RESUMEN

There is a paucity of human models to study immune-mediated host damage. Here, we utilized the GeoMx spatial multi-omics platform to analyze immune cell changes in COVID-19 pancreatic autopsy samples, revealing an accumulation of proinflammatory macrophages. Single-cell RNA sequencing (scRNA-seq) analysis of human islets exposed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or coxsackievirus B4 (CVB4) viruses identified activation of proinflammatory macrophages and ß cell pyroptosis. To distinguish viral versus proinflammatory-macrophage-mediated ß cell pyroptosis, we developed human pluripotent stem cell (hPSC)-derived vascularized macrophage-islet (VMI) organoids. VMI organoids exhibited enhanced marker expression and function in both ß cells and endothelial cells compared with separately cultured cells. Notably, proinflammatory macrophages within VMI organoids induced ß cell pyroptosis. Mechanistic investigations highlighted TNFSF12-TNFRSF12A involvement in proinflammatory-macrophage-mediated ß cell pyroptosis. This study established hPSC-derived VMI organoids as a valuable tool for studying immune-cell-mediated host damage and uncovered the mechanism of ß cell damage during viral exposure.

RESUMEN

There is a paucity of human models to study immune-mediated host damage. Here, we utilized the GeoMx spatial multi-omics platform to analyze immune cell changes in COVID-19 pancreatic autopsy samples, revealing an accumulation of proinflammatory macrophages. Single cell RNA-seq analysis of human islets exposed to SARS-CoV-2 or Coxsackievirus B4 (CVB4) viruses identified activation of proinflammatory macrophages and ß cell pyroptosis. To distinguish viral versus proinflammatory macrophage-mediated ß cell pyroptosis, we developed human pluripotent stem cell (hPSC)-derived vascularized macrophage-islet (VMI) organoids. VMI organoids exhibited enhanced marker expression and function in both ß cells and endothelial cells compared to separately cultured cells. Notably, proinflammatory macrophages within VMI organoids induced ß cell pyroptosis. Mechanistic investigations highlighted TNFSF12-TNFRSF12A involvement in proinflammatory macrophage-mediated ß cell pyroptosis. This study established hPSC-derived VMI organoids as a valuable tool for studying immune cell-mediated host damage and uncovered mechanism of ß cell damage during viral exposure.

RESUMEN

Liver tumour-initiating cells (TICs) contribute to tumour initiation, metastasis, progression and drug resistance. Metabolic reprogramming is a cancer hallmark and plays vital roles in liver tumorigenesis. However, the role of metabolic reprogramming in TICs remains poorly explored. Here, we identify a mitochondria-encoded circular RNA, termed mcPGK1 (mitochondrial circRNA for translocating phosphoglycerate kinase 1), which is highly expressed in liver TICs. mcPGK1 knockdown impairs liver TIC self-renewal, whereas its overexpression drives liver TIC self-renewal. Mechanistically, mcPGK1 regulates metabolic reprogramming by inhibiting mitochondrial oxidative phosphorylation (OXPHOS) and promoting glycolysis. This alters the intracellular levels of α-ketoglutarate and lactate, which are modulators in Wnt/ß-catenin activation and liver TIC self-renewal. In addition, mcPGK1 promotes PGK1 mitochondrial import via TOM40 interactions, reprogramming metabolism from oxidative phosphorylation to glycolysis through PGK1-PDK1-PDH axis. Our work suggests that mitochondria-encoded circRNAs represent an additional regulatory layer controlling mitochondrial function, metabolic reprogramming and liver TIC self-renewal.

Asunto(s)

Hígado , Fosforilación Oxidativa , Humanos , Carcinogénesis , Ácido Láctico , Mitocondrias , ARN Circular , ARN Mitocondrial , Fosfoglicerato Quinasa/genética

