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1.
Cell ; 186(7): 1337-1351.e20, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36870332

RESUMO

Leaf-feeding insects trigger high-amplitude, defense-inducing electrical signals called slow wave potentials (SWPs). These signals are thought to be triggered by the long-distance transport of low molecular mass elicitors termed Ricca's factors. We sought mediators of leaf-to-leaf electrical signaling in Arabidopsis thaliana and identified them as ß-THIOGLUCOSIDE GLUCOHYDROLASE 1 and 2 (TGG1 and TGG2). SWP propagation from insect feeding sites was strongly attenuated in tgg1 tgg2 mutants and wound-response cytosolic Ca2+ increases were reduced in these plants. Recombinant TGG1 fed into the xylem elicited wild-type-like membrane depolarization and Ca2+ transients. Moreover, TGGs catalyze the deglucosidation of glucosinolates. Metabolite profiling revealed rapid wound-induced breakdown of aliphatic glucosinolates in primary veins. Using in vivo chemical trapping, we found evidence for roles of short-lived aglycone intermediates generated by glucosinolate hydrolysis in SWP membrane depolarization. Our findings reveal a mechanism whereby organ-to-organ protein transport plays a major role in electrical signaling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Animais , Glicosídeo Hidrolases/metabolismo , Glucosinolatos/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Insetos
2.
Cell ; 182(5): 1271-1283.e16, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32795413

RESUMO

There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.


Assuntos
RNA Mensageiro/genética , RNA Viral/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Vacinas contra COVID-19 , Chlorocebus aethiops , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Feminino , Células HEK293 , Células HeLa , Humanos , Imunogenicidade da Vacina , Injeções Intramusculares , Macaca fascicularis , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/química , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Th1/imunologia , Potência de Vacina , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Células Vero , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
3.
Immunity ; 52(6): 971-977.e3, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32413330

RESUMO

The World Health Organization has declared SARS-CoV-2 virus outbreak a worldwide pandemic. However, there is very limited understanding on the immune responses, especially adaptive immune responses to SARS-CoV-2 infection. Here, we collected blood from COVID-19 patients who have recently become virus-free, and therefore were discharged, and detected SARS-CoV-2-specific humoral and cellular immunity in eight newly discharged patients. Follow-up analysis on another cohort of six patients 2 weeks post discharge also revealed high titers of immunoglobulin G (IgG) antibodies. In all 14 patients tested, 13 displayed serum-neutralizing activities in a pseudotype entry assay. Notably, there was a strong correlation between neutralization antibody titers and the numbers of virus-specific T cells. Our work provides a basis for further analysis of protective immunity to SARS-CoV-2, and understanding the pathogenesis of COVID-19, especially in the severe cases. It also has implications in developing an effective vaccine to SARS-CoV-2 infection.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/imunologia , Imunidade Celular , Imunidade Humoral , Pneumonia Viral/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , COVID-19 , Convalescença , Infecções por Coronavirus/sangue , Infecções por Coronavirus/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/patologia , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/imunologia
4.
Immunity ; 46(6): 992-1004.e5, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28636969

RESUMO

RNA interference (RNAi) functions as a potent antiviral immunity in plants and invertebrates; however, whether RNAi plays antiviral roles in mammals remains unclear. Here, using human enterovirus 71 (HEV71) as a model, we showed HEV71 3A protein as an authentic viral suppressor of RNAi during viral infection. When the 3A-mediated RNAi suppression was impaired, the mutant HEV71 readily triggered the production of abundant HEV71-derived small RNAs with canonical siRNA properties in cells and mice. These virus-derived siRNAs were produced from viral dsRNA replicative intermediates in a Dicer-dependent manner and loaded into AGO, and they were fully active in degrading cognate viral RNAs. Recombinant HEV71 deficient in 3A-mediated RNAi suppression was significantly restricted in human somatic cells and mice, whereas Dicer deficiency rescued HEV71 infection independently of type I interferon response. Thus, RNAi can function as an antiviral immunity, which is induced and suppressed by a human virus, in mammals.


