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1.
Cancers (Basel) ; 15(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37835497

RESUMO

Cancer is a disease caused by (epi)genomic and gene expression abnormalities and characterized by metabolic phenotypes that are substantially different from the normal phenotypes of the tissues of origin. Metabolic reprogramming is one of the key features of tumors, including those established in the human nervous system. In this work, we emphasize a well-known cancerous genomic alteration: the amplification of MYCN and its downstream effects in neuroblastoma phenotype evolution. Herein, we extend our previous computational biology investigations by conducting an integrative workflow applied to published genomics datasets and comprehensively assess the impact of MYCN amplification in the upregulation of metabolism-related transcription factor (TF)-encoding genes in neuroblastoma cells. The results obtained first emphasized overexpressed TFs, and subsequently those committed in metabolic cellular processes, as validated by gene ontology analyses (GOs) and literature curation. Several genes encoding for those TFs were investigated at the mechanistic and regulatory levels by conducting further omics-based computational biology assessments applied on published ChIP-seq datasets retrieved from MYCN-amplified- and MYCN-enforced-overexpression within in vivo systems of study. Hence, we approached the mechanistic interrelationship between amplified MYCN and overexpression of metabolism-related TFs in neuroblastoma and showed that many are direct targets of MYCN in an amplification-inducible fashion. These results illuminate how MYCN executes its regulatory underpinnings on metabolic processes in neuroblastoma.

2.
J Mol Med (Berl) ; 101(4): 387-401, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36811655

RESUMO

Pediatric high-grade gliomas (pHGGs) are heterogeneous, diffuse, and highly infiltrative tumors with dismal prognosis. Aberrant post-translational histone modifications with elevated histone 3 lysine trimethylation (H3K9me3) have been recently implicated in pHGGs' pathology, conferring to tumor heterogeneity. The present study investigates the potential involvement of H3K9me3 methyltransferase SETDB1 in the cellular function, progression, and clinical significance of pHGG. The bioinformatic analysis detected SETDB1 enrichment in pediatric gliomas compared to the normal brain, as well as positive and negative correlations with a proneural and mesenchymal signature, respectively. In our cohort of pHGGs, SETDB1 expression was significantly increased compared to pLGG and normal brain tissue and correlated with p53 expression, as well as reduced patients' survival. In accordance, H3K9me3 levels were also elevated in pHGG compared to the normal brain and were associated with worse patient survival. Gene silencing of SETDB1 in two patient-derived pHGG cell lines showed a significant reduction in cell viability followed by reduced cell proliferation and increased apoptosis. SETDB1 silencing further reduced cell migration of pHGG cells and the expression of the mesenchymal markers N-cadherin and vimentin. mRNA analysis of epithelial-mesenchymal transition (EMT) markers upon SETDB1 silencing showed a reduction in SNAI1 levels and downregulation of CDH2 along with the EMT regulator gene MARCKS. In addition, SETDB1 silencing significantly increased the bivalent tumor suppressor gene SLC17A7 mRNA levels in both cell lines, indicating its implication in the oncogenic process.Altogether, our findings demonstrate a predominant oncogenic role of SETDB1 in pHGG which along with elevated H3K9me3 levels correlate significantly to tumor progression and inferior patients' survival. There is evidence that targeting SETDB1 may effectively inhibit pHGG progression, providing a novel insight into the therapeutic strategies for pediatric gliomas. KEY MESSAGES: SETDB1 gene expression is enriched in pHGG compared to normal brain. SETDB1 expression is increased in pHGG tissues and associates with reduced patients' survival. Gene silencing of SETDB1 reduces cell viability and migration. SETDB1 silencing affects mesenchymal markers expression. SETDB1 silencing upregulates SLC17A7 levels. SETDB1 has an oncogenic role in pHGG.


