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1.
World J Gastroenterol ; 30(11): 1609-1620, 2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38617448

ABSTRACT

BACKGROUND: Liver cancer is one of the deadliest malignant tumors worldwide. Immunotherapy has provided hope to patients with advanced liver cancer, but only a small fraction of patients benefit from this treatment due to individual differences. Identifying immune-related gene signatures in liver cancer patients not only aids physicians in cancer diagnosis but also offers personalized treatment strategies, thereby improving patient survival rates. Although several methods have been developed to predict the prognosis and immunotherapeutic efficacy in patients with liver cancer, the impact of cell-cell interactions in the tumor microenvironment has not been adequately considered. AIM: To identify immune-related gene signals for predicting liver cancer prognosis and immunotherapy efficacy. METHODS: Cell grouping and cell-cell communication analysis were performed on single-cell RNA-sequencing data to identify highly active cell groups in immune-related pathways. Highly active immune cells were identified by intersecting the highly active cell groups with B cells and T cells. The significantly differentially expressed genes between highly active immune cells and other cells were subsequently selected as features, and a least absolute shrinkage and selection operator (LASSO) regression model was constructed to screen for diagnostic-related features. Fourteen genes that were selected more than 5 times in 10 LASSO regression experiments were included in a multivariable Cox regression model. Finally, 3 genes (stathmin 1, cofilin 1, and C-C chemokine ligand 5) significantly associated with survival were identified and used to construct an immune-related gene signature. RESULTS: The immune-related gene signature composed of stathmin 1, cofilin 1, and C-C chemokine ligand 5 was identified through cell-cell communication. The effectiveness of the identified gene signature was validated based on experimental results of predictive immunotherapy response, tumor mutation burden analysis, immune cell infiltration analysis, survival analysis, and expression analysis. CONCLUSION: The findings suggest that the identified gene signature may contribute to a deeper understanding of the activity patterns of immune cells in the liver tumor microenvironment, providing insights for personalized treatment strategies.


Subject(s)
Cofilin 1 , Liver Neoplasms , Humans , Ligands , Stathmin , Prognosis , Immunotherapy , Liver Neoplasms/genetics , Liver Neoplasms/therapy , Cell Communication , Chemokines, CC , Tumor Microenvironment/genetics
2.
Int J Mol Sci ; 25(7)2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38612452

ABSTRACT

The tumor microenvironment (TME) plays a critical role in cancerogenesis [...].


Subject(s)
Neoplasms , Humans , Cell Communication , Tumor Microenvironment
3.
Int J Mol Sci ; 25(7)2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38612645

ABSTRACT

Pediatric neoplasms represent a complex group of malignancies that pose unique challenges in terms of diagnosis, treatment, and understanding of the underlying molecular pathogenetic mechanisms. Erythropoietin-producing hepatocellular receptors (EPHs), the largest family of receptor tyrosine kinases and their membrane-tethered ligands, ephrins, orchestrate short-distance cell-cell signaling and are intricately involved in cell-pattern morphogenesis and various developmental processes. Unraveling the role of the EPH/ephrin signaling pathway in the pathophysiology of pediatric neoplasms and its clinical implications can contribute to deciphering the intricate landscape of these malignancies. The bidirectional nature of the EPH/ephrin axis is underscored by emerging evidence revealing its capacity to drive tumorigenesis, fostering cell-cell communication within the tumor microenvironment. In the context of carcinogenesis, the EPH/ephrin signaling pathway prompts a reevaluation of treatment strategies, particularly in pediatric oncology, where the modest progress in survival rates and enduring treatment toxicity necessitate novel approaches. Molecularly targeted agents have emerged as promising alternatives, prompting a shift in focus. Through a nuanced understanding of the pathway's intricacies, we aim to lay the groundwork for personalized diagnostic and therapeutic strategies, ultimately contributing to improved outcomes for young patients grappling with neoplastic challenges.


