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El trauma facial presenta características importantes que repercuten en el diagnóstico y tratamiento de niños y adolescentes. Objetivo: Analizar el cuadro epidemiológico del trauma facial en niños y adolescentes en un hospital de la región sur de Brasil. Materiales e métodos: Se realizó un estudio de corte transversal analítico entre los años de 2000 hasta 2010 en el Hospital São Vicente de Paulo, Passo Fundo, Brasil. Identificando los agentes etiológicos, género, fracturas faciales y la existencia de injurias corporales asociadas a los traumatismos faciales. Resultados: Los traumatismos faciales fueron más frecuentes en el grupo de adolescentes (75.6%) en comparación con la población pediátrica (24.3%). La mandíbula fue el hueso más afectado (33.5%). El traumatismo craneano fue la lesión asociada más frecuente en la población pediátrica (33%). Conclusión: Los hombres presentan mayor prevalencia de trauma facial, siendo que los adolescentes tienden a ser más afectados.
O trauma facial apresenta características importantes que refletem no diagnóstico e tratamento de crianças e adolescentes. Objetivo: Analisar o quadro epidemiológico do trauma facial em crianças e adolescentes em um hospital da região sul do Brasil. Materiais e métodos: Realizou-se um estudo de coorte transversal analítico entre os anos 2000 e 2010, no Hospital São Vicente de Paulo, Passo Fundo, Brasil. Foram identificados os agentes etiológicos, gênero, fraturas faciais e a presença de lesões associadas aos traumatismos faciais. Resultados: Os traumatismos faciais foram mais frequentes no grupo de adolescentes (75.6%), comparado com a população pediátrica (24.3%). A mandíbula foi o osso mais acometido (33.5%). O traumatismo craniano foi a lesão associada mais frequente na população pediátrica (33%). Conclusão: Os homens apresentaram maior prevalência do trauma facial, sendo o grupo de adolescentes o mais acometido.
Facial trauma has major characteristics that affect the diagnosis and treatment of children and adolescents. Objective: To analyze the epidemiology of facial trauma in children and adolescents in a hospital in the south of Brazil. Materials and methods: An analytical crosssectional cohort study was conducted between 2000 and 2010 at Hospital Sao Vicente de Paulo, Passo Fundo, Brazil. Various factors were identified: etiological agents, gender, facial fractures and the existence of body injuries associated with facial trauma. Results: Facial injuries were more common than in the adolescent group (75.6%) compared to the pediatric population (24.3%). The jaw was the most affected bone (33.5%). Cranial trauma was the most common associated lesion in the pediatric population (33%). Conclusion: Men have a higher prevalence of facial trauma and adolescents tend to be more affected.
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Humanos , Niño , Adolescente , Niño , Adolescente , Traumatismos Faciales , Brasil , Huesos FacialesRESUMEN
Introdução: A reconstrução óssea de defeitos craniofaciais é um processo desafiador. Diferentes técnicas operatórias e materiais reconstrutores são utilizados para reestabelecer a forma ideal do crânio. Materiais aloplásticos vem ganhando popularidade nas reconstruções orbitárias devido à sua facilidade de uso, com grande variedade de formas e tamanhos disponíveis. O objetivo deste estudo foi avaliar as reconstruções dos defeitos ósseos orbitários após traumatismos craniofaciais. Metodologia: Trata-se de um estudo observacional, que avaliou pacientes vítimas de traumatismo crânioencefálico com envolvimento orbitário e necessidade de reconstrução por meio de material aloplástico de titânio, atendidos no período de março de 2015 a junho de 2016, no Hospital da Cidade de Passo Fundo, Rio Grande do Sul,Brasil.Resultados: 13 pacientes foram incluídos no estudo e analisados de acordo com idade, gênero, etiologia do trauma,tipos de fratura que envolveram os defeitos craniofaciais e o material utilizado na reconstrução. O exame clínico avaliou a estabilidade da reconstrução, o resultado estético e funcional e a ocorrência de infecção pós-operatória. Tomografias Fan-Beam foram tomadas no pré e pós-operatório. Conclusões:Os resultados obtidos mostram que a escolha do material aloplástico de titânio é segura, e oferece excelente taxa de sucesso estético e funcional, corroborando com a literatura existente... (AU)