RESUMEN

Colorectal cancer stem cells (CSCs) contribute to colorectal tumorigenesis and metastasis. Colorectal CSCs reside within specialized niches and harbor self-renewal and differentiation capacities. However, the niche regulations of CSCs remain unclear. Here, we show that intestinal nerve cells are required for CSC self-renewal and colorectal tumorigenesis. Enteric serotonergic neurons produce 5-hydroxytryptamine (5-HT) to function as a modulator of CSC self-renewal. 5-HT receptors HTR1B/1D/1F are highly expressed in colorectal CSCs and engage with 5-HT to initiate Wnt/ß-catenin signaling. Mechanistically, colorectal cancer (CRC)-enriched microbiota metabolite isovalerate suppresses the enrichment of the NuRD complex onto Tph2 promoter to initiate Tph2 expression, leading to 5-HT production. 5-HT signaling is correlated with CRC severity. Blocking 5-HT signaling in mice not only inhibits the self-renewal of colorectal CSCs but also displays therapeutic efficacy against CRC tumors. Our findings reveal a cross talk between intestinal neurons and tumor cells that serves as an additional layer for CSC regulation.

Asunto(s)

Autorrenovación de las Células , Neoplasias Colorrectales , Animales , Carcinogénesis , Línea Celular Tumoral , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Ratones , Neuronas Serotoninérgicas/metabolismo , Serotonina , Vía de Señalización Wnt

RESUMEN

Lgr5+ intestinal stem cells (ISCs) reside within specialized niches at the crypt base and harbor self-renewal and differentiation capacities. ISCs in the crypt base are sustained by their surrounding niche for precise modulation of self-renewal and differentiation. However, how intestinal cells in the crypt niche and microbiota in enteric cavity coordinately regulate ISC stemness remains unclear. Here, we show that ISCs are regulated by microbiota and niche enteric serotonergic neurons. The gut microbiota metabolite valeric acid promotes Tph2 expression in enteric serotonergic neurons via blocking the recruitment of the NuRD complex onto Tph2 promoter. 5-hydroxytryptamine (5-HT) in turn activates PGE2 production in a PGE2+ macrophage subset through its receptors HTR2A/3 A; and PGE2 via binding its receptors EP1/EP4, promotes Wnt/ß-catenin signaling in ISCs to promote their self-renewal. Our findings illustrate a complex crosstalk among microbiota, intestinal nerve cells, intestinal immune cells and ISCs, revealing a new layer of ISC regulation by niche cells and microbiota.

Asunto(s)

Microbioma Gastrointestinal , Autorrenovación de las Células , Dinoprostona/metabolismo , Mucosa Intestinal/metabolismo , Intestinos , Macrófagos , Neuronas Serotoninérgicas , Células Madre

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most intractable tumors in the world due to its high rate of recurrence and heterogeneity. Liver cancer initiating cells also called cancer stem cells (CSCs) play a critical role in resistance against typical therapy and high tumor-initiating potential. However, the role of the novel circular RNA (circRNA) circIPO11 in the maintenance of liver cancer initiating cells remains elusive. METHODS: CircRNAs highly conserved in humans and mice were identified from 3 primary HCC samples by circRNA array. The expression and function of circIPO11 were further evaluated by Northern blot, limiting dilution xenograft analysis, chromatin isolation by RNA purification-PCR assay (ChIRP) and HCC patient-derived tumor cells (PDC) models. CircIpo11 knockout (KO) mice were generated by a CRISPR/Cas9 technology. RESULTS: CircIPO11 is highly expressed in HCC tumor tissues and liver CSCs. CircIPO11 is required for the self-renewal maintenance of liver CSCs to initiate HCC development. Mechanistically, circIPO11 recruits TOP1 to GLI1 promoter to trigger its transcription, leading to the activation of Hedgehog signaling. Moreover, GLI1 is also highly expressed in HCC tumor tissues and liver CSCs, and TOP1 expression levels positively correlate with the metastasis, recurrence and survival of HCC patients. Additionally, circIPO11 knockout in mice suppresses the progression of chemically induced liver cancer development. CONCLUSION: Our findings reveal that circIPO11 drives the self-renewal of liver CSCs and promotes the propagation of HCC via activating Hedgehog signaling pathway. Antisense oligonucleotides (ASOs) against circIPO11 combined with TOP1 inhibitor camptothecin (CPT) exert synergistic antitumor effect. Therefore, circIPO11 and the Hedgehog signaling pathway may provide new potential targets for the treatment of HCC patients.

