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1.
Nat Immunol ; 25(4): 622-632, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38454157

RESUMEN

The development of a vaccine specific to severe acute respiratory syndrome coronavirus 2 Omicron has been hampered due to its low immunogenicity. Here, using reverse mutagenesis, we found that a phenylalanine-to-serine mutation at position 375 (F375S) in the spike protein of Omicron to revert it to the sequence found in Delta and other ancestral strains significantly enhanced the immunogenicity of Omicron vaccines. Sequence FAPFFAF at position 371-377 in Omicron spike had a potent inhibitory effect on macrophage uptake of receptor-binding domain (RBD) nanoparticles or spike-pseudovirus particles containing this sequence. Omicron RBD enhanced binding to Siglec-9 on macrophages to impair phagocytosis and antigen presentation and promote immune evasion, which could be abrogated by the F375S mutation. A bivalent F375S Omicron RBD and Delta-RBD nanoparticle vaccine elicited potent and broad nAbs in mice, rabbits and rhesus macaques. Our research suggested that manipulation of the Siglec-9 pathway could be a promising approach to enhance vaccine response.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Ratones , Conejos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Macaca mulatta , Macrófagos , Nanovacunas , Fagocitosis , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico
2.
Nature ; 627(8002): 80-87, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38418888

RESUMEN

Integrated microwave photonics (MWP) is an intriguing technology for the generation, transmission and manipulation of microwave signals in chip-scale optical systems1,2. In particular, ultrafast processing of analogue signals in the optical domain with high fidelity and low latency could enable a variety of applications such as MWP filters3-5, microwave signal processing6-9 and image recognition10,11. An ideal integrated MWP processing platform should have both an efficient and high-speed electro-optic modulation block to faithfully perform microwave-optic conversion at low power and also a low-loss functional photonic network to implement various signal-processing tasks. Moreover, large-scale, low-cost manufacturability is required to monolithically integrate the two building blocks on the same chip. Here we demonstrate such an integrated MWP processing engine based on a 4 inch wafer-scale thin-film lithium niobate platform. It can perform multipurpose tasks with processing bandwidths of up to 67 GHz at complementary metal-oxide-semiconductor (CMOS)-compatible voltages. We achieve ultrafast analogue computation, namely temporal integration and differentiation, at sampling rates of up to 256 giga samples per second, and deploy these functions to showcase three proof-of-concept applications: solving ordinary differential equations, generating ultra-wideband signals and detecting edges in images. We further leverage the image edge detector to realize a photonic-assisted image segmentation model that can effectively outline the boundaries of melanoma lesion in medical diagnostic images. Our ultrafast lithium niobate MWP engine could provide compact, low-latency and cost-effective solutions for future wireless communications, high-resolution radar and photonic artificial intelligence.


Asunto(s)
Microondas , Niobio , Óptica y Fotónica , Óxidos , Fotones , Inteligencia Artificial , Diagnóstico por Imagen/instrumentación , Diagnóstico por Imagen/métodos , Melanoma/diagnóstico por imagen , Melanoma/patología , Óptica y Fotónica/instrumentación , Óptica y Fotónica/métodos , Radar , Tecnología Inalámbrica , Humanos
3.
Nature ; 630(8015): 189-197, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38811728

RESUMEN

In developing B cells, V(D)J recombination assembles exons encoding IgH and Igκ variable regions from hundreds of gene segments clustered across Igh and Igk loci. V, D and J gene segments are flanked by conserved recombination signal sequences (RSSs) that target RAG endonuclease1. RAG orchestrates Igh V(D)J recombination upon capturing a JH-RSS within the JH-RSS-based recombination centre1-3 (RC). JH-RSS orientation programmes RAG to scan upstream D- and VH-containing chromatin that is presented in a linear manner by cohesin-mediated loop extrusion4-7. During Igh scanning, RAG robustly utilizes only D-RSSs or VH-RSSs in convergent (deletional) orientation with JH-RSSs4-7. However, for Vκ-to-Jκ joining, RAG utilizes Vκ-RSSs from deletional- and inversional-oriented clusters8, inconsistent with linear scanning2. Here we characterize the Vκ-to-Jκ joining mechanism. Igk undergoes robust primary and secondary rearrangements9,10, which confounds scanning assays. We therefore engineered cells to undergo only primary Vκ-to-Jκ rearrangements and found that RAG scanning from the primary Jκ-RC terminates just 8 kb upstream within the CTCF-site-based Sis element11. Whereas Sis and the Jκ-RC barely interacted with the Vκ locus, the CTCF-site-based Cer element12 4 kb upstream of Sis interacted with various loop extrusion impediments across the locus. Similar to VH locus inversion7, DJH inversion abrogated VH-to-DJH joining; yet Vκ locus or Jκ inversion allowed robust Vκ-to-Jκ joining. Together, these experiments implicated loop extrusion in bringing Vκ segments near Cer for short-range diffusion-mediated capture by RC-based RAG. To identify key mechanistic elements for diffusional V(D)J recombination in Igk versus Igh, we assayed Vκ-to-JH and D-to-Jκ rearrangements in hybrid Igh-Igk loci generated by targeted chromosomal translocations, and pinpointed remarkably strong Vκ and Jκ RSSs. Indeed, RSS replacements in hybrid or normal Igk and Igh loci confirmed the ability of Igk-RSSs to promote robust diffusional joining compared with Igh-RSSs. We propose that Igk evolved strong RSSs to mediate diffusional Vκ-to-Jκ joining, whereas Igh evolved weaker RSSs requisite for modulating VH joining by RAG-scanning impediments.


