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1.
Acta Neuropathol Commun ; 9(1): 16, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33468252

RESUMEN

Cancer cells optimize nutrient utilization to supply energetic and biosynthetic pathways. This metabolic process also includes redox maintenance and epigenetic regulation through nucleic acid and protein methylation, which enhance tumorigenicity and clinical resistance. However, less is known about how cancer cells exhibit metabolic flexibility to sustain cell growth and survival from nutrient starvation. Here, we find that serine and glycine levels were higher in low-nutrient regions of tumors in glioblastoma multiforme (GBM) patients than they were in other regions. Metabolic and functional studies in GBM cells demonstrated that serine availability and one-carbon metabolism support glioma cell survival following glutamine deprivation. Serine synthesis was mediated through autophagy rather than glycolysis. Gene expression analysis identified upregulation of methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) to regulate one-carbon metabolism. In clinical samples, MTHFD2 expression was highest in the nutrient-poor areas around "pseudopalisading necrosis." Genetic suppression of MTHFD2 and autophagy inhibition caused tumor cell death and growth inhibition of glioma cells upon glutamine deprivation. These results highlight a critical role for serine-dependent one-carbon metabolism in surviving glutamine starvation and suggest new therapeutic targets for glioma cells adapting to a low-nutrient microenvironment.


Asunto(s)
Aminohidrolasas/genética , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Glutamina/metabolismo , Glicina/metabolismo , Metilenotetrahidrofolato Deshidrogenasa (NADP)/genética , Enzimas Multifuncionales/genética , Serina/metabolismo , Aminohidrolasas/metabolismo , Autofagia/genética , Línea Celular Tumoral , Proliferación Celular/genética , Supervivencia Celular , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Espectroscopía de Resonancia Magnética , Metabolómica , Metilenotetrahidrofolato Deshidrogenasa (NADP)/metabolismo , Enzimas Multifuncionales/metabolismo , Microambiente Tumoral/genética , Regulación hacia Arriba
2.
Diagn Pathol ; 11: 3, 2016 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-26755204

RESUMEN

A 55-year-old postmenopausal female presented with genital bleeding and lower abdominal mass. An abdominal MRI revealed a heterogeneously enhanced, 15 × 10 cm mass, completely filling the lumen of the enlarged uterus. The cytologic analysis of the mass showed tumor cells in small clusters and as individual cells showing hyperchromatic round to oval nuclei, and pleomorphic and occasionally unipolar "tadpole"-shaped cytoplasm, in a background of severe necrosis and many degenerated squamous cells. We first interpreted it merely as atypical cells, possibly originated from sarcoma. A total abdominal hysterectomy and salpingo-oophorectomy were performed, and gross examination showed an exophytic polypoid mass with a whitish to white-grayish, necrotic appearance, protruding from the endometrial mucosa. Microscopically, the tumor was composed of a diffuse proliferation of highly atypical spindle-shaped cells, admixed with many characteristic rhabdomyoblasts having abundant densely eosinophilic cytoplasm with sometimes distinct cross-striations, coexisted with cellular primitive small blue round to oval cells foci. However, neither carcinoma nor additional heterologous sarcoma components were completely seen within our thorough investigation. Therefore, we finally made a diagnosis of embryonal rhabdomyosarcoma arising from the uterine corpus. We should be aware that owing to its characteristic features, cytopathologists might be able to determine a genuine diagnosis, based on multiple and adequate cytology samplings.


Asunto(s)
Posmenopausia , Rabdomiosarcoma Embrionario/patología , Neoplasias Uterinas/patología , Biomarcadores de Tumor/análisis , Biopsia , Diagnóstico Diferencial , Femenino , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Rabdomiosarcoma Embrionario/química , Rabdomiosarcoma Embrionario/cirugía , Resultado del Tratamiento , Carga Tumoral , Neoplasias Uterinas/química , Neoplasias Uterinas/cirugía
3.
J Clin Invest ; 125(4): 1591-602, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25798620