Asunto(s)

Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Autorrenovación de las Células/genética , Proteínas Hedgehog/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Células Madre Neoplásicas/metabolismo , ARN Circular , beta Carioferinas/genética , Animales , Biomarcadores de Tumor , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Dosificación de Gen , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/patología , Ratones , Ratones Noqueados , Células Madre Neoplásicas/patología , Regiones Promotoras Genéticas , Transducción de Señal

RESUMEN

Liver tumor-initiating cells (TICs) are involved in liver tumorigenesis, metastasis, drug resistance, and relapse, but the regulatory mechanisms of liver TICs are largely unknown. Here, we have identified a functional circular RNA, termed circRNA activating MAFF (cia-MAF), that is robustly expressed in liver cancer and liver TICs. cia-MAF-KO primary cells and cia-maf-KO liver tumors harbor decreased ratios of TICs, and display impaired liver tumorigenesis, self-renewal, and metastatic capacities. In contrast, cia-MAF overexpression drives liver TIC propagation, self-renewal, and metastasis. Mechanistically, cia-MAF binds to the MAFF promoter, recruits the TIP60 complex to the MAFF promoter, and finally promotes MAFF expression. Loss of cia-MAF function attenuates the combination between the TIP60 complex and the MAFF promoter. MAFF is highly expressed in liver tumors and liver TICs, and its antisense oligo (ASO) has therapeutic potential in treating liver cancer without MAFA/MAFG gene copy number alterations (CNAs). This study reveals an additional layer for liver TIC regulation as well as circRNA function, and provides an additional target for eliminating liver TICs, especially for liver tumors without MAFA/MAFG gene CNAs.

Asunto(s)

Autorrenovación de las Células , Neoplasias Hepáticas/etiología , Factor de Transcripción MafF/fisiología , Células Madre Neoplásicas/fisiología , ARN Circular/fisiología , Animales , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Lisina Acetiltransferasa 5/genética , Lisina Acetiltransferasa 5/fisiología , Factor de Transcripción MafF/genética , Ratones , Ratones Endogámicos C57BL , Metástasis de la Neoplasia , Regiones Promotoras Genéticas

RESUMEN

Group 3 innate lymphoid cells (ILC3s) play critical roles in innate immunity and gut homeostasis. However, how ILC3 homeostasis is regulated remains elusive. Here, we identified a novel circular RNA, circZbtb20, that is highly expressed in ILC3s and required for their maintenance and function. CircZbtb20 deletion causes reduced ILC3 numbers, increasing susceptibility to C. rodentium infection. Mechanistically, circZbtb20 enhances the interaction of Alkbh5 with Nr4a1 mRNA, leading to ablation of the m6A modification of Nr4a1 mRNA to promote its stability. Nr4a1 initiates Notch2 signaling activation, which contributes to the maintenance of ILC3 homeostasis. Deletion of Alkbh5 or Nr4a1 also impairs ILC3 homeostasis and increases susceptibilities to bacterial infection. Thus, our findings reveal an important role of circular RNA in the regulation of innate lymphoid cell homeostasis.

Asunto(s)

Adenosina/análogos & derivados , Desmetilasa de ARN, Homólogo 5 de AlkB/metabolismo , Desmetilación , Homeostasis , Inmunidad Innata/genética , Linfocitos/metabolismo , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , ARN Circular/metabolismo , Adenosina/metabolismo , Animales , Proliferación Celular , Supervivencia Celular , Tracto Gastrointestinal/inmunología , Ratones Noqueados , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Unión Proteica , Estabilidad del ARN , ARN Circular/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptor Notch2/metabolismo , Transducción de Señal

RESUMEN

Group 3 innate lymphoid cells (ILC3) are an important regulator for immunity, inflammation and tissue homeostasis in the intestine, but how ILC3 activation is regulated remains elusive. Here we identify a new circular RNA (circRNA) circKcnt2 that is induced in ILC3s during intestinal inflammation. Deletion of circKcnt2 causes gut ILC3 activation and severe colitis in mice. Mechanistically, circKcnt2, as a nuclear circRNA, recruits the nucleosome remodeling deacetylase (NuRD) complex onto Batf promoter to inhibit Batf expression; this in turn suppresses Il17 expression and thereby ILC3 inactivation to promote innate colitis resolution. Furthermore, Mbd3-/-Rag1-/- and circKcnt2-/-Rag1-/- mice develop severe innate colitis following dextran sodium sulfate (DSS) treatments, while simultaneous deletion of Batf promotes colitis resolution. In summary, our data support a function of the circRNA circKcnt2 in regulating ILC3 inactivation and resolution of innate colitis.

