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1.
Nature ; 621(7980): 840-848, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37674084

RESUMO

In both cancer and infections, diseased cells are presented to human Vγ9Vδ2 T cells through an 'inside out' signalling process whereby structurally diverse phosphoantigen (pAg) molecules are sensed by the intracellular domain of butyrophilin BTN3A11-4. Here we show how-in both humans and alpaca-multiple pAgs function as 'molecular glues' to promote heteromeric association between the intracellular domains of BTN3A1 and the structurally similar butyrophilin BTN2A1. X-ray crystallography studies visualized that engagement of BTN3A1 with pAgs forms a composite interface for direct binding to BTN2A1, with various pAg molecules each positioned at the centre of the interface and gluing the butyrophilins with distinct affinities. Our structural insights guided mutagenesis experiments that led to disruption of the intracellular BTN3A1-BTN2A1 association, abolishing pAg-mediated Vγ9Vδ2 T cell activation. Analyses using structure-based molecular-dynamics simulations, 19F-NMR investigations, chimeric receptor engineering and direct measurement of intercellular binding force revealed how pAg-mediated BTN2A1 association drives BTN3A1 intracellular fluctuations outwards in a thermodynamically favourable manner, thereby enabling BTN3A1 to push off from the BTN2A1 ectodomain to initiate T cell receptor-mediated γδ T cell activation. Practically, we harnessed the molecular-glue model for immunotherapeutics design, demonstrating chemical principles for developing both small-molecule activators and inhibitors of human γδ T cell function.


Assuntos
Butirofilinas , Ativação Linfocitária , Fosfoproteínas , Receptores de Antígenos de Linfócitos T gama-delta , Linfócitos T , Animais , Humanos , Antígenos CD/imunologia , Antígenos CD/metabolismo , Butirofilinas/imunologia , Butirofilinas/metabolismo , Camelídeos Americanos/imunologia , Simulação de Dinâmica Molecular , Fosfoproteínas/imunologia , Fosfoproteínas/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Cristalografia por Raios X , Ressonância Magnética Nuclear Biomolecular , Termodinâmica
2.
Mol Cell ; 81(16): 3368-3385.e9, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34375583

RESUMO

The mechanistic understanding of nascent RNAs in transcriptional control remains limited. Here, by a high sensitivity method methylation-inscribed nascent transcripts sequencing (MINT-seq), we characterized the landscapes of N6-methyladenosine (m6A) on nascent RNAs. We uncover heavy but selective m6A deposition on nascent RNAs produced by transcription regulatory elements, including promoter upstream antisense RNAs and enhancer RNAs (eRNAs), which positively correlates with their length, inclusion of m6A motif, and RNA abundances. m6A-eRNAs mark highly active enhancers, where they recruit nuclear m6A reader YTHDC1 to phase separate into liquid-like condensates, in a manner dependent on its C terminus intrinsically disordered region and arginine residues. The m6A-eRNA/YTHDC1 condensate co-mixes with and facilitates the formation of BRD4 coactivator condensate. Consequently, YTHDC1 depletion diminished BRD4 condensate and its recruitment to enhancers, resulting in inhibited enhancer and gene activation. We propose that chemical modifications of eRNAs together with reader proteins play broad roles in enhancer activation and gene transcriptional control.


Assuntos
Adenosina/análogos & derivados , Proteínas de Ciclo Celular/genética , Proteínas do Tecido Nervoso/genética , Fatores de Processamento de RNA/genética , RNA/genética , Fatores de Transcrição/genética , Adenosina/genética , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica/genética , Humanos , Metilação , Elementos Reguladores de Transcrição/genética , Ativação Transcricional/genética
3.
Plant Cell ; 36(7): 2729-2745, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38652680

RESUMO

Flowering is a key developmental transition in the plant life cycle. In temperate climates, flowering often occurs in response to the perception of seasonal cues such as changes in day-length and temperature. However, the mechanisms that have evolved to control the timing of flowering in temperate grasses are not fully understood. We identified a Brachypodium distachyon mutant whose flowering is delayed under inductive long-day conditions due to a mutation in the JMJ1 gene, which encodes a Jumonji domain-containing protein. JMJ1 is a histone demethylase that mainly demethylates H3K4me2 and H3K4me3 in vitro and in vivo. Analysis of the genome-wide distribution of H3K4me1, H3K4me2, and H3K4me3 in wild-type plants by chromatin immunoprecipitation and sequencing combined with RNA sequencing revealed that H3K4m1 and H3K4me3 are positively associated with gene transcript levels, whereas H3K4me2 is negatively correlated with transcript levels. Furthermore, JMJ1 directly binds to the chromatin of the flowering regulator genes VRN1 and ID1 and affects their transcription by modifying their H3K4me2 and H3K4me3 levels. Genetic analyses indicated that JMJ1 promotes flowering by activating VRN1 expression. Our study reveals a role for JMJ1-mediated chromatin modification in the proper timing of flowering in B. distachyon.