Assuntos
Enterovirus Humano A/imunologia , Infecções por Enterovirus/imunologia , Imunidade , Interferência de RNA , RNA Viral/imunologia , Animais , Proteínas Argonautas/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Enterovirus Humano A/genética , Células HEK293 , Humanos , Mamíferos , Camundongos , Camundongos da Linhagem 129 , Camundongos Knockout , Mutação/genética , Ribonuclease III/metabolismo , Proteínas Virais/imunologia
5.
Immunity ; 46(3): 446-456, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28314593

RESUMO

Zika virus (ZIKV) has become a public health threat due to its global transmission and link to severe congenital disorders. The host immune responses to ZIKV infection have not been fully elucidated, and effective therapeutics are not currently available. Herein, we demonstrated that cholesterol-25-hydroxylase (CH25H) was induced in response to ZIKV infection and that its enzymatic product, 25-hydroxycholesterol (25HC), was a critical mediator of host protection against ZIKV. Synthetic 25HC addition inhibited ZIKV infection in vitro by blocking viral entry, and treatment with 25HC reduced viremia and conferred protection against ZIKV in mice and rhesus macaques. 25HC suppressed ZIKV infection and reduced tissue damage in human cortical organoids and the embryonic brain of the ZIKV-induced mouse microcephaly model. Our findings highlight the protective role of CH25H during ZIKV infection and the potential use of 25HC as a natural antiviral agent to combat ZIKV infection and prevent ZIKV-associated outcomes, such as microcephaly.


Assuntos
Antivirais/farmacologia , Hidroxicolesteróis/farmacologia , Microcefalia/virologia , Infecção por Zika virus/complicações , Animais , Encéfalo/efeitos dos fármacos , Modelos Animais de Doenças , Imunofluorescência , Humanos , Macaca mulatta , Camundongos , Microscopia Confocal , Internalização do Vírus/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Zika virus/fisiologia
7.
Plant Physiol ; 194(2): 1091-1103, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-37925642

RESUMO

Ricca assays allow the direct introduction of compounds extracted from plants or the organisms that attack them into the leaf vasculature. Using chromatographic fractionation of Arabidopsis (Arabidopsis thaliana) leaf extracts, we found glutamate was the most active low mass elicitor of membrane depolarization. However, other known elicitors of membrane depolarization are generated in the wound response. These include unstable aglycones generated by glucosinolate (GSL) breakdown. None of the aglycone-derived GSL-breakdown products, including nitriles and isothiocyanates, that we tested using Ricca assays triggered electrical activity. Instead, we found that glutathione and the GSL-derived compound sulforaphane glutathione triggered membrane depolarizations. These findings identify a potential link between GSL breakdown and glutathione in the generation of membrane depolarizing signals. Noting that the chromatographic fractionation of plant extracts can dilute or exchange ions, we found that Cl- caused glutamate receptor-like3.3-dependent membrane depolarizations. In summary, we show that, in addition to glutamate, glutathione derivatives as well as chloride ions will need to be considered as potential elicitors of wound-response membrane potential change. Finally, by introducing aphid (Brevicoryne brassicae) extracts or the flagellin-derived peptide flg22 into the leaf vasculature we extend the use of Ricca assays for the exploration of insect/plant and bacteria/plant interactions.


Assuntos
Arabidopsis , Cloretos , Cloretos/metabolismo , Arabidopsis/metabolismo , Glutationa/farmacologia , Glutationa/metabolismo , Xilema , Glutamatos/metabolismo
8.
Stroke ; 55(9): 2221-2230, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39082144

RESUMO

BACKGROUND: Cardiocerebral infarction (CCI), which is concomitant with acute myocardial infarction (AMI) and acute ischemic stroke (AIS), is a rare but severe presentation. However, there are few data on CCI, and the treatment options are uncertain. We investigated the characteristics and outcomes of CCI compared with AMI or AIS alone. METHODS: We performed a retrospective cohort study of 120 531 patients with AMI and AIS from the national stroke and AMI registries in Singapore. Patients were categorized into AMI only, AIS only, synchronous CCI (same-day), and metachronous CCI (within 1 week). The primary outcome was all-cause mortality, and the secondary outcome was cardiovascular mortality. The mortality risks were compared using Cox regression. Multivariable models were adjusted for baseline demographics, clinical variables, and treatment for AMI or AIS. RESULTS: Of 127 919 patients identified, 120 531 (94.2%) were included; 74 219 (61.6%) patients had AMI only, 44 721 (37.1%) had AIS only, 625 (0.5%) had synchronous CCI, and 966 (0.8%) had metachronous CCI. The mean age was 67.7 (SD, 14.0) years. Synchronous and metachronous CCI had a higher risk of 30-day mortality (synchronous: adjusted HR [aHR], 2.41 [95% CI, 1.77-3.28]; metachronous: aHR, 2.80 [95% CI, 2.11-3.73]) than AMI only and AIS only (synchronous: aHR, 2.90 [95% CI, 1.87-4.51]; metachronous: aHR, 4.36 [95% CI, 3.03-6.27]). The risk of cardiovascular mortality was higher in synchronous and metachronous CCI than AMI (synchronous: aHR, 3.03 [95% CI, 2.15-4.28]; metachronous: aHR, 3.41 [95% CI, 2.50-4.65]) or AIS only (synchronous: aHR, 2.58 [95% CI, 1.52-4.36]; metachronous: aHR, 4.52 [95% CI, 2.95-6.92]). In synchronous CCI, AMI was less likely to be managed with PCI and secondary prevention medications (P<0.001) compared with AMI only. CONCLUSIONS: Synchronous CCI occurred in 1 in 200 cases of AIS and AMI. Synchronous and metachronous CCI had higher mortality than AMI or AIS alone.