Subject(s)
Clinical Relevance , Hematologic Neoplasms , Humans , Child , Signal Transduction , Cell Communication , Carcinogenesis , Ephrins , Receptors, Erythropoietin , Tumor Microenvironment
4.
Int J Mol Sci ; 25(7)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38612745

ABSTRACT

Insects heavily rely on the olfactory system for food, mating, and predator evasion. However, the caste-related olfactory differences in Apis cerana, a eusocial insect, remain unclear. To explore the peripheral and primary center of the olfactory system link to the caste dimorphism in A. cerana, transcriptome and immunohistochemistry studies on the odorant receptors (ORs) and architecture of antennal lobes (ALs) were performed on different castes. Through transcriptomesis, we found more olfactory receptor genes in queens and workers than in drones, which were further validated by RT-qPCR, indicating caste dimorphism. Meanwhile, ALs structure, including volume, surface area, and the number of glomeruli, demonstrated a close association with caste dimorphism. Particularly, drones had more macroglomeruli possibly for pheromone recognition. Interestingly, we found that the number of ORs and glomeruli ratio was nearly 1:1. Also, the ORs expression distribution pattern was very similar to the distribution of glomeruli volume. Our results suggest the existence of concurrent plasticity in both the peripheral olfactory system and ALs among different castes of A. cerana, highlighting the role of the olfactory system in labor division in insects.


Subject(s)
Hymenoptera , Receptors, Odorant , Bees/genetics , Animals , Sex Characteristics , Cell Communication , Food , Receptors, Odorant/genetics
5.
Brief Bioinform ; 25(3)2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38605638

ABSTRACT

Recent advances in single-cell RNA sequencing technology have eased analyses of signaling networks of cells. Recently, cell-cell interaction has been studied based on various link prediction approaches on graph-structured data. These approaches have assumptions about the likelihood of node interaction, thus showing high performance for only some specific networks. Subgraph-based methods have solved this problem and outperformed other approaches by extracting local subgraphs from a given network. In this work, we present a novel method, called Subgraph Embedding of Gene expression matrix for prediction of CEll-cell COmmunication (SEGCECO), which uses an attributed graph convolutional neural network to predict cell-cell communication from single-cell RNA-seq data. SEGCECO captures the latent and explicit attributes of undirected, attributed graphs constructed from the gene expression profile of individual cells. High-dimensional and sparse single-cell RNA-seq data make converting the data into a graphical format a daunting task. We successfully overcome this limitation by applying SoptSC, a similarity-based optimization method in which the cell-cell communication network is built using a cell-cell similarity matrix which is learned from gene expression data. We performed experiments on six datasets extracted from the human and mouse pancreas tissue. Our comparative analysis shows that SEGCECO outperforms latent feature-based approaches, and the state-of-the-art method for link prediction, WLNM, with 0.99 ROC and 99% prediction accuracy. The datasets can be found at https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE84133 and the code is publicly available at Github https://github.com/sheenahora/SEGCECO and Code Ocean https://codeocean.com/capsule/8244724/tree.


Subject(s)
Cell Communication , Signal Transduction , Humans , Animals , Mice , Cell Communication/genetics , Learning , Neural Networks, Computer , Gene Expression
6.
Cell ; 187(8): 2010-2028.e30, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38569542

ABSTRACT

Gut inflammation involves contributions from immune and non-immune cells, whose interactions are shaped by the spatial organization of the healthy gut and its remodeling during inflammation. The crosstalk between fibroblasts and immune cells is an important axis in this process, but our understanding has been challenged by incomplete cell-type definition and biogeography. To address this challenge, we used multiplexed error-robust fluorescence in situ hybridization (MERFISH) to profile the expression of 940 genes in 1.35 million cells imaged across the onset and recovery from a mouse colitis model. We identified diverse cell populations, charted their spatial organization, and revealed their polarization or recruitment in inflammation. We found a staged progression of inflammation-associated tissue neighborhoods defined, in part, by multiple inflammation-associated fibroblasts, with unique expression profiles, spatial localization, cell-cell interactions, and healthy fibroblast origins. Similar signatures in ulcerative colitis suggest conserved human processes. Broadly, we provide a framework for understanding inflammation-induced remodeling in the gut and other tissues.


