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2.
Curr Biol ; 34(12): 2623-2632.e5, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38823383

RESUMO

The sense of taste is essential for survival, as it allows animals to distinguish between foods that are nutritious from those that are toxic. However, innate responses to different tastants can be modulated or even reversed under pathological conditions. Here, we examined whether and how the internal status of an animal impacts taste valence by using Drosophila models of hyperproliferation in the gut. In all three models where we expressed proliferation-inducing transgenes in intestinal stem cells (ISCs), hyperproliferation of ISCs caused a tumor-like phenotype in the gut. While tumor-bearing flies had no deficiency in overall food intake, strikingly, they exhibited an increased gustatory preference for aristolochic acid (ARI), which is a bitter and normally aversive plant-derived chemical. ARI had anti-tumor effects in all three of our gut hyperproliferation models. For other aversive chemicals we tested that are bitter but do not have anti-tumor effects, gut tumors did not affect avoidance behaviors. We demonstrated that bitter-sensing gustatory receptor neurons (GRNs) in tumor-bearing flies respond normally to ARI. Therefore, the internal pathology of gut hyperproliferation affects neural circuits that determine taste valence postsynaptic to GRNs rather than altering taste identity by GRNs. Overall, our data suggest that increased consumption of ARI may represent an attempt at self-medication. Finally, although ARI's potential use as a chemotherapeutic agent is limited by its known toxicity in the liver and kidney, our findings suggest that tumor-bearing flies might be a useful animal model to screen for novel anti-tumor drugs.


Assuntos
Drosophila melanogaster , Paladar , Animais , Paladar/fisiologia , Drosophila melanogaster/fisiologia , Drosophila melanogaster/efeitos dos fármacos , Ácidos Aristolóquicos , Neoplasias Intestinais/tratamento farmacológico , Neoplasias Intestinais/patologia
3.
Cell Mol Gastroenterol Hepatol ; 18(2): 101349, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38697357

RESUMO

BACKGROUND & AIMS: Humans with WNT2B deficiency have severe intestinal disease, including significant inflammatory injury, highlighting a critical role for WNT2B. We sought to understand how WNT2B contributes to intestinal homeostasis. METHODS: We investigated the intestinal health of Wnt2b knock out (KO) mice. We assessed the baseline histology and health of the small intestine and colon, and the impact of inflammatory challenge using dextran sodium sulfate (DSS). We also evaluated human intestinal tissue. RESULTS: Mice with WNT2B deficiency had normal baseline histology but enhanced susceptibility to DSS colitis because of an increased early injury response. Although intestinal stem cells markers were decreased, epithelial proliferation was similar to control subjects. Wnt2b KO mice showed an enhanced inflammatory signature after DSS treatment. Wnt2b KO colon and human WNT2B-deficient organoids had increased levels of CXCR4 and IL6, and biopsy tissue from humans showed increased neutrophils. CONCLUSIONS: WNT2B is important for regulation of inflammation in the intestine. Absence of WNT2B leads to increased expression of inflammatory cytokines and increased susceptibility to gastrointestinal inflammation, particularly in the colon.


Assuntos
Colite , Citocinas , Sulfato de Dextrana , Proteínas Wnt , Animais , Humanos , Camundongos , Colite/patologia , Colite/induzido quimicamente , Colite/metabolismo , Colo/patologia , Colo/metabolismo , Citocinas/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Suscetibilidade a Doenças , Glicoproteínas , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/imunologia , Camundongos Knockout , Organoides/metabolismo , Organoides/patologia , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Proteínas Wnt/metabolismo
4.
Gastroenterology ; 166(3): 437-449, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37995867

