos
Neoplasias , Receptor de Morte Celular Programada 1 , Linfócitos T CD8-Positivos , Humanos , Imunoterapia , Linfócitos do Interstício Tumoral , Terapia Neoadjuvante , Neoplasias/terapia , Microambiente Tumoral
2.
Mol Cell ; 80(2): 263-278.e7, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33022274

RESUMO

Cancer metastasis accounts for the major cause of cancer-related deaths. How disseminated cancer cells cope with hostile microenvironments in secondary site for full-blown metastasis is largely unknown. Here, we show that AMPK (AMP-activated protein kinase), activated in mouse metastasis models, drives pyruvate dehydrogenase complex (PDHc) activation to maintain TCA cycle (tricarboxylic acid cycle) and promotes cancer metastasis by adapting cancer cells to metabolic and oxidative stresses. This AMPK-PDHc axis is activated in advanced breast cancer and predicts poor metastasis-free survival. Mechanistically, AMPK localizes in the mitochondrial matrix and phosphorylates the catalytic alpha subunit of PDHc (PDHA) on two residues S295 and S314, which activates the enzymatic activity of PDHc and alleviates an inhibitory phosphorylation by PDHKs, respectively. Importantly, these phosphorylation events mediate PDHc function in cancer metastasis. Our study reveals that AMPK-mediated PDHA phosphorylation drives PDHc activation and TCA cycle to empower cancer cells adaptation to metastatic microenvironments for metastasis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Ciclo do Ácido Cítrico , Complexo Piruvato Desidrogenase/metabolismo , Animais , Domínio Catalítico , Linhagem Celular Tumoral , Sobrevivência Celular , Ativação Enzimática , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Fosforilação , Fosfosserina/metabolismo , Transdução de Sinais , Estresse Fisiológico , Análise de Sobrevida
3.
EMBO J ; 42(1): e111139, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36382711

RESUMO

Hirschsprung disease (HSCR), one of several neurocristopathies in children, is characterized by nerve loss in the large intestine and is mainly treated by surgery, which causes severe complications. Enteric neural crest-derived cell (ENCC) transplantation is a potential therapeutic strategy; however, so far with poor efficacy. Here, we assessed whether and how fecal microbiota transplantation (FMT) could improve ENCC transplantation in a rat model of hypoganglionosis; a condition similar to HSCR, with less intestinal innervation. We found that the hypoganglionosis intestinal microenvironment negatively influenced the ENCC functional phenotype in vitro and in vivo. Combining 16S rDNA sequencing and targeted mass spectrometry revealed microbial dysbiosis and reduced short-chain fatty acid (SCFA) production in the hypoganglionic gut. FMT increased the abundance of Bacteroides and Clostridium, SCFA production, and improved outcomes following ENCC transplantation. SCFAs alone stimulated ENCC proliferation, migration, and supported ENCC transplantation. Transcriptome-wide mRNA sequencing identified MAPK signaling as the top differentially regulated pathway in response to SCFA exposure, and inhibition of MEK1/2 signaling abrogated the SCFA-mediated effects on ENCC. This study demonstrates that FMT improves cell therapy for hypoganglionosis via short-chain fatty acid metabolism-induced MEK1/2 signaling.


Assuntos
Transplante de Microbiota Fecal , Doença de Hirschsprung , Ratos , Animais , Doença de Hirschsprung/terapia , Doença de Hirschsprung/genética , Doença de Hirschsprung/metabolismo , Transdução de Sinais , Ácidos Graxos Voláteis/metabolismo , Terapia Baseada em Transplante de Células e Tecidos
4.
Proc Natl Acad Sci U S A ; 121(14): e2316564121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38527200