Asunto(s)
Cadenas Pesadas de Inmunoglobulina , Región de Unión de la Inmunoglobulina , Región Variable de Inmunoglobulina , Cadenas kappa de Inmunoglobulina , Recombinación V(D)J , Animales , Femenino , Masculino , Ratones , Alelos , Linfocitos B/inmunología , Linfocitos B/metabolismo , Cromatina/genética , Cromatina/metabolismo , Cromatina/química , Cohesinas/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Cadenas Pesadas de Inmunoglobulina/genética , Región de Unión de la Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Recombinación V(D)J/genética
4.
Immunity ; 53(6): 1315-1330.e9, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33275896

RESUMEN

Various vaccine strategies have been proposed in response to the global COVID-19 pandemic, each with unique strategies for eliciting immune responses. Here, we developed nanoparticle vaccines by covalently conjugating the self-assembled 24-mer ferritin to the receptor binding domain (RBD) and/or heptad repeat (HR) subunits of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) spike (S) protein. Compared to monomer vaccines, nanoparticle vaccines elicited more robust neutralizing antibodies and cellular immune responses. RBD and RBD-HR nanoparticle vaccinated hACE2 transgenic mice vaccinated with RBD and/or RBD-HR nanoparticles exhibited reduced viral load in the lungs after SARS-CoV-2 challenge. RBD-HR nanoparticle vaccines also promoted neutralizing antibodies and cellular immune responses against other coronaviruses. The nanoparticle vaccination of rhesus macaques induced neutralizing antibodies, and T and B cell responses prior to boost immunization; these responses persisted for more than three months. RBD- and HR-based nanoparticles thus present a promising vaccination approach against SARS-CoV-2 and other coronaviruses.


Asunto(s)
Proteínas Bacterianas/inmunología , Vacunas contra la COVID-19/inmunología , COVID-19/inmunología , Ferritinas/inmunología , Helicobacter pylori/metabolismo , Proteínas Recombinantes de Fusión/inmunología , SARS-CoV-2/fisiología , Glicoproteína de la Espiga del Coronavirus/inmunología , Enzima Convertidora de Angiotensina 2/genética , Enzima Convertidora de Angiotensina 2/metabolismo , Animales , Anticuerpos Neutralizantes/metabolismo , Anticuerpos Antivirales/metabolismo , Proteínas Bacterianas/química , Vacunas contra la COVID-19/química , Ferritinas/química , Humanos , Macaca mulatta , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Pandemias , Unión Proteica , Glicoproteína de la Espiga del Coronavirus/química , Vacunación
5.
Nature ; 621(7979): 521-529, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37730866

RESUMEN

Wildfires are thought to be increasing in severity and frequency as a result of climate change1-5. Air pollution from landscape fires can negatively affect human health4-6, but human exposure to landscape fire-sourced (LFS) air pollution has not been well characterized at the global scale7-23. Here, we estimate global daily LFS outdoor fine particulate matter (PM2.5) and surface ozone concentrations at 0.25° × 0.25° resolution during the period 2000-2019 with the help of machine learning and chemical transport models. We found that overall population-weighted average LFS PM2.5 and ozone concentrations were 2.5 µg m-3 (6.1% of all-source PM2.5) and 3.2 µg m-3 (3.6% of all-source ozone), respectively, in 2010-2019, with a slight increase for PM2.5, but not for ozone, compared with 2000-2009. Central Africa, Southeast Asia, South America and Siberia experienced the highest LFS PM2.5 and ozone concentrations. The concentrations of LFS PM2.5 and ozone were about four times higher in low-income countries than in high-income countries. During the period 2010-2019, 2.18 billion people were exposed to at least 1 day of substantial LFS air pollution per year, with each person in the world having, on average, 9.9 days of exposure per year. These two metrics increased by 6.8% and 2.1%, respectively, compared with 2000-2009. Overall, we find that the global population is increasingly exposed to LFS air pollution, with socioeconomic disparities.