Assuntos
Glioma , Histonas , Humanos , Criança , Histonas/metabolismo , Histona Metiltransferases/metabolismo , Glioma/genética , Linhagem Celular , RNA Mensageiro , Histona-Lisina N-Metiltransferase/metabolismo
3.
Biochim Biophys Acta Rev Cancer ; 1877(5): 188801, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36113627

RESUMO

Pioneer transcription factors (TFs) present an important subtype of transcription factors which are vital for cell programming during embryonic development and cellular memory during mitotic growth, as well as cell fate reprogramming. Pioneer TFs can engage specific target binding sites on nucleosomal DNA to attract chromatin remodeling complexes, cofactors, and other transcription factors, ultimately controlling gene expression by shaping locally the epigenome. The priority of binding that they exhibit in contrast to other transcription factors and their involvement in crucial events regarding cell fate, has implicated their aberrant function in the pathogenesis of several disorders including carcinogenesis. Emerging experimental data indicate that certain Pioneer TFs are highly implicated in gliomas development, in neoplastic cell proliferation, angiogenic processes, resistance to therapy, and patient survival. Herein, we describe the main structural characteristics and functional mechanisms of pioneer TFs, focusing on their central role in the pathogenesis and progression of gliomas. We further highlight the current treatment options ranging from natural agents (oleanolic acid) to a variety of chemical compounds (APR-246, COTI-2) and discuss potential delivery systems, including nanoparticles, viral vectors, and intracellular protein delivery techniques.


Assuntos
Glioma , Ácido Oleanólico , Cromatina , DNA , Glioma/tratamento farmacológico , Glioma/genética , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Cancers (Basel) ; 14(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36139535

RESUMO

Non-coding segments of the human genome are enriched in cis-regulatory modules that constitute functional elements, such as transcriptional enhancers and Super-enhancers. A hallmark of cancer pathogenesis is the dramatic dysregulation of the "archetype" gene expression profiles of normal human cells. Genomic variations can promote such deficiencies when occurring across enhancers and Super-enhancers, since they affect their mechanistic principles, their functional capacity and specificity, and the epigenomic features of the chromatin microenvironment across which these regulatory elements reside. Here, we comprehensively describe: fundamental mechanisms of gene expression dysregulation in cancers that involve genomic abnormalities within enhancers' and Super-enhancers' (SEs) sequences, which alter the expression of oncogenic transcription factors (TFs); cutting-edge technologies applied for the analysis of variation-enriched hotspots of the cancer genome; and pharmacological approaches for the treatment of Super-enhancers' aberrant function. Finally, we provide an intratumor meta-analysis, which highlights that genomic variations in transcription-factor-driven tumors are accompanied overexpression of genes, a portion of which encodes for additional cancer-related transcription factors.

5.
Cancers (Basel) ; 14(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36139694

RESUMO

Gliomas encompass a vast category of CNS tumors affecting both adults and children. Treatment and diagnosis are often impeded due to intratumor heterogeneity and the aggressive nature of the more malignant forms. It is therefore essential to elucidate the molecular mechanisms and explore the intracellular signaling pathways underlying tumor pathology to provide more promising diagnostic, prognostic, and therapeutic tools for gliomas. The tripartite motif-containing (TRIM) superfamily of proteins plays a key role in many physiological cellular processes, including brain development and function. Emerging evidence supports the association of TRIMs with a wide variety of cancers, exhibiting both an oncogenic as well as a tumor suppressive role depending on cancer type. In this review, we provide evidence of the pivotal role of TRIM proteins in gliomagenesis and exploit their potential as prognostic biomarkers and therapeutic targets.