Subject(s)
Colitis, Ulcerative , Colitis , Animals , Humans , Mice , Colitis/metabolism , Colitis/pathology , Colitis, Ulcerative/metabolism , Colitis, Ulcerative/pathology , Fibroblasts/metabolism , Fibroblasts/pathology , In Situ Hybridization, Fluorescence/methods , Inflammation/metabolism , Inflammation/pathology , Cell Communication , Gastrointestinal Tract/metabolism , Gastrointestinal Tract/pathology
7.
Clin Transl Med ; 14(4): e1645, 2024 04.
Article in English | MEDLINE | ID: mdl-38572668

ABSTRACT

BACKGROUND: Breast cancer remains a global health challenge, necessitating innovative therapeutic approaches. Immunomodulation and immunotherapy have emerged as promising strategies for breast cancer treatment. Engineered exosomes are the sort of exosomes modified with surface decoration and internal therapeutic molecules. Through suitable modifications, engineered exosomes exhibit the capability to overcome the limitations associated with traditional therapeutic approaches. This ability opens up novel avenues for the development of more effective, personalized, and minimally invasive interventions. MAIN BODY: In this comprehensive review, we explore the molecular insights and therapeutic potential of engineered exosomes in breast cancer. We discuss the strategies employed for exosome engineering and delve into their molecular mechanisms in reshaping the immune microenvironment of breast cancer. CONCLUSIONS: By elucidating the contribution of engineered exosomes to breast cancer immunomodulation, this review underscores the transformative potential of this emerging field for improving breast cancer therapy. HIGHLIGHTS: Surface modification of exosomes can improve the targeting specificity. The engineered exosome-loaded immunomodulatory cargo regulates the tumour immune microenvironment. Engineered exosomes are involved in the immune regulation of breast cancer.


Subject(s)
Breast Neoplasms , Exosomes , Humans , Female , Breast Neoplasms/genetics , Breast Neoplasms/therapy , Exosomes/genetics , Immunotherapy , Tumor Microenvironment , Cell Communication
8.
Methods Mol Biol ; 2797: 211-225, 2024.
Article in English | MEDLINE | ID: mdl-38570462

ABSTRACT

Missense mutations in the RAS family of oncogenes (HRAS, KRAS, and NRAS) are present in approximately 20% of human cancers, making RAS a valuable therapeutic target (Prior et al., Cancer Res 80:2969-2974, 2020). Although decades of research efforts to develop therapeutic inhibitors of RAS were unsuccessful, there has been success in recent years with the entrance of FDA-approved KRASG12C-specific inhibitors to the clinic (Skoulidis et al., N Engl J Med 384:2371-2381, 2021; Jänne et al., N Engl J Med 387:120-131, 2022). Additionally, KRASG12D-specific inhibitors are presently undergoing clinical trials (Wang et al., J Med Chem 65:3123-3133, 2022). The advent of these allele specific inhibitors has disproved the previous notion that RAS is undruggable. Despite these advancements in RAS-targeted therapeutics, several RAS mutants that frequently arise in cancers remain without tractable drugs. Thus, it is critical to further understand the function and biology of RAS in cells and to develop tools to identify novel therapeutic vulnerabilities for development of anti-RAS therapeutics. To do this, we have exploited the use of monobody (Mb) technology to develop specific protein-based inhibitors of selected RAS isoforms and mutants (Spencer-Smith et al., Nat Chem Biol 13:62-68, 2017; Khan et al., Cell Rep 38:110322, 2022; Wallon et al., Proc Natl Acad Sci USA 119:e2204481119, 2022; Khan et al., Small GTPases 13:114-127, 2021; Khan et al., Oncogene 38:2984-2993, 2019). Herein, we describe our combined use of Mbs and NanoLuc Binary Technology (NanoBiT) to analyze RAS protein-protein interactions and to screen for RAS-binding small molecules in live-cell, high-throughput assays.