Asunto(s)
Contaminación del Aire , Incendios , Ozono , Material Particulado , Humanos , Contaminación del Aire/análisis , Contaminación del Aire/estadística & datos numéricos , Incendios/estadística & datos numéricos , Ozono/análisis , Ozono/provisión & distribución , Material Particulado/análisis , Material Particulado/provisión & distribución , Incendios Forestales/estadística & datos numéricos , Disparidades Socioeconómicas en Salud
6.
Nature ; 590(7845): 338-343, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33442057

RESUMEN

RAG endonuclease initiates Igh V(D)J recombination in progenitor B cells by binding a JH-recombination signal sequence (RSS) within a recombination centre (RC) and then linearly scanning upstream chromatin, presented by loop extrusion mediated by cohesin, for convergent D-RSSs1,2. The utilization of convergently oriented RSSs and cryptic RSSs is intrinsic to long-range RAG scanning3. Scanning of RAG from the DJH-RC-RSS to upstream convergent VH-RSSs is impeded by D-proximal CTCF-binding elements (CBEs)2-5. Primary progenitor B cells undergo a mechanistically undefined contraction of the VH locus that is proposed to provide distal VHs access to the DJH-RC6-9. Here we report that an inversion of the entire 2.4-Mb VH locus in mouse primary progenitor B cells abrogates rearrangement of both VH-RSSs and normally convergent cryptic RSSs, even though locus contraction still occurs. In addition, this inversion activated both the utilization of cryptic VH-RSSs that are normally in opposite orientation and RAG scanning beyond the VH locus through several convergent CBE domains to the telomere. Together, these findings imply that broad deregulation of CBE impediments in primary progenitor B cells promotes RAG scanning of the VH locus mediated by loop extrusion. We further found that the expression of wings apart-like protein homologue (WAPL)10, a cohesin-unloading factor, was low in primary progenitor B cells compared with v-Abl-transformed progenitor B cell lines that lacked contraction and RAG scanning of the VH locus. Correspondingly, depletion of WAPL in v-Abl-transformed lines activated both processes, further implicating loop extrusion in the locus contraction mechanism.


Asunto(s)
Linfocitos B/metabolismo , Proteínas de Unión al ADN/metabolismo , Endonucleasas/metabolismo , Proteínas de Homeodominio/metabolismo , Cadenas Pesadas de Inmunoglobulina/genética , Conformación de Ácido Nucleico , Animales , Linfocitos B/citología , Linfocitos B/enzimología , Línea Celular , Células Cultivadas , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Regulación hacia Abajo , Endonucleasas/deficiencia , Endonucleasas/genética , Puntos de Control de la Fase G1 del Ciclo Celular , Secuenciación de Nucleótidos de Alto Rendimiento , Proteínas de Homeodominio/genética , Ratones , Ratones Endogámicos C57BL , Proteínas/genética , Proteínas/metabolismo , Recombinación V(D)J/genética
7.
Proc Natl Acad Sci U S A ; 121(12): e2311077121, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38470923

RESUMEN

The memory benefit that arises from distributing learning over time rather than in consecutive sessions is one of the most robust effects in cognitive psychology. While prior work has mainly focused on repeated exposures to the same information, in the real world, mnemonic content is dynamic, with some pieces of information staying stable while others vary. Thus, open questions remain about the efficacy of the spacing effect in the face of variability in the mnemonic content. Here, in two experiments, we investigated the contributions of mnemonic variability and the timescale of spacing intervals, ranging from seconds to days, to long-term memory. For item memory, both mnemonic variability and spacing intervals were beneficial for memory; however, mnemonic variability was greater at shorter spacing intervals. In contrast, for associative memory, repetition rather than mnemonic variability was beneficial for memory, and spacing benefits only emerged in the absence of mnemonic variability. These results highlight a critical role for mnemonic variability and the timescale of spacing intervals in the spacing effect, bringing this classic memory paradigm into more ecologically valid contexts.


Asunto(s)
Memoria , Recuerdo Mental , Aprendizaje , Memoria a Largo Plazo , Tiempo
8.
Brief Bioinform ; 25(5)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39276327

RESUMEN

Recent advancements in high-throughput sequencing technologies have significantly enhanced our ability to unravel the intricacies of gene regulatory processes. A critical challenge in this endeavor is the identification of variant effects, a key factor in comprehending the mechanisms underlying gene regulation. Non-coding variants, constituting over 90% of all variants, have garnered increasing attention in recent years. The exploration of gene variant impacts and regulatory mechanisms has spurred the development of various deep learning approaches, providing new insights into the global regulatory landscape through the analysis of extensive genetic data. Here, we provide a comprehensive overview of the development of the non-coding variants models based on bulk and single-cell sequencing data and their model-based interpretation and downstream tasks. This review delineates the popular sequencing technologies for epigenetic profiling and deep learning approaches for discerning the effects of non-coding variants. Additionally, we summarize the limitations of current approaches in variant effect prediction research and outline opportunities for improvement. We anticipate that our study will offer a practical and useful guide for the bioinformatic community to further advance the unraveling of genetic variant effects.