Introduction: Bone reconstruction of craniofacial defects is a challenging process. Different surgical techniques and reconstructing materials are used to reestablish the ideal shape of the skull. Alloplastic materials have been gaining popularity in orbital reconstructions due to their ease of use, with a wide variety of shapes and sizes available. The aim of this study was to evaluate the reconstruction of orbital bone defects after craniofacial trauma. Methodology: This is an observational study that evaluated patients who were victims of traumatic brain injury with orbital involvement and the need for reconstruction by means of titanium alloplastic material, treated from March 2015 to June 2016, at the Hospital da Cidade de Passo Fundo, Rio Grande do Sul, Brazil. Results: 13 patients were included in the study and analyzed according to age, gender, trauma etiology, types of fracture involving craniofacial defects and the material used in reconstruction. The clinical examination evaluated the stability of the reconstruction, the aesthetic and functional result and the occurrence of postoperative infection. Fan-Beam tomography were taken before and after surgery. Conclusions: The results obtained show that the choice of titanium alloplastic material is safe and offers an excellent rate of aesthetic and functional success, corroborating the existing literature... (AU)
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Humanos , Masculino , Femenino , Cráneo , Titanio , Traumatismos Faciales , Reconstrucción Mandibular , Lesiones Traumáticas del Encéfalo , Heridas y Lesiones , Huesos , Tomografía , Fracturas ÓseasRESUMEN
[This corrects the article DOI: 10.3389/fonc.2019.01430.].
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Tumor microenvironment has a high concentration of inorganic phosphate (Pi), which is actually a marker for tumor progression. Regarding Pi another class of transporter has been recently studied, an H+-dependent Pi transporter, that is stimulated at acidic pH in Caco2BBE human intestinal cells. In this study, we characterized the H+-dependent Pi transport in breast cancer cell (MDA-MB-231) and around the cancer tissue. MDA-MB-231 cell line presented higher levels of H+-dependent Pi transport as compared to other breast cell lines, such as MCF-10A, MCF-7 and T47-D. The Pi transport was linear as a function of time and exhibited a Michaelis-Menten kinetic of Kmâ¯=â¯1.387⯱â¯0.1674â¯mM Pi and Vmaxâ¯=â¯198.6⯱â¯10.23 Pi × h-1 × mg protein-1 hence reflecting a low affinity Pi transport. H+-dependent Pi uptake was higher at acidic pH. FCCP, Bafilomycin A1 and SCH28080, which deregulate the intracellular levels of protons, inhibited the H+-dependent Pi transport. No effect on pHi was observed in the absence of inorganic phosphate. PAA, an H+-dependent Pi transport inhibitor, reduced the Pi transport activity, cell proliferation, adhesion, and migration. Arsenate, a structural analog of Pi, inhibited the Pi transport. At high Pi conditions, the H+-dependent Pi transport was five-fold higher than the Na+-dependent Pi transport, thus reflecting a low affinity Pi transport. The occurrence of an H+-dependent Pi transporter in tumor cells may endow them with an alternative path for Pi uptake in situations in which Na+-dependent Pi transport is saturated within the tumor microenvironment, thus regulating the energetically expensive tumor processes.
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Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Microambiente Tumoral , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Cadherinas/genética , Cadherinas/metabolismo , Adhesión Celular , Línea Celular , Proliferación Celular , Regulación hacia Abajo/efectos de los fármacos , Femenino , Humanos , Concentración de Iones de Hidrógeno , Transporte Iónico/efectos de los fármacos , Cinética , Ácido Fosfonoacético/farmacología , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo IIb/genética , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo IIb/metabolismo , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Tumor cells exhibit rewired metabolism. We carried out comparative analyses attempting to investigate whether metabolic reprograming could be measured by isothermal microcalorimetry. Intact metastatic cell lines of tongue cell carcinoma, human and murine melanoma, lung, and breast tumors consistently released more heat than non-metastatic cells or cells displaying lower metastatic potential. In tongue squamous carcinoma cells mitochondrial enriched extract reproduced the heat release pattern of intact cells. Cytochalasin D, an actin filament inhibitor, and suppression of metastasis marker Melanoma associated gene 10 (MAGEA10) decreased heat release. Uncoupling protein 2 was highly expressed in metastatic cells, but not in non-metastatic cells. Carnitine palmitoyl transferase-1 inhibitor, Etomoxir strongly inhibited heat release by metastatic cells, thus linking lipid metabolism to thermogenesis. We propose that heat release may be a quantifiable trait of the metastatic process.