6.
Int J Mol Sci ; 23(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35409080

RESUMO

Gliomas portray a large and heterogeneous group of CNS tumors, encompassing a wide range of low- to high-grade tumors, as defined by histological and molecular characteristics. The identification of signature mutations and other molecular abnormalities has largely impacted tumor classification, diagnosis, and therapy. Transcription factors (TFs) are master regulators of gene expression programs, which ultimately shape cell fate and homeostasis. A variety of TFs have been detected to be aberrantly expressed in brain tumors, being highly implicated in critical pathological aspects and progression of gliomas. Herein, we describe a selection of oncogenic (GLI-1/2/3, E2F1-8, STAT3, and HIF-1/2) and tumor suppressor (NFI-A/B, TBXT, MYT1, and MYT1L) TFs that are deregulated in gliomas and are subsequently associated with tumor development, progression, and migratory potential. We further discuss the current targeting options against these TFs, including chemical (Bortezomib) and natural (Plumbagin) compounds, small molecules, and inhibitors, and address their potential implications in glioma therapy.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Genes Supressores de Tumor , Glioma/tratamento farmacológico , Glioma/genética , Glioma/metabolismo , Humanos , Mutação , Oncogenes
7.
Neuroimage ; 240: 118374, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34245869

RESUMO

Food cue exposure can trigger eating. Food cue reactivity (FCR) is a conditioned response to food cues and includes physiological responses and activation of reward-related brain areas. FCR can be affected by hunger and weight status. The appetite-regulating hormones ghrelin and leptin play a pivotal role in homeostatic as well as hedonic eating. We examined the association between ghrelin and leptin levels and neural FCR in the fasted and sated state and the association between meal-induced changes in ghrelin and neural FCR, and in how far these associations are related to BMI and HOMA-IR. Data from 109 participants from three European centers (age 50±18 y, BMI 27±5 kg/m2) who performed a food viewing task during fMRI after an overnight fast and after a standardized meal were analyzed. Blood samples were drawn prior to the viewing task in which high-caloric, low-caloric and non-food images were shown. Fasting ghrelin was positively associated with neural FCR in the inferior and superior occipital gyrus in the fasted state. This was partly attributable to BMI and HOMA-IR. These brain regions are involved in visual attention, suggesting that individuals with higher fasting ghrelin have heightened attention to food cues. Leptin was positively associated with high calorie FCR in the medial prefrontal cortex (PFC) in the fasted state and to neural FCR in the left supramarginal gyrus in the fasted versus sated state, when correcting for BMI and HOMA-IR, respectively. This PFC region is involved in assessing anticipated reward value, suggesting that for individuals with higher leptin levels high-caloric foods are more salient than low-caloric foods, but foods in general are not more salient than non-foods. There were no associations between ghrelin and leptin and neural FCR in the sated state, nor between meal-induced changes in ghrelin and neural FCR. In conclusion, we show modest associations between ghrelin and leptin and neural FCR in a relatively large sample of European adults with a broad age and BMI range. Our findings indicate that people with higher leptin levels for their weight status and people with higher ghrelin levels may be more attracted to high caloric foods when hungry. The results of the present study form a foundation for future studies to test whether food intake and (changes in) weight status can be predicted by the association between (mainly fasting) ghrelin and leptin levels and neural FCR.


Assuntos
Encéfalo/fisiologia , Sinais (Psicologia) , Jejum/sangue , Alimentos , Grelina/sangue , Leptina/sangue , Resposta de Saciedade/fisiologia , Adulto , Idoso , Apetite/fisiologia , Biomarcadores/sangue , Encéfalo/diagnóstico por imagem , Jejum/psicologia , Feminino , Humanos , Fome/fisiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Sobrepeso/sangue , Sobrepeso/diagnóstico por imagem , Sobrepeso/psicologia
8.
Nutrients ; 12(12)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266325