Asunto(s)
Aprendizaje Profundo , Variación Genética , Humanos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Biología Computacional/métodos , Epigénesis Genética
9.
Proc Natl Acad Sci U S A ; 120(26): e2306564120, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37339228

RESUMEN

Immunoglobulin heavy chain variable region exons are assembled in progenitor-B cells, from VH, D, and JH gene segments located in separate clusters across the Igh locus. RAG endonuclease initiates V(D)J recombination from a JH-based recombination center (RC). Cohesin-mediated extrusion of upstream chromatin past RC-bound RAG presents Ds for joining to JHs to form a DJH-RC. Igh has a provocative number and organization of CTCF-binding elements (CBEs) that can impede loop extrusion. Thus, Igh has two divergently oriented CBEs (CBE1 and CBE2) in the IGCR1 element between the VH and D/JH domains, over 100 CBEs across the VH domain convergent to CBE1, and 10 clustered 3'Igh-CBEs convergent to CBE2 and VH CBEs. IGCR1 CBEs segregate D/JH and VH domains by impeding loop extrusion-mediated RAG-scanning. Downregulation of WAPL, a cohesin unloader, in progenitor-B cells neutralizes CBEs, allowing DJH-RC-bound RAG to scan the VH domain and perform VH-to-DJH rearrangements. To elucidate potential roles of IGCR1-based CBEs and 3'Igh-CBEs in regulating RAG-scanning and elucidate the mechanism of the ordered transition from D-to-JH to VH-to-DJH recombination, we tested effects of inverting and/or deleting IGCR1 or 3'Igh-CBEs in mice and/or progenitor-B cell lines. These studies revealed that normal IGCR1 CBE orientation augments RAG-scanning impediment activity and suggest that 3'Igh-CBEs reinforce ability of the RC to function as a dynamic loop extrusion impediment to promote optimal RAG scanning activity. Finally, our findings indicate that ordered V(D)J recombination can be explained by a gradual WAPL downregulation mechanism in progenitor-B cells as opposed to a strict developmental switch.


Asunto(s)
Secuencias Reguladoras de Ácidos Nucleicos , Recombinación V(D)J , Animales , Ratones , Recombinación V(D)J/genética , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/metabolismo , Células Precursoras de Linfocitos B/metabolismo , Cromatina/metabolismo
10.
Proc Natl Acad Sci U S A ; 120(14): e2219043120, 2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-36996112

RESUMEN

Despite the various strategies for achieving metal-nitrogen-carbon (M-N-C) single-atom catalysts (SACs) with different microenvironments for electrochemical carbon dioxide reduction reaction (CO2RR), the synthesis-structure-performance correlation remains elusive due to the lack of well-controlled synthetic approaches. Here, we employed Ni nanoparticles as starting materials for the direct synthesis of nickel (Ni) SACs in one spot through harvesting the interaction between metallic Ni and N atoms in the precursor during the chemical vapor deposition growth of hierarchical N-doped graphene fibers. By combining with first-principle calculations, we found that the Ni-N configuration is closely correlated to the N contents in the precursor, in which the acetonitrile with a high N/C ratio favors the formation of Ni-N3, while the pyridine with a low N/C ratio is more likely to promote the evolution of Ni-N2. Moreover, we revealed that the presence of N favors the formation of H-terminated edge of sp2 carbon and consequently leads to the formation of graphene fibers consisting of vertically stacked graphene flakes, instead of the traditional growth of carbon nanotubes on Ni nanoparticles. With a high capability in balancing the *COOH formation and *CO desorption, the as-prepared hierarchical N-doped graphene nanofibers with Ni-N3 sites exhibit a superior CO2RR performance compared to that with Ni-N2 and Ni-N4 ones.