Subject(s)
Luciferases , Neoplasms , Proto-Oncogene Proteins p21(ras) , Humans , Neoplasms/drug therapy , Neoplasms/genetics , Oncogenes , Cell Communication , Mutation
9.
Int J Nanomedicine ; 19: 3109-3121, 2024.
Article in English | MEDLINE | ID: mdl-38567379

ABSTRACT

Purpose: Exosomes are important "messengers" in cell-cell interactions, but their potential effects on palatal fusion are still unknown. This study aimed to explore the role and mechanism of exosomes derived from palatal mesenchymal cells in epithelial-mesenchymal communication during palatogenesis. Methods: The expression of exosome marker CD63 and CD81 in palatal cells during palatogenesis was detected by immunofluorescence staining. After being purified from the supernatant of human embryonic palatal mesenchymal (HEPM) cells, exosomes (HEPM-EXO) were characterized by nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM) and Western blot. HEPM-EXO were co-cultured with human immortalized oral epithelial cells (HIOEC). The effects of HEPM-EXO on the cell proliferation, migration, apoptosis and epithelial-mesenchymal transition (EMT) of HIOEC were evaluated. The proteins encapsulated in HEPM-EXO were analyzed by proteomic analysis. Results: The extensive expression of CD63 and CD81 in palatal epithelial and mesenchymal cells were continuously detected during E12.5~E14.5, suggesting that exosomes were involved in the process of palatal fusion. The expression of CD63 was also observed in the acellular basement membrane between the palatal epithelium and the mesenchyme in vivo, and HEPM-EXO could be internalized by HIOEC in vitro, suggesting that exosomes are potent to diffuse through the cellular tissue boundary to mediate palatal cell-cell communication. Exposure of HEPM-EXO to HIOEC substantially inhibited the proliferation and stimulated the migration of HIOEC, but had no significant effect on cell apoptosis and EMT. Proteomic analysis revealed the basic characteristics of the proteins in HEPM-EXO and that exosomal THBS1 may potentially regulate the cell behaviors of HIOEC, which needs further verification. Gene ontology (GO) analysis uncovered that the proteins highly expressed in HEPM-EXO are closely related to wound healing, implying a promising therapeutic opportunity of HEPM-EXO in tissue injury treatment with future studies. Conclusion: HEPM-EXO mediated cell-cell communication by regulating cell proliferation and migration of oral epithelial cells during palatogenesis.


Subject(s)
Exosomes , Humans , Exosomes/metabolism , Proteomics , Cell Communication , Epithelial Cells , Wound Healing
10.
PeerJ ; 12: e17146, 2024.
Article in English | MEDLINE | ID: mdl-38560468

ABSTRACT

Exosomes are vesicles with a lipid bilayer structure that carry various active substances, such as proteins, DNA, non-coding RNA, and nucleic acids; these participate in the immune response, tissue formation, and cell communication. Owing to their low immunogenicity, exosomes play a key role in regulating the skeletal immune environment. Macrophages are important immune cells that swallow various cellular and tissue fragments. M1-like and M2-like macrophages differentiate to play pro-inflammatory, anti-inflammatory, and repair roles following stimulation. In recent years, the increase in the population base and the aging of the population have led to a gradual rise in orthopedic diseases, placing a heavy burden on the social medical system and making it urgent to find effective solutions. Macrophages and their exosomes have been demonstrated to be closely associated with the pathogenesis and prognosis of orthopedic diseases. An in-depth understanding of their mechanisms of action and the interaction between them will be helpful for the future clinical treatment of orthopedic diseases. This review focuses on the mechanisms of action, diagnosis, and treatment of orthopedic diseases involving macrophages and their exosomes, including fracture healing, diabetic bone damage, osteosarcoma, and rheumatoid arthritis. In addition, we discuss the prospects and major challenges faced by macrophages and their exosomes in clinical practice.


Subject(s)
Arthritis, Rheumatoid , Exosomes , Humans , Macrophages , Arthritis, Rheumatoid/metabolism , Cell Communication
11.
J Clin Invest ; 134(7)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38557494

ABSTRACT

Metabolic dysfunction-associated steatotic liver disease (MASLD) affects nearly 40% of the global adult population and may progress to metabolic dysfunction-associated steatohepatitis (MASH), and MASH-associated liver fibrosis and cirrhosis. Despite numerous studies unraveling the mechanism of hepatic fibrogenesis, there are still no approved antifibrotic therapies. The development of MASLD and liver fibrosis results from complex cell-cell interactions that often initiate within hepatocytes but remain incompletely understood. In this issue of the JCI, Yan and colleagues describe an ATF3/HES1/CEBPA/OPN pathway that links hepatocyte signals to fibrogenic activation of hepatic stellate cells and may provide new perspectives on therapeutic options for MASLD-induced liver fibrosis.


