RESUMEN
Purine nucleotides are vital for RNA and DNA synthesis, signaling, metabolism, and energy homeostasis. To synthesize purines, cells use two principal routes: the de novo and salvage pathways. Traditionally, it is believed that proliferating cells predominantly rely on de novo synthesis, whereas differentiated tissues favor the salvage pathway. Unexpectedly, we find that adenine and inosine are the most effective circulating precursors for supplying purine nucleotides to tissues and tumors, while hypoxanthine is rapidly catabolized and poorly salvaged in vivo. Quantitative metabolic analysis demonstrates comparative contribution from de novo synthesis and salvage pathways in maintaining purine nucleotide pools in tumors. Notably, feeding mice nucleotides accelerates tumor growth, while inhibiting purine salvage slows down tumor progression, revealing a crucial role of the salvage pathway in tumor metabolism. These findings provide fundamental insights into how normal tissues and tumors maintain purine nucleotides and highlight the significance of purine salvage in cancer.
Asunto(s)
Neoplasias , Nucleótidos de Purina , Purinas , Animales , Ratones , Purinas/metabolismo , Purinas/biosíntesis , Neoplasias/metabolismo , Neoplasias/patología , Nucleótidos de Purina/metabolismo , Humanos , Inosina/metabolismo , Hipoxantina/metabolismo , Ratones Endogámicos C57BL , Adenina/metabolismo , Línea Celular Tumoral , FemeninoRESUMEN
Metabolic anomalies contribute to tissue dysfunction. Current metabolism research spans from organelles to populations, and new technologies can accommodate investigation across these scales. Here, we review recent advancements in metabolic analysis, including small-scale metabolomics techniques amenable to organelles and rare cell types, functional screening to explore how cells respond to metabolic stress, and imaging approaches to non-invasively assess metabolic perturbations in diseases. We discuss how metabolomics provides an informative phenotypic dimension that complements genomic analysis in Mendelian and non-Mendelian disorders. We also outline pressing challenges and how addressing them may further clarify the biochemical basis of human disease.
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Genómica , Metabolómica , Diagnóstico por Imagen , Humanos , Metabolómica/métodosRESUMEN
Schistosomes cause morbidity and death throughout the developing world due to the massive numbers of eggs female worms deposit into the blood of their host. Studies dating back to the 1920s show that female schistosomes rely on constant physical contact with a male worm both to become and remain sexually mature; however, the molecular details governing this process remain elusive. Here, we uncover a nonribosomal peptide synthetase that is induced in male worms upon pairing with a female and find that it is essential for the ability of male worms to stimulate female development. We demonstrate that this enzyme generates ß-alanyl-tryptamine that is released by paired male worms. Furthermore, synthetic ß-alanyl-tryptamine can replace male worms to stimulate female sexual development and egg laying. These data reveal that peptide-based pheromone signaling controls female schistosome sexual maturation, suggesting avenues for therapeutic intervention and uncovering a role for nonribosomal peptides as metazoan signaling molecules.
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Péptidos , Feromonas , Schistosoma/crecimiento & desarrollo , Animales , Femenino , Masculino , Biosíntesis de Péptidos Independientes de Ácidos Nucleicos , TriptaminasRESUMEN
Diversity in the genetic lesions that cause cancer is extreme. In consequence, a pressing challenge is the development of drugs that target patient-specific disease mechanisms. To address this challenge, we employed a chemistry-first discovery paradigm for de novo identification of druggable targets linked to robust patient selection hypotheses. In particular, a 200,000 compound diversity-oriented chemical library was profiled across a heavily annotated test-bed of >100 cellular models representative of the diverse and characteristic somatic lesions for lung cancer. This approach led to the delineation of 171 chemical-genetic associations, shedding light on the targetability of mechanistic vulnerabilities corresponding to a range of oncogenotypes present in patient populations lacking effective therapy. Chemically addressable addictions to ciliogenesis in TTC21B mutants and GLUT8-dependent serine biosynthesis in KRAS/KEAP1 double mutants are prominent examples. These observations indicate a wealth of actionable opportunities within the complex molecular etiology of cancer.
