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Zhang, S.

Publications and source records attributed to Zhang, S..

At least 541 records · Page 30Linked to original sources

Evolutionary analysis of paired box gene family and biological function exploration of Lr.Pax7 in lamprey (Lethenteron reissneri)

The Pax(paired box)gene family comprises highly conserved transcription factors that play a crucial regulatory role in embryonic development, tissue morphogenesis, and cell differentiation. The gene family comprises of nine members, namely Pax1 to Pax9, each exhibiting distinct functionalities and expression patterns. Among the members of the Pax family, Pax7 is particularly involved in key regulatory functions related to skeletal muscle development and satellite cell biology in vertebrates. However, the precise role of Pax7 and its downstream targets in jawless vertebrates such as lamprey remains relatively understudied. Therefore, investigating the expression and function of lampreys Pax genes holds significant value as a model organism for understanding developmental processes, evolution, and interactions with other vertebrates. In this study, we identified Pax7 in Lethentero reissneri and multiple bioinformatics analyses suggested that it may represent the ancestral gene of the Pax7 shared among higher vertebrates. To further elucidate the function and regulatory mechanism of Pax7, we performed transcriptome sequencing analysis after silencing Lr.Pax7 expression which revealed alterations in metabolic processes along with associated genes(Plcy,Jagged2,Hes,Myod,Frizzled2,etc) involved in various immune pathways(Notch, Wnt, IL-17, TNF, etc), myogenesis process, adipocyte formation process consistent with those observed in higher vertebrates. Comparative studies between lamprey and high vertebrates could provide valuable insight into understanding the functional role of Pax7 and its downstream targets across diverse biological process as well as disease states.

evolutionary biology↗

High-Resolution Epitope Mapping for Glycosylated Antigens: Pembrolizumab-PD1 as a Case Study

High-resolution binding site mapping is important for in-depth activity assessment of new therapeutics including AI-designed antibodies. However, complex protein targets such as glycosylated antigens are challenging for many methods including crystallography. PD1 is a highly glycosylated antigen, and with the traditional HDX-MS method, only 51% sequence coverage could be obtained with multiple epitope residues undetected for Pembrolizumab. By implementing glyco-peptide detection, subzero temperature LC-MS and electron based MSMS fragmentation, the new HDX FineMapping methodology enabled 100% sequence coverage and complete epitope characterization for the Pembrolizumab-PD1 system, with amino acid level resolution. Furthermore, HDX FineMapping detects binding epitopes directly in solution, without any mutation or modification to either the antigen or the antibody. The amino acid level resolution combined with low cost, minimal sample consumption, fast turnaround time, and no need of mutant library or crystallization makes it a competitive methodology for binding mode validation of AI-designed therapeutics.

biophysics↗

Impacts of global warming on fertility of male fishes: evidence from meta-analysis of temperature effects on spermatozoa motility

Studies have demonstrated adverse effects of global warming on aquatic ecosystems from the abiotic to the biotic level. In the present work, a meta-analysis study was conducted to elucidate the effects of global warming on spermatozoa functions, which are key determinants of male fertility. We recruited 245 data records from a pool of empirical studies, which includes 20 studies spanning 20 cold- and warm-water fish species, to identify the effects of increased water temperature (IWT) on determinants of sperm fertility in fishes. Data were systematically re-processed and re-analyzed to determine the overall effects of IWT on sperm kinetics such as motility (MOT), duration of motility (DSM), curvilinear velocity (VCL), rectilinear velocity (VSL) and average path velocity (VAP), as well as on enzymatic activities for energy supply (EAES) and antioxidant enzyme activity (ANEA). The standardized mean difference was calculated for each study, with positive values indicating higher performance under IWT. Results showed that (a) the overall effect size for MOT was more negative in cold-water fishes (-1.22) than in warm-water fishes (-0.98). (b) Each 1 {degrees}C increase in the activation medium reduced MOT by 1.30% (cold-water fishes) and 3.47% (warm-water fishes). (c) The IWT negatively affected DSM, decreasing it by 10 s (cold-water species) and 5.64 s (warm-water species) per degree of IWT. (d) Spermatozoa velocity (VCL and VSL) was increased by IWT in warm-water species. In conclusion, this study shows that IWT negatively affects sperm motility kinetics, suggesting an impact of global warming on fish reproduction.