Subject(s)
Fatty Liver , Liver Cirrhosis , Adult , Humans , Hepatocytes , Hepatic Stellate Cells , Cell Communication
12.
Cell Mol Life Sci ; 81(1): 171, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38597989

ABSTRACT

Intercellular communication via gap junctions has a fundamental role in regulating cell growth and tissue homeostasis, and its dysregulation may be involved in cancer development and radio- and chemotherapy resistance. Connexin43 (Cx43) is the most ubiquitously expressed gap junction channel protein in human tissues. Emerging evidence indicates that dysregulation of the sorting of Cx43 to lysosomes is important in mediating the loss of Cx43-based gap junctions in cancer cells. However, the molecular basis underlying this process is currently poorly understood. Here, we identified the E3 ubiquitin ligase ITCH as a novel regulator of intercellular communication via gap junctions. We demonstrate that ITCH promotes loss of gap junctions in cervical cancer cells, which is associated with increased degradation of Cx43 in lysosomes. The data further indicate that ITCH interacts with and regulates Cx43 ubiquitination and that the ITCH-induced loss of Cx43-based gap junctions requires its catalytic HECT (homologous to E6-AP C-terminus) domain. The data also suggest that the ability of ITCH to efficiently promote loss of Cx43-based gap junctions and degradation of Cx43 depends on a functional PY (PPXY) motif in the C-terminal tail of Cx43. Together, these data provide new insights into the molecular basis underlying the degradation of Cx43 and have implications for the understanding of how intercellular communication via gap junctions is lost during cancer development.


Subject(s)
Connexin 43 , Ubiquitin-Protein Ligases , Humans , Connexin 43/genetics , Ubiquitin-Protein Ligases/genetics , Gap Junctions , Lysosomes , Connexins , Cell Communication
13.
J Cancer Res Clin Oncol ; 150(4): 184, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38598014

ABSTRACT

BACKGROUND: Extracellular vesicles (EVs) can mediate cell-to-cell communication and affect various physiological and pathological processes in both parent and recipient cells. Currently, extensive research has focused on the EVs derived from cell cultures and various body fluids. However, insufficient attention has been paid to the EVs derived from tissues. Tissue EVs can reflect the microenvironment of the specific tissue and the cross-talk of communication among different cells, which can provide more accurate and comprehensive information for understanding the development and progression of diseases. METHODS: We review the state-of-the-art technologies involved in the isolation and purification of tissue EVs. Then, the latest research progress of tissue EVs in the mechanism of tumor occurrence and development is presented. And finally, the application of tissue EVs in the clinical diagnosis and treatment of cancer is anticipated. RESULTS: We evaluate the strengths and weaknesses of various tissue processing and EVs isolation methods, and subsequently analyze the significance of protein characterization in determining the purity of tissue EVs. Furthermore, we focus on outlining the importance of EVs derived from tumor and adipose tissues in tumorigenesis and development, as well as their potential applications in early tumor diagnosis, prognosis, and treatment. CONCLUSION: When isolating and characterizing tissue EVs, the most appropriate protocol needs to be specified based on the characteristics of different tissues. Tissue EVs are valuable in the diagnosis, prognosis, and treatment of tumors, and the potential risks associated with tissue EVs need to be considered as therapeutic agents.


