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1.
Cell ; 171(2): 358-371.e9, 2017 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-28985563

RESUMEN

Cancer cells consume glucose and secrete lactate in culture. It is unknown whether lactate contributes to energy metabolism in living tumors. We previously reported that human non-small-cell lung cancers (NSCLCs) oxidize glucose in the tricarboxylic acid (TCA) cycle. Here, we show that lactate is also a TCA cycle carbon source for NSCLC. In human NSCLC, evidence of lactate utilization was most apparent in tumors with high 18fluorodeoxyglucose uptake and aggressive oncological behavior. Infusing human NSCLC patients with 13C-lactate revealed extensive labeling of TCA cycle metabolites. In mice, deleting monocarboxylate transporter-1 (MCT1) from tumor cells eliminated lactate-dependent metabolite labeling, confirming tumor-cell-autonomous lactate uptake. Strikingly, directly comparing lactate and glucose metabolism in vivo indicated that lactate's contribution to the TCA cycle predominates. The data indicate that tumors, including bona fide human NSCLC, can use lactate as a fuel in vivo.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Ácido Láctico/metabolismo , Neoplasias Pulmonares/metabolismo , Animales , Análisis Químico de la Sangre , Línea Celular Tumoral , Ciclo del Ácido Cítrico , Modelos Animales de Enfermedad , Femenino , Ácidos Glicéricos/metabolismo , Xenoinjertos , Humanos , Masculino , Ratones , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Trasplante de Neoplasias , Simportadores/genética , Simportadores/metabolismo
2.
Nature ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143213

RESUMEN

Most kidney cancers are metabolically dysfunctional1-4, but how this dysfunction affects cancer progression in humans is unknown. We infused 13C-labelled nutrients in over 80 patients with kidney cancer during surgical tumour resection. Labelling from [U-13C]glucose varies across subtypes, indicating that the kidney environment alone cannot account for all tumour metabolic reprogramming. Compared with the adjacent kidney, clear cell renal cell carcinomas (ccRCCs) display suppressed labelling of tricarboxylic acid (TCA) cycle intermediates in vivo and in ex vivo organotypic cultures, indicating that suppressed labelling is tissue intrinsic. [1,2-13C]acetate and [U-13C]glutamine infusions in patients, coupled with measurements of respiration in isolated human kidney and tumour mitochondria, reveal lower electron transport chain activity in ccRCCs that contributes to decreased oxidative and enhanced reductive TCA cycle labelling. However, ccRCC metastases unexpectedly have enhanced TCA cycle labelling compared with that of primary ccRCCs, indicating a divergent metabolic program during metastasis in patients. In mice, stimulating respiration or NADH recycling in kidney cancer cells is sufficient to promote metastasis, whereas inhibiting electron transport chain complex I decreases metastasis. These findings in humans and mice indicate that metabolic properties and liabilities evolve during kidney cancer progression, and that mitochondrial function is limiting for metastasis but not growth at the original site.

3.
Cell ; 159(7): 1591-602, 2014 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-25525877

RESUMEN

Acetyl-CoA represents a central node of carbon metabolism that plays a key role in bioenergetics, cell proliferation, and the regulation of gene expression. Highly glycolytic or hypoxic tumors must produce sufficient quantities of this metabolite to support cell growth and survival under nutrient-limiting conditions. Here, we show that the nucleocytosolic acetyl-CoA synthetase enzyme, ACSS2, supplies a key source of acetyl-CoA for tumors by capturing acetate as a carbon source. Despite exhibiting no gross deficits in growth or development, adult mice lacking ACSS2 exhibit a significant reduction in tumor burden in two different models of hepatocellular carcinoma. ACSS2 is expressed in a large proportion of human tumors, and its activity is responsible for the majority of cellular acetate uptake into both lipids and histones. These observations may qualify ACSS2 as a targetable metabolic vulnerability of a wide spectrum of tumors.