RESUMO

Sulfur in nature consists of two abundant stable isotopes, with two more neutrons in the heavy one (34S) than in the light one (32S). The two isotopes show similar physicochemical properties and are usually considered an integral system for chemical research in various fields. In this work, a model study based on a Li-S battery was performed to reveal the variation between the electrochemical properties of the two S isotopes. Provided with the same octatomic ring structure, the cyclo-34S8 molecules form stronger S-S bonds than cyclo-32S8 and are more prone to react with Li. The soluble Li polysulfides generated by the Li-34S conversion reaction show a stronger cation-solvent interaction yet a weaker cation-anion interaction than the 32S-based counterparts, which facilitates quick solvation of polysulfides yet hinders their migration from the cathode to the anode. Consequently, the Li-34S cell shows improved cathode reaction kinetics at the solid-liquid interface and inhibited shuttle of polysulfides through the electrolyte so that it demonstrates better cycling performance than the Li-32S cell. Based on the varied shuttle kinetics of the isotopic-S-based polysulfides, an electrochemical separation method for 34S/32S isotope is proposed, which enables a notably higher separation factor than the conventional separation methods via chemical exchange or distillation and brings opportunities to low-cost manufacture, utilization, and research of heavy chalcogen isotopes.

5.
Trends Genet ; 38(6): 521-523, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35232614

RESUMO

Variant annotation is one of the most essential steps in selecting candidates for further investigation. With the advancement in functional genomics, new variant annotation tools focus on annotation based on empirically generated data instead of theoretically based predictions. This is a direct result of the large national and international consortia that generated enormous experiment-based or validated data at multiple omics levels. Here, we highlight the recent empirically based annotation methods and discuss their strengths and weaknesses.


Assuntos
Genômica , Software , Anotação de Sequência Molecular
6.
Genome Res ; 32(10): 1930-1940, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36100435

RESUMO

Mutation density patterns reveal unique biological properties of specific genomic regions and shed light on the mechanisms of carcinogenesis. Although previous studies reported insightful mutation density patterns associated with certain genomic regions such as transcription start sites and DNA replication origins, a tool that can systematically investigate mutational spatial patterns is still lacking. Thus, we developed MutDens, a bioinformatic tool for comprehensive analysis of mutation density patterns around genomic features, namely, genomic positions, in humans and model species. By scanning the bidirectional vicinity regions of given positions, MutDens systematically characterizes the mutation density for single-base substitution mutational classes after adjusting for total mutation burden and local nucleotide proportion. Analysis results using MutDens not only verified the previously reported transcriptional strand bias around transcription start sites and replicative strand bias around DNA replication origins, but also identified novel mutation density patterns around other genomics features, such as enhancers and retrotransposon insertion polymorphism sites. To our knowledge, MutDens is the first tool that systematically calculates, examines, and compares mutation density patterns, thus providing a valuable avenue for investigating the mutational landscapes associated with important genomic features.


Assuntos
Genômica , Origem de Replicação , Humanos , Mutação , Sítio de Iniciação de Transcrição , DNA
7.
Nat Methods ; 19(3): 359-369, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35277709

RESUMO

Long-term visualization of the dynamic interactions between intracellular structures throughout the three-dimensional space of whole live cells is essential to better understand their functions, but this task remains challenging due to the limitations of existing three-dimensional fluorescence microscopy techniques, such as an insufficient axial resolution, low volumetric imaging rate and photobleaching. Here, we present the combination of a progressive deep-learning super-resolution strategy with a double-ring-modulated selective plane illumination microscopy design capable of visualizing the dynamics of intracellular structures in live cells for hours at an isotropic spatial resolution of roughly 100 nm in three dimensions at speeds up to roughly 17 Hz. Using this approach, we reveal the complex spatial relationships and interactions between endoplasmic reticulum (ER) and mitochondria throughout live cells, providing new insights into ER-mediated mitochondrial division. We also examined the motion of Drp1 oligomers involved in mitochondrial fission and revealed the dynamic interactions between Drp1 and mitochondria in three dimensions.