Subject(s)
Body Fluids , Extracellular Vesicles , Neoplasms , Humans , Carcinogenesis , Cell Communication , Tumor Microenvironment
14.
Radiat Res ; 201(4): 294-303, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38588381

ABSTRACT

Radiation-induced intestinal damage (RIID) is a common side effect of radiotherapy in patients with abdominopelvic malignancies. Gap junctions are special structures consisting of connexins (Cxs). This study aimed to investigate the expression and role of connexins in RIID and underlying mechanism. In this study, a calcein-AM fluorescence probe was used to detect changes in gap junctional intercellular communication in intestinal epithelial IEC-6 cells. Our results show that gap junctional intercellular communication of IEC-6 cells was reduced at 6, 12, 24, and 48 h after irradiation, with the most pronounced effect at 24 h. Western blotting and immunofluorescence results showed that the expression of Cx43, but not other connexins, was reduced in irradiated intestinal epithelial cells. Silencing of Cx43 reduced gap junctional intercellular communication between irradiated intestinal epithelial cells with increased ROS and intracellular Ca2+ levels. Furthermore, knockdown of Cx43 reduced the number of clonal clusters, decreased cell proliferation with increased cytotoxicity and apoptosis. Western blotting results showed that silencing of Cx43 resulted in changed γ-H2AX and PI3K/AKT pathway proteins in irradiated intestinal epithelial cells. Administration of the PI3K/AKT pathway inhibitor LY294002 inhibited the radioprotective effects in Cx43-overexpressing intestinal epithelial cells. Our study demonstrated that Cx43 expression is decreased by ionizing radiation, which facilitates the radioprotection of intestinal epithelial cells.


Subject(s)
Connexin 43 , Proto-Oncogene Proteins c-akt , Humans , Proto-Oncogene Proteins c-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Calcium/metabolism , Connexins/metabolism , Connexins/pharmacology , Signal Transduction , Gap Junctions , Cell Communication
15.
Food Chem Toxicol ; 187: 114629, 2024 May.
Article in English | MEDLINE | ID: mdl-38565334

ABSTRACT

Chlorpyrifos (CPF), a widely used organophosphorus pesticide (OP) to control pests has been verified reproductive toxicity on mammalian oocytes. However, limited information exists on its correlation with the dysfunction of the intercellular communication in cumulus-oocyte complexes (COCs). Herein, our study utilized porcine COCs as models to directly address the latent impact of CPF on the communication between cumulus cells (CCs) and oocytes during in vitro maturation. The results demonstrated that CPF exposure decreased the rate of the first polar body (PB1) extrusion and blocked meiosis progression. Notably, the cumulus expansion of CPF-exposed COCs was suppressed significantly, accompanied by the down-regulated mRNA levels of cumulus expansion-related genes. Furthermore, the early apoptotic level was raised and the expression of BAX/BCL2 and cleaved caspase 3 was up-regulated in the CCs of CPF-exposed COCs (p < 0.05). Moreover, CPF exposure impaired mRNA levels of antioxidant enzyme-related genes, induced higher levels of reactive oxygen species (ROS) and reduced the levels of mitochondrial membrane potential (MMP) in CCs (p < 0.05). Additionally, the integrated optical density (IOD) rate (cumulus/oocyte) of calcein and the expression of connexin 43 (CX43) was increased in CPF treatment groups (p < 0.05). As well, CPF exposure reduced the expression levels of FSCN1, DAAM1 and MYO10, which resulted in a significant decrease in the number and fluorescence intensity of transzonal projections (TZPs). In conclusion, CPF inhibited the expansion of cumulus and caused oxidative stress and apoptosis as well as disturbed the function of gap junctions (GJs) and TZPs, which eventually resulted in the failure of oocyte maturation.


Subject(s)
Chlorpyrifos , Pesticides , Swine , Animals , Chlorpyrifos/toxicity , Chlorpyrifos/metabolism , Organophosphorus Compounds/metabolism , Pesticides/metabolism , Oocytes , Cell Communication , RNA, Messenger/genetics , RNA, Messenger/metabolism , Mammals
16.
Proc Natl Acad Sci U S A ; 121(16): e2309211121, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38593081