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Carcinoma de Pulmón de Células no Pequeñas/patología , Proliferación Celular/efectos de los fármacos , Neoplasias Pulmonares/patología , Bibliotecas de Moléculas Pequeñas/farmacología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Línea Celular Tumoral , Familia 4 del Citocromo P450/deficiencia , Familia 4 del Citocromo P450/genética , Descubrimiento de Drogas , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Glucocorticoides/farmacología , Proteínas Facilitadoras del Transporte de la Glucosa/antagonistas & inhibidores , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/genética , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Mutación , Factor 2 Relacionado con NF-E2/antagonistas & inhibidores , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Receptor Notch2/genética , Receptor Notch2/metabolismo , Receptores de Glucocorticoides/antagonistas & inhibidores , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/metabolismoRESUMEN
Transformed cells adapt metabolism to support tumor initiation and progression. Specific metabolic activities can participate directly in the process of transformation or support the biological processes that enable tumor growth. Exploiting cancer metabolism for clinical benefit requires defining the pathways that are limiting for cancer progression and understanding the context specificity of metabolic preferences and liabilities in malignant cells. Progress toward answering these questions is providing new insight into cancer biology and can guide the more effective targeting of metabolism to help patients.
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Redes y Vías Metabólicas , Neoplasias/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Proliferación Celular , Transformación Celular Neoplásica , Ciclo del Ácido Cítrico , Humanos , NADP/metabolismo , Neoplasias/patología , Nucleótidos/biosíntesisRESUMEN
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.
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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/metabolismoRESUMEN
Non-small cell lung cancer (NSCLC) is heterogeneous in the genetic and environmental parameters that influence cell metabolism in culture. Here, we assessed the impact of these factors on human NSCLC metabolism in vivo using intraoperative (13)C-glucose infusions in nine NSCLC patients to compare metabolism between tumors and benign lung. While enhanced glycolysis and glucose oxidation were common among these tumors, we observed evidence for oxidation of multiple nutrients in each of them, including lactate as a potential carbon source. Moreover, metabolically heterogeneous regions were identified within and between tumors, and surprisingly, our data suggested potential contributions of non-glucose nutrients in well-perfused tumor areas. Our findings not only demonstrate the heterogeneity in tumor metabolism in vivo but also highlight the strong influence of the microenvironment on this feature.
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Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Microambiente Tumoral , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/irrigación sanguínea , Ciclo del Ácido Cítrico , Femenino , Glucólisis , Humanos , Neoplasias Pulmonares/irrigación sanguínea , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía de Emisión de PositronesRESUMEN
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.
RESUMEN
Glioblastomas and brain metastases are highly proliferative brain tumors with short survival times. Previously, using (13)C-NMR analysis of brain tumors resected from patients during infusion of (13)C-glucose, we demonstrated that there is robust oxidation of glucose in the citric acid cycle, yet glucose contributes less than 50% of the carbons to the acetyl-CoA pool. Here, we show that primary and metastatic mouse orthotopic brain tumors have the capacity to oxidize [1,2-(13)C]acetate and can do so while simultaneously oxidizing [1,6-(13)C]glucose. The tumors do not oxidize [U-(13)C]glutamine. In vivo oxidation of [1,2-(13)C]acetate was validated in brain tumor patients and was correlated with expression of acetyl-CoA synthetase enzyme 2, ACSS2. Together, the data demonstrate a strikingly common metabolic phenotype in diverse brain tumors that includes the ability to oxidize acetate in the citric acid cycle. This adaptation may be important for meeting the high biosynthetic and bioenergetic demands of malignant growth.