Asunto(s)
Acetato CoA Ligasa/metabolismo , Acetatos/metabolismo , Neoplasias/metabolismo , Acetato CoA Ligasa/análisis , Acetato CoA Ligasa/genética , Acetilcoenzima A/metabolismo , Animales , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/metabolismo , Ratones , Neoplasias/química , Neoplasias/patología , Tomografía de Emisión de Positrones , Neoplasias de la Mama Triple Negativas/química , Neoplasias de la Mama Triple Negativas/patología
4.
Nature ; 623(7987): 633-642, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37938770

RESUMEN

Trimethylation of histone H3 lysine 9 (H3K9me3) is crucial for the regulation of gene repression and heterochromatin formation, cell-fate determination and organismal development1. H3K9me3 also provides an essential mechanism for silencing transposable elements1-4. However, previous studies have shown that canonical H3K9me3 readers (for example, HP1 (refs. 5-9) and MPP8 (refs. 10-12)) have limited roles in silencing endogenous retroviruses (ERVs), one of the main transposable element classes in the mammalian genome13. Here we report that trinucleotide-repeat-containing 18 (TNRC18), a poorly understood chromatin regulator, recognizes H3K9me3 to mediate the silencing of ERV class I (ERV1) elements such as LTR12 (ref. 14). Biochemical, biophysical and structural studies identified the carboxy-terminal bromo-adjacent homology (BAH) domain of TNRC18 (TNRC18(BAH)) as an H3K9me3-specific reader. Moreover, the amino-terminal segment of TNRC18 is a platform for the direct recruitment of co-repressors such as HDAC-Sin3-NCoR complexes, thus enforcing optimal repression of the H3K9me3-demarcated ERVs. Point mutagenesis that disrupts the TNRC18(BAH)-mediated H3K9me3 engagement caused neonatal death in mice and, in multiple mammalian cell models, led to derepressed expression of ERVs, which affected the landscape of cis-regulatory elements and, therefore, gene-expression programmes. Collectively, we describe a new H3K9me3-sensing and regulatory pathway that operates to epigenetically silence evolutionarily young ERVs and exert substantial effects on host genome integrity, transcriptomic regulation, immunity and development.


Asunto(s)
Retrovirus Endógenos , Silenciador del Gen , Histonas , Péptidos y Proteínas de Señalización Intracelular , Lisina , Retroelementos , Animales , Humanos , Ratones , Cromatina/genética , Cromatina/metabolismo , Proteínas Co-Represoras/metabolismo , Retrovirus Endógenos/genética , Epigénesis Genética , Perfilación de la Expresión Génica , Genoma/genética , Histona Desacetilasas/metabolismo , Histonas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Lisina/metabolismo , Metilación , Dominios Proteicos , Retroelementos/genética , Secuencias Repetidas Terminales/genética , Animales Recién Nacidos , Línea Celular
5.
Cell ; 155(6): 1309-22, 2013 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-24315100

RESUMEN

The treatment of advanced prostate cancer has been transformed by novel antiandrogen therapies such as enzalutamide. Here, we identify induction of glucocorticoid receptor (GR) expression as a common feature of drug-resistant tumors in a credentialed preclinical model, a finding also confirmed in patient samples. GR substituted for the androgen receptor (AR) to activate a similar but distinguishable set of target genes and was necessary for maintenance of the resistant phenotype. The GR agonist dexamethasone was sufficient to confer enzalutamide resistance, whereas a GR antagonist restored sensitivity. Acute AR inhibition resulted in GR upregulation in a subset of prostate cancer cells due to relief of AR-mediated feedback repression of GR expression. These findings establish a mechanism of escape from AR blockade through expansion of cells primed to drive AR target genes via an alternative nuclear receptor upon drug exposure.


Asunto(s)
Antagonistas de Andrógenos/uso terapéutico , Antagonistas de Receptores Androgénicos/uso terapéutico , Resistencia a Antineoplásicos , Feniltiohidantoína/análogos & derivados , Neoplasias de la Próstata/tratamiento farmacológico , Receptores de Glucocorticoides/metabolismo , Animales , Benzamidas , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Xenoinjertos , Humanos , Masculino , Ratones , Trasplante de Neoplasias , Nitrilos , Feniltiohidantoína/uso terapéutico , Receptores Androgénicos/metabolismo , Transcriptoma
6.
Nature ; 604(7905): 349-353, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35388219