Assuntos
Retículo Endoplasmático , Mitocôndrias , Retículo Endoplasmático/metabolismo , Imageamento Tridimensional/métodos , Microscopia de Fluorescência/métodos , Fotodegradação
8.
Brief Bioinform ; 24(4)2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37195815

RESUMO

Drug-drug interactions (DDI) may lead to adverse reactions in human body and accurate prediction of DDI can mitigate the medical risk. Currently, most of computer-aided DDI prediction methods construct models based on drug-associated features or DDI network, ignoring the potential information contained in drug-related biological entities such as targets and genes. Besides, existing DDI network-based models could not make effective predictions for drugs without any known DDI records. To address the above limitations, we propose an attention-based cross domain graph neural network (ACDGNN) for DDI prediction, which considers the drug-related different entities and propagate information through cross domain operation. Different from the existing methods, ACDGNN not only considers rich information contained in drug-related biomedical entities in biological heterogeneous network, but also adopts cross-domain transformation to eliminate heterogeneity between different types of entities. ACDGNN can be used in the prediction of DDIs in both transductive and inductive setting. By conducting experiments on real-world dataset, we compare the performance of ACDGNN with several state-of-the-art methods. The experimental results show that ACDGNN can effectively predict DDIs and outperform the comparison models.


Assuntos
Redes Neurais de Computação , Humanos , Interações Medicamentosas
9.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38058185

RESUMO

Genomic prediction (GP) uses single nucleotide polymorphisms (SNPs) to establish associations between markers and phenotypes. Selection of early individuals by genomic estimated breeding value shortens the generation interval and speeds up the breeding process. Recently, methods based on deep learning (DL) have gained great attention in the field of GP. In this study, we explore the application of Transformer-based structures to GP and develop a novel deep-learning model named GPformer. GPformer obtains a global view by gleaning beneficial information from all relevant SNPs regardless of the physical distance between SNPs. Comprehensive experimental results on five different crop datasets show that GPformer outperforms ridge regression-based linear unbiased prediction (RR-BLUP), support vector regression (SVR), light gradient boosting machine (LightGBM) and deep neural network genomic prediction (DNNGP) in terms of mean absolute error, Pearson's correlation coefficient and the proposed metric consistent index. Furthermore, we introduce a knowledge-guided module (KGM) to extract genome-wide association studies-based information, which is fused into GPformer as prior knowledge. KGM is very flexible and can be plugged into any DL network. Ablation studies of KGM on three datasets illustrate the efficiency of KGM adequately. Moreover, GPformer is robust and stable to hyperparameters and can generalize to each phenotype of every dataset, which is suitable for practical application scenarios.


Assuntos
Estudo de Associação Genômica Ampla , Modelos Genéticos , Humanos , Genótipo , Teorema de Bayes , Genômica/métodos , Fenótipo , Polimorfismo de Nucleotídeo Único
10.
PLoS Pathog ; 19(5): e1011411, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37253057

RESUMO

Seneca virus A (SVA) is an emerging novel picornavirus that has recently been identified as the causative agent of many cases of porcine vesicular diseases in multiple countries. In addition to cleavage of viral polyprotein, the viral 3C protease (3Cpro) plays an important role in the regulation of several physiological processes involved in cellular antiviral responses by cleaving critical cellular proteins. Through a combination of crystallography, untargeted lipidomics, and immunoblotting, we identified the association of SVA 3Cpro with an endogenous phospholipid molecule, which binds to a unique region neighboring the proteolytic site of SVA 3Cpro. Our lipid-binding assays showed that SVA 3Cpro displayed preferred binding to cardiolipin (CL), followed by phosphoinositol-4-phosphate (PI4P) and sulfatide. Importantly, we found that the proteolytic activity of SVA 3Cpro was activated in the presence of the phospholipid, and the enzymatic activity is inhibited when the phospholipid-binding capacity decreased. Interestingly, in the wild-type SVA 3Cpro-substrate peptide structure, the cleavage residue cannot form a covalent binding to the catalytic cysteine residue to form the acyl-enzyme intermediate observed in several picornaviral 3Cpro structures. We observed a decrease in infectivity titers of SVA mutants harboring mutations that impaired the lipid-binding ability of 3Cpro, indicating a positive regulation of SVA infection capacity mediated by phospholipids. Our findings reveal a mutual regulation between the proteolytic activity and phospholipid-binding capacity in SVA 3Cpro, suggesting that endogenous phospholipid may function as an allosteric activator that regulate the enzyme's proteolytic activity during infection.