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Inorganic phosphate is one of the most essential nutrients for the maintenance of cell life. Because of its essential role in nutrient supplementation, the study of plasma membrane inorganic phosphate transporters in cancer biology has received much attention in recent years. Several studies suggest that these transporters are up-regulated in tumor cells and thus have been considered to be important promoters of tumor progression. Altered expression levels of inorganic phosphate transporters, such as NaPi-IIb (SLC34A2) and PiT-1 (SLC20A1), have been demonstrated. The purpose of this review article was to gather the relevant experimental records on inorganic phosphate transporters in tumors and to demonstrate the importance of these proteins in clinical applications. In this work, we demonstrate that for decades, the potential use of the inorganic phosphate transporter as an antigen for the diagnosis of tumor subtypes remained unknown. With the advancement in molecular biology techniques, phosphate transporters have been identified as being associated with cancer. In addition to their altered expression in cancer, several studies have demonstrated other functions of inorganic phosphate transporters, such as transceptors, rearrangements with oncogenes and modifications in the expression of ABC transporters, aiding in the process of proliferation and drug resistance.
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Neoplasias/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Animales , HumanosRESUMEN
Metastasis of head and neck tumors is responsible for a high mortality rate. Understanding its biochemistry may allow insights into tumorigenesis. To that end we carried out RNA-Seq analyses of 5 SCC9 derived oral cancer cell lines displaying increased invasive potential. Differentially expressed genes (DEGs) were annotated based on p-values and false discovery rate (q-values). All 292 KEGG pathways related to the human genome were compared in order to pinpoint the absolute and relative contributions to the invasive process considering the 8 hallmarks of cancer plus 2 new defined categories, as well as we made with our transcriptomic data. In terms of absolute contribution, the highest correlations were associated to the categories of evading immune destruction and energy metabolism and for relative contributions, angiogenesis and evading immune destruction. DEGs were distributed into each one of all possible modes of regulation, regarding up, down and continuum expression, along the 3 stages of metastatic progression. For p-values twenty-six genes were consistently present along the tumoral progression and 4 for q-values. Among the DEGs, we found 2 novel potentially informative metastatic markers: PIGG and SLC8B1. Furthermore, interactome analysis showed that MYH14, ANGPTL4, PPARD and ENPP1 are amenable to pharmacological interventions.
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Regulación Neoplásica de la Expresión Génica , Evasión Inmune , Neovascularización Patológica/genética , Neoplasias de la Lengua/genética , Transcriptoma , Línea Celular Tumoral , Humanos , Metástasis de la Neoplasia , Neoplasias de la Lengua/inmunología , Neoplasias de la Lengua/patologíaRESUMEN
BACKGROUND: Recent studies demonstrate that interstitial inorganic phosphate is significantly elevated in the breast cancer microenvironment as compared to normal tissue. In addition it has been shown that breast cancer cells express high levels of the NaPi-IIb carrier (SLC34A2), suggesting that this carrier may play a role in breast cancer progression. However, the biochemical behavior of inorganic phosphate (Pi) transporter in this cancer type remains elusive. METHODS: In this work, we characterize the kinetic parameters of Pi transport in the aggressive human breast cancer cell line, MDA-MB-231, and correlated Pi transport with cell migration and adhesion. RESULTS: We determined the influence of sodium concentration, pH, metabolic inhibitors, as well as the affinity for inorganic phosphate in Pi transport. We observed that the inorganic phosphate is dependent on sodium transport (K0,5 value = 21.98 mM for NaCl). Furthermore, the transport is modulated by different pH values and increasing concentrations of Pi, following the Michaelis-Menten kinetics (K0,5 = 0.08 mM Pi). PFA, monensin, furosemide and ouabain inhibited Pi transport, cell migration and adhesion. CONCLUSIONS: Taken together, these results showed that the uptake of Pi in MDA-MB-231 cells is modulated by sodium and by regulatory mechanisms of intracellular sodium gradient. General Significance: Pi transport might be regarded as a potential target for therapy against tumor progression.