cell biology↗

Tumor suppressor p73 transcriptionally regulates c-FLIP to impede its priming of extrinsic apoptosis while a switcher compound degrades c-FLIP protein

The tumor suppressor p73 is a member of the p53 family and transcriptionally activates multiple p53-targets involved in cell cycle regulation and apoptosis. In addition to pro- apoptotic signaling, outcomes of p73 activation include cell survival signals. Thus, p73 activity and targets may provide insight in cell fate outcomes between cell survival and apoptosis following cellular stress. We report that cellular FLICE inhibitory protein (c- FLIP), a master antiapoptotic factor, is a transcriptional target of p73. The activation of p73 ( and {beta} isoforms) transcriptionally upregulates c-FLIP-L/S expression in cancer cells. The cell fate decision following p73 activation is determined by the adjustment of the balance of outcomes of p73 activation between p73-induced pro-apoptotic signaling and c-FLIP-L/S expression in cancer cells. p73 primes extrinsic apoptosis via an autocrine death ligand-DR5 axis, and the priming appears to be titrated at the level of c-FLIP-L/S. The p73-upregulation of c-FLIP-L/S increases the threshold of extrinsic apoptosis. Cells with poor priming levels convert to cell cycle arrest and survival. Depletion of c-FLIP-L/S increases the p73-priming levels towards extrinsic apoptosis and sensitizes cancer cells to p73-primed extrinsic apoptosis. We further identified a small-molecule CB-7587351 ("switcher compound") that alters p73 activation outcomes through c-FLIP-L/S protein degradation. Therapeutic activation of p73 can restore p53- signaling in mutant p53-expressing cancer cells effectively bypassing the p53 deficiency in cancer cells. Our discovery of p73 transcriptional upregulation of c-FLIP provides a promising strategy for depleting c-FLIP to improve antitumor efficacy of p73-targeting cancer therapy for p53-mutant tumors.

cancer biology↗

PSMA-Guided PROTAC Degraders for Tumor-Specific Protein Degradation in Prostate Cancer

PROTACs, degrading target protein to treat diseases, represent a highly promising drug design strategy. However, the degradation of target proteins by PROTACs in non-disease tissues may lead to systemic toxicity. Herein, capitalizing on the characteristic overexpression of PSMA in prostate cancer tumor tissues, we devised a PSMA-guided PROTACs specific targeting to prostate cancer. By conjugating AR degraders and BET degraders separately with PSMA ligands via cleavable linkers, two classes of PSMA-guided PROTACs were obtained. In vitro experiments demonstrated that PSMA-guided PROTAC molecules selectively degraded target proteins in PSMA-overexpressing prostate cancer cells, without affecting target proteins in non-PSMA-overexpressing cells. In vivo studies revealed that compared to conventional PROTACs, PSMA-guided PROTACs enhanced drug exposure in prostate cancer tumor tissues, prolonged half-life, and consequently achieved stronger and more sustained therapeutic effects. The PSMA-guided PROTAC strategy provides a novel avenue for disease tissue-specific PROTAC research, holding significant implications for targeted therapy in prostate cancer.

cancer biology↗

The robust, high-throughput, and temporally regulated roxCre and loxCre reporting systems for genetic modifications in vivo