RESUMO

BACKGROUND & AIMS: RET tyrosine kinase is necessary for enteric nervous system development. Loss-of-function RET mutations cause Hirschsprung disease (HSCR), in which infants are born with aganglionic bowel. Despite surgical correction, patients with HSCR often experience chronic defecatory dysfunction and enterocolitis, suggesting that RET is important after development. To test this hypothesis, we determined the location of postnatal RET and its significance in gastrointestinal (GI) motility. METHODS: RetCFP/+ mice and human transcriptional profiling data were studied to identify the enteric neuronal and epithelial cells that express RET. To determine whether RET regulates gut motility in vivo, genetic, and pharmacologic approaches were used to disrupt RET in all RET-expressing cells, a subset of enteric neurons, or intestinal epithelial cells. RESULTS: Distinct subsets of enteric neurons and enteroendocrine cells expressed RET in the adult intestine. RET disruption in the epithelium, rather than in enteric neurons, slowed GI motility selectively in male mice. RET kinase inhibition phenocopied this effect. Most RET+ epithelial cells were either enterochromaffin cells that release serotonin or L-cells that release peptide YY (PYY) and glucagon-like peptide 1 (GLP-1), both of which can alter motility. RET kinase inhibition exaggerated PYY and GLP-1 release in a nutrient-dependent manner without altering serotonin secretion in mice and human organoids. PYY receptor blockade rescued dysmotility in mice lacking epithelial RET. CONCLUSIONS: RET signaling normally limits nutrient-dependent peptide release from L-cells and this activity is necessary for normal intestinal motility in male mice. These effects could contribute to dysmotility in HSCR, which predominantly affects males, and uncovers a mechanism that could be targeted to treat post-prandial GI dysfunction.


Assuntos
Sistema Nervoso Entérico , Doença de Hirschsprung , Lactente , Humanos , Masculino , Camundongos , Animais , Peptídeo YY , Serotonina , Doença de Hirschsprung/genética , Células Enteroendócrinas , Intestino Delgado , Peptídeo 1 Semelhante ao Glucagon , Proteínas Proto-Oncogênicas c-ret/genética
5.
Dev Cell ; 59(2): 244-261.e6, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38154460

RESUMO

WNT morphogens trigger signaling pathways fundamental for embryogenesis, regeneration, and cancer. WNTs are modified with palmitoleate, which is critical for binding Frizzled (FZD) receptors and activating signaling. However, it is unknown how WNTs are released and spread from cells, given their strong lipid-dependent membrane attachment. We demonstrate that secreted FZD-related proteins and WNT inhibitory factor 1 are WNT carriers, potently releasing lipidated WNTs and forming active soluble complexes. WNT release occurs by direct handoff from the membrane protein WNTLESS to the carriers. In turn, carriers donate WNTs to glypicans and FZDs involved in WNT reception and to the NOTUM hydrolase, which antagonizes WNTs by lipid moiety removal. WNT transfer from carriers to FZDs is greatly facilitated by glypicans that serve as essential co-receptors in Wnt signaling. Thus, an extracellular network of carriers dynamically controls secretion, posttranslational regulation, and delivery of WNT morphogens, with important practical implications for regenerative medicine.


Assuntos
Glipicanas , Proteínas Wnt , Proteínas Wnt/metabolismo , Glipicanas/metabolismo , Via de Sinalização Wnt , Desenvolvimento Embrionário , Lipídeos , Receptores Frizzled/química , Receptores Frizzled/metabolismo
6.
JCI Insight ; 8(14)2023 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-37310791

RESUMO

The mineralocorticoid aldosterone, secreted by the adrenal zona glomerulosa (ZG), is critical for life, maintaining ion homeostasis and blood pressure. Therapeutic inhibition of protein phosphatase 3 (calcineurin, Cn) results in inappropriately low plasma aldosterone levels despite concomitant hyperkalemia and hyperreninemia. We tested the hypothesis that Cn participates in the signal transduction pathway regulating aldosterone synthesis. Inhibition of Cn with tacrolimus abolished the potassium-stimulated (K+-stimulated) expression of aldosterone synthase, encoded by CYP11B2, in the NCI-H295R human adrenocortical cell line as well as ex vivo in mouse and human adrenal tissue. ZG-specific deletion of the regulatory Cn subunit CnB1 diminished Cyp11b2 expression in vivo and disrupted K+-mediated aldosterone synthesis. Phosphoproteomics analysis identified nuclear factor of activated T cells, cytoplasmic 4 (NFATC4), as a target for Cn-mediated dephosphorylation. Deletion of NFATC4 impaired K+-dependent stimulation of CYP11B2 expression and aldosterone production while expression of a constitutively active form of NFATC4 increased expression of CYP11B2 in NCI-H295R cells. Chromatin immunoprecipitation revealed NFATC4 directly regulated CYP11B2 expression. Thus, Cn controls aldosterone production via the Cn/NFATC4 pathway. Inhibition of Cn/NFATC4 signaling may explain low plasma aldosterone levels and hyperkalemia in patients treated with tacrolimus, and the Cn/NFATC4 pathway may provide novel molecular targets to treat primary aldosteronism.