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Compuestos Inorgánicos/metabolismo , Fosfatos/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Transporte Biológico , Adhesión Celular , Línea Celular Tumoral , Movimiento Celular , Femenino , Humanos , Cinética , Neoplasias de la Mama Triple Negativas/patologíaRESUMEN
Tumor cells are subjected to a broad range of selective pressures. As a result of the imposed stress, subpopulations of surviving cells exhibit individual biochemical phenotypes that reflect metabolic reprograming. The present work aimed at investigating metabolic parameters of cells displaying increasing degrees of metastatic potential. The metabolites present in cell extracts fraction of tongue fibroblasts and of cell lines derived from human tongue squamous cell carcinoma lineages displaying increasing metastatic potential (SCC9 ZsG, LN1 and LN2) were analyzed by 1H NMR (nuclear magnetic resonance) spectroscopy. Living, intact cells were also examined by the non-invasive method of fluorescence lifetime imaging microscopy (FLIM) based on the auto fluorescence of endogenous NADH. The cell lines reproducibly exhibited distinct metabolic profiles confirmed by Partial Least-Square Discriminant Analysis (PLS-DA) of the spectra. Measurement of endogenous free and bound NAD(P)H relative concentrations in the intact cell lines showed that ZsG and LN1 cells displayed high heterogeneity in the energy metabolism, indicating that the cells would oscillate between glycolysis and oxidative metabolism depending on the microenvironment's composition. However, LN2 cells appeared to have more contributions to the oxidative status, displaying a lower NAD(P)H free/bound ratio. Functional experiments of energy metabolism, mitochondrial physiology, and proliferation assays revealed that all lineages exhibited similar energy features, although resorting to different bioenergetics strategies to face metabolic demands. These differentiated functions may also promote metastasis. We propose that lipid metabolism is related to the increased invasiveness as a result of the accumulation of malonate, methyl malonic acid, n-acetyl and unsaturated fatty acids (CH2)n in parallel with the metastatic potential progression, thus suggesting that the NAD(P)H reflected the lipid catabolic/anabolic pathways.
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Tumor cells display different bioenergetic profiles when compared to normal cells. In the present work we showed metabolic reprogramming by means of inhibitors of histone deacetylase (HDACis), sodium butyrate and trichostatin A in breast cancer cells representing different stages of aggressiveness and metabolic profile. When testing the effect of NaB and TSA on viability of cells, it was shown that non-tumorigenic MCF-10A cells were less affected by increasing doses of the drugs than the tumorigenic, hormone dependent, tightly cohesive MCF-7, T-47D and the highly metastatic triple-negative MDA-MB 231 cells. T-47D cells were the most sensitive to treatment with both, NaB and TSA. Experiments measuring anchorage- independent growth of tumor cells showed that MCF-7, T-47D, and MDA-MB-231 cells were equally sensitive to the treatment with NaB. The NaB induced an attenuation of glycolysis, reflected by a decrease in lactate release in MCF-7 and T47D lines. Pyruvate kinase activity was significantly enhanced by NaB in MDA-MB-231 cells only. In contrast, the inhibitor enhanced lactate dehydrogenase activity specifically in T-47 D cells. Glucose-6-phosphate dehydrogenase activity was shown to be differentially modulated by NaB in the cell lines investigated: the enzyme was inhibited in MCF-7 cells, whereas in T-47D and MDA-MB-231 cells, G6PDH was activated. NaB and TSA were able to significantly increase the oxygen consumption by MDA-MB-231 and T-47D cells. Collectively the results show that epigenetic changes associated to acetylation of proteins in general affect the energy metabolism in all cancer cell lines and that mitochondria may occupy a central role in metastasis.