Assuntos
Brachypodium , Flores , Regulação da Expressão Gênica de Plantas , Histonas , Proteínas de Plantas , Brachypodium/genética , Brachypodium/fisiologia , Flores/genética , Flores/fisiologia , Flores/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Histonas/metabolismo , Mutação/genética , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Cromatina/metabolismo , Cromatina/genética
4.
Nature ; 595(7869): 735-740, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34040254

RESUMO

The functional engagement between an enhancer and its target promoter ensures precise gene transcription1. Understanding the basis of promoter choice by enhancers has important implications for health and disease. Here we report that functional loss of a preferred promoter can release its partner enhancer to loop to and activate an alternative promoter (or alternative promoters) in the neighbourhood. We refer to this target-switching process as 'enhancer release and retargeting'. Genetic deletion, motif perturbation or mutation, and dCas9-mediated CTCF tethering reveal that promoter choice by an enhancer can be determined by the binding of CTCF at promoters, in a cohesin-dependent manner-consistent with a model of 'enhancer scanning' inside the contact domain. Promoter-associated CTCF shows a lower affinity than that at chromatin domain boundaries and often lacks a preferred motif orientation or a partnering CTCF at the cognate enhancer, suggesting properties distinct from boundary CTCF. Analyses of cancer mutations, data from the GTEx project and risk loci from genome-wide association studies, together with a focused CRISPR interference screen, reveal that enhancer release and retargeting represents an overlooked mechanism that underlies the activation of disease-susceptibility genes, as exemplified by a risk locus for Parkinson's disease (NUCKS1-RAB7L1) and three loci associated with cancer (CLPTM1L-TERT, ZCCHC7-PAX5 and PVT1-MYC).


Assuntos
Fator de Ligação a CCCTC/genética , Elementos Facilitadores Genéticos , Predisposição Genética para Doença , Regiões Promotoras Genéticas , Sistemas CRISPR-Cas , Proteínas de Ciclo Celular/genética , Células Cultivadas , Cromatina , Proteínas Cromossômicas não Histona/genética , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Células MCF-7 , Neoplasias/genética , Células-Tronco Neurais , Oncogenes , Doença de Parkinson/genética , Coesinas
5.
Nucleic Acids Res ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967000

RESUMO

Mitochondrial transcripts in Trypanosoma brucei require extensive uridine insertion/deletion RNA editing to generate translatable open reading frames. The RNA editing substrate binding complex (RESC) serves as the scaffold that coordinates the protein-protein and protein-RNA interactions during editing. RESC broadly contains two modules termed the guide RNA binding complex (GRBC) and the RNA editing mediator complex (REMC), as well as organizer proteins. How the protein and RNA components of RESC dynamically interact to facilitate editing is not well understood. Here, we examine the roles of organizer proteins, RESC8 and RESC14, in facilitating RESC dynamics. High-throughput sequencing of editing intermediates reveals an overlapping RESC8 and RESC14 function during editing progression across multiple transcripts. Blue native PAGE analysis demonstrates that RESC14 is essential for incorporation of RESC8 into a large RNA-containing complex, while RESC8 is important in recruiting a smaller ribonucleoprotein complex (RNP) to this large complex. Proximity labeling shows that RESC14 is important for stable RESC protein-protein interactions, as well as RESC-RECC associations. Together, our data support a model in which RESC14 is necessary for assembly of editing competent RESC through recruitment of an RNP containing RESC8, GRBC and gRNA to REMC and mRNA.