Cre-loxP technology, a cornerstone in fate mapping and in vivo gene function studies, faces challenges in achieving precise and efficient conditional mutagenesis through inducible systems. This study introduces two innovative genetic tools designed to overcome these limitations. The first, roxCre, enables DreER-mediated Cre release, paving the way for intersectional genetic manipulation that permits increased precision and efficiency. The second, loxCre, facilitates conditional gene targeting by allowing CreER lines to induce Cre expression with significantly enhanced efficiency. These tools incorporate a fluorescent reporter for genetic lineage tracing, simultaneously revealing efficient gene knockout in cells marked by the reporter. These strategies hold great potential for precise and efficient exploration of lineage-specific gene functions, marking a significant advancement in genetic research methodologies.

genetics↗

ITGB6 inhibition stimulates anti-tumor responses in immunocompetent mouse models of head & neck squamous cell carcinoma and pancreatic adenocarcinoma

ITGB6, the gene encoding the {beta}6 subunit of integrin v{beta}6, is a potent prognostic marker across multiple cancer types. As a major activator of latent TGF{beta}, v{beta}6, and consequently, ITGB6, has considerable therapeutic implications due to the immunosuppressive effect that activated TGF{beta} has on the tumor microenvironment. The present study identifies ITGB6 as a potent target for inducing an immune-mediated anti-tumor response. ITGB6 is highly upregulated in various squamous cell carcinomas and pancreatic adenocarcinomas, allowing it to disrupt tumor-immune cell signaling, while avoiding the widespread side-effects of systemic TGF{beta} inhibition. Genetic knockout of ITGB6 in heterotopically injected head and neck squamous cell carcinoma and pancreatic adenocarcinoma cell lines showed markedly reduced tumor progression in immunocompetent mice. Additionally, co-cultures of human squamous cell carcinoma cell lines and human T-cells showed increased T-cell killing upon cancer cell ITGB6 inhibition. Colony formation experiments give further evidence that the reduction in tumor growth observed upon ITGB6 inhibition in vivo is through immunological clearance of cancer cells and not merely through intrinsic factors. Analysis of The Cancer Genome Atlas (TCGA) revealed not only the high prognostic value of ITGB6 on overall survival but also that high ITGB6 expression in patients is often associated with an inferior response to -PD-1 and -PD-L1 immune checkpoint blockade. The potent anti-tumor immune response observed both in vitro and in vivo upon ITGB6 inhibition, combined with our analysis of RNA-seq data from immune checkpoint blockade-treated patients, encourages the development of ITGB6 blockade and immunotherapy combination regimes. Further pre-clinical studies will serve to facilitate the translation of our findings into therapeutic clinical trials of combination therapies for treating immunotherapy-resistant cancers. Visual Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/590156v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@162546aorg.highwire.dtl.DTLVardef@9422d6org.highwire.dtl.DTLVardef@17b4a5eorg.highwire.dtl.DTLVardef@14f903d_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

5'-S-(3-aminophenyl)-5'-thioadenosine, a novel chemoprotective agent for reducing toxic side effects of fluorouracil in treatment of MTAP-deficient cancers

BackgroundNucleobase analogue (NBA) drugs are effective chemotherapeutics, but their clinical use is limited by severe side effects. Compelling evidence suggests the use of S-methyl-5-thioadenosine (MTA) can selectively reduce NBA toxicity on normal tissues while maintaining the efficacy of NBAs on methylthioadenosine phosphorylase (MTAP)-deficient cancers. However, we found that MTA induced hypothermia at its effective dose, limiting its translational potential. We intended to find an MTA analogue that can exert MTA function while minimize the undesired side effects of MTA. Thus, such an analogue can be used in combination with NBAs in selectively targeting MTAP-deficient cancers. MethodsWe screened a library of MTA analogues for the following criteria: 1) being substrates of MTAP; 2) selectively protection on MTAP-expressing cells from NBA toxicity using MTAP-isogenic cell lines; 3) ability to protect the host from NBA toxicity without hypothermic effect; and 4) lack of interference on the tumor-suppressive effect of NBA in mice bearing MTAP-deficient tumors. ResultsWe identified 5-S-(3-aminophenyl)-5-thioadenosine (m-APTA) that did not induce hypothermia at the effective doses. We demonstrated that m-APTA could be converted to adenine by MTAP. Consequently, m-APTA selectively protected mouse hosts from 5-FU-induced toxicity (i.e. anemia); yet it did not interfere with the drug efficacy on MTAP-deficient bladder cancers. In silico docking studies revealed that, unlike MTA, m-APTA interact inefficiently with adenosine A1 receptor, providing a plausible explanation of the superior safety profile of m-APTA. Conclusionm-APTA can significantly improve the translational potential of the NBA toxicity reduction strategy in selectively targeting MTAP-deficient cancers.