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Neoplasias de la Mama/metabolismo , Ácido Butírico/metabolismo , Metabolismo Energético , Inhibidores de Histona Desacetilasas/metabolismo , Ácidos Hidroxámicos/metabolismo , Línea Celular Tumoral , Glucólisis , Humanos , Redes y Vías Metabólicas , Oxidación-ReducciónRESUMEN
Methyl jasmonate (MJ), an oxylipid that induces defense-related mechanisms in plants, has been shown to be active against cancer cells both in vitro and in vivo, without affecting normal cells. Here we review most of the described MJ activities in an attempt to get an integrated view and better understanding of its multifaceted modes of action. MJ (1) arrests cell cycle, inhibiting cell growth and proliferation, (2) causes cell death through the intrinsic/extrinsic proapoptotic, p53-independent apoptotic, and nonapoptotic (necrosis) pathways, (3) detaches hexokinase from the voltage-dependent anion channel, dissociating glycolytic and mitochondrial functions, decreasing the mitochondrial membrane potential, favoring cytochrome c release and ATP depletion, activating pro-apoptotic, and inactivating antiapoptotic proteins, (4) induces reactive oxygen species mediated responses, (5) stimulates MAPK-stress signaling and redifferentiation in leukemia cells, (6) inhibits overexpressed proinflammatory enzymes in cancer cells such as aldo-keto reductase 1 and 5-lipoxygenase, and (7) inhibits cell migration and shows antiangiogenic and antimetastatic activities. Finally, MJ may act as a chemosensitizer to some chemotherapics helping to overcome drug resistant. The complete lack of toxicity to normal cells and the rapidity by which MJ causes damage to cancer cells turn MJ into a promising anticancer agent that can be used alone or in combination with other agents.
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Tumour cells thrive in environments that would be hostile to their normal cell counterparts. Survival depends on the selection of cell lines that harbour modifications of both, gene regulation that shifts the balance between the cell cycle and apoptosis and those that involve the plasticity of the metabolic machinery. With regards to metabolism, the selected phenotypes usually display enhanced anaerobic glycolysis even in the presence of oxygen, the so-called Warburg effect, and anabolic pathways that provide precursors for the synthesis of lipids, proteins and DNA. The review will discuss the original ideas of Otto Warburg and how they initially led to the notion that mitochondria of tumour cells were dysfunctional. Data will be presented to show that not only the organelles are viable and respiring, but that they are key players in tumorigenesis and metastasis. Likewise, interconnecting pathways that stand out in the tumour phenotype and that require intact mitochondria such as glutaminolysis will be addressed. Furthermore, comments will be made as to how the peculiarities of the biochemistry of tumour cells renders them amenable to new forms of treatment by highlighting possible targets for inhibitors. In this respect, a case study describing the effect of a metabolite analogue, the alkylating agent 3BP (3-bromopyruvate), on glycolytic enzyme targets will be presented.
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Metabolismo Energético/efectos de los fármacos , Neoplasias/metabolismo , Animales , Antineoplásicos/farmacología , Glutamina/metabolismo , Glucólisis , Humanos , Mitocondrias/metabolismo , Terapia Molecular Dirigida , Neoplasias/tratamiento farmacológico , Neoplasias/patologíaRESUMEN
Benign primary venous tumors are rare. While venous lipomas have been reported in the vena cava, their incidence in the remainder of the venous circulation is less well known. We present what we believe to be the first reported case of an intravascular lipoma arising from the internal jugular vein. The clinical presentation, imaging characteristics, and histologic features are presented. We also performed a review of the current literature.
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OBJECTIVE: Genomic instability is a hallmark of malignant tissues. In this work, we aimed to characterize nuclear and mitochondrial instabilities by determining short tandem repeats and somatic mitochondrial mutations, respectively, in a cohort of Brazilian sporadic breast cancer cases. Furthermore, we performed an association analysis of the molecular findings and the clinical pathological data. METHODS: We analyzed 64 matched pairs of breast cancer and adjacent non-cancerous breast samples by genotyping 13 nuclear short tandem repeat loci (namely, D2S123, TPOX, D3S1358, D3S1611, FGA, D7S820, TH01, D13S317, D13S790, D16S539, D17S796, intron 12 BRCA1 and intron 1 TP53) that were amplified with the fluorescent AmpFlSTR Identifiler Genotyping system (Applied Biosystems, USA) and by silver nitrate staining following 6% denaturing polyacrylamide gel electrophoresis. Somatic mtDNA mutations in the D-loop site were assessed with direct sequencing of the hypervariable HVI and HVII mitochondrial regions. RESULTS: Half of the cancer tissues presented some nuclear instability. Interestingly, the D13S790 locus was the most frequently affected (36%), while the D2S123 locus presented no alterations. Forty-two percent of the cases showed somatic mitochondrial mutations, the majority at region 303-315 poly-C. We identified associations between Elston grade III, instabilities at 13q31 region (p = 0.0264) and mtDNA mutations (p = 0.0041). Furthermore, instabilities at 13q31 region were also associated with TP53 mutations in the invasive ductal carcinoma cases (p= 0.0207). CONCLUSION: Instabilities at 13q31 region and the presence of somatic mtDNA mutations in a D-loop site correlated with tumor aggressiveness.