6.
Plant J ; 118(5): 1475-1485, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38402593

RESUMO

Plant cell walls are essential for defining plant growth and development, providing structural support to the main body and responding to abiotic and biotic cues. Cellulose, the main structural polymer of plant cell walls, is synthesized at the plasma membrane by cellulose synthase complexes (CSCs). The construction and transport of CSCs to and from the plasma membrane is poorly understood but is known to rely on the coordinated activity of cellulose synthase-interactive protein 1 (CSI1), a key regulator of CSC trafficking. In this study, we found that Trs85, a TRAPPIII complex subunit, interacted with CSI1 in vitro. Using functional genetics and live-cell imaging, we have shown that trs85-1 mutants have reduced cellulose content, stimulated CSC delivery, an increased population of static CSCs and deficient clathrin-mediated endocytosis in the primary cell wall. Overall, our findings suggest that Trs85 has a dual role in the trafficking of CSCs, by negatively regulating the exocytosis and clathrin-mediated endocytosis of CSCs.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Parede Celular , Celulose , Endocitose , Glucosiltransferases , Transporte Proteico , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/enzimologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Glucosiltransferases/metabolismo , Glucosiltransferases/genética , Parede Celular/metabolismo , Endocitose/fisiologia , Celulose/metabolismo , Clatrina/metabolismo , Membrana Celular/metabolismo , Exocitose/fisiologia , Mutação , Proteínas de Transporte
7.
J Med Genet ; 61(6): 553-565, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38341271

RESUMO

BACKGROUND: The association between the TDRD6 variants and human infertility remains unclear, as only one homozygous missense variant of TDRD6 was found to be associated with oligoasthenoteratozoospermia (OAT). METHODS: Whole-exome sequencing and Sanger sequencing were employed to identify potential pathogenic variants of TDRD6 in infertile men. Histology, immunofluorescence, immunoblotting and ultrastructural analyses were conducted to clarify the structural and functional abnormalities of sperm in mutated patients. Tdrd6-knockout mice were generated using the CRISPR-Cas9 system. Total RNA-seq and single-cell RNA-seq (scRNA-seq) analyses were used to elucidate the underlying molecular mechanisms, followed by validation through quantitative RT-PCR and immunostaining. Intracytoplasmic sperm injection (ICSI) was also used to assess the efficacy of clinical treatment. RESULTS: Bi-allelic TDRD6 variants were identified in five unrelated Chinese individuals with OAT, including homozygous loss-of-function variants in two consanguineous families. Notably, besides reduced concentrations and impaired motility, a significant occurrence of acrosomal hypoplasia was detected in multiple spermatozoa among five patients. Using the Tdrd6-deficient mice, we further elucidate the pivotal role of TDRD6 in spermiogenesis and acrosome identified. In addition, the mislocalisation of crucial chromatoid body components DDX4 (MVH) and UPF1 was also observed in round spermatids from patients harbouring TDRD6 variants. ScRNA-seq analysis of germ cells from a patient with TDRD6 variants revealed that TDRD6 regulates mRNA metabolism processes involved in spermatid differentiation and cytoplasmic translation. CONCLUSION: Our findings strongly suggest that TDRD6 plays a conserved role in spermiogenesis and confirms the causal relationship between TDRD6 variants and human OAT. Additionally, this study highlights the unfavourable ICSI outcomes in individuals with bi-allelic TDRD6 variants, providing insights for potential clinical treatment strategies.


Assuntos
Alelos , Astenozoospermia , Sequenciamento do Exoma , Camundongos Knockout , Espermatogênese , Adulto , Animais , Humanos , Masculino , Camundongos , Acrossomo/patologia , Astenozoospermia/genética , Astenozoospermia/patologia , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Oligospermia/genética , Oligospermia/patologia , Linhagem , Injeções de Esperma Intracitoplásmicas , Espermatogênese/genética , Espermatozoides/patologia , Espermatozoides/metabolismo
8.
Br J Haematol ; 204(6): 2378-2389, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38581290

RESUMO

To explore the impact of letermovir (LET) prophylaxis on cytomegalovirus (CMV) reactivation and resistance in both adult and paediatric umbilical cord blood transplantation (UCBT) patients, we retrospectively compared 43 UCBT patients who received LET as CMV prophylaxis with a historical cohort of 207 UCBT patients without LET usage. LET was administered from Day +1 to Day +100. The 180-day cumulative incidence of CMV reactivation (47.3% vs. 74.4%, p < 0.001) and the proportion of refractory CMV reactivation (15.0% vs. 42.9%, p = 0.016) were significantly lower than those in the control group. However, more frequent late CMV infection (31.0% vs. 4.3%, p = 0.002) and the 180-day cumulative incidence of Epstein-Barr virus (EBV) reactivation (9.3% vs. 3.4%, p = 0.087) were observed in UCBT patients with LET prophylaxis. Meanwhile, older age (>15 years old) and the occurrence of pre-engraftment syndrome were identified as the significant risk factors for CMV reactivation, and in patients at high risk, the incidence of CMV reactivation in the LET group was lower than that in the control group (46.7% vs. 86.5%, p < 0.001), while this decline was less pronounced among patients at low risk (47.8% vs. 62.1%, p = 0.120).