11.
Brief Bioinform ; 24(6)2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37950905

RESUMEN

Cancer genomics is dedicated to elucidating the genes and pathways that contribute to cancer progression and development. Identifying cancer genes (CGs) associated with the initiation and progression of cancer is critical for characterization of molecular-level mechanism in cancer research. In recent years, the growing availability of high-throughput molecular data and advancements in deep learning technologies has enabled the modelling of complex interactions and topological information within genomic data. Nevertheless, because of the limited labelled data, pinpointing CGs from a multitude of potential mutations remains an exceptionally challenging task. To address this, we propose a novel deep learning framework, termed self-supervised masked graph learning (SMG), which comprises SMG reconstruction (pretext task) and task-specific fine-tuning (downstream task). In the pretext task, the nodes of multi-omic featured protein-protein interaction (PPI) networks are randomly substituted with a defined mask token. The PPI networks are then reconstructed using the graph neural network (GNN)-based autoencoder, which explores the node correlations in a self-prediction manner. In the downstream tasks, the pre-trained GNN encoder embeds the input networks into feature graphs, whereas a task-specific layer proceeds with the final prediction. To assess the performance of the proposed SMG method, benchmarking experiments are performed on three node-level tasks (identification of CGs, essential genes and healthy driver genes) and one graph-level task (identification of disease subnetwork) across eight PPI networks. Benchmarking experiments and performance comparison with existing state-of-the-art methods demonstrate the superiority of SMG on multi-omic feature engineering.


Asunto(s)
Neoplasias , Oncogenes , Mutación , Benchmarking , Genes Esenciales , Genómica , Neoplasias/genética
12.
Nat Mater ; 23(3): 331-338, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37537355

RESUMEN

The properties of two-dimensional (2D) van der Waals materials can be tuned through nanostructuring or controlled layer stacking, where interlayer hybridization induces exotic electronic states and transport phenomena. Here we describe a viable approach and underlying mechanism for the assisted self-assembly of twisted layer graphene. The process, which can be implemented in standard chemical vapour deposition growth, is best described by analogy to origami and kirigami with paper. It involves the controlled induction of wrinkle formation in single-layer graphene with subsequent wrinkle folding, tearing and re-growth. Inherent to the process is the formation of intertwined graphene spirals and conversion of the chiral angle of 1D wrinkles into a 2D twist angle of a 3D superlattice. The approach can be extended to other foldable 2D materials and facilitates the production of miniaturized electronic components, including capacitors, resistors, inductors and superconductors.

13.
J Cell Mol Med ; 28(16): e70014, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39153211

RESUMEN

Anaplastic thyroid cancer (ATC), an aggressive malignancy with virtually 100% disease-specific mortality, has long posed a formidable challenge in oncology due to its resistance to conventional treatments and the severe side effects associated with current regimens such as doxorubicin chemotherapy. Consequently, there was urgent need to identify novel candidate compounds that could provide innovative therapeutic strategies for ATC. Ophiopogonin D' (OPD'), a triterpenoid saponin extracted, yet its roles in ATC has not been reported. Our data demonstrated that OPD' potently inhibited proliferation and metastasis of ATC cells, promoting cell cycle arrest and apoptosis. Remarkably, OPD' impeded growth and metastasis of ATC in vitro and in vivo, displaying an encouraging safety profile. Regulator of G-protein signalling 4 (RGS4) expression was significantly up-regulated in ATC compared to normal tissues, and this upregulation was suppressed by OPD' treatment. Mechanistically, we elucidated that the transcription factor JUN bound to the RGS4 promoter, driving its transactivation. However, OPD' interacted with JUN, attenuating its transcriptional activity and thereby disrupting RGS4 overexpression. In summary, our research revealed that OPD' bound with JUN, which in turn resulted in the suppression of transcriptional activation of RGS4, thereby eliciting cell cycle arrest and apoptosis in ATC cells. These findings could offer promise in the development of high-quality candidate compounds for treatment in ATC.


Asunto(s)
Apoptosis , Proliferación Celular , Proteínas RGS , Saponinas , Transducción de Señal , Espirostanos , Carcinoma Anaplásico de Tiroides , Humanos , Carcinoma Anaplásico de Tiroides/tratamiento farmacológico , Carcinoma Anaplásico de Tiroides/metabolismo , Carcinoma Anaplásico de Tiroides/patología , Saponinas/farmacología , Proteínas RGS/metabolismo , Proteínas RGS/genética , Proliferación Celular/efectos de los fármacos , Animales , Línea Celular Tumoral , Transducción de Señal/efectos de los fármacos , Apoptosis/efectos de los fármacos , Espirostanos/farmacología , Ratones , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proteínas Proto-Oncogénicas c-jun/metabolismo , Ratones Desnudos , Neoplasias de la Tiroides/tratamiento farmacológico , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/genética , Ensayos Antitumor por Modelo de Xenoinjerto , Metástasis de la Neoplasia
14.
J Cell Mol Med ; 28(7): e18182, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38498903