RESUMO

Understanding the mechanisms of hunger, satiety and how nutrients affect appetite control is important for successful weight management across the lifecourse. The primary aim of this study was to describe acute appetite control across the lifecourse, comparing age groups (children, adolescents, adults, elderly), weight categories, genders and European sites (Scotland and Greece). Participants (n = 391) consumed four test drinks, varying in composition (15% (normal protein, NP) and 30% (high protein, HP) of energy from protein) and quantity (based on 100% basal metabolic rate (BMR) and 140% BMR), on four separate days in a double-blind randomized controlled study. Ad libitum energy intake (EI), subjective appetite and biomarkers of appetite and metabolism (adults and elderly only) were measured. The adults' appetite was significantly greater than that of the elderly across all drink types (p < 0.004) and in response to drink quantities (p < 0.001). There were no significant differences in EI between age groups, weight categories, genders or sites. Concentrations of glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) were significantly greater in the elderly than the adults (p < 0.001). Ghrelin and fasting leptin concentrations differed significantly between weight categories, genders and sites (p < 0.05), while GLP-1 and PYY concentrations differed significantly between genders only (p < 0.05). Compared to NP drinks, HP drinks significantly increased postprandial GLP-1 and PYY (p < 0.001). Advanced age was concomitant with reduced appetite and elevated anorectic hormone release, which may contribute to the development of malnutrition. In addition, appetite hormone concentrations differed between weight categories, genders and geographical locations.


Assuntos
Apetite/fisiologia , Desjejum/psicologia , Fome/fisiologia , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Criança , Método Duplo-Cego , Ingestão de Energia/fisiologia , Feminino , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glucose/metabolismo , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo YY , Saciação/fisiologia , Inquéritos e Questionários , Adulto Jovem
9.
BMJ Case Rep ; 12(1)2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30642847

RESUMO

A 46-year-old woman was admitted with tonic-clonic seizures. She was noticed to be withdrawn and low in mood for few months. She had reduced level of consciousness with hyper-reflexia and myoclonus. Metabolic, vasculitic, autoimmune, paraneoplastic and septic screen were normal. Lumbar puncture showed raised protein in the cerebrospinal fluid but the cytology, bacterial and viral screens were negative. A CT of the head revealed global brain swelling consistent with encephalitis which was empirically treated with antibiotics and antiviral therapy. Despite this she continued to have altered sensorium. She had moderately raised titres of antithyroid peroxidise antibodies suggestive of an underlying diagnosis of Hashimoto's encephalitis. She displayed a significant improvement in her cognitive functions with high-dose steroids which was further in keeping with this rare diagnosis.


Assuntos
Encefalite/complicações , Doença de Hashimoto/complicações , Convulsões/diagnóstico , Esteroides/uso terapêutico , Diagnóstico Diferencial , Eletroencefalografia , Encefalite/diagnóstico por imagem , Encefalite/tratamento farmacológico , Encefalite/imunologia , Feminino , Pesar , Doença de Hashimoto/tratamento farmacológico , Doença de Hashimoto/imunologia , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Mioclonia/diagnóstico , Mioclonia/etiologia , Doenças Raras , Convulsões/etiologia , Convulsões/fisiopatologia , Esteroides/administração & dosagem , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
10.
BMJ Case Rep ; 20182018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30413457

RESUMO

A 30-year-old woman with polyglandular autoimmune type 2 syndrome was found collapsed at home with a cardiac arrest, which required direct current cardioversion. On admission, she was hypothermic, hypotensive and bradycardic. Initial biochemical investigations were consistent with a pre-renal acute kidney injury, metabolic acidosis and a possible sepsis. She had significantly elevated thyroid-stimulating hormone levels on admission with the clinical profile consistent with dual Addisonian and myxoedema crisis. She received intravenous liothyronine and hydrocortisone along with supportive therapy. Echo showed severe left ventricular impairment with apical ballooning although coronary angiogram disclosed nothing abnormal. She made a gradual recovery and was discharged home after 2 weeks. She was diagnosed to have primary autoimmune hypothyroidism, Addison's diseaseand type 1 diabetes and coeliac disease in October 2006, July 2007, May 2010 and September 2016, respectively. Her inability to stick to gluten-free diet at her workplace was considered a significant contributory factor for out-of-hospital cardiac arrest.