Assuntos
Aldosterona , Calcineurina , Hiperpotassemia , Fatores de Transcrição NFATC , Animais , Humanos , Camundongos , Aldosterona/metabolismo , Calcineurina/metabolismo , Citocromo P-450 CYP11B2/genética , Fatores de Transcrição NFATC/genética , Tacrolimo/farmacologia
7.
Cancer Res ; 83(13): 2123-2141, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37129912

RESUMO

Adrenocortical carcinoma (ACC) is a rare cancer in which tissue-specific differentiation is paradoxically associated with dismal outcomes. The differentiated ACC subtype CIMP-high is prevalent, incurable, and routinely fatal. CIMP-high ACC possess abnormal DNA methylation and frequent ß-catenin-activating mutations. Here, we demonstrated that ACC differentiation is maintained by a balance between nuclear, tissue-specific ß-catenin-containing complexes, and the epigenome. On chromatin, ß-catenin bound master adrenal transcription factor SF1 and hijacked the adrenocortical super-enhancer landscape to maintain differentiation in CIMP-high ACC; off chromatin, ß-catenin bound histone methyltransferase EZH2. SF1/ß-catenin and EZH2/ß-catenin complexes present in normal adrenals persisted through all phases of ACC evolution. Pharmacologic EZH2 inhibition in CIMP-high ACC expelled SF1/ß-catenin from chromatin and favored EZH2/ß-catenin assembly, erasing differentiation and restraining cancer growth in vitro and in vivo. These studies illustrate how tissue-specific programs shape oncogene selection, surreptitiously encoding targetable therapeutic vulnerabilities. SIGNIFICANCE: Oncogenic ß-catenin can use tissue-specific partners to regulate cellular differentiation programs that can be reversed by epigenetic therapies, identifying epigenetic control of differentiation as a viable target for ß-catenin-driven cancers.


Assuntos
Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/metabolismo , Carcinoma Adrenocortical/patologia , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/patologia , Epigênese Genética , Cromatina/genética
8.
Nat Cell Biol ; 25(5): 778-786, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37106062

RESUMO

Gut stem cells are accessible by biopsy and propagate robustly in culture, offering an invaluable resource for autologous cell therapies. Insulin-producing cells can be induced in mouse gut, but it has not been possible to generate abundant and durable insulin-secreting cells from human gut tissues to evaluate their potential as a cell therapy for diabetes. Here we describe a protocol to differentiate cultured human gastric stem cells into pancreatic islet-like organoids containing gastric insulin-secreting (GINS) cells that resemble ß-cells in molecular hallmarks and function. Sequential activation of the inducing factors NGN3 and PDX1-MAFA led human gastric stem cells onto a distinctive differentiation path, including a SOX4High endocrine and GalaninHigh GINS precursor, before adopting ß-cell identity, at efficiencies close to 70%. GINS organoids acquired glucose-stimulated insulin secretion in 10 days and restored glucose homeostasis for over 100 days in diabetic mice after transplantation, providing proof of concept for a promising approach to treat diabetes.