RESUMEN

Chromosome instability (CIN) is a common contributor driving the formation and progression of anaplastic thyroid cancer (ATC), but its mechanism remains unclear. The BUB1 mitotic checkpoint serine/threonine kinase (BUB1) is responsible for the alignment of mitotic chromosomes, which has not been thoroughly studied in ATC. Our research demonstrated that BUB1 was remarkably upregulated and closely related to worse progression-free survival. Knockdown of BUB1 attenuated cell viability, invasion, migration and induced cell cycle arrests, whereas overexpression of BUB1 promoted the cell cycle progression of papillary thyroid cancer cells. BUB1 knockdown remarkably repressed tumour growth and tumour formation of nude mice with ATC xenografts and suppressed tumour metastasis in a zebrafish xenograft model. Inhibition of BUB1 by its inhibitor BAY-1816032 also exhibited considerable anti-tumour activity. Further studies showed that enforced expression of BUB1 evoked CIN in ATC cells. BUB1 induced CIN through phosphorylation of KIF14 at serine1292 (Ser1292 ). Overexpression of the KIF14ΔSer1292 mutant was unable to facilitate the aggressiveness of ATC cells when compared with that of the wild type. Collectively, these findings demonstrate that the BUB1/KIF14 complex drives the aggressiveness of ATC by inducing CIN.


Asunto(s)
Carcinoma Anaplásico de Tiroides , Neoplasias de la Tiroides , Animales , Ratones , Humanos , Carcinoma Anaplásico de Tiroides/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Ratones Desnudos , Pez Cebra/metabolismo , Inestabilidad Cromosómica , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Línea Celular Tumoral , Proteínas Oncogénicas/genética , Cinesinas/genética
15.
BMC Genomics ; 25(1): 138, 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38310206

RESUMEN

BACKGROUND: Spermatogonial stem cells (SSCs) are the foundation cells for continual spermatogenesis and germline regeneration in mammals. SSC activities reside in the undifferentiated spermatogonial population, and currently, the molecular identities of SSCs and their committed progenitors remain unclear. RESULTS: We performed single-cell transcriptome analysis on isolated undifferentiated spermatogonia from mice to decipher the molecular signatures of SSC fate transitions. Through comprehensive analysis, we delineated the developmental trajectory and identified candidate transcription factors (TFs) involved in the fate transitions of SSCs and their progenitors in distinct states. Specifically, we characterized the Asingle spermatogonial subtype marked by the expression of Eomes. Eomes+ cells contained enriched transplantable SSCs, and more than 90% of the cells remained in the quiescent state. Conditional deletion of Eomes in the germline did not impact steady-state spermatogenesis but enhanced SSC regeneration. Forced expression of Eomes in spermatogenic cells disrupted spermatogenesis mainly by affecting the cell cycle progression of undifferentiated spermatogonia. After injury, Eomes+ cells re-enter the cell cycle and divide to expand the SSC pool. Eomes+ cells consisted of 7 different subsets of cells at single-cell resolution, and genes enriched in glycolysis/gluconeogenesis and the PI3/Akt signaling pathway participated in the SSC regeneration process. CONCLUSIONS: In this study, we explored the molecular characteristics and critical regulators of subpopulations of undifferentiated spermatogonia. The findings of the present study described a quiescent SSC subpopulation, Eomes+ spermatogonia, and provided a dynamic transcriptional map of SSC fate determination.


Asunto(s)
Análisis de Expresión Génica de una Sola Célula , Testículo , Masculino , Animales , Ratones , Testículo/metabolismo , Espermatogonias , Espermatogénesis/genética , Células Madre , Diferenciación Celular/genética , Mamíferos/genética
16.
Int J Cancer ; 155(1): 71-80, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429859

RESUMEN

Prostate cancer has high heritability. Healthy lifestyle has been associated with lower lethal prostate cancer risk among men at increased genetic susceptibility, but the role of healthy dietary patterns remains unknown. We prospectively followed 10,269 genotyped men in the Health Professionals Follow-up Study (1993-2019). Genetic risk was quantified using an established polygenic risk score (PRS). Five dietary patterns were investigated: healthy eating index, Mediterranean, diabetes risk-reducing, hyperinsulinemic and inflammatory diet. Overall and lethal prostate cancer rates (metastatic disease/prostate cancer-specific death) were analyzed using multivariable Cox proportional hazards models. During 26 years of follow-up, 2133 overall and 253 lethal prostate cancer events were documented. In the highest PRS quartile, higher adherence to a diabetes risk-reducing diet was associated with lower rates of overall (top vs. bottom quintile HR [95% CI], 0.74 [0.58-0.94]) and lethal prostate cancer (0.43 [0.21-0.88]). A low insulinemic diet was associated with similar lower rates (overall, 0.76 [0.60-0.95]; lethal, 0.46 [0.23-0.94]). Other dietary patterns showed weaker, but similar associations. In the highest PRS quartile, men with healthy lifestyles based on body weight, physical activity, and low insulinemic diet had a substantially lower rate (0.26 [0.13-0.49]) of lethal prostate cancer compared with men with unhealthy lifestyles, translating to a lifetime risk of 3.4% (95% CI, 2.3%-5.0%) among those with healthy lifestyles and 9.5% (5.3%-16.7%) among those with unhealthy lifestyles. Our findings indicate that lifestyle modifications lowering insulin resistance and chronic hyperinsulinemia could be relevant in preventing aggressive prostate cancer among men genetically predisposed to prostate cancer.