cancer biology↗

SARS-CoV-2 spike S2 subunit inhibits p53 activation of p21(WAF1), TRAIL Death Receptor DR5 and MDM2 proteins in cancer cells

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and COVID-19 infection has led to worsened outcomes for patients with cancer. SARS-CoV-2 spike protein mediates host cell infection and cell-cell fusion that causes stabilization of tumor suppressor p53 protein. In-silico analysis previously suggested that SARS-CoV-2 spike interacts with p53 directly but this putative interaction has not been demonstrated in cells. We examined the interaction between SARS-CoV-2 spike, p53 and MDM2 (E3 ligase, which mediates p53 degradation) in cancer cells using an immunoprecipitation assay. We observed that SARS-CoV-2 spike protein interrupts p53-MDM2 protein interaction but did not detect SARS-CoV-2 spike bound with p53 protein in the cancer cells. We further observed that SARS-CoV-2 spike suppresses p53 transcriptional activity in cancer cells including after nutlin exposure of wild-type p53-, spike S2-expressing tumor cells and inhibits chemotherapy-induced p53 gene activation of p21(WAF1), TRAIL Death Receptor DR5 and MDM2. The suppressive effect of SARS-CoV-2 spike on p53-dependent gene activation provides a potential molecular mechanism by which SARS-CoV-2 infection may impact tumorigenesis, tumor progression and chemotherapy sensitivity. In fact, cisplatin-treated tumor cells expressing spike S2 were found to have increased cell viability as compared to control cells. Further observations on {gamma}-H2AX expression in spike S2-expressing cells treated with cisplatin may indicate altered DNA damage sensing in the DNA damage response pathway. The preliminary observations reported here warrant further studies to unravel the impact of SARS-CoV-2 and its various encoded proteins including spike on pathways of tumorigenesis and response to cancer therapeutics.

cancer biology↗

Identify compound-protein interaction with knowledge graph embedding of perturbation transcriptomics

The emergence of perturbation transcriptomics provides a new perspective and opportunity for drug discovery, but existing analysis methods suffer from inadequate performance and limited applicability. In this work, we present PertKGE, a method designed to improve compound-protein interaction with knowledge graph embedding of perturbation transcriptomics. PertKGE incorporates diverse regulatory elements and accounts for multi-level regulatory events within biological systems, leading to significant improvements compared to existing baselines in two critical "cold-start" settings: inferring binding targets for new compounds and conducting virtual ligand screening for new targets. We further demonstrate the pivotal role of incorporating multi- level regulatory events in alleviating dataset bias. Notably, it enables the identification of ectonucleotide pyrophosphatase/phosphodiesterase-1 as the target responsible for the unique anti- tumor immunotherapy effect of tankyrase inhibitor K-756, and the discovery of five novel hits targeting the emerging cancer therapeutic target, aldehyde dehydrogenase 1B1, with a remarkable hit rate of 10.2%. These findings highlight the potential of PertKGE to accelerate drug discovery by elucidating mechanisms of action and identifying novel therapeutic compounds.

bioinformatics↗

The G1/S transition in mammalian stem cells in vivo is autonomously regulated by cell size