Assuntos
Infarto do Miocárdio , Sistema de Registros , Humanos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/epidemiologia , Estudos Retrospectivos , Incidência , Singapura/epidemiologia , Idoso de 80 Anos ou mais , Estudos de Coortes , AVC Isquêmico/epidemiologia , AVC Isquêmico/mortalidade , AVC Isquêmico/terapia
9.
J Am Chem Soc ; 146(19): 13546-13557, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38690842

RESUMO

Glycidic esters represent pivotal constituents in synthetic chemistry, offering enhanced versatility for tailoring toward a diverse array of molecular targets in comparison with simple epoxides. While considerable progress has been made in the asymmetric synthesis of trans- and trisubstituted glycidic esters, achieving enantioselective preparation of cis-glycidic esters has remained a long-standing challenge. Here, we demonstrate a selectivity-predictable modular platform for the asymmetric synthesis of cis-glycidic esters via a novel dinuclear (salen)titanium(III)-catalyzed radical-type kinetic resolution (KR) approach. This radical KR protocol operates under mild conditions and demonstrates a wide substrate scope, facilitating the synthesis of alkyl- and aryl-substituted cis-glycidic esters with high levels of regioselectivity and enantioselectivity, along with hydroxy ester byproducts representing synthetically valuable motifs as well. This study presents a unique exploration of radical-type KR applied to epoxides, effectively overcoming the steric challenges inherent in conventional nucleophilic-type methodologies typically employed in epoxide chemistry.

10.
J Am Chem Soc ; 146(37): 25445-25450, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39235150

RESUMO

To date, it remains challenging to precisely and efficiently construct structurally intriguing polycarbocycles with densely packed stereocenters in organic synthesis. Niduterpenoid B, a naturally occurring ERα inhibitor, exemplifies this complexity with its intricate polycyclic network comprising 5 cyclopentane and 1 cyclopropane rings, featuring 13 contiguous stereocenters, including 4 all-carbon quaternary centers. In this work, we describe the first total synthesis of niduterpenoid B using a structural reorganization strategy. Key features include the following: (1) an efficient methoxy-controlled cascade reaction that precisely forges a highly functionalized tetraquinane (A-D rings) bearing sterically hindered contiguous quaternary stereocenters; (2) a rhodium-catalyzed [1 + 2] cycloaddition that facilitates the construction of a strained 3/5 bicycle (E-F rings) angularly fused with ring D.

11.
J Am Chem Soc ; 146(28): 18841-18847, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38975938

RESUMO

An asymmetric intramolecular spiro-amination to high steric hindering α-C-H bond of 1,3-dicarbonyl via nitrene transfer using inactive aryl azides has been carried out by developing a novel Cp*Ir(III)-SPDO (spiro-pyrrolidine oxazoline) catalyst, thereby enabling the first successful construction of structurally rigid spiro-quaternary indolinone cores with moderate to high yields and excellent enantioselectivities. DFT computations support the presence of double bridging H-F bonds between [SbF6]- and both the ligand and substrate, which favors the plane-differentiation of the enol π-bond for nitrenoid attacking. These findings open up numerous opportunities for the development of new asymmetric nitrene transfer systems.