Asunto(s)
Dieta Saludable , Predisposición Genética a la Enfermedad , Neoplasias de la Próstata , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Dieta Mediterránea , Estudios de Seguimiento , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/epidemiología , Factores de Riesgo
17.
Int J Cancer ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38985095

RESUMEN

Exposure to ambient ozone (O3) is linked to increased mortality risks from various diseases, but epidemiological investigations delving into its potential implications for cancer mortality are limited. We aimed to examine the association between short-term O3 exposure and site-specific cancer mortality and investigate vulnerable subgroups in Brazil. In total 3,459,826 cancer death records from 5570 Brazilian municipalities between 2000 and 2019, were included. Municipal average daily O3 concentration was calculated from a global estimation at 0.25°×0.25° spatial resolution. The time-stratified case-crossover design was applied to assess the O3-cancer mortality association. Subgroup analyses by age, sex, season, time-period, region, urban hierarchy, climate classification, quantiles of GDP per capita and illiteracy rates were performed. A linear and non-threshold exposure-response relationship was observed for short-term exposure to O3 with cancer mortality, with a 1.00% (95% CI: 0.79%-1.20%) increase in all-cancer mortality risks for each 10-µg/m3 increment of three-day average O3. Kidney cancer was most strongly with O3 exposure, followed by cancers of the prostate, stomach, breast, lymphoma, brain and lung. The associated cancer risks were relatively higher in the warm season and in southern Brazil, with a decreasing trend over time. When restricting O3 concentration to the national minimum value during 2000-2019, a total of 147,074 (116,690-177,451) cancer deaths could be avoided in Brazil, which included 17,836 (7014-28,653) lung cancer deaths. Notably, these associations persisted despite observed adaptation within the Brazilian population, highlighting the need for a focus on incorporating specific measures to mitigate O3 exposure into cancer care recommendations.

18.
PLoS Med ; 21(1): e1004341, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38252630

RESUMEN

BACKGROUND: More intense tropical cyclones (TCs) are expected in the future under a warming climate scenario, but little is known about their mortality effect pattern across countries and over decades. We aim to evaluate the TC-specific mortality risks, periods of concern (POC) and characterize the spatiotemporal pattern and exposure-response (ER) relationships on a multicountry scale. METHODS AND FINDINGS: Daily all-cause, cardiovascular, and respiratory mortality among the general population were collected from 494 locations in 18 countries or territories during 1980 to 2019. Daily TC exposures were defined when the maximum sustained windspeed associated with a TC was ≥34 knots using a parametric wind field model at a 0.5° × 0.5° resolution. We first estimated the TC-specific mortality risks and POC using an advanced flexible statistical framework of mixed Poisson model, accounting for the population changes, natural variation, seasonal and day of the week effects. Then, a mixed meta-regression model was used to pool the TC-specific mortality risks to estimate the overall and country-specific ER relationships of TC characteristics (windspeed, rainfall, and year) with mortality. Overall, 47.7 million all-cause, 15.5 million cardiovascular, and 4.9 million respiratory deaths and 382 TCs were included in our analyses. An overall average POC of around 20 days was observed for TC-related all-cause and cardiopulmonary mortality, with relatively longer POC for the United States of America, Brazil, and Taiwan (>30 days). The TC-specific relative risks (RR) varied substantially, ranging from 1.04 to 1.42, 1.07 to 1.77, and 1.12 to 1.92 among the top 100 TCs with highest RRs for all-cause, cardiovascular, and respiratory mortality, respectively. At country level, relatively higher TC-related mortality risks were observed in Guatemala, Brazil, and New Zealand for all-cause, cardiovascular, and respiratory mortality, respectively. We found an overall monotonically increasing and approximately linear ER curve of TC-related maximum sustained windspeed and cumulative rainfall with mortality, with heterogeneous patterns across countries and regions. The TC-related mortality risks were generally decreasing from 1980 to 2019, especially for the Philippines, Taiwan, and the USA, whereas potentially increasing trends in TC-related all-cause and cardiovascular mortality risks were observed for Japan. CONCLUSIONS: The TC mortality risks and POC varied greatly across TC events, locations, and countries. To minimize the TC-related health burdens, targeted strategies are particularly needed for different countries and regions, integrating epidemiological evidence on region-specific POC and ER curves that consider across-TC variability.