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Neoplasias de la Mama/genética , Carcinoma/genética , Cromosomas Humanos Par 13/genética , ADN Mitocondrial/genética , Inestabilidad Genómica/genética , Adulto , Distribución por Edad , Anciano , Biomarcadores de Tumor , Brasil , Neoplasias de la Mama/patología , Carcinoma/patología , Estudios de Cohortes , Femenino , Genes p53/genética , Sitios Genéticos/genética , Humanos , Pérdida de Heterocigocidad/genética , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Clasificación del TumorRESUMEN
OBJECTIVE: Genomic instability is a hallmark of malignant tissues. In this work, we aimed to characterize nuclear and mitochondrial instabilities by determining short tandem repeats and somatic mitochondrial mutations, respectively, in a cohort of Brazilian sporadic breast cancer cases. Furthermore, we performed an association analysis of the molecular findings and the clinical pathological data. METHODS: We analyzed 64 matched pairs of breast cancer and adjacent non-cancerous breast samples by genotyping 13 nuclear short tandem repeat loci (namely, D2S123, TPOX, D3S1358, D3S1611, FGA, D7S820, TH01, D13S317, D13S790, D16S539, D17S796, intron 12 BRCA1 and intron 1 TP53) that were amplified with the fluorescent AmpFlSTR Identifiler Genotyping system (Applied Biosystems, USA) and by silver nitrate staining following 6% denaturing polyacrylamide gel electrophoresis. Somatic mtDNA mutations in the D-loop site were assessed with direct sequencing of the hypervariable HVI and HVII mitochondrial regions. RESULTS: Half of the cancer tissues presented some nuclear instability. Interestingly, the D13S790 locus was the most frequently affected (36%), while the D2S123 locus presented no alterations. Forty-two percent of the cases showed somatic mitochondrial mutations, the majority at region 303-315 poly-C. We identified associations between Elston grade III, instabilities at 13q31 region (p = 0.0264) and mtDNA mutations (p = 0.0041). Furthermore, instabilities at 13q31 region were also associated with TP53 mutations in the invasive ductal carcinoma cases (p= 0.0207). CONCLUSION: Instabilities at 13q31 region and the presence of somatic mtDNA mutations in a D-loop site correlated with tumor aggressiveness.
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Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Neoplasias de la Mama/genética , Carcinoma/genética , /genética , ADN Mitocondrial/genética , Inestabilidad Genómica/genética , Distribución por Edad , Biomarcadores de Tumor , Brasil , Neoplasias de la Mama/patología , Estudios de Cohortes , Carcinoma/patología , /genética , Sitios Genéticos/genética , Pérdida de Heterocigocidad/genética , Repeticiones de Microsatélite/genética , Clasificación del TumorRESUMEN
Cancer cells display abnormal morphology, chromosomes, and metabolism. This review will focus on the metabolism of tumor cells integrating the available data by way of a functional approach. The first part contains a comprehensive introduction to bioenergetics, mitochondria, and the mechanisms of production and degradation of reactive oxygen species. This will be followed by a discussion on the oxidative metabolism of tumor cells including the morphology, biogenesis, and networking of mitochondria. Tumor cells overexpress proteins that favor fission, such as GTPase dynamin-related protein 1 (Drp1). The interplay between proapoptotic members of the Bcl-2 family that promotes Drp 1-dependent mitochondrial fragmentation and fusogenic antiapoptotic proteins such as Opa-1 will be presented. It will be argued that contrary to the widespread belief that in cancer cells, aerobic glycolysis completely replaces oxidative metabolism, a misrepresentation of Warburg's original results, mitochondria of tumor cells are fully viable and functional. Cancer cells also carry out oxidative metabolism and generally conform to the orthodox model of ATP production maintaining as well an intact electron transport system. Finally, data will be presented indicating that the key to tumor cell survival in an ROS rich environment depends on the overexpression of antioxidant enzymes and high levels of the nonenzymatic antioxidant scavengers.
