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Found: 5 473
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Personalized Vascularized Tumor Organoid-on-a-Chip for Tumor Metastasis and Therapeutic Targeting Assessment.
While tumor organoids have revolutionized cancer research by recapitulating the cellular architecture and behaviors of real tumors in vitro, their lack of functional vasculature hinders their attainment of full physiological capabilities. Current efforts to vascularize organoids are struggling to achieve well-defined vascular networks, mimicking the intricate hierarchy observed in vivo, which restricts the physiological relevance particularly for studying tumor progression and response to therapies targeting the tumor vasculature. An innovative vascularized patient-derived tumor organoids (PDTOs)-on-a-chip with hierarchical, tumor-specific microvasculature is presented, providing a versatile platform to explore tumor-vascular dynamics and antivascular drug efficacy. It is found that highly metastatic tumor cells induced vessel angiogenesis and simultaneously migrated toward blood vessels via the Notch pathway. The evident association between the angiogenic and migratory capacities of PDTOs and their clinical metastatic outcomes underscores the potential of the innovative platform for evaluating tumor metastasis, thus offering valuable insights for clinical decision-making. Ultimately, the system represents a promising avenue for advancing the understanding of tumor metastasis and developing personalized treatment strategies based on patient-specific tumor characteristics.
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Nutrient sensing by absorptive and secretory progenies of small intestinal stem cells.
Nutrient sensing triggers responses by the gut-brain axis modulating hormone release, feeding behavior and metabolism that become dysregulated in metabolic syndrome and some cancers. Except for absorptive enterocytes and secretory enteroendocrine cells, the ability of many intestinal cell types to sense nutrients is still unknown; hence we hypothesized that progenitor stem cells (intestinal stem cells, ISC) possess nutrient sensing ability inherited by progenies during differentiation. We directed via modulators of Wnt and Notch signaling differentiation of precursor mouse intestinal crypts into specialized organoids each containing ISC, enterocyte, goblet, or Paneth cells at relative proportions much higher than in situ as determined by mRNA expression and immunocytochemistry of cell type biomarkers. We identified nutrient sensing cell type(s) by increased expression of fructolytic genes in response to a fructose challenge. Organoids comprised primarily of enterocytes, Paneth, or goblet, but not ISC, cells responded specifically to fructose without affecting nonfructolytic genes. Sensing was independent of Wnt and Notch modulators and of glucose concentrations in the medium but required fructose absorption and metabolism. More mature enterocyte- and goblet-enriched organoids exhibited stronger fructose responses. Remarkably, enterocyte organoids, upon forced dedifferentiation to reacquire ISC characteristics, exhibited a markedly extended lifespan and retained fructose sensing ability, mimicking responses of some dedifferentiated cancer cells. Using an innovative approach, we discovered that nutrient sensing is likely repressed in progenitor ISCs then irreversibly derepressed during specification into sensing-competent absorptive or secretory lineages, the surprising capacity of Paneth and goblet cells to detect fructose, and the important role of differentiation in modulating nutrient sensing.NEW & NOTEWORTHY Small intestinal stem cells differentiate into several cell types transiently populating the villi. We used specialized organoid cultures each comprised of a single cell type to demonstrate that 1) differentiation seems required for nutrient sensing, 2) secretory goblet and Paneth cells along with enterocytes sense fructose, suggesting that sensing is acquired after differentiation is triggered but before divergence between absorptive and secretory lineages, and 3) forcibly dedifferentiated enterocytes exhibit fructose sensing and lifespan extension.
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Using human 3D organoid models to gain mechanistic insight in motor neuron diseases.
Motor neuron diseases (MNDs) are caused by the progressive loss of motor neurons and eventually lead to paralysis and death. Once viewed as primarily neurocentric, MNDs are now recognized to be driven by intertwined cell-autonomous and non-cell-autonomous mechanisms. Dissecting these interactions is essential for developing effective therapies. Here, we describe induced pluripotent stem cell-derived 3D models that can be used to capture distinct aspects of MND pathology. We show that spinal cord organoids can be used to investigate cell-autonomous mechanisms and motor neuron-glia interactions (with axially elongated spinal cord organoids being particularly useful to study developmental vulnerability) as well as in 3D muscle and combined neuromuscular models to dissect muscle pathology and neuromuscular junction dismantling. In parallel, we discuss advances in bioengineering, machine learning and human trunk-like models, which together can begin to reproduce the coordinated co-development and spatial organization of the multiple tissues affected in MNDs. We discuss how these systems have advanced our understanding of disease mechanisms and highlight opportunities for drug repurposing. Finally, we propose a mechanism-informed and phenotype-informed framework to guide 3D model selection for future research and to prioritize promising avenues for therapeutic development.