Assuntos
Antivirais , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Infecções por Citomegalovirus , Citomegalovirus , Quinazolinas , Ativação Viral , Humanos , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Masculino , Infecções por Citomegalovirus/prevenção & controle , Infecções por Citomegalovirus/etiologia , Feminino , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/fisiologia , Adulto , Estudos Retrospectivos , Adolescente , Pessoa de Meia-Idade , Criança , Ativação Viral/efeitos dos fármacos , Antivirais/uso terapêutico , Quinazolinas/uso terapêutico , Quinazolinas/farmacologia , Pré-Escolar , Farmacorresistência Viral , Adulto Jovem , Lactente , Idoso , Acetatos
9.
Br J Haematol ; 204(6): 2390-2399, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38664918

RESUMO

In this multicentre, real-world study, we aimed to identify the clinical outcomes and safety of allogeneic haematopoietic stem cell transplantation (allo-HSCT) in T-lymphoblastic lymphoma (T-LBL). A total of 130 Ann Arbor stage III or IV T-LBL patients (>16 years) treated with allo-HSCT across five transplant centres were enrolled. The 2-year cumulative incidence of disease progression, the probabilities of progression-free survival (PFS), overall survival (OS) and non-relapse mortality (NRM) after allo-HSCT were 21.0%, 69.8%, 79.5% and 9.2% respectively. Patients with central nervous system (CNS) involvement had a higher cumulative incidence of disease progression compared with those without CNS involvement (57.1% vs. 18.9%, HR 3.78, p = 0.014). Patients receiving allo-HSCT in non-remission (NR) had a poorer PFS compared with those receiving allo-HSCT in complete remission (CR) or partial remission (49.2% vs. 72.7%, HR 2.21, p = 0.041). Particularly for patients with bone marrow involvement and achieving CR before allo-HSCT, measurable residual disease (MRD) positivity before allo-HSCT was associated with a poorer PFS compared with MRD negativity (62.7% vs. 86.8%, HR 1.94, p = 0.036). On multivariate analysis, CNS involvement at diagnosis and receiving allo-HSCT in NR were associated with disease progression. Thus, our real-world data suggested that allo-HSCT appeared to be an effective therapy for adult T-LBL patients with Ann Arbor stage III or IV disease.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Humanos , Adulto , Masculino , Feminino , Pessoa de Meia-Idade , China/epidemiologia , Adolescente , Adulto Jovem , Transplante Homólogo , Condicionamento Pré-Transplante/métodos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Intervalo Livre de Doença
10.
Small ; 20(26): e2308861, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38372029

RESUMO

The anabolism of tumor cells can not only support their proliferation, but also endow them with a steady influx of exogenous nutrients. Therefore, consuming metabolic substrates or limiting access to energy supply can be an effective strategy to impede tumor growth. Herein, a novel treatment paradigm of starving-like therapy-triple energy-depleting therapy-is illustrated by glucose oxidase (GOx)/dc-IR825/sorafenib liposomes (termed GISLs), and such a triple energy-depleting therapy exhibits a more effective tumor-killing effect than conventional starvation therapy that only cuts off one of the energy supplies. Specifically, GOx can continuously consume glucose and generate toxic H2O2 in the tumor microenvironment (including tumor cells). After endocytosis, dc-IR825 (a near-infrared cyanine dye) can precisely target mitochondria and exert photodynamic and photothermal activities upon laser irradiation to destroy mitochondria. The anti-angiogenesis effect of sorafenib can further block energy and nutrition supply from blood. This work exemplifies a facile and safe method to exhaust the energy in a tumor from three aspects and starve the tumor to death and also highlights the importance of energy depletion in tumor treatment. It is hoped that this work will inspire the development of more advanced platforms that can combine multiple energy depletion therapies to realize more effective tumor treatment.


Assuntos
Glucose Oxidase , Lipossomos , Sorafenibe , Lipossomos/química , Humanos , Glucose Oxidase/metabolismo , Glucose Oxidase/química , Animais , Sorafenibe/farmacologia , Linhagem Celular Tumoral , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Metabolismo Energético , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/química , Indóis
11.
J Autoimmun ; 147: 103274, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38936148