Assuntos
Doença de Addison/complicações , Doença Celíaca/complicações , Diabetes Mellitus Tipo 1/complicações , Doença de Hashimoto/complicações , Poliendocrinopatias Autoimunes/complicações , Tireoidite Autoimune/complicações , Doença de Addison/diagnóstico , Doença de Addison/tratamento farmacológico , Agonistas Adrenérgicos beta/uso terapêutico , Adulto , Anti-Inflamatórios/uso terapêutico , Doença Celíaca/diagnóstico , Doença Celíaca/dietoterapia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Dieta Livre de Glúten , Cardioversão Elétrica , Feminino , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/tratamento farmacológico , Parada Cardíaca/diagnóstico , Parada Cardíaca/etiologia , Parada Cardíaca/terapia , Humanos , Hidrocortisona/uso terapêutico , Isoproterenol/uso terapêutico , Poliendocrinopatias Autoimunes/diagnóstico , Poliendocrinopatias Autoimunes/tratamento farmacológico , Tireoidite Autoimune/diagnóstico , Tireoidite Autoimune/tratamento farmacológico , Tri-Iodotironina/uso terapêutico
11.
Appl Physiol Nutr Metab ; 41(7): 714-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27176936

RESUMO

This study examined changes in salivary testosterone and cortisol following resistance and plyometric exercise protocols in active boys. In a crossover experimental design, 26 peri-pubertal (12- to 14-year-old) soccer players performed 2 exercise trials in random order, on separate evenings, 1 week apart. Each trial included a 30 min control session followed by 30 min of either resistance or plyometric exercise. Saliva was collected at baseline, post-control (i.e., pre-exercise), and 5 and 30 min post-exercise. There were no significant differences in the baseline hormone concentrations between trials or between weeks (p > 0.05). A significant effect for time was found for testosterone (p = 0.02, [Formula: see text] = 0.14), which increased from pre-exercise to 5 min post-exercise in both the resistance (27% ± 5%) and plyometric (12% ± 6%) protocols. Cortisol decreased to a similar extent in both trials (p = 0.009, [Formula: see text] = 0.19) from baseline to post-control and then to 5 min post-exercise, following its typical circadian decrease in the evening hours. However, a significant protocol-by-time interaction was observed for cortisol, which increased 30 min after the plyometrics (+31% ± 12%) but continued to decrease following the resistance protocol (-21% ± 5%). Our results suggest that in young male athletes, multiple modes of exercise can lead to a transient anabolic state, thus maximizing the beneficial effects on growth and development, when exercise is performed in the evening hours.


Assuntos
Hidrocortisona/química , Exercício Pliométrico , Treinamento Resistido , Saliva/química , Testosterona/química , Adolescente , Atletas , Índice de Massa Corporal , Criança , Estudos Cross-Over , Humanos , Masculino , Futebol
12.
Biomed Res Int ; 2013: 423263, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24455693

RESUMO

The aim of the present study was to investigate the associations of iron depletion (ID) with menstrual blood losses, lifestyle, and dietary habits, in pubertal girls. The study sample comprised 1222 girls aged 9-13 years old. Biochemical, anthropometrical, dietary, clinical, and physical activity data were collected. Out of 274 adolescent girls with menses, 33.5% were found to be iron depleted (defined as serum ferritin < 12 µg/L) compared to 15.9% out of 948 girls without menses. Iron-depleted girls without menses were found to have lower consumption of poultry (P = 0.017) and higher consumption of fruits (P = 0.044) and fast food (P = 0.041) compared to their peers having normal iron status. Multivariate logistic regression analysis showed that girls with menses were 2.57 (95% CI: 1.37, 4.81) times more likely of being iron depleted compared to girls with no menses. Iron depletion was found to be associated with high calcium intake, high consumption of fast foods, and low consumption of poultry and fruits. Menses was the only factor that was found to significantly increase the likelihood of ID in these girls. More future research is probably needed in order to better understand the role of diet and menses in iron depletion.


Assuntos
Hemorragia/metabolismo , Ferro/sangue , Menstruação/metabolismo , Adolescente , Antropometria , Cálcio/metabolismo , Criança , Dieta , Feminino , Ferritinas/sangue , Humanos , Menstruação/fisiologia
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