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BACKGROUND: The helminth Schistosoma mansoni parasite resides in mesenteric veins where fecundated female worms lay hundred of eggs daily. Some of the egg antigens are trapped in the liver and induce a vigorous granulomatous response. High Mobility Group Box 1 (HMGB1), a nuclear factor, can also be secreted and act as a cytokine. Schistosome HMGB1 (SmHMGB1) is secreted by the eggs and stimulate the production of key cytokines involved in the pathology of schistosomiasis. Thus, understanding the mechanism of SmHMGB1 release becomes mandatory. Here, we addressed the question of how the nuclear SmHMGB1 can reach the extracellular space. PRINCIPAL FINDINGS: We showed in vitro and in vivo that CK2 phosphorylation was involved in the nucleocytoplasmic shuttling of SmHMGB1. By site-directed mutagenesis we mapped the two serine residues of SmHMGB1 that were phosphorylated by CK2. By DNA bending and supercoiling assays we showed that CK2 phosphorylation of SmHMGB1 had no effect in the DNA binding activities of the protein. We showed by electron microscopy, as well as by cell transfection and fluorescence microscopy that SmHMGB1 was present in the nucleus and cytoplasm of adult schistosomes and mammalian cells. In addition, we showed that treatments of the cells with either a phosphatase or a CK2 inhibitor were able to enhance or block, respectively, the cellular traffic of SmHMGB1. Importantly, we showed by confocal microscopy and biochemically that SmHMGB1 is significantly secreted by S. mansoni eggs of infected animals and that SmHMGB1 that were localized in the periovular schistosomotic granuloma were phosphorylated. CONCLUSIONS: We showed that secretion of SmHMGB1 is regulated by phosphorylation. Moreover, our results suggest that egg-secreted SmHMGB1 may represent a new egg antigen. Therefore, the identification of drugs that specifically target phosphorylation of SmHMGB1 might block its secretion and interfere with the pathogenesis of schistosomiasis.
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Quinasa de la Caseína II/metabolismo , ADN Protozoario/metabolismo , Proteína HMGB1/metabolismo , Schistosoma mansoni/metabolismo , Transporte Activo de Núcleo Celular , Secuencia de Aminoácidos , Animales , Núcleo Celular/metabolismo , Núcleo Celular/ultraestructura , Citosol/metabolismo , ADN Superhelicoidal/metabolismo , Pruebas de Enzimas , Femenino , Granuloma/metabolismo , Proteína HMGB1/química , Proteína HMGB1/genética , Células HeLa , Humanos , Hígado/metabolismo , Hígado/parasitología , Hígado/patología , Hígado/ultraestructura , Ratones , Datos de Secuencia Molecular , Fosforilación , Unión Proteica , Mapas de Interacción de Proteínas , Schistosoma mansoni/citología , Schistosoma mansoni/ultraestructuraRESUMEN
BACKGROUND: Tumor cells are characterized by accelerated growth usually accompanied by up-regulated pathways that ultimately increase the rate of ATP production. These cells can suffer metabolic reprogramming, resulting in distinct bioenergetic phenotypes, generally enhancing glycolysis channeled to lactate production. In the present work we showed metabolic reprogramming by means of inhibitors of histone deacetylase (HDACis), sodium butyrate and trichostatin. This treatment was able to shift energy metabolism by activating mitochondrial systems such as the respiratory chain and oxidative phosphorylation that were largely repressed in the untreated controls. METHODOLOGY/PRINCIPAL FINDINGS: Various cellular and biochemical parameters were evaluated in lung cancer H460 cells treated with the histone deacetylase inhibitors (HDACis), sodium butyrate (NaB) and trichostatin A (TSA). NaB and TSA reduced glycolytic flux, assayed by lactate release by H460 cells in a concentration dependent manner. NaB inhibited the expression of glucose transporter type 1 (GLUT 1), but substantially increased mitochondria bound hexokinase (HK) activity. NaB induced increase in HK activity was associated to isoform HK I and was accompanied by 1.5 fold increase in HK I mRNA expression and cognate protein biosynthesis. Lactate