Asunto(s)
Acetato CoA Ligasa/metabolismo , Acetatos/metabolismo , Neoplasias Encefálicas/metabolismo , Ciclo del Ácido Cítrico , Glioblastoma/metabolismo , Acetato CoA Ligasa/genética , Animales , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/secundario , Modelos Animales de Enfermedad , Glioblastoma/patología , Ácido Glutámico/metabolismo , Humanos , Ratones , Metástasis de la Neoplasia/patologíaRESUMEN
Naive CD8+ T cells differentiating into effector T cells increase glucose uptake and shift from quiescent to anabolic metabolism. Although much is known about the metabolism of cultured T cells, how T cells use nutrients during immune responses in vivo is less well defined. Here, we combined bioenergetic profiling and 13C-glucose infusion techniques to investigate the metabolism of CD8+ T cells responding to Listeria infection. In contrast to in vitro-activated T cells, which display hallmarks of Warburg metabolism, physiologically activated CD8+ T cells displayed greater rates of oxidative metabolism, higher bioenergetic capacity, differential use of pyruvate, and prominent flow of 13C-glucose carbon to anabolic pathways, including nucleotide and serine biosynthesis. Glucose-dependent serine biosynthesis mediated by the enzyme Phgdh was essential for CD8+ T cell expansion in vivo. Our data highlight fundamental differences in glucose use by pathogen-specific T cells in vivo, illustrating the impact of environment on T cell metabolic phenotypes.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Metabolismo Energético , Glucosa/metabolismo , Activación de Linfocitos/inmunología , Metaboloma , Metabolómica , Animales , Proliferación Celular , Cromatografía de Gases y Espectrometría de Masas , Glucólisis , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Activación de Linfocitos/genética , Metabolómica/métodos , Ratones , Estrés Oxidativo , Virosis/genética , Virosis/inmunología , Virosis/metabolismo , Virosis/virologíaRESUMEN
Context-specific molecular vulnerabilities that arise during tumor evolution represent an attractive intervention target class. However, the frequency and diversity of somatic lesions detected among lung tumors can confound efforts to identify these targets. To confront this challenge, we have applied parallel screening of chemical and genetic perturbations within a panel of molecularly annotated NSCLC lines to identify intervention opportunities tightly linked to molecular response indicators predictive of target sensitivity. Anchoring this analysis on a matched tumor/normal cell model from a lung adenocarcinoma patient identified three distinct target/response-indicator pairings that are represented with significant frequencies (6%-16%) in the patient population. These include NLRP3 mutation/inflammasome activation-dependent FLIP addiction, co-occurring KRAS and LKB1 mutation-driven COPI addiction, and selective sensitivity to a synthetic indolotriazine that is specified by a seven-gene expression signature. Target efficacies were validated in vivo, and mechanism-of-action studies informed generalizable principles underpinning cancer cell biology.
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Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Indoles/farmacología , Neoplasias Pulmonares/metabolismo , Triazinas/farmacología , Animales , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Proteínas Portadoras , Línea Celular Tumoral , Proteína Coatómero/metabolismo , Femenino , Genes ras , Xenoinjertos , Humanos , Neoplasias Pulmonares/patología , Lisosomas/metabolismo , Ratones , Terapia Molecular Dirigida , Proteína con Dominio Pirina 3 de la Familia NLR , Trasplante de Neoplasias , Fosforilación OxidativaRESUMEN
Vessel sprouting by migrating tip and proliferating stalk endothelial cells (ECs) is controlled by genetic signals (such as Notch), but it is unknown whether metabolism also regulates this process. Here, we show that ECs relied on glycolysis rather than on oxidative phosphorylation for ATP production and that loss of the glycolytic activator PFKFB3 in ECs impaired vessel formation. Mechanistically, PFKFB3 not only regulated EC proliferation but also controlled the formation of filopodia/lamellipodia and directional migration, in part by compartmentalizing with F-actin in motile protrusions. Mosaic in vitro and in vivo sprouting assays further revealed that PFKFB3 overexpression overruled the pro-stalk activity of Notch, whereas PFKFB3 deficiency impaired tip cell formation upon Notch blockade, implying that glycolysis regulates vessel branching.
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Células Endoteliales/metabolismo , Glucólisis , Neovascularización Fisiológica , Fosfofructoquinasa-2/metabolismo , Animales , Línea Celular Tumoral , Células Cultivadas , Células Endoteliales/citología , Femenino , Eliminación de Gen , Silenciador del Gen , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Fosfofructoquinasa-2/genética , Seudópodos/metabolismo , Pez CebraRESUMEN
Two forms of associative learning-delay conditioning and trace conditioning-have been widely investigated in humans and higher-order mammals1. In delay conditioning, an unconditioned stimulus (for example, an electric shock) is introduced in the final moments of a conditioned stimulus (for example, a tone), with both ending at the same time. In trace conditioning, a 'trace' interval separates the conditioned stimulus and the unconditioned stimulus. Trace conditioning therefore relies on maintaining a neural representation of the conditioned stimulus after its termination (hence making distraction possible2), to learn the conditioned stimulus-unconditioned stimulus contingency3; this makes it more cognitively demanding than delay conditioning4. Here, by combining virtual-reality behaviour with neurogenetic manipulations and in vivo two-photon brain imaging, we show that visual trace conditioning and delay conditioning in Drosophila mobilize R2 and R4m ring neurons in the ellipsoid body. In trace conditioning, calcium transients during the trace interval show increased oscillations and slower declines over repeated training, and both of these effects are sensitive to distractions. Dopaminergic activity accompanies signal persistence in ring neurons, and this is decreased by distractions solely during trace conditioning. Finally, dopamine D1-like and D2-like receptor signalling in ring neurons have different roles in delay and trace conditioning; dopamine D1-like receptor 1 mediates both forms of conditioning, whereas the dopamine D2-like receptor is involved exclusively in sustaining ring neuron activity during the trace interval of trace conditioning. These observations are similar to those previously reported in mammals during arousal5, prefrontal activation6 and high-level cognitive learning7,8.