Assuntos
Diabetes Mellitus Experimental , Células Secretoras de Insulina , Humanos , Diferenciação Celular/fisiologia , Diabetes Mellitus Experimental/terapia , Glucose , Homeostase , Insulina , Organoides , Fatores de Transcrição SOXC , Estômago
9.
Gut ; 72(5): 870-881, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35537812

RESUMO

OBJECTIVE: Intestinal barrier loss is a Crohn's disease (CD) risk factor. This may be related to increased expression and enzymatic activation of myosin light chain kinase 1 (MLCK1), which increases intestinal paracellular permeability and correlates with CD severity. Moreover, preclinical studies have shown that MLCK1 recruitment to cell junctions is required for tumour necrosis factor (TNF)-induced barrier loss as well as experimental inflammatory bowel disease progression. We sought to define mechanisms of MLCK1 recruitment and to target this process pharmacologically. DESIGN: Protein interactions between FK506 binding protein 8 (FKBP8) and MLCK1 were assessed in vitro. Transgenic and knockout intestinal epithelial cell lines, human intestinal organoids, and mice were used as preclinical models. Discoveries were validated in biopsies from patients with CD and control subjects. RESULTS: MLCK1 interacted specifically with the tacrolimus-binding FKBP8 PPI domain. Knockout or dominant negative FKBP8 expression prevented TNF-induced MLCK1 recruitment and barrier loss in vitro. MLCK1-FKBP8 binding was blocked by tacrolimus, which reversed TNF-induced MLCK1-FKBP8 interactions, MLCK1 recruitment and barrier loss in vitro and in vivo. Biopsies of patient with CD demonstrated increased numbers of MLCK1-FKBP8 interactions at intercellular junctions relative to control subjects. CONCLUSION: Binding to FKBP8, which can be blocked by tacrolimus, is required for MLCK1 recruitment to intercellular junctions and downstream events leading to immune-mediated barrier loss. The observed increases in MLCK1 activity, MLCK1 localisation at cell junctions and perijunctional MLCK1-FKBP8 interactions in CD suggest that targeting this process may be therapeutic in human disease. These new insights into mechanisms of disease-associated barrier loss provide a critical foundation for therapeutic exploitation of FKBP8-MLCK1 interactions.


Assuntos
Doença de Crohn , Animais , Humanos , Camundongos , Células CACO-2 , Doença de Crohn/tratamento farmacológico , Doença de Crohn/metabolismo , Mucosa Intestinal/metabolismo , Camundongos Knockout , Quinase de Cadeia Leve de Miosina/metabolismo , Tacrolimo/farmacologia , Proteínas de Ligação a Tacrolimo/metabolismo , Junções Íntimas/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
10.
Nat Commun ; 13(1): 7858, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36543805

RESUMO

SUMOylation is a dynamic posttranslational modification, that provides fine-tuning of protein function involved in the cellular response to stress, differentiation, and tissue development. In the adrenal cortex, an emblematic endocrine organ that mediates adaptation to physiological demands, the SUMOylation gradient is inversely correlated with the gradient of cellular differentiation raising important questions about its role in functional zonation and the response to stress. Considering that SUMO-specific protease 2 (SENP2), a deSUMOylating enzyme, is upregulated by Adrenocorticotropic Hormone (ACTH)/cAMP-dependent Protein Kinase (PKA) signalling within the zona fasciculata, we generated mice with adrenal-specific Senp2 loss to address these questions. Disruption of SENP2 activity in steroidogenic cells leads to specific hypoplasia of the zona fasciculata, a blunted reponse to ACTH and isolated glucocorticoid deficiency. Mechanistically, overSUMOylation resulting from SENP2 loss shifts the balance between ACTH/PKA and WNT/ß-catenin signalling leading to repression of PKA activity and ectopic activation of ß-catenin. At the cellular level, this blocks transdifferentiation of ß-catenin-positive zona glomerulosa cells into fasciculata cells and sensitises them to premature apoptosis. Our findings indicate that the SUMO pathway is critical for adrenal homeostasis and stress responsiveness.