RESUMEN

Mammalian embryogenesis requires rapid growth and proper metabolic regulation1. Midgestation features increasing oxygen and nutrient availability concomitant with fetal organ development2,3. Understanding how metabolism supports development requires approaches to observe metabolism directly in model organisms in utero. Here we used isotope tracing and metabolomics to identify evolving metabolic programmes in the placenta and embryo during midgestation in mice. These tissues differ metabolically throughout midgestation, but we pinpointed gestational days (GD) 10.5-11.5 as a transition period for both placenta and embryo. Isotope tracing revealed differences in carbohydrate metabolism between the tissues and rapid glucose-dependent purine synthesis, especially in the embryo. Glucose's contribution to the tricarboxylic acid (TCA) cycle rises throughout midgestation in the embryo but not in the placenta. By GD12.5, compartmentalized metabolic programmes are apparent within the embryo, including different nutrient contributions to the TCA cycle in different organs. To contextualize developmental anomalies associated with Mendelian metabolic defects, we analysed mice deficient in LIPT1, the enzyme that activates 2-ketoacid dehydrogenases related to the TCA cycle4,5. LIPT1 deficiency suppresses TCA cycle metabolism during the GD10.5-GD11.5 transition, perturbs brain, heart and erythrocyte development and leads to embryonic demise by GD11.5. These data document individualized metabolic programmes in developing organs in utero.


Asunto(s)
Ciclo del Ácido Cítrico , Desarrollo Fetal , Metabolómica , Placenta , Animales , Embrión de Mamíferos/metabolismo , Femenino , Glucosa/metabolismo , Mamíferos/metabolismo , Ratones , Placenta/metabolismo , Embarazo
7.
Nature ; 595(7868): 591-595, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34163069

RESUMEN

The development of cancer is intimately associated with genetic abnormalities that target proteins with intrinsically disordered regions (IDRs). In human haematological malignancies, recurrent chromosomal translocation of nucleoporin (NUP98 or NUP214) generates an aberrant chimera that invariably retains the nucleoporin IDR-tandemly dispersed repeats of phenylalanine and glycine residues1,2. However, how unstructured IDRs contribute to oncogenesis remains unclear. Here we show that IDRs contained within NUP98-HOXA9, a homeodomain-containing transcription factor chimera recurrently detected in leukaemias1,2, are essential for establishing liquid-liquid phase separation (LLPS) puncta of chimera and for inducing leukaemic transformation. Notably, LLPS of NUP98-HOXA9 not only promotes chromatin occupancy of chimera transcription factors, but also is required for the formation of a broad 'super-enhancer'-like binding pattern typically seen at leukaemogenic genes, which potentiates transcriptional activation. An artificial HOX chimera, created by replacing the phenylalanine and glycine repeats of NUP98 with an unrelated LLPS-forming IDR of the FUS protein3,4, had similar enhancing effects on the genome-wide binding and target gene activation of the chimera. Deeply sequenced Hi-C revealed that phase-separated NUP98-HOXA9 induces CTCF-independent chromatin loops that are enriched at proto-oncogenes. Together, this report describes a proof-of-principle example in which cancer acquires mutation to establish oncogenic transcription factor condensates via phase separation, which simultaneously enhances their genomic targeting and induces organization of aberrant three-dimensional chromatin structure during tumourous transformation. As LLPS-competent molecules are frequently implicated in diseases1,2,4-7, this mechanism can potentially be generalized to many malignant and pathological settings.


Asunto(s)
Cromatina/genética , Proteínas de Homeodominio/genética , Proteínas Intrínsecamente Desordenadas/genética , Neoplasias/patología , Proteínas de Complejo Poro Nuclear/genética , Translocación Genética , Animales , Carcinogénesis , Femenino , Células HEK293 , Células HeLa , Humanos , Ratones , Ratones Endogámicos BALB C , Neoplasias/genética , Proteínas de Fusión Oncogénica/genética , Factores de Transcripción/genética , Activación Transcripcional
8.
Mol Cell ; 76(5): 838-851.e5, 2019 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-31564558

RESUMEN

Intermediary metabolism in cancer cells is regulated by diverse cell-autonomous processes, including signal transduction and gene expression patterns, arising from specific oncogenotypes and cell lineages. Although it is well established that metabolic reprogramming is a hallmark of cancer, we lack a full view of the diversity of metabolic programs in cancer cells and an unbiased assessment of the associations between metabolic pathway preferences and other cell-autonomous processes. Here, we quantified metabolic features, mostly from the 13C enrichment of molecules from central carbon metabolism, in over 80 non-small cell lung cancer (NSCLC) cell lines cultured under identical conditions. Because these cell lines were extensively annotated for oncogenotype, gene expression, protein expression, and therapeutic sensitivity, the resulting database enables the user to uncover new relationships between metabolism and these orthogonal processes.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral/metabolismo , Metaboloma/fisiología , Biomarcadores de Tumor/metabolismo , Cromatografía de Gases y Espectrometría de Masas/métodos , Regulación Neoplásica de la Expresión Génica/fisiología , Glucosa/metabolismo , Glutamina/metabolismo , Humanos , Redes y Vías Metabólicas/genética , Metabolómica/métodos , Neoplasias/metabolismo
9.
PLoS Pathog ; 20(6): e1012319, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38885290