RESUMEN

The mechanistic target of rapamycin (mTOR) is hyperactivated in many types of cancer, rendering it a compelling drug target; however, the impact of mTOR inhibition on metabolic reprogramming in cancer is incompletely understood. Here, by integrating metabolic and functional studies in glioblastoma multiforme (GBM) cell lines, preclinical models, and clinical samples, we demonstrate that the compensatory upregulation of glutamine metabolism promotes resistance to mTOR kinase inhibitors. Metabolomic studies in GBM cells revealed that glutaminase (GLS) and glutamate levels are elevated following mTOR kinase inhibitor treatment. Moreover, these mTOR inhibitor-dependent metabolic alterations were confirmed in a GBM xenograft model. Expression of GLS following mTOR inhibitor treatment promoted GBM survival in an α-ketoglutarate-dependent (αKG-dependent) manner. Combined genetic and/or pharmacological inhibition of mTOR kinase and GLS resulted in massive synergistic tumor cell death and growth inhibition in tumor-bearing mice. These results highlight a critical role for compensatory glutamine metabolism in promoting mTOR inhibitor resistance and suggest that rational combination therapy has the potential to suppress resistance.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Benzofenantridinas/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Resistencia a Antineoplásicos/fisiología , Glioblastoma/tratamiento farmacológico , Glutaminasa/fisiología , Glutamina/metabolismo , Indoles/farmacología , Terapia Molecular Dirigida , Proteínas de Neoplasias/fisiología , Inhibidores de Proteínas Quinasas/farmacología , Purinas/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Anciano , Animales , Benzofenantridinas/administración & dosificación , Benzofenantridinas/farmacología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Ciclo del Ácido Cítrico , Sinergismo Farmacológico , Metabolismo Energético , Cromatografía de Gases y Espectrometría de Masas , Glioblastoma/metabolismo , Glioblastoma/patología , Ácido Glutámico/metabolismo , Glutaminasa/antagonistas & inhibidores , Glutaminasa/biosíntesis , Glutaminasa/genética , Glucólisis , Humanos , Indoles/administración & dosificación , Indoles/uso terapéutico , Ácidos Cetoglutáricos/metabolismo , Espectroscopía de Resonancia Magnética , Masculino , Metaboloma/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Inhibidores de Proteínas Quinasas/uso terapéutico , Purinas/administración & dosificación , Purinas/uso terapéutico , ARN Interferente Pequeño/farmacología , Prueba de Desempeño de Rotación con Aceleración Constante , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Lóbulo Temporal/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Diagn Pathol ; 7: 143, 2012 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-23075171

RESUMEN

A 67-year-old Japanese female was followed up due to prolonged idiopathic thrombocytopenia with non-response to steroid therapy for 4 years, but recent progressive pancytopenia, hypo-albuminemia, and hypo-γ-globulinemia were presented. An abdominal CT scan revealed heterogeneously enhanced splenomegaly without any nodular lesions. A splenectomy was performed, and gross examination showed markedly hyperemic red pulp, weighing 760 g, accompanied by multiple foci of peripheral anemic infarction. Surprisingly, microscopic findings exhibited a diffuse proliferation of medium-sized to large tumor cells having pleomorphic nuclei, prominent nucleoli, and abundant eosinophilic cytoplasm, predominantly within the sinuses and cords of the red pulp, which occasionally displayed conspicuous hemophagocytosis and vascular permeation. In immunohistochemistry, these atypical cells were specifically positive for CD68 (KP-1), CD163, and lysozyme, which was consistent with histiocytic sarcoma (HS) of the spleen. Subsequently, section from the aspiration of bone marrow showed infiltration of the neoplastic cells associated with erythrophagocytosis 2 months after the operation, but never before it. Therefore, primary splenic HS presenting with secondary bone marrow involvement was conclusively diagnosed. Since early diagnosis and treatment are necessary for the HS patients with poor outcomes, splenic HS should be considered as a differential diagnosis in cases with chronic thrombocytopenia and splenomegaly. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1009474924812827.


Asunto(s)
Neoplasias de la Médula Ósea/secundario , Sarcoma Histiocítico/complicaciones , Sarcoma Histiocítico/patología , Neoplasias del Bazo/complicaciones , Neoplasias del Bazo/patología , Esplenomegalia/etiología , Esplenomegalia/patología , Trombocitopenia/etiología , Anciano , Biomarcadores de Tumor/análisis , Neoplasias de la Médula Ósea/química , Femenino , Sarcoma Histiocítico/metabolismo , Sarcoma Histiocítico/cirugía , Humanos , Inmunohistoquímica , Linfohistiocitosis Hemofagocítica/etiología , Valor Predictivo de las Pruebas , Esplenectomía , Neoplasias del Bazo/química , Neoplasias del Bazo/cirugía , Esplenomegalia/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
5.
FEBS Lett ; 586(16): 2318-25, 2012 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-22659183

RESUMEN

Hepatitis C virus core protein (Core) contributes to HCV pathogenicity. Here, we demonstrate that Core impairs growth in budding yeast. We identify HSP90 inhibitors as compounds that reduce intracellular Core protein level and restore yeast growth. Our results suggest that HSC90 (Hsc82) may function in the protection of the nascent Core polypeptide against degradation in yeast and the C-terminal region of Core corresponding to the organelle-interaction domain was responsible for Hsc82-dependent stability. The yeast system may be utilized to select compounds that can direct the C-terminal region to reduce the stability of Core protein.