RESUMO

Chronic graft-versus-host disease (cGVHD) is the most common long-term complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The patients with pulmonary cGVHD in particular have a very poor prognosis. NK cells are the first reconstituted lymphocyte subset after allo-HSCT; however, the impact of reconstituted NK cells on cGVHD is unclear. Here, we found allogeneic recipients showed obvious pulmonary cGVHD. Surprisingly, deletion of reconstituted NK cells resulted in maximal relief of pulmonary cGVHD. Mechanistically, reconstituted NK cells with donor profiles modulated the pulmonary inflammatory microenvironment to trigger cGVHD. Reconstituted NK cells secreted IFN-γ and TNF-α to induce CXCL10 production by epithelial cells, which recruited macrophages and CD4+ T cells to the lungs. Then macrophages and CD4+ T cells were activated by the inflammatory microenvironment, thereby mediating lung injury. Through assessment of differences in cellular energy, we found that CD74+ NK cells with high mitochondrial potential and pro-inflammatory activity triggered pulmonary cGVHD. Furthermore, targeted elimination of CD74+ NK cells using the anti-CD74 antibody significantly alleviated pulmonary cGVHD but preserved the CD74- NK cells to exert graft-versus-leukemia (GVL) effects. Data from human samples corroborated our findings in mouse models. Collectively, our results reveal that reconstituted CD74+ NK cells trigger pulmonary cGVHD and suggest that administration of CD74 antibody was a potential therapeutic for patients with cGVHD.


Assuntos
Transplante de Medula Óssea , Doença Enxerto-Hospedeiro , Células Matadoras Naturais , Transplante Homólogo , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Animais , Camundongos , Humanos , Transplante de Medula Óssea/efeitos adversos , Doença Crônica , Masculino , Feminino , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Modelos Animais de Doenças , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Camundongos Endogâmicos C57BL , Reconstituição Imune , Síndrome de Bronquiolite Obliterante
12.
Clin Genet ; 105(1): 99-105, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37715646

RESUMO

Non-obstructive azoospermia (NOA) is the most severe form of human male infertility, and the genetic causes of NOA with meiotic arrest remain largely unclear. In this study, we identified novel compound heterozygous MEIOB variants (c.814C > T: p.R272X and c.976G > A: p.A326T) and a previously undescribed homozygous non-canonical splicing variant of MEIOB (c.528 + 3A > C) in two NOA-affected individuals from two irrelevant Chinese families. MEIOB missense variant (p.A326T) significantly reduced protein abundance and nonsense variant (p.R272X) produced a truncated protein. Both of two variants impaired the MEIOB-SPATA22 interaction. The MEIOB non-canonical splicing variant resulted in whole Exon 6 skipping by minigene assay, which was predicted to produce a frameshift truncated protein (p.S111Rfs*32). Histological and immunostaining analysis indicated that both patients exhibited a similar phenotype as we previously reported in Meiob mutant mice, that is, absence of spermatids in seminiferous tubules and meiotic arrest. Our study identified three novel pathogenic variants of MEIOB in NOA patients, extending the mutation spectrum of the MEIOB and highlighting the contribution of meiotic recombination related genes in human fertility.


Assuntos
Azoospermia , Infertilidade Masculina , Humanos , Masculino , Camundongos , Animais , Azoospermia/genética , Azoospermia/patologia , Infertilidade Masculina/genética , Mutação/genética , Proteínas/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Meiose/genética , Proteínas de Ligação a DNA/genética
13.
Blood ; 140(26): 2788-2804, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-35981475

RESUMO

Relapse is a leading cause of death after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for acute myeloid leukemia (AML). However, the underlying mechanisms remain poorly understood. Natural killer (NK) cells play a crucial role in tumor surveillance and cancer immunotherapy, and NK cell dysfunction has been observed in various tumors. Here, we performed ex vivo experiments to systematically characterize the mechanisms underlying the dysfunction of bone marrow-derived NK (BMNK) cells isolated from AML patients experiencing early relapse after allo-HSCT. We demonstrated that higher levels of active transforming growth factor ß1 (TGF-ß1) were associated with impaired effector function of BMNK cells in these AML patients. TGF-ß1 activation was induced by the overexpression of glycoprotein A repetitions predominant on the surface of CD4+ T cells. Active TGF-ß1 significantly suppressed mTORC1 activity, mitochondrial oxidative phosphorylation, the proliferation, and cytotoxicity of BMNK cells. Furthermore, pretreatment with the clinical stage TGF-ß1 pathway inhibitor, galunisertib, significantly restored mTORC1 activity, mitochondrial homeostasis, and cytotoxicity. Importantly, the blockade of the TGF-ß1 signaling improved the antitumor activity of NK cells in a leukemia xenograft mouse model. Thus, our findings reveal a mechanism explaining BMNK cell dysfunction and suggest that targeted inhibition of TGF-ß1 signaling may represent a potential therapeutic intervention to improve outcomes in AML patients undergoing allo-HSCT or NK cell-based immunotherapy.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Humanos , Animais , Camundongos , Medula Óssea/patologia , Fator de Crescimento Transformador beta1 , Transplante Homólogo , Leucemia Mieloide Aguda/patologia , Células Matadoras Naturais/patologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Crônica , Recidiva
14.
MMWR Morb Mortal Wkly Rep ; 73(12): 255-259, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38547027