RESUMEN

Candida albicans is a leading cause of intravascular catheter-related infections. The capacity for biofilm formation has been proposed to contribute to the persistence of this fungal pathogen on catheter surfaces. While efforts have been devoted to identifying microbial factors that modulate C. albicans biofilm formation in vitro, our understanding of the host factors that may shape C. albicans persistence in intravascular catheters is lacking. Here, we used multiphoton microscopy to characterize biofilms in intravascular catheters removed from candidiasis patients. We demonstrated that, NETosis, a type of neutrophil cell death with antimicrobial activity, was implicated in the interaction of immune cells with C. albicans in the catheters. The catheter isolates exhibited reduced filamentation and candidalysin gene expression, specifically in the total parenteral nutrition culture environment. Furthermore, we showed that the ablation of candidalysin expression in C. albicans reduced NETosis and conferred resistance to neutrophil-mediated fungal biofilm elimination. Our findings illustrate the role of neutrophil NETosis in modulating C. albicans biofilm persistence in an intravascular catheter, highlighting that C. albicans can benefit from reduced virulence expression to promote its persistence in an intravascular catheter.


Asunto(s)
Biopelículas , Candida albicans , Candidiasis , Infecciones Relacionadas con Catéteres , Trampas Extracelulares , Proteínas Fúngicas , Neutrófilos , Humanos , Biopelículas/crecimiento & desarrollo , Proteínas Fúngicas/metabolismo , Candidiasis/microbiología , Candidiasis/inmunología , Infecciones Relacionadas con Catéteres/microbiología , Neutrófilos/inmunología , Neutrófilos/metabolismo , Trampas Extracelulares/inmunología , Catéteres/microbiología , Regulación Fúngica de la Expresión Génica
10.
Annu Rev Cell Dev Biol ; 28: 59-87, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22578140

RESUMEN

For unicellular organisms, the decision to enter the cell cycle can be viewed most fundamentally as a metabolic problem. A cell must assess its nutritional and metabolic status to ensure it can synthesize sufficient biomass to produce a new daughter cell. The cell must then direct the appropriate metabolic outputs to ensure completion of the division process. Herein, we discuss the changes in metabolism that accompany entry to, and exit from, the cell cycle for the unicellular eukaryote Saccharomyces cerevisiae. Studies of budding yeast under continuous, slow-growth conditions have provided insights into the essence of these metabolic changes at unprecedented temporal resolution. Some of these mechanisms by which cell growth and proliferation are coordinated with metabolism are likely to be conserved in multicellular organisms. An improved understanding of the metabolic basis of cell cycle control promises to reveal fundamental principles governing tumorigenesis, metazoan development, niche expansion, and many additional aspects of cell and organismal growth control.


Asunto(s)
Ciclo Celular , Saccharomyces cerevisiae/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/fisiología , Metabolismo Energético , Genes Fúngicos , Redes y Vías Metabólicas , Mitosis , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/fisiología , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/fisiología
11.
Mol Cell ; 72(2): 341-354.e6, 2018 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-30270106

RESUMEN

Androgen receptor splice variant 7 (AR-V7) is crucial for prostate cancer progression and therapeutic resistance. We show that, independent of ligand, AR-V7 binds both androgen-responsive elements (AREs) and non-canonical sites distinct from full-length AR (AR-FL) targets. Consequently, AR-V7 not only recapitulates AR-FL's partial functions but also regulates an additional gene expression program uniquely via binding to gene promoters rather than ARE enhancers. AR-V7 binding and AR-V7-mediated activation at these unique targets do not require FOXA1 but rely on ZFX and BRD4. Knockdown of ZFX or select unique targets of AR-V7/ZFX, or BRD4 inhibition, suppresses growth of castration-resistant prostate cancer cells. We also define an AR-V7 direct target gene signature that correlates with AR-V7 expression in primary tumors, differentiates metastatic prostate cancer from normal, and predicts poor prognosis. Thus, AR-V7 has both ARE/FOXA1 canonical and ZFX-directed non-canonical regulatory functions in the evolution of anti-androgen therapeutic resistance, providing information to guide effective therapeutic strategies.