Cell growth and division must be coordinated to maintain a stable cell size, but how this coordination is implemented in multicellular tissues remains unclear. In unicellular eukaryotes, autonomous cell size control mechanisms couple cell growth and division with little extracellular input. However, in multicellular tissues we do not know if autonomous cell size control mechanisms operate the same way or whether cell growth and cell cycle progression are separately controlled by cell-extrinsic signals. Here, we address this question by tracking single epidermal stem cells growing in adult mice. We find that a cell-autonomous size control mechanism, dependent on the RB pathway, sets the timing of S phase entry based on the cells current size. Cell-extrinsic variations in the cellular microenvironment affect cell growth rates but not this autonomous coupling. Our work reassesses long-standing models of cell cycle regulation within complex metazoan tissues and identifies cell-autonomous size control as a critical mechanism regulating cell divisions in vivo and thereby a major contributor to stem cell heterogeneity.

cell biology↗

The fascinating role of neuropeptide Bursicon and its receptor in shaping insect seasonal polyphenism

Seasonal polyphenism enables organisms to adapt to environmental challenges by increasing phenotypic diversity. Cacopsylla chinensis exhibits remarkable seasonal polyphenism, specifically in the form of summer-form and winter-form, which have distinct morphological phenotypes. Previous research has shown that low temperature and the temperature receptor CcTRPM regulate the transition from summer-form to winter-form in C. chinensis by impacting cuticle content and thickness. However, the underling neuroendocrine regulatory mechanism remains largely unknown. Bursicon, also known as the tanning hormone, is responsible for the hardening and darkening of the insect cuticle. In this study, we report for the first time on the novel function of Bursicon and its receptor in the transition from summer-form to winter-form in C. chinensis. Firstly, we identified CcBurs- and CcBurs-{beta} as two typical subunits of Bursicon in C. chinensis, which were regulated by low temperature (10{degrees}C) and CcTRPM. Subsequently, CcBurs- and CcBurs-{beta} formed a heterodimer that mediated the transition from summer-form to winter-form by influencing the cuticle chitin contents and cuticle thickness. Furthermore, we demonstrated that CcBurs-R acts as the Bursicon receptor and plays a critical role in the up-stream signaling of the chitin biosyntheis pathway, regulating the transition from summer-form to winter-form. Finally, we discovered that miR-6012 directly targets CcBurs-R, contributing to the regulation of Bursicon signaling in the seasonal polyphenism of C. chinensis. In summary, these findings reveal the novel function of neuroendocrine regulatory mechanism underlying seasonal polyphenism and provide critical insights into insect Bursicon and its receptor.

ecology↗

Comparative genomics of macaques and integrated insights into genetic variation and population history

The crab-eating macaques (Macaca fascicularis) and rhesus macaques (M. mulatta) are widely studied nonhuman primates in biomedical and evolutionary research. Despite their significance, the current understanding of the complex genomic structure in macaques and the differences between species requires substantial improvement. Here, we present a complete genome assembly of a crab-eating macaque and 20 haplotype-resolved macaque assemblies to investigate the complex regions and major genomic differences between species. Segmental duplication in macaques is [~]42% lower, while centromeres are [~]3.7 times longer than those in humans. The characterization of [~]2 Mbp fixed genetic variants and [~]240 Mbp complex loci highlights potential associations with metabolic differences between the two macaque species (e.g., CYP2C76 and EHBP1L1). Additionally, hundreds of alternative splicing differences show post-transcriptional regulation divergence between these two species (e.g., PNPO). We also characterize 91 large-scale genomic differences between macaques and humans at a single-base-pair resolution and highlight their impact on gene regulation in primate evolution (e.g., FOLH1 and PIEZO2). Finally, population genetics recapitulates macaque speciation and selective sweeps, highlighting potential genetic basis of reproduction and tail phenotype differences (e.g., STAB1, SEMA3F, and HOXD13). In summary, the integrated analysis of genetic variation and population genetics in macaques greatly enhances our comprehension of lineage-specific phenotypes, adaptation, and primate evolution, thereby improving their biomedical applications in human diseases.