RESUMO

Gonorrhea is a widespread sexually transmitted infection; in 2022, China reported 96,313 cases of gonorrhea, making it the fourth most common notifiable infectious disease in the country after viral hepatitis, pulmonary tuberculosis, and syphilis. The rise in prevalence in antimicrobial-resistant strains, particularly the international spread of ceftriaxone-resistant clones, poses a formidable challenge to gonorrhea control. The China Gonococcal Resistance Surveillance Program (China-GRSP), established in 1987 and covering 19 of 34 provincial-level administrative units, continuously monitors gonococcal antimicrobial resistance. In 2022, 13 China-GRSP sentinel sites collected 2,804 gonococcal isolates, representing 2.9% of all cases reported in China, and 4.1% of cases reported in the 13 participating provinces. The prevalence of Neisseria gonorrhoeae resistance to ceftriaxone was 8.1%, approximately three times the 2017 rate of 2.9%; five provinces reported >10% ceftriaxone resistance. Resistance prevalences to cefixime, azithromycin, tetracycline, penicillin, and ciprofloxacin were 16.0%, 16.9%, 77.1%, 77.8%, and 97.6%, respectively. Only one case of spectinomycin resistance was reported. These data highlight a substantial increase in ceftriaxone resistance from 2017 to 2022. Effective diagnosis and treatment and appropriate management of sex partners are essential to protect the health of infected persons and prevent ongoing transmission of gonorrhea, including transmission of resistant strains. Identifying reasons for the spread of ceftriaxone-resistant N. gonorrhoeae in China could guide strategies, such as antibiotic stewardship, to mitigate the rising resistance rate and curb the spread of resistant strains.


Assuntos
Anti-Infecciosos , Gonorreia , Humanos , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Ceftriaxona/farmacologia , Ceftriaxona/uso terapêutico , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ciprofloxacina , Neisseria gonorrhoeae , Azitromicina , Anti-Infecciosos/farmacologia , China/epidemiologia , Farmacorresistência Bacteriana
15.
Bioorg Med Chem Lett ; 107: 129769, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670537

RESUMO

Among small-molecule CDK4/6 inhibitors (palbociclib, ribociclib, and abemaciclib) approved for metastatic breast cancers, abemaciclib has a more tolerable adverse effects in clinic. This is attributable to preferential inhibition of CDK4 over CDK6. In our search for a biased CDK4 inhibitor, we discovered a series of pyrimidine-indazole inhibitors. SAR studies led us to TQB3616 as a preferential CDK4 inhibitor. TQB3616 exhibited improvements in both enzymatic and cellular proliferation inhibitory potency when tested side-by-side with the FDA approved palbociclib and abemaciclib. TQB3616 also possessed favorable PK profile in multiple species. These differentiated properties, together with excellent GLP safety profile warranted TQB3616 moving to clinic. TQB3616 entered into clinical development in 2019 and currently in phase III clinical trials (NCT05375461, NCT05365178).


Assuntos
Proliferação de Células , Quinase 4 Dependente de Ciclina , Inibidores de Proteínas Quinases , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/metabolismo , Humanos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/síntese química , Relação Estrutura-Atividade , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Animais , Descoberta de Drogas , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Dose-Resposta a Droga , Pirimidinas/química , Pirimidinas/farmacologia , Pirimidinas/síntese química , Ratos , Ensaios de Seleção de Medicamentos Antitumorais , Avaliação Pré-Clínica de Medicamentos
16.
Gynecol Endocrinol ; 40(1): 2351525, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38726683