Assuntos
Cisteína Endopeptidases , Picornaviridae , Animais , Suínos , Cisteína Endopeptidases/metabolismo , Proteases Virais 3C/metabolismo , Peptídeo Hidrolases/metabolismo , Regulação Alostérica , Fosfolipídeos , Proteínas Virais/metabolismo
11.
Nucleic Acids Res ; 51(9): 4126-4147, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-37070173

RESUMO

Herein, we report the systematic investigation of stereopure phosphorothioate (PS) and phosphoryl guanidine (PN) linkages on siRNA-mediated silencing. The incorporation of appropriately positioned and configured stereopure PS and PN linkages to N-acetylgalactosamine (GalNAc)-conjugated siRNAs based on multiple targets (Ttr and HSD17B13) increased potency and durability of mRNA silencing in mouse hepatocytes in vivo compared with reference molecules based on clinically proven formats. The observation that the same modification pattern had beneficial effects on unrelated transcripts suggests that it may be generalizable. The effect of stereopure PN modification on silencing is modulated by 2'-ribose modifications in the vicinity, particularly on the nucleoside 3' to the linkage. These benefits corresponded with both an increase in thermal instability at the 5'-end of the antisense strand and improved Argonaute 2 (Ago2) loading. Application of one of our most effective designs to generate a GalNAc-siRNA targeting human HSD17B13 led to ∼80% silencing that persisted for at least 14 weeks after administration of a single 3 mg/kg subcutaneous dose in transgenic mice. The judicious use of stereopure PN linkages improved the silencing profile of GalNAc-siRNAs without disrupting endogenous RNA interference pathways and without elevating serum biomarkers for liver dysfunction, suggesting they may be suitable for therapeutic application.


Assuntos
Inativação Gênica , Interferência de RNA , RNA Mensageiro , Animais , Humanos , Camundongos , Camundongos Transgênicos , RNA Mensageiro/genética , RNA Interferente Pequeno/genética
12.
Proc Natl Acad Sci U S A ; 119(10): e2120379119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35238650

RESUMO

SignificanceThe detection of low-abundance molecular biomarkers is key to the liquid-biopsy-based disease diagnosis. Existing methods are limited by the affinity and specificity of recognition probes and the mass transportation of analyte molecules onto the sensor surfaces, resulting in insufficient sensitivity and long assay time. This work establishes a rapid and ultrasensitive approach by actively tuning binding kinetics and accelerating the mass transportation via nanoparticle micromanipulations. This is significant because it permits extremely sensitive measurements within clinically acceptable assay time. It is incubation-free, washing-free, and compatible with low- and high-affinity probes.


Assuntos
Imagem Individual de Molécula/métodos , Sítios de Ligação , Biomarcadores/metabolismo , Cinética , Limite de Detecção , Termodinâmica
13.
J Cell Mol Med ; 28(8): e18216, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38652219

RESUMO

We tried to elucidate the possible roles of maternal embryonic leucine pull chain kinase (MELK) in lung adenocarcinoma (LUAD) growth and metastasis. Differentially expressed genes in LUAD samples were analysed by the GEPIA database. Clinical tissue samples and cells were collected for MELK, EZH2 and LATS2 expression determination. Co-IP assay was used to verify the interaction between EZH2 and MELK; CHX tracking assay and ubiquitination assay detected the degradation of MELK on EZH2 ubiquitination. ChIP assay detected the enrichment of EZH2 and H3K27me3 on the LATS2 promoter region. LUAD cells were selected for in vitro validation, and the tumorigenic ability of LUAD cells was also observed in a transplantation tumour model of LUAD nude mice. MELK and EZH2 were highly expressed in LUAD samples, while LATS2 was lowly expressed. MELK interacted with EZH2 to inhibit its ubiquitination degradation; EZH2 elevated H3K27me3 modification in the LATS2 promoter to lower LATS2 expression. Silencing MELK or EZH2 or overexpressing LATS2 restrained LUAD cell proliferation and invasion, and facilitated their apoptosis. Silencing MELK or EZH2 or overexpressing LATS2 suppressed tumour formation in nude mice. This study demonstrated that MELK aggravated LUAD by upregulating EZH2 and downregulating LATS2.