Assuntos
Transdiferenciação Celular , Cisteína Endopeptidases , Glucocorticoides , Animais , Camundongos , Córtex Suprarrenal/metabolismo , Corticosteroides/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , beta Catenina/metabolismo , Transdiferenciação Celular/genética , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Glucocorticoides/metabolismo , Via de Sinalização Wnt
11.
Cell Rep ; 40(2): 111073, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35830806

RESUMO

Mutations in the catalytic subunit of protein kinase A (PKAc) drive the stress hormone disorder adrenal Cushing's syndrome. We define mechanisms of action for the PKAc-L205R and W196R variants. Proximity proteomic techniques demonstrate that both Cushing's mutants are excluded from A kinase-anchoring protein (AKAP)-signaling islands, whereas live-cell photoactivation microscopy reveals that these kinase mutants indiscriminately diffuse throughout the cell. Only cAMP analog drugs that displace native PKAc from AKAPs enhance cortisol release. Rescue experiments that incorporate PKAc mutants into AKAP complexes abolish cortisol overproduction, indicating that kinase anchoring restores normal endocrine function. Analyses of adrenal-specific PKAc-W196R knockin mice and Cushing's syndrome patient tissue reveal defective signaling mechanisms of the disease. Surprisingly each Cushing's mutant engages a different mitogenic-signaling pathway, with upregulation of YAP/TAZ by PKAc-L205R and ERK kinase activation by PKAc-W196R. Thus, aberrant spatiotemporal regulation of each Cushing's variant promotes the transmission of distinct downstream pathogenic signals.


Assuntos
Síndrome de Cushing , Animais , Domínio Catalítico/genética , Síndrome de Cushing/genética , Síndrome de Cushing/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Hidrocortisona/metabolismo , Camundongos , Proteômica
12.
Nat Commun ; 13(1): 1503, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35314684

RESUMO

Although reprogramming of cellular metabolism is a hallmark of cancer, little is known about how metabolic reprogramming contributes to early stages of transformation. Here, we show that the histone deacetylase SIRT6 regulates tumor initiation during intestinal cancer by controlling glucose metabolism. Loss of SIRT6 results in an increase in the number of intestinal stem cells (ISCs), which translates into enhanced tumor initiating potential in APCmin mice. By tracking down the connection between glucose metabolism and tumor initiation, we find a metabolic compartmentalization within the intestinal epithelium and adenomas, where a rare population of cells exhibit features of Warburg-like metabolism characterized by high pyruvate dehydrogenase kinase (PDK) activity. Our results show that these cells are quiescent cells expressing +4 ISCs and enteroendocrine markers. Active glycolysis in these cells suppresses ROS accumulation and enhances their stem cell and tumorigenic potential. Our studies reveal that aerobic glycolysis represents a heterogeneous feature of cancer, and indicate that this metabolic adaptation can occur in non-dividing cells, suggesting a role for the Warburg effect beyond biomass production in tumors.


Assuntos
Neoplasias , Sirtuínas , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Glicólise/fisiologia , Intestinos/patologia , Camundongos , Neoplasias/patologia , Piruvato Desidrogenase Quinase de Transferência de Acetil , Sirtuínas/metabolismo
13.
Nat Protoc ; 16(8): 3874-3900, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34183870

RESUMO

The presence of microbes in the colon impacts host physiology. Therefore, microbes are being evaluated as potential treatments for colorectal diseases. Humanized model systems that enable robust culture of primary human intestinal cells with bacteria facilitate evaluation of potential treatments. Here, we describe a protocol that can be used to coculture a primary human colon monolayer with aerotolerant bacteria. Primary human colon cells maintained as organoids are dispersed into single-cell suspensions and then seeded on collagen-coated Transwell inserts, where they attach and proliferate to form confluent monolayers within days of seeding. The confluent monolayers are differentiated for an additional 4 d and then cocultured with bacteria. As an example application, we describe how to coculture differentiated colon cells for 8 h with four strains of Bacteroides thetaiotaomicron, each engineered to detect different colonic microenvironments via genetically embedded logic circuits incorporating deoxycholic acid and anhydrotetracycline sensors. Characterization of this coculture system reveals that barrier function remains intact in the presence of engineered B. thetaiotaomicron. The bacteria stay close to the mucus layer and respond in a microenvironment-specific manner to the inducers (deoxycholic acid and anhydrotetracycline) of the genetic circuits. This protocol thus provides a useful mucosal barrier system to assess the effects of bacterial cells that respond to the colonic microenvironment, and may also be useful in other contexts to model human intestinal barrier properties and microbiota-host interactions.