12.
Clin Immunol ; 261: 109925, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38310993

RESUMO

BACKGROUND: Inflammatory factors are being recognized as critical modulators of host antitumor immunity in liver cancer. We have previously shown that tumor cell-released LC3B positive extracellular vesicles (LC3B+ EVs) are responsible for malignant progression by dampening antitumor immunity. However, the relationship between LC3B+ EVs and inflammatory factors in the regulation of the liver cancer microenvironment remains unclear. METHODS: Flow cytometry analyses were performed to examine the panel of 12 cytokines, the main source of positive cytokines, and plasma LC3B+ EVs carrying HSP90α in peripheral blood of liver cancer patients. We correlated the levels of plasma IL-6, IL-8 with LC3B+ EVs carrying HSP90α and with prognosis. In vitro culture of healthy donor leukocytes with liver cancer-derived LC3B+ EVs was performed to evaluate the potential effect of blocking HSP90α, IL-6 or IL-8 alone or in combination with PD-1 inhibitor on CD8+ T cell function. We also investigated the potential associations of MAP1LC3B, HSP90AA1, IL6 or IL8 with immunotherapy efficacy using the TCGA databases. RESULTS: In liver cancer patients, plasma IL-6 and IL-8 levels were significantly higher than in healthy controls and associated with poor clinical outcome. In peripheral blood, levels of plasma LC3B+ EVs carrying HSP90α were significantly elevated in HCC patients and positively associated with IL-6 and IL-8 levels, which are predominantly secreted by monocytes and neutrophils. Moreover, LC3B+ EVs from human liver cancer cells promoted the secretion of IL-6 and IL-8 by leukocytes through HSP90α. Besides, we show that the cytokines IL-6 and IL-8 secreted by LC3B+ EVs-induced leukocytes were involved in the inhibition of CD8+ T-cell function, while blockade of the HSP90α on the LC3B+ EVs, IL-6, or IL-8 could enhance anti-PD-1-induced T cell reinvigoration. Finally, patients who received anti-PD-1/PD-L1 immunotherapy with high MAP1LC3B, HSP90AA1, IL6, or IL8 expression had a lower immunotherapy efficacy. CONCLUSIONS: Our data suggest that liver cancer-derived LC3B+ EVs promote a pro-oncogenic inflammatory microenvironment by carrying membrane-bound HSP90α. Targeting HSP90α on the LC3B+ EVs, IL-6, or IL-8 may synergize with anti-PD-1 treatment to enhance the CD8+ T-cell functions, which may provide novel combination strategies in the clinic for the treatment of liver cancer.


Assuntos
Carcinoma Hepatocelular , Vesículas Extracelulares , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Microambiente Tumoral , Citocinas/metabolismo , Imunoterapia , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia
13.
Small ; : e2405946, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39246162

RESUMO

Under large current densities, the excessive hydroxide ion (OH) consumption hampers alkaline water splitting involving the oxygen evolution reaction (OER). High OH concentration (≈30 wt.%) is often used to enhance the catalytic activity of OER, but it also leads to higher corrosion in practical systems. To achieve higher catalytic activity in low OH concentration, catalysts on magnetic frame (CMF) are built to utilize the local magnetic convection induced from the host frame's magnetic field distributions. This way, a higher reaction rate can be achieved in relatively lower OH concentrations. A CMF model system with catalytically active CoFeOx nanograins grown on the magnetic Ni foam is demonstrated. The OER current of CoFeOx@NF receives ≈90% enhancement under 400 mT (900 mA cm-2 at 1.65 V) compared to that in zero field, and exhibits remarkable durability over 120 h. As a demonstration, the water-splitting performance sees a maximum 45% magnetic enhancement under 400 mT in 1 m KOH (700 mA cm-2 at 2.4 V), equivalent to the concentration enhancement of the same electrode in a more corrosive 2 m KOH electrolyte. Therefore, the catalyst-on-magnetic-frame strategy can make efficient use of the catalysts and achieve higher catalytic activity in low OH concentration by harvesting local magnetic convection.