Assuntos
Adenocarcinoma de Pulmão , Proliferação de Células , Proteína Potenciadora do Homólogo 2 de Zeste , Regulação Neoplásica da Expressão Gênica , Histonas , Neoplasias Pulmonares , Camundongos Nus , Proteínas Serina-Treonina Quinases , Proteínas Supressoras de Tumor , Ubiquitinação , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Animais , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Histonas/metabolismo , Camundongos , Proliferação de Células/genética , Metilação , Linhagem Celular Tumoral , Regiões Promotoras Genéticas/genética , Apoptose/genética , Feminino , Masculino
14.
Physiol Genomics ; 56(5): 367-383, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38073490

RESUMO

Members of the interleukin (IL) family are closely linked to cancer development and progression. However, research on the prognosis of colorectal cancer (CRC) related to IL is still lacking. This study investigated new CRC prognostic markers and offered new insights for CRC prognosis and treatment. CRC-related data and IL gene data were collected from public databases. Sample clustering was done with the NMF package to divide samples into different subtypes. Differential, enrichment, survival, and immune analyses were conducted on subtypes. A prognostic model was constructed using regression analysis. Drug sensitivity analysis was performed using GDSC database. Western blot analysis was performed to assess the effect of IL-7 on the JAK/STAT signaling pathway. Flow cytometry was used to examine the impact of IL-7 on CD8+ T cell apoptosis. Two CRC subtypes based on IL-associated genes were obtained. Cluster 1 had a higher survival rate than cluster 2, and they showed differences in some immune levels. The two clusters were mainly enriched in the JAK-STAT signaling pathway, T helper 17 cell differentiation, and the IL-17 signaling pathway. An 11-gene signature was built, and risk score was an independent prognosticator for CRC. The low-risk group showed a higher sensitivity to nine common targeted anticancer drugs. Western blot and flow cytometry results demonstrated that IL-7 could phosphorylate STAT5 and promote survival of CD8+ T cells. In conclusion, this study divided CRC samples into two IL-associated subtypes and obtained an 11-gene signature. In addition, targeted drugs that may improve the prognosis of patients with CRC were identified. These findings are of paramount importance for patient prognosis and CRC treatment.NEW & NOTEWORTHY We identified two clusters with significant survival differences in colorectal cancer (CRC) based on interleukin-related genes, constructed an 11-gene risk score model that can independently predict the prognosis of CRC, and explored some targeted drugs that may improve the prognosis of patients with CRC. The results of this study have important implications for the prognosis and treatment of CRC.

15.
J Biol Chem ; 299(7): 104895, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37290532

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is an enzyme that promotes the degradation of low-density lipoprotein receptors. It is involved in hyperlipidemia as well as other diseases, such as cancer and skin inflammation. However, the detailed mechanism for PCSK9 on ultraviolet B (UVB)-induced skin lesions was not clear. Thus, the role and possible action mechanism of PCSK9 in UVB-induced skin damage in mice were studied here using siRNA and a small molecule inhibitor (SBC110736) against PCSK9. Immunohistochemical staining revealed a significant increase in PCSK9 expression after UVB exposure, indicating the possible role of PCSK9 in UVB damage. Skin damage, increase in epidermal thickness, and keratinocyte hyperproliferation were significantly alleviated after treatment with SBC110736 or siRNA duplexes, compared with that in the UVB model group. Notably, UVB exposure triggered DNA damage in keratinocytes, whereas substantial interferon regulatory factor 3 (IRF3) activation was observed in macrophages. Pharmacologic inhibition of STING or cGAS knockout significantly reduced UVB-induced damage. In the co-culture system, supernatant from UVB-treated keratinocyte induced IRF3 activation in macrophages. This activation was inhibited with SBC110736 and by PCSK9 knockdown. Collectively, our findings reveal that PCSK9 plays a critical role in the crosstalk between damaged keratinocytes and STING activation in macrophages. The interruption of this crosstalk by PCSK9 inhibition may be a potential therapeutic strategy for UVB-induced skin damage.