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Condicionamiento Clásico , Drosophila , Animales , Encéfalo/citología , Encéfalo/fisiología , Condicionamiento Clásico/fisiología , Dopamina , Drosophila/anatomía & histología , Drosophila/citología , Drosophila/fisiología , Neuronas , Receptores DopaminérgicosRESUMEN
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.
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Ciclo del Ácido Cítrico , Desarrollo Fetal , Metabolómica , Placenta , Animales , Embrión de Mamíferos/metabolismo , Femenino , Glucosa/metabolismo , Mamíferos/metabolismo , Ratones , Placenta/metabolismo , EmbarazoRESUMEN
Obtaining a burning plasma is a critical step towards self-sustaining fusion energy1. A burning plasma is one in which the fusion reactions themselves are the primary source of heating in the plasma, which is necessary to sustain and propagate the burn, enabling high energy gain. After decades of fusion research, here we achieve a burning-plasma state in the laboratory. These experiments were conducted at the US National Ignition Facility, a laser facility delivering up to 1.9 megajoules of energy in pulses with peak powers up to 500 terawatts. We use the lasers to generate X-rays in a radiation cavity to indirectly drive a fuel-containing capsule via the X-ray ablation pressure, which results in the implosion process compressing and heating the fuel via mechanical work. The burning-plasma state was created using a strategy to increase the spatial scale of the capsule2,3 through two different implosion concepts4-7. These experiments show fusion self-heating in excess of the mechanical work injected into the implosions, satisfying several burning-plasma metrics3,8. Additionally, we describe a subset of experiments that appear to have crossed the static self-heating boundary, where fusion heating surpasses the energy losses from radiation and conduction. These results provide an opportunity to study α-particle-dominated plasmas and burning-plasma physics in the laboratory.
RESUMEN
An understanding of metabolic pathways based solely on biochemistry textbooks would underestimate the pervasive role of metabolism in essentially every aspect of biology. It is evident from recent work that many human diseases involve abnormal metabolic states--often genetically programmed--that perturb normal physiology and lead to severe tissue dysfunction. Understanding these metabolic outliers is now a crucial frontier in disease-oriented research. This Review discusses the broad impact of metabolism in cellular function and how modern concepts of metabolism can inform our understanding of common diseases like cancer and also considers the prospects of developing new metabolic approaches to disease treatment.
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Redes y Vías Metabólicas , Animales , Humanos , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/patología , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patologíaRESUMEN
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.
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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/metabolismoRESUMEN
Tumors display increased uptake and processing of nutrients to fulfill the demands of rapidly proliferating cancer cells. Seminal studies have shown that the proto-oncogene MYC promotes metabolic reprogramming by altering glutamine uptake and metabolism in cancer cells. How MYC regulates the metabolism of other amino acids in cancer is not fully understood. Using high-performance liquid chromatography (HPLC)-tandem mass spectrometry (LC-MS/MS), we found that MYC increased intracellular levels of tryptophan and tryptophan metabolites in the kynurenine pathway. MYC induced the expression of the tryptophan transporters SLC7A5 and SLC1A5 and the enzyme arylformamidase (AFMID), involved in the conversion of tryptophan into kynurenine. SLC7A5, SLC1A5, and AFMID were elevated in colon cancer cells and tissues, and kynurenine was significantly greater in tumor samples than in the respective adjacent normal tissue from patients with colon cancer. Compared with normal human colonic epithelial cells, colon cancer cells were more sensitive to the depletion of tryptophan. Blocking enzymes in the kynurenine pathway caused preferential death of established colon cancer cells and transformed colonic organoids. We found that only kynurenine and no other tryptophan metabolite promotes the nuclear translocation of the transcription factor aryl hydrocarbon receptor (AHR). Blocking the interaction between AHR and kynurenine with CH223191 reduced the proliferation of colon cancer cells. Therefore, we propose that limiting cellular kynurenine or its downstream targets could present a new strategy to reduce the proliferation of MYC-dependent cancer cells.