14.
Plant Biotechnol J ; 22(11): 3121-3134, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39021281

RESUMO

Cis-regulatory elements (CREs) are integral to the spatiotemporal and quantitative expression dynamics of target genes, thus directly influencing phenotypic variation and evolution. However, many of these CREs become highly susceptible to transcriptional silencing when in a transgenic state, particularly when organised as tandem repeats. We investigated the mechanism of this phenomenon and found that three of the six selected flower-specific CREs were prone to transcriptional silencing when in a transgenic context. We determined that this silencing was caused by the ectopic expression of non-coding RNAs (ncRNAs), which were processed into 24-nt small interfering RNAs (siRNAs) that drove RNA-directed DNA methylation (RdDM). Detailed analyses revealed that aberrant ncRNA transcription within the AGAMOUS enhancer (AGe) in a transgenic context was significantly enhanced by an adjacent CaMV35S enhancer (35Se). This particular enhancer is known to mis-activate the regulatory activities of various CREs, including the AGe. Furthermore, an insertion of 35Se approximately 3.5 kb upstream of the AGe in its genomic locus also resulted in the ectopic induction of ncRNA/siRNA production and de novo methylation specifically in the AGe, but not other regions, as well as the production of mutant flowers. This confirmed that interactions between the 35Se and AGe can induce RdDM activity in both genomic and transgenic states. These findings highlight a novel epigenetic role for CRE-CRE interactions in plants, shedding light on the underlying forces driving hypermethylation in transgenes, duplicate genes/enhancers, and repetitive transposons, in which interactions between CREs are inevitable.


Assuntos
Metilação de DNA , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , RNA não Traduzido , Metilação de DNA/genética , Elementos Facilitadores Genéticos/genética , Plantas Geneticamente Modificadas/genética , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Inativação Gênica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Flores/genética , Arabidopsis/genética
15.
Ann Surg Oncol ; 31(9): 6049-6064, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38847986

RESUMO

BACKGROUND: The objective of this meta-analysis was to assess the association of sarcopenia defined on computed tomography (CT) head and neck with survival in head and neck cancer patients. METHODS: Following a PROSPERO-registered protocol, two blinded reviewers extracted data and evaluated the quality of the included studies using the Quality In Prognostic Studies (QUIPS) tool, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework. A meta-analysis was conducted using maximally adjusted hazard ratios (HRs) with the random-effects model. Heterogeneity was measured using the I2 statistic and was investigated using meta-regression and subgroup analyses where appropriate. RESULTS: From 37 studies (11,181 participants), sarcopenia was associated with poorer overall survival (HR 2.11, 95% confidence interval [CI] 1.81-2.45; p < 0.01), disease-free survival (HR 1.76, 95% CI 1.38-2.24; p < 0.01), disease-specific survival (HR 2.65, 95% CI 1.80-3.90; p < 0.01), progression-free survival (HR 2.24, 95% CI 1.21-4.13; p < 0.01) and increased chemotherapy or radiotherapy toxicity (risk ratio 2.28, 95% CI 1.31-3.95; p < 0.01). The observed association between sarcopenia and overall survival remained significant across different locations of cancer, treatment modality, tumor stages and geographical region, and did not differ between univariate and multivariate HRs. Statistically significant correlations were observed between the C3 and L3 cross-sectional area, skeletal muscle mass, and skeletal muscle index. CONCLUSIONS: Among patients with head and neck cancers, CT-defined sarcopenia was consistently associated with poorer survival and greater toxicity.


Assuntos
Neoplasias de Cabeça e Pescoço , Sarcopenia , Sarcopenia/mortalidade , Humanos , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/complicações , Neoplasias de Cabeça e Pescoço/patologia , Taxa de Sobrevida , Prognóstico , Prevalência
16.
Cytokine ; 177: 156555, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38387232

RESUMO

Interferon-alpha (IFN-α) is widely used in the clinical treatment of patients with chronic hepatitis B and hepatocellular carcinoma (HCC). However, high levels of CXCL8 are associated with resistance to IFN-α therapy and poorer prognosis in advanced cancers. In this study, we investigated whether IFN-α could directly induce the production of CXCL8 in HCC cells and whether CXCL8 could antagonize the antitumor activity of IFN-α. We found that IFN-α not only upregulated the expression of the inducible genes CXCL9, CXCL10, CXCL11 and PD-L1, but also significantly stimulated CXCL8 secretion in HCC cells. Mechanically, IFN-α induces CXCL8 expression by activating the AKT and JNK pathways. In addition, our results demonstrate that IFN-α exposure significantly increases the differentiation of HCC stem cells, but this effect is reversed by the addition of the CXCL8 receptor CXCR1/2 inhibitor Reparixin and STAT3 inhibitor Stattic. Besides, our study reveals that the cytokine CXCL8 secreted by IFN-α-induced HCC cells inhibits T-cell function. Conversely, inhibition of CXCL8 promotes TNF-α and IFN-γ secretion by T cells. Finally, liver cancer patients who received anti-PD-1/PD-L1 immunotherapy with high CXCL8 expression had a lower immunotherapy efficacy. Overall, our findings clarify that IFN-α triggers immunosuppression and cancer stem cell differentiation in hepatocellular carcinoma by upregulating CXCL8 secretion. This discovery provides a novel approach to enhance the effectiveness of HCC treatment in the future.