Assuntos
Queratinócitos , Pró-Proteína Convertase 9 , Envelhecimento da Pele , Pele , Animais , Camundongos , Queratinócitos/enzimologia , Queratinócitos/efeitos da radiação , Macrófagos/metabolismo , Inibidores de PCSK9/farmacologia , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , RNA Interferente Pequeno/metabolismo , Pele/enzimologia , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos
16.
J Am Chem Soc ; 146(13): 9404-9412, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38504578

RESUMO

The catalytic and enantioselective construction of quaternary (all-carbon substituents) stereocenters poses a formidable challenge in organic synthesis due to the hindrance caused by steric factors. One conceptually viable and potentially versatile approach is the coupling of a C-C bond through an outer-sphere mechanism, accompanied by the realization of enantiocontrol through cooperative catalysis; however, examples of such processes are yet to be identified. Herein, we present such a method for creating different compounds with quaternary stereocenters by photoredox/Fe/chiral primary amine triple catalysis. This approach facilitates the connection of an unactivated alkyl source with a tertiary alkyl moiety, which is also rare. The scalable process exhibits mild conditions, does not necessitate the use of a base, and possesses a good functional-group tolerance. Preliminary investigations into the underlying mechanisms have provided valuable insights into the reaction pathway.

17.
J Am Chem Soc ; 146(6): 3890-3899, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38294957

RESUMO

Topological insulators offer significant potential to revolutionize diverse fields driven by nontrivial manifestations of their topological electronic band structures. However, the realization of superior integration between exotic topological states and superconductivity for practical applications remains a challenge, necessitating a profound understanding of intricate mechanisms. Here, we report experimental observations for a novel superconducting phase in the pressurized second-order topological insulator candidate Ta2Pd3Te5, and the high-pressure phase maintains its original ambient pressure lattice symmetry up to 45 GPa. Our in situ high-pressure synchrotron X-ray diffraction, electrical transport, infrared reflectance, and Raman spectroscopy measurements, in combination with rigorous theoretical calculations, provide compelling evidence for the association between the superconducting behavior and the densified phase. The electronic state change around 20 GPa was found to modify the topology of the Fermi surface directly, which synergistically fosters the emergence of robust superconductivity. In-depth comprehension of the fascinating properties exhibited by the compressed Ta2Pd3Te5 phase is achieved, highlighting the extraordinary potential of topological insulators for exploring and investigating high-performance electronic advanced devices under extreme conditions.

18.
Int J Cancer ; 155(4): 710-718, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608177

RESUMO

Thymic carcinoma (TC) is a rare malignant tumor with a poor prognosis, and there is currently limited data on the use of immunotherapy in patients with unresectable TC. In this study, data of patients with unresectable TC diagnosed from January 2017 were retrospectively collected from multiple centers. Treatment response, progression-free survival (PFS), overall survival (OS), survival-independent prognostic factor, and adverse events (AEs) were further analyzed. As a result, a total of 93 patients with unresectable TC were enrolled, of which 54 received first-line chemotherapy, and 39 received chemotherapy plus immune checkpoint inhibitors (ICIs). The objective response rate was 50% (27/54) in the chemotherapy group and 76.9% (30/39) in the chemotherapy plus ICIs group. The chemotherapy plus ICIs group achieved significant median PFS benefit (8.8 vs. 34.9 months, p < .001) and median OS benefit (41.8 months vs. not reached, p = .025). Multivariate analysis showed that ICIs and local therapy were independent prognostic factors for PFS. In addition, 17 patients developed immune-related AEs (IRAEs), of which 15 (38.5%) had Grade 1 or 2 IRAEs and 2 (5.1%) had Grade 3 IRAEs in the chemotherapy plus ICIs group. In conclusion, the efficacy of chemotherapy plus ICIs is superior to chemotherapy, and the adverse effects are manageable in patients with unresectable TC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Inibidores de Checkpoint Imunológico , Timoma , Neoplasias do Timo , Humanos , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/administração & dosagem , Idoso , Neoplasias do Timo/tratamento farmacológico , Neoplasias do Timo/mortalidade , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Timoma/tratamento farmacológico , Timoma/mortalidade , Prognóstico , Intervalo Livre de Progressão
19.
Am J Physiol Gastrointest Liver Physiol ; 326(4): G426-G437, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38290991