Asunto(s)
Neoplasias del Colon/fisiopatología , Quinurenina/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Triptófano/metabolismo , Sistema de Transporte de Aminoácidos ASC/genética , Antineoplásicos/farmacología , Arilformamidasa/genética , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Humanos , Indoles/farmacología , Quinurenina/genética , Transportador de Aminoácidos Neutros Grandes 1/genética , Antígenos de Histocompatibilidad Menor/genética , Oximas/farmacología , Proto-Oncogenes Mas , Sulfonamidas/farmacologíaRESUMEN
The mechanics of the cellular microenvironment continuously modulates cell functions such as growth, survival, apoptosis, differentiation and morphogenesis via cytoskeletal remodelling and actomyosin contractility1-3. Although all of these processes consume energy4,5, it is unknown whether and how cells adapt their metabolic activity to variable mechanical cues. Here we report that the transfer of human bronchial epithelial cells from stiff to soft substrates causes a downregulation of glycolysis via proteasomal degradation of the rate-limiting metabolic enzyme phosphofructokinase (PFK). PFK degradation is triggered by the disassembly of stress fibres, which releases the PFK-targeting E3 ubiquitin ligase tripartite motif (TRIM)-containing protein 21 (TRIM21). Transformed non-small-cell lung cancer cells, which maintain high glycolytic rates regardless of changing environmental mechanics, retain PFK expression by downregulating TRIM21, and by sequestering residual TRIM21 on a stress-fibre subset that is insensitive to substrate stiffness. Our data reveal a mechanism by which glycolysis responds to architectural features of the actomyosin cytoskeleton, thus coupling cell metabolism to the mechanical properties of the surrounding tissue. These processes enable normal cells to tune energy production in variable microenvironments, whereas the resistance of the cytoskeleton in response to mechanical cues enables the persistence of high glycolytic rates in cancer cells despite constant alterations of the tumour tissue.
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Microambiente Celular , Citoesqueleto/metabolismo , Células Epiteliales/citología , Células Epiteliales/metabolismo , Glucosa/metabolismo , Glucólisis , Dureza , Actinas/metabolismo , Actomiosina/metabolismo , Animales , Bronquios/citología , Bovinos , Diferenciación Celular , Línea Celular , Humanos , Neoplasias/metabolismo , Neoplasias/patología , Fosfofructoquinasas/química , Fosfofructoquinasas/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Ribonucleoproteínas/metabolismo , Fibras de Estrés/metabolismo , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
Metastasis requires cancer cells to undergo metabolic changes that are poorly understood1-3. Here we show that metabolic differences among melanoma cells confer differences in metastatic potential as a result of differences in the function of the MCT1 transporter. In vivo isotope tracing analysis in patient-derived xenografts revealed differences in nutrient handling between efficiently and inefficiently metastasizing melanomas, with circulating lactate being a more prominent source of tumour lactate in efficient metastasizers. Efficient metastasizers had higher levels of MCT1, and inhibition of MCT1 reduced lactate uptake. MCT1 inhibition had little effect on the growth of primary subcutaneous tumours, but resulted in depletion of circulating melanoma cells and reduced the metastatic disease burden in patient-derived xenografts and in mouse melanomas. In addition, inhibition of MCT1 suppressed the oxidative pentose phosphate pathway and increased levels of reactive oxygen species. Antioxidants blocked the effects of MCT1 inhibition on metastasis. MCT1high and MCT1-/low cells from the same melanomas had similar capacities to form subcutaneous tumours, but MCT1high cells formed more metastases after intravenous injection. Metabolic differences among cancer cells thus confer differences in metastatic potential as metastasizing cells depend on MCT1 to manage oxidative stress.