Asunto(s)

Colitis/inmunología , Colitis/metabolismo , Linfocitos/metabolismo , Canales de potasio activados por Sodio/metabolismo , ARN Circular/metabolismo , Animales , Colitis/patología , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Femenino , Proteínas de Homeodominio/genética , Homeostasis , Humanos , Inmunidad Innata , Inflamación/inmunología , Inflamación/patología , Intestinos/patología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Noqueados , Canales de potasio activados por Sodio/genética , ARN Circular/genética , ARN no Traducido/genética , ARN no Traducido/metabolismo , Factores de Transcripción/genética

RESUMEN

Innate lymphoid cells (ILCs) play critical roles in defending infections and maintaining mucosal homeostasis. All ILCs arise from common lymphoid progenitors (CLPs) in bone marrow. However, how CLPs stratify and differentiate into ILC lineages remains elusive. Here, we showed that Yeats4 is highly expressed in ILCs and their progenitors. Yeats4 conditional KO in the hematopoietic system causes decreased numbers of ILCs and impairs their effector functions. Moreover, Yeats4 regulates α4ß7 + CLP differentiation toward common helper ILC progenitors (CHILPs). Mechanistically, Yeats4 recruits the Dot1l-RNA Pol II complex onto Lmo4 promoter through recognizing H3K27ac modification to initiate Lmo4 transcription in α4ß7 + CLPs. Additionally, Lmo4 deficiency also impairs ILC lineage differentiation and their effector functions. Collectively, the Yeats4-Lmo4 axis is required for ILC lineage commitment.

Asunto(s)

Proteínas Adaptadoras Transductoras de Señales/genética , Linaje de la Célula/genética , Proteínas con Dominio LIM/genética , Linfocitos/metabolismo , Factores de Transcripción/genética , Transcripción Genética , Proteínas Adaptadoras Transductoras de Señales/deficiencia , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Diferenciación Celular/genética , Femenino , Proteínas con Dominio LIM/deficiencia , Proteínas con Dominio LIM/metabolismo , Linfocitos/citología , Células Progenitoras Linfoides/citología , Células Progenitoras Linfoides/metabolismo , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Noqueados , Ratones Transgénicos , Factores de Transcripción/metabolismo

RESUMEN

Intestinal stem cells (ISCs) are maintained by stemness signaling for precise modulation of self-renewal and differentiation under homeostasis. However, the way in which intestinal immune cells regulate the self-renewal of ISCs remains elusive. Here we found that mouse and human Lgr5+ ISCs showed high expression of the immune cell-associated circular RNA circPan3 (originating from the Pan3 gene transcript). Deletion of circPan3 in Lgr5+ ISCs impaired their self-renewal capacity and the regeneration of gut epithelium in a manner dependent on immune cells. circPan3 bound mRNA encoding the cytokine IL-13 receptor subunit IL-13Rα1 (Il13ra1) in ISCs to increase its stability, which led to the expression of IL-13Rα1 in ISCs. IL-13 produced by group 2 innate lymphoid cells in the crypt niche engaged IL-13Rα1 on crypt ISCs and activated signaling mediated by IL-13‒IL-13R, which in turn initiated expression of the transcription factor Foxp1. Foxp1 is associated with ß-catenin in rendering its nuclear translocation, which caused activation of the ß-catenin pathway and the maintenance of Lgr5+ ISCs.