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Harnessing the Power of Stem Cell Models to Study Shared Genetic Variants in Congenital Heart Diseases and Neurodevelopmental Disorders.
Advances in human pluripotent stem cell (hPSC) technology allow one to deconstruct the human body into specific disease-relevant cell types or create functional units representing various organs. hPSC-based models present a unique opportunity for the study of co-occurring disorders where "cause and effect" can be addressed. Poor neurodevelopmental outcomes have been reported in children with congenital heart diseases (CHD). Intuitively, abnormal cardiac function or surgical intervention may stunt the developing brain, leading to neurodevelopmental disorders (NDD). However, recent work has uncovered several genetic variants within genes associated with the development of both the heart and brain that could also explain this co-occurrence. Given the scalability of hPSCs, straightforward genetic modification, and established differentiation strategies, it is now possible to investigate both CHD and NDD as independent events. We will first overview the potential for shared genetics in both heart and brain development. We will then summarize methods to differentiate both cardiac & neural cells and organoids from hPSCs that represent the developmental process of the heart and forebrain. Finally, we will highlight strategies to rapidly screen several genetic variants together to uncover potential phenotypes and how therapeutic advances could be achieved by hPSC-based models.
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One-Step Generation of Aqueous-Droplet-Filled Hydrogel Fibers as Organoid Carriers Using an All-in-Water Microfluidic System.
Hydrogel fibers are promising carriers for biological applications due to their flexible mechanical properties, well-defined spatial distribution, and excellent biocompatibility. In particular, the droplet-filled hydrogel fibers with the controllable dimension and location of droplets display great advantages to enhance the loading capacity of multiple components and biofunctions. In this work, we proposed a new all-in-water microfluidic system that allows for one-step fabrication of aqueous-droplet-filled hydrogel fibers (ADHFs) with unique morphology and tunable configurations. In the system, the aqueous droplets with equidistance are successfully arranged within the alginate calcium fibers, relying on the design of the pump valve cycle and the select of two immiscible liquids with a stable aqueous interface. The architecture of the ADHF can be flexibly controlled by adjusting the three phase flow rates and the valve switch cycle. The produced ADHFs exhibit high controllability, uniformity, biocompatibility, and stability. The established system enabled the formation of functional human islet organoids in situ through encapsulating pancreatic endocrine progenitor cells within microfibers. The generated islet organoids within droplets exhibit high cell viability and islet-specific function of insulin secretion. The proposed approach provides a new way to fabricate multifunctional hydrogel fibers for materials sciences, tissue engineering, and regenerative medicine.
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Patient-specific lung cancer tumoroids recapitulate the tumor microenvironments for functional evaluation of therapeutic responses and immune-stromal interactions.
BACKGROUND: Tumor heterogeneity and the complexity of the tumor microenvironment (TME) drive therapeutic resistance in lung cancer, highlighting the critical need for experimental models that faithfully recapitulate tumor-stroma-immune interactions. METHODS: We developed patient-specific lung cancer tumoroid (LCT) models by integrating lung cancer organoids (LCOs), cancer-associated fibroblasts (CAFs) and immune cells isolated from single tumor tissue sources using a modular, transwell-based culture platform. The model supports cryopreservation and reproducible reconstruction of cellular components. Multimodal assessments, including histological characterization, dose-response pharmacologic profiling, immune profiling, and transcriptomic analyses, were performed across diverse co-culture configurations to evaluate patient-specific TME features and treatment-associated responses. RESULTS: The LCT models successfully recapitulated key structural and cellular features of native TMEs, demonstrating high reproducibility across patient samples. Functional analyses revealed tumor-intrinsic heterogeneity in responses to chemotherapy and chemo-immunotherapy. CAF integration altered therapeutic responses and was associated with reduced immune activation and cytotoxic efficacy in selected models, suggesting stromal contributions to treatment resistance. Transcriptomic analyses showed that reconstructed TMEs preserved patient-specific stromal and immune programs associated with therapeutic responsiveness, including transcriptional features linked to clinical outcomes in independent immunotherapy-treated cohorts. CONCLUSIONS: This patient-specific LCT model provides a scalable and translationally relevant approach for the ex vivo reconstruction of native TMEs, facilitating the functional interrogation of tumor-stroma-immune interactions. By capturing heterogeneous stromal responses, this platform offers a valuable tool for investigating therapeutic resistance and supports the further development of precision immune-oncology and patient-tailored therapeutic strategies in lung cancer.
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Electrophysiological characterization of photoreceptor-like cells in human inducible pluripotent stem cell-derived retinal organoids during in vitro maturation.