Asunto(s)
Empalme Alternativo/genética , Carcinogénesis/genética , Factores de Transcripción de Tipo Kruppel/genética , Oncogenes/genética , Neoplasias de la Próstata Resistentes a la Castración/genética , Receptores Androgénicos/genética , Animales , Diferenciación Celular/genética , Línea Celular , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica/genética , Células HEK293 , Factor Nuclear 3-alfa del Hepatocito/genética , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas Nucleares/genética , Regiones Promotoras Genéticas/genética
12.
Nature ; 569(7756): E4, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31043737

RESUMEN

Further analysis has revealed that the signal reported in Extended Data Fig. 1c of this Letter is attributed to phosphorylethanolamine, not carbamoyl phosphate. A newly developed derivatization method revealed that the level of carbamoyl phosphate in these NSCLC extracts is below the detection threshold of approximately 10 nanomoles. These findings do not alter the overall conclusions of the Letter; see associated Amendment for full details. The Letter has not been corrected online.

13.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35217626

RESUMEN

Acute myeloid leukemias (AMLs) with the NUP98-NSD1 or mixed lineage leukemia (MLL) rearrangement (MLL-r) share transcriptomic profiles associated with stemness-related gene signatures and display poor prognosis. The molecular underpinnings of AML aggressiveness and stemness remain far from clear. Studies with EZH2 enzymatic inhibitors show that polycomb repressive complex 2 (PRC2) is crucial for tumorigenicity in NUP98-NSD1+ AML, whereas transcriptomic analysis reveal that Kdm5b, a lysine demethylase gene carrying "bivalent" chromatin domains, is directly repressed by PRC2. While ectopic expression of Kdm5b suppressed AML growth, its depletion not only promoted tumorigenicity but also attenuated anti-AML effects of PRC2 inhibitors, demonstrating a PRC2-|Kdm5b axis for AML oncogenesis. Integrated RNA sequencing (RNA-seq), chromatin immunoprecipitation followed by sequencing (ChIP-seq), and Cleavage Under Targets & Release Using Nuclease (CUT&RUN) profiling also showed that Kdm5b directly binds and represses AML stemness genes. The anti-AML effect of Kdm5b relies on its chromatin association and/or scaffold functions rather than its demethylase activity. Collectively, this study describes a molecular axis that involves histone modifiers (PRC2-|Kdm5b) for sustaining AML oncogenesis.


Asunto(s)
Histona Demetilasas con Dominio de Jumonji/metabolismo , Leucemia Mieloide Aguda/patología , Proteínas Nucleares/metabolismo , Complejo Represivo Polycomb 2/metabolismo , Proteínas Represoras/metabolismo , Animales , Carcinogénesis , Perfilación de la Expresión Génica , Histona Demetilasas/metabolismo , Humanos , Leucemia Mieloide Aguda/metabolismo , Ratones , Proteínas Oncogénicas/metabolismo , Complejo Represivo Polycomb 2/antagonistas & inhibidores , Unión Proteica , Análisis de Secuencia de ARN/métodos
14.
Fish Shellfish Immunol ; 151: 109716, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38909636

RESUMEN

Previous studies show that bisphenol A (BPA) and its analogs induce oxidative stress and promote inflammatory response. However, the key molecules in regulating this process remain unclear. Here, we report significant inductive effects of BPA and bisphenol AF (BPAF) on a newly found long non-coding RNA linc-93.2 accompanied by oxidative stress and activation of pro-inflammatory pathways in treated fish and fish primary macrophages. Silencing linc-93.2 in fish primary macrophages in vitro or fish in vivo significantly promotes the expression of anti-oxidative stress-related genes and anti-inflammatory cytokines. This inhibition of pro-inflammatory cytokine expression, showing cell status disruption towards to M2 polarization. Followed by exposure to BPA or BPAF, silencing linc-93.2 in vitro or in vivo significantly attenuates the increased production of reactive oxygen species and malondialdehyde level aroused by bisphenol treatment, possibly owing to the enhancement of total antioxidant capacity observed in cells and tissue after linc-93.2 knockdown. RNA-sequencing further revealed regulation of nuclear factor-kappa b (NF-κB) in linc-93.2's downstream network, combining with our previous observation on the upstream regulation of linc-93.2 via NF-κB, which together suggest a critical role of linc-93.2 in promoting NF-κB positive feedback loop that may be an important molecular event initiating the immunotoxicity of bisphenols.