Assuntos
Carcinoma Hepatocelular , Interferon-alfa , Interleucina-8 , Neoplasias Hepáticas , Humanos , Antígeno B7-H1/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Diferenciação Celular , Terapia de Imunossupressão , Interferon-alfa/farmacologia , Interferon gama/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Interleucina-8/metabolismo
17.
Cancer Cell Int ; 24(1): 311, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256838

RESUMO

BACKGROUND: Currently, there are no optimal biomarkers available for distinguishing patients who will respond to immune checkpoint inhibitors (ICIs) therapies. Consequently, the exploration of novel biomarkers that can predict responsiveness to ICIs is crucial in the field of immunotherapy. METHODS: We estimated the proportions of 22 immune cell components in 10 cancer types (6,128 tumors) using the CIBERSORT algorithm, and further classified patients based on their tumor immune cell proportions in a pan-cancer setting using k-means clustering. Differentially expressed immune genes between the patient subgroups were identified, and potential predictive biomarkers for ICIs were explored. Finally, the predictive value of the identified biomarkers was verified in patients with urothelial carcinoma (UC) and esophageal squamous cell carcinoma (ESCC) who received ICIs. RESULTS: Our study identified two subgroups of patients with distinct immune infiltrating phenotypes and differing clinical outcomes. The patient subgroup with improved outcomes displayed tumors enriched with genes related to immune response regulation and pathway activation. Furthermore, CCL5 and CSF2 were identified as immune-related hub-genes and were found to be prognostic in a pan-cancer setting. Importantly, UC and ESCC patients with high expression of CCL5 and low expression of CSF2 responded better to ICIs. CONCLUSION: We demonstrated CCL5 and CSF2 as potential novel biomarkers for predicting the response to ICIs in patients with UC and ESCC. The predictive value of these biomarkers in other cancer types warrants further evaluation in future studies.

18.
Artigo em Inglês | MEDLINE | ID: mdl-39043567

RESUMO

BACKGROUND: The efficacy of endovascular treatment (EVT) in acute ischaemic stroke due to distal medium vessel occlusion (DMVO) remains uncertain. Our study aimed to evaluate the safety and efficacy of EVT compared with the best medical management (BMM) in DMVO. METHODS: In this prospectively collected, retrospectively reviewed, multicentre cohort study, we analysed data from the Multicentre Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy registry. Patients with acute ischaemic stroke due to DMVO in the M2, M3 and M4 segments who underwent EVT or received BMM were included. Primary outcome measures comprised 10 co-primary endpoints, including functional independence (mRS 0-2), excellent outcome (mRS 0-1), mortality (mRS 6) and haemorrhagic complications. Propensity score matching was employed to balance the cohorts. RESULTS: Among 2125 patients included in the primary analysis, 1713 received EVT and 412 received BMM. After propensity score matching, each group comprised 391 patients. At 90 days, no significant difference was observed in achieving mRS 0-2 between EVT and BMM (adjusted OR 1.00, 95% CI 0.67 to 1.50, p>0.99). However, EVT was associated with higher rates of symptomatic intracerebral haemorrhage (8.4% vs 3.0%, adjusted OR 3.56, 95% CI 1.69 to 7.48, p<0.001) and any intracranial haemorrhage (37% vs 19%, adjusted OR 2.61, 95% CI 1.81 to 3.78, p<0.001). Mortality rates were similar between groups (13% in both, adjusted OR 1.48, 95% CI 0.87 to 2.51, p=0.15). CONCLUSION: Our findings suggest that while EVT does not significantly improve functional outcomes compared with BMM in DMVO, it is associated with higher risks of haemorrhagic complications. These results support a cautious approach to the use of EVT in DMVO and highlight the need for further prospective randomised trials to refine treatment strategies.