ABSTRACT

Vesicular release of neurotransmitters and hormones relies on the dynamic assembly of the exocytosis/trans-SNARE complex through sequential interactions of synaptobrevins, syntaxins, and SNAP-25. Despite SNARE-mediated release being fundamental for intercellular communication in all excitable tissues, the role of auxiliary proteins modulating the import of reserve vesicles to the active zone, and thus, scaling repetitive exocytosis remains less explored. Secretagogin is a Ca2+-sensor protein with SNAP-25 being its only known interacting partner. SNAP-25 anchors readily releasable vesicles within the active zone, thus being instrumental for 1st phase release. However, genetic deletion of secretagogin impedes 2nd phase release instead, calling for the existence of alternative protein-protein interactions. Here, we screened the secretagogin interactome in the brain and pancreas, and found syntaxin-4 grossly overrepresented. Ca2+-loaded secretagogin interacted with syntaxin-4 at nanomolar affinity and 1:1 stoichiometry. Crystal structures of the protein complexes revealed a hydrophobic groove in secretagogin for the binding of syntaxin-4. This groove was also used to bind SNAP-25. In mixtures of equimolar recombinant proteins, SNAP-25 was sequestered by secretagogin in competition with syntaxin-4. Kd differences suggested that secretagogin could shape unidirectional vesicle movement by sequential interactions, a hypothesis supported by in vitro biological data. This mechanism could facilitate the movement of transport vesicles toward release sites, particularly in the endocrine pancreas where secretagogin, SNAP-25, and syntaxin-4 coexist in both α- and ß-cells. Thus, secretagogin could modulate the pace and fidelity of vesicular hormone release by differential protein interactions.


Subject(s)
Membrane Fusion , Secretagogins , Qa-SNARE Proteins/genetics , Qa-SNARE Proteins/metabolism , Secretagogins/metabolism , Cell Membrane/metabolism , Synaptosomal-Associated Protein 25/metabolism , Exocytosis , Cell Communication , Syntaxin 1/metabolism , Protein Binding
17.
Proc Natl Acad Sci U S A ; 121(16): e2318155121, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38602917

ABSTRACT

Tissue development occurs through a complex interplay between many individual cells. Yet, the fundamental question of how collective tissue behavior emerges from heterogeneous and noisy information processing and transfer at the single-cell level remains unknown. Here, we reveal that tissue scale signaling regulation can arise from local gap-junction mediated cell-cell signaling through the spatiotemporal establishment of an intermediate-scale of transient multicellular communication communities over the course of tissue development. We demonstrated this intermediate scale of emergent signaling using Ca2+ signaling in the intact, ex vivo cultured, live developing Drosophila hematopoietic organ, the lymph gland. Recurrent activation of these transient signaling communities defined self-organized signaling "hotspots" that gradually formed over the course of larva development. These hotspots receive and transmit information to facilitate repetitive interactions with nonhotspot neighbors. Overall, this work bridges the scales between single-cell and emergent group behavior providing key mechanistic insight into how cells establish tissue-scale communication networks.


Subject(s)
Drosophila Proteins , Drosophila , Animals , Drosophila/metabolism , Hematopoiesis , Signal Transduction , Cell Communication , Drosophila Proteins/genetics , Drosophila Proteins/metabolism
18.
ACS Nano ; 18(15): 10464-10484, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38578701

ABSTRACT

Mammalian cells release a heterogeneous array of extracellular vesicles (EVs) that contribute to intercellular communication by means of the cargo that they carry. To resolve EV heterogeneity and determine if cargo is partitioned into select EV populations, we developed a method named "EV Fingerprinting" that discerns distinct vesicle populations using dimensional reduction of multiparametric data collected by quantitative single-EV flow cytometry. EV populations were found to be discernible by a combination of membrane order and EV size, both of which were obtained through multiparametric analysis of fluorescent features from the lipophilic dye Di-8-ANEPPS incorporated into the lipid bilayer. Molecular perturbation of EV secretion and biogenesis through respective ablation of the small GTPase Rab27a and overexpression of the EV-associated tetraspanin CD63 revealed distinct and selective alterations in EV populations, as well as cargo distribution. While Rab27a disproportionately affects all small EV populations with high membrane order, the overexpression of CD63 selectively increased the production of one small EV population of intermediate membrane order. Multiplexing experiments subsequently revealed that EV cargos have a distinct, nonrandom distribution with CD63 and CD81 selectively partitioning into smaller vs larger EVs, respectively. These studies not only present a method to probe EV biogenesis but also reveal how the selective partitioning of cargo contributes to EV heterogeneity.