RESUMO

This study aims to investigate the role and molecular mechanism of anthocyanin in improving liver fibrosis through ferroptosis, providing a basis for drug development and targeted therapy. In this study, a mouse model of liver fibrosis was established using CCl4, and the anthocyanin treatment groups were administered 100 mg/kg anthocyanin daily via gavage. Furthermore, real-time fluorescent quantitative PCR (qRT-PCR), Western blotting (WB), and enzyme-linked immunosorbent assay were used to assess liver fibrosis indicators and liver injury markers. Histopathological methods were used to confirm the morphology of liver injury in different treatment groups. The effects of anthocyanins on ferroptosis markers, NCOA4 and FTH1 expression, were examined through qRT-PCR, WB, and Co-IP. Confocal microscopy was used to validate the colocalization of ferritin and lysosomes. A differential expression model of TRIM7 was constructed to verify its impact on the progression of liver fibrosis. The present study demonstrates the hepatoprotective effects of anthocyanins in liver fibrosis, highlighting their ability to enhance hepatic stellate cell (HSC) ferroptosis and regulate ferritin autophagy. Moreover, TRIM7 is identified as a key mediator of anthocyanin-induced regulation of hepatic stellate cells activation for liver fibrosis treatment through modulation of ferroautophagy. Mechanistic investigations further reveal that TRIM7 exerts its influence on the process of ferroautophagy by controlling NCOA4 ubiquitination. Our study discovered that anthocyanins could improve liver fibrosis by regulating NCOA4 ubiquitination through TRIM7, thereby affecting hepatic stellate cells' ferroptosis levels.NEW & NOTEWORTHY This was the first study to demonstrate that anthocyanins can improve the progression of liver fibrosis by promoting hepatic stellate cell (HSC) ferroptosis. Anthocyanins could affect the content of Fe2+ by promoting ferroautophagy in HSCs, thereby promoting the level of ferroptosis. This study demonstrates for the first time that anthocyanins can inhibit the expression of TRIM7 and then affect the ubiquitination of NCOA4 to regulate the level of ferritin autophagy and ferroptosis.


Assuntos
Antocianinas , Mirtilos Azuis (Planta) , Ferroptose , Cirrose Hepática , Animais , Camundongos , Antocianinas/farmacologia , Antocianinas/metabolismo , Antocianinas/uso terapêutico , Mirtilos Azuis (Planta)/química , Ferritinas , Ferroptose/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Ubiquitinação/efeitos dos fármacos , Coativadores de Receptor Nuclear/efeitos dos fármacos , Coativadores de Receptor Nuclear/metabolismo , Proteínas com Motivo Tripartido/efeitos dos fármacos , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo
20.
J Mol Evol ; 92(1): 42-60, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38280051

RESUMO

Fig wasps (Agaonidae; Hymenoptera) are the only pollinating insects of fig trees (Ficus; Moraceae), forming the most closely and highly specific mutualism with the host. We used transcriptome sequences of 25 fig wasps from six genera to explore the evolution of key molecular components of fig wasp chemosensory genes: odorant-binding proteins (OBPs) and chemosensory proteins (CSPs). We identified a total 321 OBPs and 240 CSPs, with each species recording from 6 to 27 OBP genes and 6-19 CSP genes. 318 OBP genes are clustered into 17 orthologous groups and can be divided into two groups: PBP sensitive to pheromone and GOBP sensitive to general odor molecules, such as alcohols, esters, acids, ketones, and terpenoids. 240 CSP genes are clustered into 12 orthologous groups, which can be divided into three major groups and have functions, such as olfactory, tissue formation and/or regeneration, developmental, and some specific and unknown function. The gene sequences of most orthologous groups vary greatly among species and are consistent with the phylogenetic relationships between fig wasps. Strong purifying selection of both OBP and CSP genes was detected, as shown by low ω values. A positive selection was detected in one locus in CSP1. In conclusion, the evolution of chemosensory proteins OBPs and CSPs in fig wasps is relatively conservative, and they play an indispensable role in the life activities of fig wasps. Our results provide a starting point for understanding the molecular basis of the chemosensory systems of fig wasps.


Assuntos
Ficus , Vespas , Animais , Filogenia , Vespas/genética , Ficus/genética , Odorantes , Simbiose
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