dehydrogenase (LDH) and pyruvate kinase (PYK) activities were unchanged by HDACis suggesting that the increase in the HK activity was not coupled to glycolytic flux. High resolution respirometry of H460 cells revealed NaB-dependent increased rates of oxygen consumption coupled to ATP synthesis. Metabolomic analysis showed that NaB altered the glycolytic metabolite profile of intact H460 cells. Concomitantly we detected an activation of the pentose phosphate pathway (PPP). The high O(2) consumption in NaB-treated cells was shown to be unrelated to mitochondrial biogenesis since citrate synthase (CS) activity and the amount of mitochondrial DNA remained unchanged. CONCLUSION: NaB and TSA induced an increase in mitochondrial function and oxidative metabolism in H460 lung tumor cells concomitant with a less proliferative cellular phenotype.
Asunto(s)
Metabolismo Energético/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Neoplasias Pulmonares/metabolismo , Butiratos/farmacología , Ciclo Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Permeabilidad de la Membrana Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Respiración de la Célula/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Glucosa 1-Deshidrogenasa/metabolismo , Transportador de Glucosa de Tipo 1/metabolismo , Transportador de Glucosa de Tipo 3/metabolismo , Glucólisis/efectos de los fármacos , Hexoquinasa/metabolismo , Humanos , Ácidos Hidroxámicos/farmacología , L-Lactato Deshidrogenasa/metabolismo , Lactatos/metabolismo , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/patología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Unión Proteica/efectos de los fármacos , Piruvato Quinasa/metabolismo , Succinato Deshidrogenasa/metabolismoRESUMEN
EGFR mutations have been correlated to responsiveness to treatment with tyrosine kinase inhibitors. These drugs are themselves substrates for ABC transporters. In the present work we describe the immunohistochemical profile of an archival sample from a male Brazilian patient with no Asian ancestry and never smoker, diagnosed with non-small cell lung cancer. This tumor was found to contain an in-frame hemi- or homozygous deletion, E746-A750 in exon 19 of the EGFR gene. Immunohistochemistry revealed a relatively weak staining for the ABC transporter subfamily ABCC1 and strongly for ABCB1. The cytoplasm stained positively for Bax and the nucleus stained for p53, but was negative for Bcl-2. Antibody against acetylated lysine revealed staining in both, cytoplasm and nucleus of tumor cells in contrast to normal cells which were essentially negative. The overall immunohistochemistry pattern obtained for this sample indicates that the del E746-A750 mutation may have down-regulated the expression of ABCC1. The results also suggest that the NSCLC analyzed displayed a transcriptionally active chromatin as judged by the results obtained with the anti-acetylated lysine antibody.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Genes bcl-2 , Genes erbB-1 , Genes p53 , Neoplasias Pulmonares/genética , Proteína X Asociada a bcl-2/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Adulto , Secuencia de Bases , Bancos de Muestras Biológicas , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Análisis Mutacional de ADN , Eliminación de Gen , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genes bcl-2/fisiología , Genes p53/fisiología , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Datos de Secuencia Molecular , Estudios Retrospectivos , Proteína X Asociada a bcl-2/metabolismoRESUMEN
Transplant patients are particularly at risk of developing B post-transplant lymphoproliferative disease (PTLD) related to intensive immunosuppressive treatment to prevent graft rejection. In EBV-positive PTLDs, EBV-DNA can be found in the patients' peripheral blood. Several methods have been described to assess peripheral blood EBV viral load. We report a case of a 13-year-old child who developed EBV-positive PTLD after renal transplantation. We assessed EBV plasma viral load by quantitative PCR and we found that the clearance of EBV-DNA correlated well with response to treatment.