Asunto(s)
Compuestos de Bencidrilo , Carpas , Macrófagos , Estrés Oxidativo , Fenoles , ARN Largo no Codificante , Animales , ARN Largo no Codificante/genética , ARN Largo no Codificante/inmunología , Compuestos de Bencidrilo/toxicidad , Fenoles/toxicidad , Estrés Oxidativo/efectos de los fármacos , Carpas/genética , Carpas/inmunología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Contaminantes Químicos del Agua/toxicidad , Fluorocarburos
15.
Acta Pharmacol Sin ; 45(7): 1438-1450, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38565961

RESUMEN

Angiogenesis plays a critical role in many pathological processes, including irreversible blindness in eye diseases such as retinopathy of prematurity. Endothelial mitochondria are dynamic organelles that undergo constant fusion and fission and are critical signalling hubs that modulate angiogenesis by coordinating reactive oxygen species (ROS) production and calcium signalling and metabolism. In this study, we investigated the role of mitochondrial dynamics in pathological retinal angiogenesis. We showed that treatment with vascular endothelial growth factor (VEGF; 20 ng/ml) induced mitochondrial fission in HUVECs by promoting the phosphorylation of dynamin-related protein 1 (DRP1). DRP1 knockdown or pretreatment with the DRP1 inhibitor Mdivi-1 (5 µM) blocked VEGF-induced cell migration, proliferation, and tube formation in HUVECs. We demonstrated that VEGF treatment increased mitochondrial ROS production in HUVECs, which was necessary for HIF-1α-dependent glycolysis, as well as proliferation, migration, and tube formation, and the inhibition of mitochondrial fission prevented VEGF-induced mitochondrial ROS production. In an oxygen-induced retinopathy (OIR) mouse model, we found that active DRP1 was highly expressed in endothelial cells in neovascular tufts. The administration of Mdivi-1 (10 mg·kg-1·d-1, i.p.) for three days from postnatal day (P) 13 until P15 significantly alleviated pathological angiogenesis in the retina. Our results suggest that targeting mitochondrial fission may be a therapeutic strategy for proliferative retinopathies and other diseases that are dependent on pathological angiogenesis.


Asunto(s)
Movimiento Celular , Dinaminas , Células Endoteliales de la Vena Umbilical Humana , Subunidad alfa del Factor 1 Inducible por Hipoxia , Ratones Endogámicos C57BL , Dinámicas Mitocondriales , Quinazolinonas , Especies Reactivas de Oxígeno , Neovascularización Retiniana , Factor A de Crecimiento Endotelial Vascular , Dinámicas Mitocondriales/efectos de los fármacos , Animales , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Humanos , Especies Reactivas de Oxígeno/metabolismo , Dinaminas/metabolismo , Dinaminas/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/metabolismo , Quinazolinonas/farmacología , Neovascularización Retiniana/metabolismo , Neovascularización Retiniana/patología , Neovascularización Retiniana/tratamiento farmacológico , Movimiento Celular/efectos de los fármacos , Ratones , Proliferación Celular/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Angiogénesis
16.
Environ Res ; : 119792, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39142455

RESUMEN

The functionality of activated sludge in wastewater treatment processes depends largely on the structural and microbial composition of its flocs, which are complex assemblages of microorganisms and their secretions. However, monitoring these flocs in real-time and consistently has been challenging due to the lack of suitable technologies and analytical methods. Here we present a laboratory setup capable of capturing instantaneous microscopic images of activated sludge, along with algorithms to interpret these images. To improve floc identification, an advanced Mask R-CNN-based segmentation that integrates a Dual Attention Network (DANet) with an enhanced Feature Pyramid Network (FPN) was used to enhance feature extraction and segmentation accuracy. Additionally, our novel PointRend module meticulously refines the contours of boundaries, significantly minimising pixel inaccuracies. Impressively, our approach achieved a floc detection accuracy of >95%. This development marks a significant advancement in real-time sludge monitoring, offering essential insights for optimising wastewater treatment operations proactively.