Asunto(s)

Autorrenovación de las Células/inmunología , Interleucina-13/metabolismo , Mucosa Intestinal/inmunología , ARN/metabolismo , Células Madre/fisiología , Animales , Proteínas Portadoras/genética , Diferenciación Celular/inmunología , Autorrenovación de las Células/genética , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/inmunología , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Femenino , Humanos , Interleucina-13/inmunología , Subunidad alfa1 del Receptor de Interleucina-13/genética , Subunidad alfa1 del Receptor de Interleucina-13/inmunología , Subunidad alfa1 del Receptor de Interleucina-13/metabolismo , Mucosa Intestinal/citología , Mucosa Intestinal/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Noqueados , ARN/genética , ARN/inmunología , ARN Circular , ARN Mensajero/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Regeneración/genética , Regeneración/inmunología , Transducción de Señal/genética , Transducción de Señal/inmunología , beta Catenina/inmunología , beta Catenina/metabolismo

RESUMEN

BACKGROUND & AIMS: Liver cancer is the second leading cause of cancer death worldwide. Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults. The aim of this study was to define the role of the long non-coding RNA lncHDAC2 in the tumorigenesis of HCC. METHODS: CD13+CD133+ cells (hereafter called liver cancer stem cells [CSCs]) and CD13-CD133- cells (referred to as non-CSCs) were sorted from 3 primary HCC tumor tissues and followed by transcriptome microarray. The expression and function of lncHDAC2 were further assessed by northern blot, sphere formation and xenograft tumor models. RESULTS: LncHDAC2 is highly expressed in HCC tumors and liver CSCs. LncHDAC2 promotes the self-renewal of liver CSCs and tumor propagation. In liver CSCs, lncHDAC2 recruits the NuRD complex onto the promoter of PTCH1 to inhibit its expression, leading to activation of Hedgehog signaling. Moreover, HDAC2 expression levels are positively related to HCC severity and PTCH1 levels are negatively related to HCC severity. Additionally, the Smo inhibitor cyclopamine was shown to impair the self-renewal of liver CSCs and suppress tumor propagation. CONCLUSION: Our findings reveal that lncHDAC2 promotes the self-renewal of liver CSCs and tumor propagation by activating the Hedgehog signaling pathway. Downregulating lncHDAC2 is a promising antitumor strategy in HCC. LAY SUMMARY: Liver cancer stem cells harbor high tumor-initiating potential and confer resistance to typical therapies, but the mechanism underlying their self-renewal remains elusive. LncHDAC2 augments the self-renewal of these cells, promoting tumor propagation. In liver cancer stem cells, lncHDAC2 activates Hedgehog signaling to initiate liver tumorigenesis. Therefore, lncHDAC2 and the Hedgehog signaling pathway may serve as biomarkers and potential drug targets for hepatocellular carcinoma.

Asunto(s)

Autorrenovación de las Células , Proteínas Hedgehog/fisiología , Histona Desacetilasa 2/genética , Neoplasias Hepáticas/patología , Células Madre Neoplásicas/fisiología , ARN Largo no Codificante/fisiología , Transducción de Señal , Línea Celular Tumoral , Humanos , Receptor Patched-1/genética , Regiones Promotoras Genéticas , Transducción de Señal/fisiología

RESUMEN

The intestinal epithelium harbours remarkable self-renewal capacity that is driven by Lgr5+ intestinal stem cells (ISCs) at the crypt base. However, the molecular mechanism controlling Lgr5+ ISC stemness is incompletely understood. We show that a Gata6 long noncoding RNA (lncGata6) is highly expressed in ISCs. LncGata6 knockout or conditional knockout in ISCs impairs the stemness of ISCs and epithelial regeneration. Mechanistically, lncGata6 recruits the NURF complex onto the Ehf promoter to induce its transcription, which promotes the expression of Lgr4/5 to enhance Wnt signalling activation. Moreover, the human orthologue lncGATA6 is highly expressed in the cancer stem cells of colorectal cancer and promotes tumour initiation and progression. Antisense oligonucleotides against lncGATA6 exhibit strong therapeutic efficacy on colorectal cancer. Thus, targeting lncGATA6 will have potential clinical applications in colorectal cancer treatment as an ideal therapeutic target.

Asunto(s)

Transformación Celular Neoplásica/genética , Mucosa Intestinal/metabolismo , ARN Largo no Codificante/genética , Células Madre/metabolismo , Animales , Transformación Celular Neoplásica/metabolismo , Células Cultivadas , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Perfilación de la Expresión Génica/métodos , Humanos , Mucosa Intestinal/citología , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Ratones Transgénicos , ARN Largo no Codificante/metabolismo , Trasplante Heterólogo , Células Tumorales Cultivadas