genomics↗

Redefining the Game: MVAE-DFDPnet's Low-Dimensional Embeddings for Superior Drug-Protein Interaction Predictions

Precisely predicting drug-protein interactions (DPIs) is pivotal for drug discovery and advancing precision medicine. A significant challenge in this domain is the high-dimensional and heterogeneous data characterizing drug and protein attributes, along with their intricate interactions. In our study, we introduce a novel deep learning architecture: the Multi-view Variational Auto-Encoder embedded within a cascade Deep Forest (MVAE-DFDPnet). This framework adeptly learns ultra-low-dimensional embedding for drugs and proteins. Notably, our t-SNE analysis reveals that two-dimensional embedding can clearly define clusters corresponding to diverse drug classes and protein families. These ultra-low-dimensional embedding likely contribute to the enhanced robustness and generalizability of our MVAE-DFDPnet. Impressively, our model surpasses current leading methods on benchmark datasets, functioning in significantly reduced dimensional spaces. The models resilience is further evidenced by its sustained accuracy in predicting interactions involving novel drugs, proteins, and drug classes. Additionally, we have corroborated several newly identified DPIs with experimental evidence from the scientific literature. The code used to generate and analyze these results can be accessed from https://github.com/Macau-LYXia/MVAE-DFDPnet-V2.

bioinformatics↗

A multi-track landscape of haematopoiesis informed by cellular barcoding and agent-based modelling

In classic ball-and-stick models of haematopoiesis the implicit assumption is that all cells within each defined stem or progenitor cell population are equivalent in their fate. Instead, more recent models suggest a haematopoietic stem and progenitor cell (HSPC) continuum of lineage bias and commitment, which is largely inferred through snapshot analysis of single cell gene expression or clonal fate. However, the dynamic assessment of lineage commitment of specific HSPC populations and their clonal output over time in vivo is still lacking but is essential to fully inform accurate models of haematopoiesis. Here, using cellular barcoding we compare the single cell output of long-term haematopoietic stem cells (LT-HSCs), short-term HSCs (ST-HSCs), multipotent progenitors (LMPPs), common myeloid progenitors (CMPs), common lymphoid progenitors (CLPs), and macrophage/dendritic cell progenitors (MDPs). Each population was assessed for their output to multiple haematopoietic cell types spanning a subset of time points from 9 to 112 days of haematopoiesis after transplantation. These analyses revealed a wide range of clonal fate patterns that were inconsistent with their eponymous labels, i.e. stem and multipotent progenitors were rarely multi- or equipotent, and common progenitors were often highly restricted in their fate. To better describe how these clonal patterns integrate into a revised landscape, a novel agent-based mathematical modelling approach that explicitly accounts for haematopoiesis at a clonal level was developed to allow the simulation of growth, timing and branching of clonal trajectories that underlie the process. Rather than a continuum, the proposed model is suggestive of multiple tracks down which clonal trajectories progress, and where fate can branch to a track of lower potency at multiple points down the entire cascade of haematopoiesis. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=101 SRC="FIGDIR/small/587126v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@b09137org.highwire.dtl.DTLVardef@de064org.highwire.dtl.DTLVardef@10705e3org.highwire.dtl.DTLVardef@139b6f_HPS_FORMAT_FIGEXP M_FIG C_FIG In a multi-track model, while some HSPCs are multipotent and branch into daughters with committed fate (left trajectory), other HSPCs may already committed or biased to a certain lineage such that their daughters inherit and maintain it in subsequent divisions during haematopoiesis. However, this commitment/fate bias is not evident through current phenotypic definitions of HSPC subsets (background colour) but occurs through putative expression of transcription factors, epigenetic programming or other factor that is currently unresolved (as indicated by the coloured fate potential triangles inside cells).

immunology↗

ACSS2 upregulation enhances neuronal resilience to aging and tau-associated neurodegeneration