17.
Nucleic Acids Res ; 50(19): 10929-10946, 2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36300627

RESUMEN

Enhancer of Zeste Homolog 2 (EZH2) and androgen receptor (AR) are crucial chromatin/gene regulators involved in the development and/or progression of prostate cancer, including advanced castration-resistant prostate cancer (CRPC). To sustain prostate tumorigenicity, EZH2 establishes non-canonical biochemical interaction with AR for mediating oncogene activation, in addition to its canonical role as a transcriptional repressor and enzymatic subunit of Polycomb Repressive Complex 2 (PRC2). However, the molecular basis underlying non-canonical activities of EZH2 in prostate cancer remains elusive, and a therapeutic strategy for targeting EZH2:AR-mediated oncogene activation is also lacking. Here, we report that a cryptic transactivation domain of EZH2 (EZH2TAD) binds both AR and AR spliced variant 7 (AR-V7), a constitutively active AR variant enriched in CRPC, mediating assembly and/or recruitment of transactivation-related machineries at genomic sites that lack PRC2 binding. Such non-canonical targets of EZH2:AR/AR-V7:(co-)activators are enriched for the clinically relevant oncogenes. We also show that EZH2TAD is required for the chromatin recruitment of EZH2 to oncogenes, for EZH2-mediated oncogene activation and for CRPC growth in vitro and in vivo. To completely block EZH2's multifaceted oncogenic activities in prostate cancer, we employed MS177, a recently developed proteolysis-targeting chimera (PROTAC) of EZH2. Strikingly, MS177 achieved on-target depletion of both EZH2's canonical (EZH2:PRC2) and non-canonical (EZH2TAD:AR/AR-V7:co-activators) complexes in prostate cancer cells, eliciting far more potent antitumor effects than the catalytic inhibitors of EZH2. Overall, this study reports a previously unappreciated requirement for EZH2TAD for mediating EZH2's non-canonical (co-)activator recruitment and gene activation functions in prostate cancer and suggests EZH2-targeting PROTACs as a potentially attractive therapeutic for the treatment of aggressive prostate cancer that rely on the circuits wired by EZH2 and AR.


Asunto(s)
Proteína Potenciadora del Homólogo Zeste 2 , Neoplasias de la Próstata Resistentes a la Castración , Receptores Androgénicos , Humanos , Masculino , Línea Celular Tumoral , Cromatina/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Regulación Neoplásica de la Expresión Génica , Oncogenes , Complejo Represivo Polycomb 2/genética , Complejo Represivo Polycomb 2/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Activación Transcripcional , Isoformas de Proteínas
18.
Phytother Res ; 38(4): 1951-1970, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38358770

RESUMEN

The herb Sophora flavescens displays anti-inflammatory activity and can provide a source of antipsoriatic medications. We aimed to evaluate whether S. flavescens extracts and compounds can relieve psoriasiform inflammation. The ability of flavonoids (maackiain, sophoraflavanone G, leachianone A) and alkaloids (matrine, oxymatrine) isolated from S. flavescens to inhibit production of cytokine/chemokines was examined in keratinocytes and macrophages. Physicochemical properties and skin absorption were determined by in silico molecular modeling and the in vitro permeation test (IVPT) to establish the structure-permeation relationship (SPR). The ethyl acetate extract exhibited higher inhibition of interleukin (IL)-6, IL-8, and CXCL1 production in tumor necrosis factor-α-stimulated keratinocytes compared to the ethanol and water extracts. The flavonoids demonstrated higher cytokine/chemokine inhibition than alkaloids, with the prenylated flavanones (sophoraflavanone G, leachianone A) led to the highest suppression. Flavonoids exerted anti-inflammatory effects via the extracellular signal-regulated kinase, p38, activator protein-1, and nuclear factor-κB signaling pathways. In the IVPT, prenylation of the flavanone skeleton significantly promoted skin absorption from 0.01 to 0.22 nmol/mg (sophoraflavanone G vs. eriodictyol). Further methoxylation of a prenylated flavanone (leachianone A) elevated skin absorption to 2.65 nmol/mg. Topical leachianone A reduced the epidermal thickness in IMQ-treated mice by 47%, and inhibited cutaneous scaling and cytokine/chemokine overexpression at comparable levels to a commercial betamethasone product. Thus, prenylation and methoxylation of S. flavescens flavanones may enable the design of novel antipsoriatic agents.