19.
Theor Appl Genet ; 137(8): 193, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073628

RESUMO

KEY MESSAGE: A total of 65 SNPs associated with resistance to tan spot and septoria nodorum blotch were identified in a panel of 180 cultivated emmer accessions through association mapping Tan spot and septoria nodorum blotch (SNB) are foliar diseases caused by the respective fungal pathogens Pyrenophora tritici-repentis and Parastagonospora nodorum that affect global wheat production. To find new sources of resistance, we evaluated a panel of 180 cultivated emmer wheat (Triticum turgidum ssp. dicoccum) accessions for reactions to four P. tritici-repentis isolates Pti2, 86-124, 331-9 and DW5, two P. nodorum isolate, Sn4 and Sn2000, and four necrotrophic effectors (NEs) produced by the pathogens. About 8-36% of the accessions exhibited resistance to the four P. tritici-repentis isolates, with five accessions demonstrating resistance to all isolates. For SNB, 64% accessions showed resistance to Sn4, 43% to Sn2000 and 36% to both isolates, with Spain (11% accessions) as the most common origin of resistance. To understand the genetic basis of resistance, association mapping was performed using SNP (single nucleotide polymorphism) markers generated by genotype-by-sequencing and the 9 K SNP Infinium array. A total of 46 SNPs were significantly associated with tan spot and 19 SNPs with SNB resistance or susceptibility. Six trait loci on chromosome arms 1BL, 3BL, 4AL (2), 6BL and 7AL conferred resistance to two or more isolates. Known NE sensitivity genes for disease development were undetected except Snn5 for Sn2000, suggesting novel genetic factors are controlling host-pathogen interaction in cultivated emmer. The emmer accessions with the highest levels of resistance to the six pathogen isolates (e.g., CItr 14133-1, PI 94634-1 and PI 377672) could serve as donors for tan spot and SNB resistance in wheat breeding programs.


Assuntos
Ascomicetos , Mapeamento Cromossômico , Resistência à Doença , Doenças das Plantas , Polimorfismo de Nucleotídeo Único , Triticum , Triticum/microbiologia , Triticum/genética , Triticum/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Resistência à Doença/genética , Ascomicetos/patogenicidade , Ascomicetos/fisiologia , Fenótipo , Genótipo , Locos de Características Quantitativas , Marcadores Genéticos , Estudos de Associação Genética
20.
Liver Int ; 44(10): 2700-2713, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39037193

RESUMO

BACKGROUND AND AIMS: Distinctive gut microbial profiles have been observed between patients with Wilson disease (WD) and healthy individuals. Despite this, the exact relationship and influence of gut microbiota on the advancement of WD-related liver damage remain ambiguous. This research seeks to clarify the gut microbiota characteristics in both human patients and mouse models of WD, as well as their impact on liver injury. METHODS: Gut microbial features in healthy individuals, patients with WD, healthy mice and mice with early- and late-stage WD were analysed using 16S rRNA gene sequencing. Additionally, WD-afflicted mice underwent treatment with either an antibiotic cocktail (with normal saline as a control) or healthy microbiota (using disease microbiota as a control). The study assessed gut microbiota composition, hepatic transcriptome profiles, liver copper concentrations and hepatic pathological injuries. RESULTS: Patients with hepatic WD and mice with WD-related liver injury displayed altered gut microbiota composition, notably with a significant reduction in Lactobacillus abundance. Additionally, the abundances of several gut genera, including Lactobacillus, Veillonella and Eubacterium coprostanoligenes, showed significant correlations with the severity of liver injury in patients with WD. In WD mice, antibiotic treatment or transplantation of healthy microbiota altered the gut microbial structure, increased Lactobacillus abundance and modified the hepatic transcriptional profile. These interventions resulted in reduced hepatic copper concentration and alleviation of WD-related liver injury. CONCLUSIONS: Individuals and mice with pronounced WD-related liver injury exhibited shifts in gut microbial composition. Regulating gut microbiota through healthy microbiota transplantation emerges as a promising therapeutic approach for treating WD-related liver injury.


Assuntos
Modelos Animais de Doenças , Microbioma Gastrointestinal , Degeneração Hepatolenticular , Fígado , Animais , Degeneração Hepatolenticular/microbiologia , Degeneração Hepatolenticular/terapia , Camundongos , Humanos , Fígado/patologia , Masculino , Feminino , RNA Ribossômico 16S/genética , Adulto , Cobre , Camundongos Endogâmicos C57BL , Antibacterianos/farmacologia , Adulto Jovem
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