Epigenetic mechanisms, including histone acetylation, are pivotal for learning and memory, with a role in neuronal function in Alzheimers disease and Related Dementia (ADRD). Acetyl-CoA synthetase 2 (ACSS2), an enzyme that generates acetyl-CoA, is central to histone acetylation and gene regulation, particularly in neurons, due to their unique metabolic demands and postmitotic state. ACSS2 can be recruited to the nucleus and chromatin, locally supplying acetyl-CoA to directly fuel histone acetyltransferase enzymes and key neuronal gene expression. This regulatory mechanism may be a promising target for therapeutic intervention in neurodegenerative diseases. Previously we showed that systemic ACSS2 deletion in mice, although largely normal in physiology, is greatly impaired in memory. Here we investigated whether increasing ACSS2 levels could protect neurons against disease and age-associated cognitive decline. Given the role of tau in ADRD, we used primary hippocampal neurons that mimic the sporadic development of tau pathology and the P301S transgenic mouse model for tau-induced memory decline. Our results show that ACSS2 upregulation mitigates tau-induced transcriptional alterations, enhances neuronal resilience against tau pathology, improves long-term potentiation, and ameliorates memory deficits. Expanding upon these findings, we reveal that increasing histone acetylation through ACSS2 upregulation improves age-associated memory decline. These findings indicate that increasing ACSS2 is highly effective in countering age- and tau-induced transcriptome changes, preserving elevated levels of synaptic genes, and safeguarding synaptic integrity. We thus highlight ACSS2 as a key player in the epigenetic regulation of cognitive aging and ADRD, providing a foundation for targeted therapeutics to enhance brain resilience and function. SummaryACSS2 upregulation protects neurons from disease and age-related decline by enhancing synaptic and longevity gene expression.

neuroscience↗

Mechanical cues of extracellular matrix determines tumor innervation

Peripheral tumors can establish local autonomic and sensory nerve networks, termed as tumor innervation (TIN), to support tumorigenesis and metastasis. While nerve dependence in cancers is well-established, the mechanisms governing TIN remain unclear. Here, we report that extracellular matrix (ECM) stiffness, a major mechanical abnormality in the tumor microenvironment (TME), is an essential contributor of TIN. In preclinical models, reducing lysyl oxidase-mediated ECM crosslinking lowers tissue stiffness and TIN in pancreatic cancer, while inflammation-induced matrix stiffening boosts the hyperinnervation of the pancreatic precursor lesions. Mechanistically, {beta}1-containing integrins sense the mechanical cues exerted by ECM stiffness, and the translational co-activator YAP1 acts as an essential nuclear relay to induce the expression of neurotropic genes, particularly brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). 3D imaging of the whole cleared pancreas reveals that blockade of mechanosensor integrin {beta}1 or pharmacological inhibition of the mechanotransducer YAP1 effectively reduces TIN. In clinical settings, tumor samples with a dense, crosslinked, and stiffened ECM exhibit significant TIN. In summary, these findings identify ECM stiffness as an important driver of TIN and suggest that targeting integrin {beta}1/YAP1-dependent mechanotransduction may counteract TIN.

neuroscience↗

SARS-CoV-2 infection activates inflammatory macrophages in vascular immune organoids

SARS-CoV-2 provokes devastating tissue damage by cytokine release syndrome and leads to multi-organ failure. Modeling the process of immune cell activation and subsequent tissue damage is a significant task. Organoids from human tissues advanced our understanding of SARS-CoV-2 infection mechanisms though, they are missing crucial components: immune cells and endothelial cells. This study aims to generate organoids with these components. We established vascular immune organoids from human pluripotent stem cells and examined the effect of SARS-CoV-2 infection. We demonstrated that infections activated inflammatory macrophages. Notably, the upregulation of interferon signaling supports macrophages role in cytokine release syndrome. We propose vascular immune organoids are a useful platform to model and discover factors that ameliorate SARS-CoV-2-mediated cytokine release syndrome.

immunology↗