Asunto(s)
Alcaloides , Flavanonas , Sophora , Ratones , Animales , Flavonoides/química , Sophora flavescens , Sophora/química , Flavanonas/farmacología , Flavanonas/química , Prenilación , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Citocinas , Quimiocinas
19.
Am J Otolaryngol ; 45(6): 104476, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39163816

RESUMEN

BACKGROUND: Precision dosing in sublingual immunotherapy (SLIT) has become a hotspot gradually, yet no standardized dose adjustment pattern for house dust mite (HDM)-SLIT. This study aims to investigate the clinical feasibility of the dynamic maintenance dose ascending regimen for individualized SLIT. METHODS: A total of 258 allergic rhinitis (AR) patients treated with HDM-SLIT were included in this retrospective study. Patients were divided into the regular dose (RD) group (n = 101) and the high dose (HD) group (n = 157) according to different maintenance dosages of SLIT. In the RD group, patients received the fixed dose recommended by the manufacturer. In the HD group, patients received a maximum tolerance dose determined by dynamic dose ascending. The clinical efficacy was evaluated by combined symptom and medication score (CSMS) and visual analogue scale score (VAS) at the baseline, 0.5-year, 1-year, and 2-year. The safety was evaluated by adverse events (AEs). RESULTS: Significant reductions of CSMS and VAS at 0.5-year, 1-year, and 2-year were observed in both the RD group and the HD group compared to the baseline (P < 0.05). In addition, greater improvements in these clinical parameters from 0.5- to 2-year were found in the HD group compared to the RD group (P < 0.05). For subgroup analysis in the HD group, no significant differences in CSMS and VAS were observed among subgroups of patients <14 years old and patients ≥14 years old (P > 0.05). No serious AEs in the two groups and no significant differences were observed between the AE incidence rate of the RD group and HD group during the incremental and maintenance phases. CONCLUSIONS: The 2-year HDM-SLIT with dynamic maintenance dose ascending regimen offers an "optimal" treatment for AR patients while maintaining safety. This study introduced a pattern for individualized dose adjustment in clinical practice, offering potential benefits for AR patients.

20.
J Allergy Clin Immunol ; 151(4): 991-1004.e20, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37032586

RESUMEN

BACKGROUND: Glucose concentrations are increased in nasal secretions in chronic rhinosinusitis (CRS). However, the glucose metabolism and its contribution to disease pathogenesis in CRS remain unexplored. OBJECTIVES: We sought to explore the glucose metabolism and its effect on the function of nasal epithelial cells in CRS with and without nasal polyps (CRSwNP and CRSsNP). METHODS: Glucose metabolites were detected with mass spectrometry. The mRNA levels of glucose transporters (GLUTs), metabolic enzymes, and inflammatory mediators were detected by quantitative RT-PCR. The protein expression of GLUTs was studied by immunofluorescence staining, Western blotting, and flow cytometry. Glucose uptake was measured by using fluorescent glucose analog. Human nasal epithelial cells (HNECs) were cultured. Bioenergetic analysis was performed with Seahorse XF analyzer. Gene expression in HNECs was profiled by RNA sequencing. RESULTS: Increased glucose concentrations in nasal secretions was confirmed in both CRSsNP and CRSwNP. GLUT4, GLUT10, and GLUT11 were abundantly expressed in HNECs, whose expression was upregulated by inflammatory cytokines and D-glucose and was increased in CRS. Glucose uptake, glycolysis and tricarboxylic acid cycle metabolites, metabolic enzymes, and extracellular acidification rate and oxygen consumption rates were increased in HNECs in CRSsNP and CRSwNP, with a predominant shift to glycolysis. HNECs treated with high-level apical D-glucose showed enhanced glucose uptake, predominant glycolysis, and upregulated production of IL-1α, IL-1ß, TNF-α, CCL20, and CXCL8, which was suppressed by 2-deoxy-D-glucose, an inhibitor of glycolysis. CONCLUSIONS: Increased glucose in nasal secretions promotes glucose uptake and predominant glycolysis in epithelial cells, augmenting the proinflammatory function of epithelial cells in CRS.


Asunto(s)
Pólipos Nasales , Rinitis , Sinusitis , Humanos , Rinitis/metabolismo , Células Cultivadas , Nariz , Citocinas/metabolismo , Pólipos Nasales/metabolismo , Sinusitis/metabolismo , Células Epiteliales/metabolismo , Enfermedad Crónica , Mucosa Nasal/metabolismo
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