Assuntos
Bacteroides thetaiotaomicron/fisiologia , Colo/citologia , Células Epiteliais/fisiologia , Mucosa Intestinal/citologia , Técnicas de Cocultura/métodos , Humanos , Organoides
14.
J Pediatr Endocrinol Metab ; 34(4): 517-520, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33818043

RESUMO

BACKGROUND: X-linked adrenoleukodystrophy (ALD) affects up to 25% of boys diagnosed with adrenal insufficiency in childhood. Because early identification of these individuals can be lifesaving, all boys with new-onset primary adrenal insufficiency should be tested for ALD with a plasma very long-chain fatty acid (VLCFA) level. While plasma VLCFA is a diagnostic test with high sensitivity and specificity, false-positive results have been reported in individuals on a ketogenic diet. CASE PRESENTATION: We present a case of an 11-year-old boy with new-onset primary adrenal insufficiency due to autoimmune adrenalitis who was initially found to have elevated VLCFA levels, suggestive of ALD, that normalized on repeat testing. CONCLUSIONS: As advances in gene therapy and newborn screening for ALD expand, VLCFA testing may increase, and clinicians should be aware that testing during the initial presentation of primary adrenal insufficiency may lead to false-positive results and associated psychosocial distress.


Assuntos
Ácidos Graxos/sangue , Tireoidite Autoimune/sangue , Doença de Addison/sangue , Criança , Creatina Quinase/sangue , Diagnóstico Diferencial , Dieta Cetogênica , Diagnóstico Precoce , Reações Falso-Positivas , Humanos , Recém-Nascido , Masculino , Triagem Neonatal , Sensibilidade e Especificidade , Tireoidite Autoimune/diagnóstico , Tireoidite Autoimune/tratamento farmacológico
15.
Stem Cells ; 39(3): 296-305, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33438789

RESUMO

Skeletal progenitor/stem cells (SSCs) play a critical role in postnatal bone growth and maintenance. Telomerase (Tert) activity prevents cellular senescence and is required for maintenance of stem cells in self-renewing tissues. Here we investigated the role of mTert-expressing cells in postnatal mouse long bone and found that mTert expression is enriched at the time of adolescent bone growth. mTert-GFP+ cells were identified in regions known to house SSCs, including the metaphyseal stroma, growth plate, and the bone marrow. We also show that mTert-expressing cells are a distinct SSC population with enriched colony-forming capacity and contribute to multiple mesenchymal lineages, in vitro. In contrast, in vivo lineage-tracing studies identified mTert+ cells as osteochondral progenitors and contribute to the bone-forming cell pool during endochondral bone growth with a subset persisting into adulthood. Taken together, our results show that mTert expression is temporally regulated and marks SSCs during a discrete phase of transitional growth between rapid bone growth and maintenance.


Assuntos
Células Epiteliais/metabolismo , Células-Tronco/metabolismo , Telomerase/metabolismo , Animais , Medula Óssea/metabolismo , Ciclo Celular/fisiologia , Proliferação de Células/fisiologia , Senescência Celular/fisiologia , Camundongos
16.
Cell Mol Bioeng ; 13(5): 487-505, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33184579