RESUMO

OBJECTIVE: Stable luteal cell function is an important prerequisite for reproductive ability and embryonic development. However, luteal insufficiency seriously harms couples who have the desire to have a pregnancy, and the most important thing is that there is no complete solution. In addition, Vaspin has been shown to have regulatory effects on luteal cells, but the complex mechanisms involved have not been fully elucidated. Therefore, this study aimed to explore the effect of Vaspin on rat luteal cells and its mechanism. METHODS: Granulosa lutein cells separated from the ovary of female rats were incubated for 24h with gradient concentrations of Vaspin, and granulosa lutein cells incubated with 0.5% bovine serum albumin were used as controls. The proliferation, apoptosis, angiogenesis, progesterone (P4) and estradiol (E2) were detected by CCK-8, Anneixn-FITC/PI staining, angiogenesis experiment and ELISA. Western blot was applied to observe the expression levels of proteins related to cell proliferation, apoptosis, angiogenesis and MEK/MAPK signaling pathway. RESULTS: Compared with the Control group, Vaspin could significantly up-regulate the proliferation of granulosa lutein cells and reduce the apoptosis. Moreover, Vaspin promoted the angiogenesis of granulosa lutein cells and the production of P4 and E2 in a concentration-dependent manner. Furthermore, Vaspin up-regulated the CyclinD1, CyclinB1, Bcl2, VEGFA and FGF-2 expression in granulosa lutein cells, and down-regulated the level of Bax. Also, Vaspin increased the p-MEK1 and p-p38 levels. CONCLUSION: Vaspin can up-regulate the proliferation and steroidogenesis of rat luteal cells and reduce apoptosis, which may be related to the influence of MEK/MAPK activity.


Assuntos
Apoptose , Proliferação de Células , Células Lúteas , Progesterona , Serpinas , Animais , Feminino , Proliferação de Células/efeitos dos fármacos , Serpinas/metabolismo , Serpinas/farmacologia , Ratos , Células Lúteas/efeitos dos fármacos , Células Lúteas/metabolismo , Apoptose/efeitos dos fármacos , Progesterona/farmacologia , Estradiol/farmacologia , Células Cultivadas , Ratos Sprague-Dawley , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos
17.
Exp Aging Res ; 50(2): 225-247, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38192191

RESUMO

Empathy, the ability to understand and respond to the experiences of others, is an important skill for maintaining good relationships throughout one's life. Previous research indicated that emotional empathy remained stable or even increased in older adults compared to younger adults, while cognitive empathy showed age-related deficits. Based on the selective engagement hypothesis, this deficit was not caused by a decline in cognitive functioning, but by a lack of willingness to judge the target person's emotions more precisely, that is, by a lack of interaction motivation. In order to provide more evidence on the causes of empathic aging in older adults, the current study investigated the influence of interaction motivation on empathy in older adults in an Eastern cultural context (China) based on the selective engagement hypothesis. This study used older adults and younger adults as subjects. Through two experiments, empathy was measured by the multiple empathy test (Experiment 1) and film tasks (Experiment 2); at the same time, use accountability instructions (Experiment 1), the age-related events (Experiment 2) to manipulate interaction motivation. The results showed that emotional empathy was significantly higher in older adults than in younger adults, regardless of whether interaction motivation was elicited. In terms of cognitive empathy, when there is no motivation, the cognitive empathy of older adults is significantly lower than that of younger adults. When the interaction motivation is stimulated, the cognitive empathy of older adults is no less than that of younger adults. This suggested that empathic aging in older adults was not a permanent decline in cognitive empathy, but rather a decline in interaction motivation, supporting the selective engagement hypothesis.


Assuntos
Empatia , Motivação , Humanos , Idoso , Envelhecimento , Emoções , Cognição
18.
Water Sci Technol ; 89(9): 2523-2537, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38747965

RESUMO

Miscanthus sacchariflorus is previously demonstrated to be a potential candidate for remediation of cadmium (Cd) pollution. To explore its resistance strategy to Cd, a hydroponic experiment was conducted to determine the variations of photosynthetic activity in leaves and physiological response in roots of this plant. Results showed that the root of M. sacchariflorus was the primary location for Cd accumulation. The bioconcentration factor in the roots and rhizomes was >1, and the translocation factor from underground to aboveground was <1. Throughout the experimental period, treatment with 0.06 mM Cd2+ did not significantly alter the contents of chlorophyll a, chlorophyll b, or carotenoid. By contrast, treatment with 0.15 and 0.30 mM Cd2+ decreased the contents of chlorophyll a, chlorophyll b, and carotenoid; caused the deformation of the chlorophyll fluorescence transient curve; reduced the photochemical efficiency of photosystem II; and increased the contents of non-protein thiols, total flavone, and total phenol. These results indicate that M. sacchariflorus has good adaptability to 0.06 mM Cd2+. Moreover, the accumulation of the non-protein thiols, total flavone, and total phenol in roots may promote the chelation of Cd2+, thus alleviating Cd toxicity. This study provides theoretical support for using M. sacchariflorus to remediate Cd-polluted wetlands.