Subject(s)
Extracellular Vesicles , Animals , Flow Cytometry , Lipid Bilayers , Cell Communication , Mammals
19.
Cell Death Dis ; 15(4): 271, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38632264

ABSTRACT

Diabetes, a group of metabolic disorders, constitutes an important global health problem. Diabetes and its complications place a heavy financial strain on both patients and the global healthcare establishment. The lack of effective treatments contributes to this pessimistic situation and negative outlook. Exosomes released from mesenchymal stromal cells (MSCs) have emerged as the most likely new breakthrough and advancement in treating of diabetes and diabetes-associated complication due to its capacity of intercellular communication, modulating the local microenvironment, and regulating cellular processes. In the present review, we briefly outlined the properties of MSCs-derived exosomes, provided a thorough summary of their biological functions and potential uses in diabetes and its related complications.


Subject(s)
Diabetes Complications , Diabetes Mellitus , Exosomes , Mesenchymal Stem Cells , Humans , Exosomes/metabolism , Diabetes Complications/metabolism , Cell Communication , Mesenchymal Stem Cells/metabolism , Treatment Outcome , Diabetes Mellitus/metabolism
20.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(2): 199-206, 2024 Apr 18.
Article in Chinese | MEDLINE | ID: mdl-38595234

ABSTRACT

OBJECTIVE: To delve deeply into the dynamic trajectories of cell subpopulations and the communication network among immune cell subgroups during the malignant progression of glioblastoma (GBM), and to endeavor to unearth key risk biomarkers in the GBM malignancy progression, so as to provide a more profound understanding for the treatment and prognosis of this disease by integrating transcriptomic data and clinical information of the GBM patients. METHODS: Utilizing single-cell sequencing data analysis, we constructed a cell subgroup atlas during the malignant progression of GBM. The Monocle2 tool was employed to build dynamic progression trajectories of the tumor cell subgroups in GBM. Through gene enrichment analysis, we explored the biological processes enriched in genes that significantly changed with the malignancy progression of GBM tumor cell subpopulations. CellChat was used to identify the communication network between the different immune cell subgroups. Survival analysis helped in identifying risk molecular markers that impacted the patient prognosis during the malignant progression of GBM. This method ological approach offered a comprehensive and detailed examination of the cellular and molecular dynamics within GBM, providing a robust framework for understanding the disease' s progression and potential therapeutic targets. RESULTS: The analysis of single-cell sequencing data identified 6 different cell types, including lymphocytes, pericytes, oligodendrocytes, macrophages, glioma cells, and microglia. The 27 151 cells in the single-cell dataset included 3 881 cells from the patients with low-grade glioma (LGG), 10 166 cells from the patients with newly diagnosed GBM, and 13 104 cells from the patients with recurrent glioma (rGBM). The pseudo-time analysis of the glioma cell subgroups indicated significant cellular heterogeneity during malignant progression. The cell interaction analysis of immune cell subgroups revealed the communication network among the different immune subgroups in GBM malignancy, identifying 22 biologically significant ligand-receptor pairs across 12 key biological pathways. Survival analysis had identified 8 genes related to the prognosis of the GBM patients, among which SERPINE1, COL6A1, SPP1, LTF, C1S, AEBP1, and SAA1L were high-risk genes in the GBM patients, and ABCC8 was low-risk genes in the GBM patients. These findings not only provided new theoretical bases for the treatment of GBM, but also offered fresh insights for the prognosis assessment and treatment decision-making for the GBM patients. CONCLUSION: This research comprehensively and profoundly reveals the dynamic changes in glioma cell subpopulations and the communication patterns among the immune cell subgroups during the malignant progression of GBM. These findings are of significant importance for understanding the complex biological processes of GBM, providing crucial new insights for precision medicine and treatment decisions in GBM. Through these studies, we hope to provide more effective treatment options and more accurate prognostic assessments for the patients with GBM.


Subject(s)
Brain Neoplasms , Glioblastoma , Glioma , Humans , Glioblastoma/genetics , Glioblastoma/metabolism , Glioblastoma/pathology , Brain Neoplasms/genetics , Neoplasm Recurrence, Local , Prognosis , Cell Communication , Carboxypeptidases , Repressor Proteins
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