Retinal organoids (ROs) derived from human inducible pluripotent stem cells (hiPSCs) exhibit considerable therapeutic potential. However, current quality control of ROs during in vitro differentiation is largely limited to the detection of molecular markers, often by immunostaining, polymerase chain reaction (PCR) assays and sequencing, often without proper functional assessments. As such, in the current study, we systemically characterized the physiological maturation of photoreceptor-like cells in hiPSC-derived ROs. By performing patch-clamp recordings from photoreceptor-like cells in ROs at distinct differentiation stages (ie, Differentiation Day [D]90, D150, and D200), we determined the electrophysiological properties of the plasma membrane and several characteristic ion channels closely associated with the physiological functions of the photoreceptors. Ionic hallmarks, such as hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and cyclic nucleotide-gated (CNG) channels, matured progressively during differentiation. After D200 in culture, these characteristic currents closely resembled those in macaque or human native photoreceptors. Furthermore, we demonstrated that the hyperpolarization-activated inward current/depolarization-activated outward current ratio (I-120 /I+40 ), termed as the inward-outward current (IOC) ratio hereon, accurately represented the maturity of photoreceptors and could serve as a sensitive indicator of pathological state. Thus, this study provides a comprehensive dataset describing the electrophysiological maturation of photoreceptor-like cells in hiPSC-derived ROs for precise and sensitive quality control during RO differentiation.
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Transcriptome-based molecular staging of human stem cell-derived retinal organoids uncovers accelerated photoreceptor differentiation by 9-cis retinal.
PURPOSE: Retinal organoids generated from human pluripotent stem cells exhibit considerable variability during differentiation. Our goals are to assess developmental maturity of the neural retina in vitro and design improved protocols based on objective criteria. METHODS: We performed transcriptome analyses of developing retinal organoids from human embryonic and induced pluripotent stem cell lines and utilized multiple bioinformatic tools for comparative analysis. Immunohistochemistry, immunoblotting and electron microscopy were employed for validation. RESULTS: We show that the developmental variability in organoids was reflected in gene expression profiles and could be evaluated by molecular staging with the human fetal and adult retinal transcriptome data. We also demonstrate that the addition of 9-cis retinal, instead of the widely used all-trans retinoic acid, accelerated rod photoreceptor differentiation in organoid cultures, with higher rhodopsin expression and more mature mitochondrial morphology evident by day 120. CONCLUSION: Our studies provide an objective transcriptome-based modality for determining the differentiation state of retinal organoids and for comparisons across different stem cell lines and platforms, which should facilitate disease modeling and evaluation of therapies in vitro.
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Pharmaco-proteogenomic characterization of liver cancer organoids for precision oncology.
Organoid models have the potential to recapitulate the biological and pharmacotypic features of parental tumors. Nevertheless, integrative pharmaco-proteogenomics analysis for drug response features and biomarker investigation for precision therapy of patients with liver cancer are still lacking. We established a patient-derived liver cancer organoid biobank (LICOB) that comprehensively represents the histological and molecular characteristics of various liver cancer types as determined by multiomics profiling, including genomic, epigenomic, transcriptomic, and proteomic analysis. Proteogenomic profiling of LICOB identified proliferative and metabolic organoid subtypes linked to patient prognosis. High-throughput drug screening revealed distinct response patterns of each subtype that were associated with specific multiomics signatures. Through integrative analyses of LICOB pharmaco-proteogenomics data, we identified the molecular features associated with drug responses and predicted potential drug combinations for personalized patient treatment. The synergistic inhibition effect of mTOR inhibitor temsirolimus and the multitargeted tyrosine kinase inhibitor lenvatinib was validated in organoids and patient-derived xenografts models. We also provide a user-friendly web portal to help serve the biomedical research community. Our study is a rich resource for investigation of liver cancer biology and pharmacological dependencies and may help enable functional precision medicine.
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The multifaceted role of LRRK2 in Parkinson's disease: From human iPSC to organoids.
Parkinson's disease (PD) is the second most common neurodegenerative disease affecting elderly people. Pathogenic mutations in Leucine-Rich Repeat Kinase 2 (LRRK2) are the most common cause of autosomal dominant PD. LRRK2 activity is enhanced in both familial and idiopathic PD, thereby studies on LRRK2-related PD research are essential for understanding PD pathology. Finding an appropriate model to mimic PD pathology is crucial for revealing the molecular mechanisms underlying disease progression, and aiding drug discovery. In the last few years, the use of human-induced pluripotent stem cells (hiPSCs) grew exponentially, especially in studying neurodegenerative diseases like PD, where working with brain neurons and glial cells was mainly possible using postmortem samples. In this review, we will discuss the use of hiPSCs as a model for PD pathology and research on the LRRK2 function in both neuronal and immune cells, together with reviewing the recent advances in 3D organoid models and microfluidics.