Asunto(s)
Regulación Viral de la Expresión Génica , Hepacivirus/metabolismo , Saccharomyces cerevisiae/virología , Proteínas del Núcleo Viral/metabolismo , Línea Celular Tumoral/virología , Proteínas Fúngicas/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Péptidos/química , Plásmidos/metabolismo , Conformación Proteica , Estructura Terciaria de Proteína , Factores de Tiempo
6.
Masui ; 59(8): 1013-5, 2010 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-20715530

RESUMEN

Spinal cord injury (SCI) is a rare disease that offers challenges to anesthesiologists, while laparoscopic cholecystectomy (LC) has become common in recent years. We report a case of adult patient with chronic high SCI who underwent LC. A 62-year-old man, a known case of cervical SCI, was presented for LC. Anesthetic problems included circulatory and respiratory complications because of both SCI and pneumoperitoneum. Anesthesia was induced with propofol and a standard endotracheal tube was inserted with vecuronium; and thereafter anesthesia was maintained with small bolus doses of fentanyl and sevoflurane inhalation in the absence of epidural block. The intra- and post-operative course was completely uneventful without any episode of autonomic hyperreflexia. Due to a lack of sensory and motor function, SCI patients will receive little benefit from minimally invasive laparoscopic procedures. In conclusion, compared to open laparotomy, LC will minimize surgical trauma and hospital stay, but may not always minimize complications in anesthetic management. To the best of our knowlegde this is the first report in the literature which describes anesthesia for laparoscopic surgery in a SCI patient.


Asunto(s)
Anestesia por Inhalación , Colecistectomía Laparoscópica , Traumatismos de la Médula Espinal/complicaciones , Humanos , Masculino , Persona de Mediana Edad
7.
Int J Hematol ; 86(5): 451-4, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18192115

RESUMEN

Cord blood transplantation (CBT) is being increasingly performed in adults and is now becoming a standard therapeutic alternative to bone marrow transplantation; however, graft failure is one of the associated problems of CBT in adults. A 44-year-old woman with acute myelogenous leukemia in partial remission received an unrelated CBT. Suspected veno-occlusive disease developed, however, and hemopoietic recovery was delayed. A bone marrow examination on the 27th day revealed empty marrow with a relative increase in macrophages, and the serum ferritin concentration was extremely high. Impending failure of the graft due to a hemophagocytic syndrome-like condition was strongly suspected, although donor cells were dominant according to a fluorescence in situ hybridization analysis. A second CBT was performed on the 30th day after a preparatory regimen of methylprednisolone and low-dose fludarabine (total dose, 90 mg/m2). Unexpectedly, the the first donor's cells recovered on the fourth day after the second CBT; however, the cells to finally engraft were those of the second donor. This case is informative as an example of rescue management for suspected graft failure.


Asunto(s)
Trasplante de Células Madre de Sangre del Cordón Umbilical , Funcionamiento Retardado del Injerto/terapia , Supervivencia de Injerto , Leucemia Mieloide Aguda/terapia , Donantes de Tejidos , Acondicionamiento Pretrasplante , Adulto , Antiinflamatorios/administración & dosificación , Médula Ósea/metabolismo , Médula Ósea/patología , Funcionamiento Retardado del Injerto/sangre , Funcionamiento Retardado del Injerto/patología , Selección de Donante , Femenino , Ferritinas/sangre , Hematopoyesis , Humanos , Leucemia Mieloide Aguda/sangre , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/patología , Macrófagos/metabolismo , Macrófagos/patología , Metilprednisolona/administración & dosificación , Agonistas Mieloablativos/administración & dosificación , Enfermedades Vasculares/sangre , Enfermedades Vasculares/etiología , Enfermedades Vasculares/patología , Enfermedades Vasculares/terapia , Vidarabina/administración & dosificación , Vidarabina/análogos & derivados
9.
Med Oncol ; 20(4): 335-48, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14716029

RESUMEN

The present study was designed for identifying the protein synthesis in cytoplasm of dendritic cells transfected with in vitro transcribed mRNA and cellular total RNA extracted from tumor cells. Dendritic cells were generated from cord blood-CD34+ cells by culture with GM-CSF, SCF, and TNF-alpha, or from peripheral blood adherent cells or CD14+ cells by culture with GM-CSF and IL-4. Dendritic cells were transfected with in vitro transcribed EGFP mRNA or cellular total RNA, which was isolated from EGFP expressing K562, by electroporation using a square-wave pulse. Optimal in vitro transcribed EGFP mRNA transfection efficiency (>90%) was observed in a single electroporation of 1.75 kV/cm (electric field strength) with a pulse width of 250 micros. Although the intensity of EGFP expression in dendritic cells transfected with cellular total RNA was less compared with that in dendritic cells transfected with in vitro transcribed EGFP mRNA, a definite cytoplasmic synthesis of EGFP was demonstrated in dendritic cells transfected with cellular total RNA. The visual identification of cytoplasmic expression of cellular total RNA in dendritic cells revealed that electroporation of tumor cell-derived RNA could be a useful tool to load dendritic cells with tumor antigens for establishing an efficient dendritic cell-based tumor immunotherapy.


Asunto(s)
Células Dendríticas/metabolismo , Proteínas Luminiscentes/metabolismo , ARN Mensajero/genética , Transfección/métodos , Células Tumorales Cultivadas/metabolismo , Células Dendríticas/inmunología , Electroporación/métodos , Proteínas Fluorescentes Verdes , Humanos , Inmunoterapia/métodos , ARN Mensajero/aislamiento & purificación
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