RESUMO

INTRODUCTION: The intestinal epithelium contains specialized cells including enterocytes, goblet, Paneth, enteroendocrine, and stem cells. Impaired barrier integrity in Inflammatory Bowel Disease is characterized by elevated levels of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α). Prior studies in immortalized lines such as Caco-2, without native epithelial heterogeneity, demonstrate the amelioration of TNF-α compromised barrier integrity via nicotinic (nAChR) or muscarinic (mAChR) acetylcholine receptor activation. METHODS: A tissue-engineered model of primary human small intestinal epithelium was derived from dissociated organoids cultured on collagen-coated Transwells. Differentiation was accomplished with serum-containing media and compared to Caco-2 and HT-29 regarding alkaline phosphatase expression, transepithelial electrical resistance (TEER), and IL-8 secretion. Inflammation was modeled via basal stimulation with TNF-α (25 ng/mL) with or without nicotine (nAChR agonist) or bethanechol (mAChR agonist). Apoptosis, density (cells/cm2), TEER, lucifer yellow permeability, 70 kDa dextran transport, cell morphology, and IL-8 secretion were characterized. RESULTS: Primary intestinal epithelium demonstrates significant functional differences compared to immortalized cells, including increased barrier integrity, IL-8 expression, mucus production, and the presence of absorptive and secretory cells. Exposure to TNF-α impaired barrier integrity, increased apoptosis, altered morphology, and increased secretion of IL-8. Stimulation of nAChR with nicotine did not ameliorate TNF-α induced permeability nor alter 70 kDa dextran transport. However, stimulation of mAChR with bethanechol decreased transport of 70 kDa dextran but did not ameliorate TNF-α induced paracellular permeability. CONCLUSIONS: A primary model of intestinal inflammation was evaluated, demonstrating nAChR or mAChR activation does not have the same protective effects compared to immortalized epithelium. Inclusion of other native stromal support cells are underway.

17.
Med Oncol ; 37(11): 105, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33079257

RESUMO

Osteosarcoma (OS) is the most common primary bone malignancy with high rates of recurrence and metastasis. OS often spreads to lungs, an optimized model for studying lung metastatic OS cells may help develop potential therapies for patients with lung metastasis. Here we firstly report an organoid culture system for lung metastatic OS tissues. We provided a fully described formula that was required for establishing lung metastatic OS organoids (OSOs). Using this protocol, the lung OSOs were able to be maintained and serially propagated for at least six months; the OSOs can also be generated from cryopreserved patient samples without damaging the morphology. The patient-derived lung OSOs retained the cellular morphology and expression of OS markers (Vimentin and Sox9) that recapitulate the histological features of the human OS. The microenvironment of primary lung metastatic OSOs preserved a similar T cell distribution with the human lung OS lesions; this provided a possible condition to explore how OS cells may react to immunotherapy. OSOs established from this protocol can be further utilized for studying various aspects of OS biology (e.g., tumorigenesis and drug screen/discovery) for precision medicine.


Assuntos
Neoplasias Ósseas/patologia , Neoplasias Pulmonares/patologia , Organoides/patologia , Osteossarcoma/patologia , Técnicas de Cultura de Tecidos/métodos , Adolescente , Adulto , Biomarcadores Tumorais/metabolismo , Criança , Feminino , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Organoides/efeitos dos fármacos , Organoides/metabolismo , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Linfócitos T/efeitos dos fármacos , Linfócitos T/patologia
18.
Oncogene ; 39(30): 5282-5291, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32561853

RESUMO

Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy with limited therapeutic options. The lack of mouse models that recapitulate the genetics of ACC has hampered progress in the field. We analyzed The Cancer Genome Atlas (TCGA) dataset for ACC and found that patients harboring alterations in both p53/Rb and Wnt/ß-catenin signaling pathways show a worse prognosis compared with patients that harbored alterations in only one. To model this, we utilized the Cyp11b2(AS)Cre mouse line to generate mice with adrenocortical-specific Wnt/ß-catenin activation, Trp53 deletion, or the combination of both. Mice with targeted Wnt/ß-catenin activation or Trp53 deletion showed no changes associated with tumor formation. In contrast, alterations in both pathways led to ACC with pulmonary metastases. Similar to ACCs in humans, these tumors produced increased levels of corticosterone and aldosterone and showed a high proliferation index. Gene expression analysis revealed that mouse tumors exhibited downregulation of Star and Cyp11b1 and upregulation of Ezh2, similar to ACC patients with a poor prognosis. Altogether, these data show that altering both Wnt/ß-catenin and p53/Rb signaling is sufficient to drive ACC in mouse. This autochthonous model of ACC represents a new tool to investigate the biology of ACC and to identify new treatment strategies.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Modelos Animais de Doenças , Proteína Supressora de Tumor p53/genética , Via de Sinalização Wnt/genética , beta Catenina/genética , Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/patologia , Animais , Proliferação de Células/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Camundongos Knockout , Camundongos Transgênicos , Prognóstico
19.
Biomaterials ; 254: 120125, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32502894