Assuntos
Cádmio , Fotossíntese , Poaceae , Compostos de Sulfidrila , Cádmio/toxicidade , Cádmio/metabolismo , Fotossíntese/efeitos dos fármacos , Poaceae/metabolismo , Poaceae/efeitos dos fármacos , Compostos de Sulfidrila/metabolismo , Clorofila/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Biodegradação Ambiental
19.
Lancet Oncol ; 24(6): 646-657, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37182538

RESUMO

BACKGROUND: Adding CDK4/6 inhibitor dalpiciclib to fulvestrant significantly prolonged progression-free survival in patients with hormone receptor-positive, HER2-negative advanced breast cancer progressing after endocrine therapy. We aimed to assess the efficacy and safety of dalpiciclib plus letrozole or anastrozole in patients with hormone receptor-positive, HER2-negative advanced breast cancer who had no previous systemic therapy in the advanced setting. METHODS: DAWNA-2 is a randomised, double-blind, placebo-controlled, phase 3 trial done at 42 hospitals in China. Eligible patients were aged 18-75 years, of any menopausal status, had an ECOG performance status of 0-1, and had pathologically confirmed hormone receptor-positive, HER2-negative untreated advanced breast cancer. Patients were randomly assigned (2:1) to receive oral dalpiciclib (150 mg per day for 3 weeks, followed by 1 week off) or matching placebo. Both groups also received endocrine therapy: either 2·5 mg letrozole or 1 mg anastrozole orally once daily continuously. Randomisation was using an interactive web response system (block size of six) and stratified according to visceral metastasis, previous endocrine therapy in the adjuvant or neoadjuvant setting, and endocrine therapy partner. All investigators, patients, and the funders of the study were masked to group allocation. We present the results of the preplanned interim analyses for the primary endpoint of investigator-assessed progression-free survival, which was assessed in all randomly assigned patients who met the eligibility criteria by intention-to treat. Safety was analysed in all randomly assigned patients who received at least one dose of study treatment. The superiority boundary was calculated as a one-sided p value of 0·0076 or less. This trial is registered with ClinicalTrials.gov, NCT03966898, and is ongoing but closed to recruitment. FINDINGS: Between July 19, 2019, and Dec 25, 2020, 580 patients were screened and 456 were eligible and randomly assigned to the dalpiciclib group (n=303) or placebo group (n=153). At data cutoff (June 1, 2022), median follow-up was 21·6 months (IQR 18·3-25·9), and 103 (34%) of 303 patients in the dalpiciclib group and 83 (54%) of 153 patients in the placebo group had disease progression or died. Median progression-free survival was significantly longer in the dalpiciclib group than in the placebo group (30·6 months [95% CI 30·6-not reached] vs 18·2 months [16·5-22·5]; stratified hazard ratio 0·51 [95% CI 0·38-0·69]; one-sided log-rank p<0·0001). Adverse events of grade 3 or 4 were reported in 271 (90%) of 302 patients in the dalpiciclib group and 18 (12%) of 153 patients in the placebo group. The most common adverse events of grade 3 or 4 were neutropenia (259 [86%] in the dalpiciclib group vs none in the placebo group) and leukopenia (201 [67%] vs none). Serious adverse events were reported for 36 (12%) patients in the dalpiciclib group and ten (7%) patients in the placebo group. Two treatment-related deaths occurred, both in the dalpiciclib group (deaths from unknown causes). INTERPRETATION: Our findings suggest that dalpiciclib plus letrozole or anastrozole could be a novel standard first-line treatment for patients with hormone receptor-positive, HER2-negative advanced breast cancer, and is an alternative option to the current treatment landscape. FUNDING: Jiangsu Hengrui Pharmaceuticals and Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Letrozol , Anastrozol , Resultado do Tratamento , Intervalo Livre de Doença , Receptor ErbB-2 , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Método Duplo-Cego
20.
J Am Chem Soc ; 145(44): 23910-23917, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37883710

RESUMO

The merger of electrochemistry and transition metal catalysis has emerged as a powerful tool to join two electrophiles in an enantioselective manner. However, the development of enantioselective electroreductive cross-couplings of olefins remains a challenge. Inspired by the advantages of the synergistic use of electrochemistry with nickel catalysis, we present here a Ni-catalyzed enantioselective electroreductive cross-coupling of acrylates with aryl halides and alkyl bromides, which affords chiral α-aryl carbonyls in good to excellent enantioselectivity. Additionally, this catalytic reaction can be applied to (hetero)aryl chlorides, which is difficult to achieve by other methods. The combination of cyclic voltammetry analysis with electrode potential studies suggests that the NiI species activates aryl halides by oxidative addition and alkyl bromides by single-electron transfer.

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