Asunto(s)
Tormentas Ciclónicas , Enfermedades Respiratorias , Humanos , Estados Unidos , Clima , Brasil , Japón
19.
Cancer ; 130(12): 2169-2179, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38319287

RESUMEN

BACKGROUND: Use of multivitamin supplements has been associated with lower incidence of colorectal cancer (CRC). However, its influence on CRC survival remains unknown. METHODS: Among 2424 patients with stage I-III CRC who provided detailed information about multivitamin supplements in the Nurses' Health Study and Health Professionals Follow-up Study, the authors calculated multivariable hazard ratios (HRs) of multivitamin supplements for all-cause and CRC-specific mortality according to post-diagnostic use and dose of multivitamin supplements. RESULTS: During a median follow-up of 11 years, the authors documented 1512 deaths, among which 343 were of CRC. Compared to non-users, post-diagnostic users of multivitamin supplements at a dose of 3-5 tablets/week had lower CRC-specific mortality (HR, 0.55; 95% confidence interval [CI], 0.36-0.83, p = .005), and post-diagnostic users at doses of 3-5 and 6-9 tablets/week had lower all-cause mortality (HR, 0.81; 95% CI, 0.67-0.99, p = .04; HR, 0.79; 95% CI, 0.70-0.88), p < .001). The dose-response analysis showed a curvilinear relationship for both CRC-specific (pnonlinearity < .001) and all-cause mortality (pnonlinearity = .004), with the maximum risk reduction observed at 3-5 tablets/week and no further reduction at higher doses. Compared to non-users in both pre- and post-diagnosis periods, new post-diagnostic users at dose of <10 tablets/week had a lower all-cause mortality (HR, 0.81; 95% CI, 0.71-0.94, p = .005), whereas new users at a dose of ≥10 tablets/week (HR, 1.58; 95% CI, 1.07-2.33) and discontinued users (HR, 1.35; 95% CI, 1.14-1.59) had a higher risk of mortality. CONCLUSIONS: Use of multivitamin supplements at a moderate dose after a diagnosis of nonmetastatic CRC is associated with lower CRC-specific and overall mortality, whereas a high dose (≥10 tablets/week) use is associated with higher CRC-specific mortality.


Asunto(s)
Neoplasias Colorrectales , Suplementos Dietéticos , Vitaminas , Humanos , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/diagnóstico , Femenino , Vitaminas/administración & dosificación , Estudios Prospectivos , Masculino , Persona de Mediana Edad , Anciano , Adulto , Estudios de Seguimiento , Modelos de Riesgos Proporcionales
20.
Br J Cancer ; 130(10): 1709-1715, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38491175

RESUMEN

BACKGROUND: Multivitamin use is common among cancer patients. Whether post-diagnostic multivitamin supplementation is beneficial for prostate cancer survival is largely unknown, and some evidence even suggests potential harm. METHODS: We prospectively assessed post-diagnostic multivitamin use in relation to prostate cancer survival among 4756 men with nonmetastatic prostate cancer at diagnosis in the Health Professionals Follow-up Study (1986-2016). Cox regression models were used to evaluate the association between post-diagnostic multivitamin use and frequency and risk of lethal prostate cancer (distant metastases or prostate cancer-specific death) and all-cause mortality. RESULTS: We observed 438 lethal prostate cancer and 2609 deaths during a median follow-up of 11 years. Compared to non-users, post-diagnostic multivitamin use was not associated with risk of lethal prostate cancer (HR [95% CI], 0.98 [0.74-1.30]) or all-cause mortality (1.00 [0.88-1.12]), after adjustment for potential confounders. Similarly, null associations were observed across various categories of use frequency. Compared to non-users, men who used multivitamins regularly (6-9 tablets/week) after cancer diagnosis had similar risk of lethal prostate cancer (0.96 [0.72-1.28]) and all-cause mortality (0.99 [0.88-1.12]). CONCLUSIONS: We found no evidence that post-diagnostic multivitamin use among men with nonmetastatic prostate cancer was associated with better or worse survival in a well-nourished population.


Asunto(s)
Neoplasias de la Próstata , Vitaminas , Humanos , Masculino , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/diagnóstico , Vitaminas/administración & dosificación , Vitaminas/uso terapéutico , Anciano , Persona de Mediana Edad , Estudios Prospectivos , Estudios de Seguimiento , Suplementos Dietéticos , Adulto , Modelos de Riesgos Proporcionales
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