RESUMO

Epithelial organoids derived from human donor tissues are important tools in fields ranging from regenerative medicine to drug discovery. Organoid culture requires expansion of stem/progenitor cells in Matrigel, a tumor-derived extracellular matrix (ECM). An alternative completely synthetic ECM could improve reproducibility, clarify mechanistic phenomena, and enable human implantation of organoids. We designed synthetic ECMs with tunable biomolecular and biophysical properties to identify gel compositions supporting human tissue-derived stem/progenitor epithelial cells as enteroids and organoids starting with single cells rather than tissue fragments. The synthetic ECMs consist of 8-arm PEG-macromers modified with ECM-binding peptides and different combinations of integrin-binding peptides, crosslinked with peptides susceptible to matrix metalloprotease (MMP) degradation, and tuned to exhibit a range of biophysical properties. A gel containing an α2ß1 integrin-binding peptide (GFOGER) and matrix binder peptides grafted to a 20 kDa 8-arm PEG macromer showed the most robust support of human duodenal and colon enteroids and endometrial organoids. In this synthetic ECM, human intestinal enteroids and endometrial organoids emerge from single cells and show cell-specific and apicobasal polarity markers upon differentiation. Intestinal enteroids, in addition, retain their proliferative capacity, are functionally responsive to basolateral stimulation, express canonical markers of intestinal crypt cells including Paneth cells, and can be serially passaged. The success of this synthetic ECM in supporting human postnatal organoid culture from multiple different donors and from both the intestine and endometrium suggests it may be broadly useful for other epithelial organoid culture.


Assuntos
Intestinos , Organoides , Endométrio , Feminino , Humanos , Reprodutibilidade dos Testes , Células-Tronco
20.
Nat Commun ; 11(1): 1680, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245949

RESUMO

Rosettes are widely used in epithelial morphogenesis during embryonic development and organogenesis. However, their role in postnatal development and adult tissue maintenance remains largely unknown. Here, we show zona glomerulosa cells in the adult adrenal cortex organize into rosettes through adherens junction-mediated constriction, and that rosette formation underlies the maturation of adrenal glomerular structure postnatally. Using genetic mouse models, we show loss of ß-catenin results in disrupted adherens junctions, reduced rosette number, and dysmorphic glomeruli, whereas ß-catenin stabilization leads to increased adherens junction abundance, more rosettes, and glomerular expansion. Furthermore, we uncover numerous known regulators of epithelial morphogenesis enriched in ß-catenin-stabilized adrenals. Among these genes, we show Fgfr2 is required for adrenal rosette formation by regulating adherens junction abundance and aggregation. Together, our data provide an example of rosette-mediated postnatal tissue morphogenesis and a framework for studying the role of rosettes in adult zona glomerulosa tissue maintenance and function.


Assuntos
Junções Aderentes/metabolismo , Morfogênese , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Zona Glomerulosa/crescimento & desenvolvimento , beta Catenina/metabolismo , Junções Aderentes/genética , Junções Aderentes/ultraestrutura , Neoplasias das Glândulas Suprarrenais/cirurgia , Animais , Animais Recém-Nascidos , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Zona Glomerulosa/citologia , Zona Glomerulosa/metabolismo , Zona Glomerulosa/ultraestrutura , beta Catenina/genética
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