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1.
Endocr Connect ; 9(11): 1065-1074, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33112820

RESUMO

The PI3K-Akt-mTOR pathway plays a central role in the development of non-medullary thyroid carcinoma (NMTC). Although somatic mutations have been identified in these genes in NMTC patients, the role of germline variants has not been investigated. Here, we selected frequently occurring genetic variants in AKT1, AKT2, AKT3, PIK3CA and MTOR and have assessed their effect on NMTC susceptibility, progression and clinical outcome in a Dutch discovery cohort (154 patients, 188 controls) and a Romanian validation cohort (159 patients, 260 controls). Significant associations with NMTC susceptibility were observed for AKT1 polymorphisms rs3803304, rs2494732 and rs2498804 in the Dutch discovery cohort, of which the AKT1 rs3803304 association was confirmed in the Romanian validation cohort. No associations were observed between PI3K-Akt-mTOR polymorphisms and clinical parameters including histology, TNM staging, treatment response and clinical outcome. Functionally, cells bearing the associated AKT1 rs3803304 risk allele exhibit increased levels of phosphorylated Akt protein, potentially leading to elevated signaling activity of the oncogenic Akt pathway. All together, germline encoded polymorphisms in the PI3K-Akt-mTOR pathway could represent important risk factors in development of NMTC.

2.
Artigo em Inglês | MEDLINE | ID: mdl-30705668

RESUMO

Background: Metabolomics-the novel science that evaluates the multitude of low-molecular-weight metabolites in a biological system, provides new data on pathogenic mechanisms of diseases, including endocrine tumors. Although development of metabolomic profiling in pituitary disorders is at an early stage, it seems to be a promising approach in the near future in identifying specific disease biomarkers and understanding cellular signaling networks. Objectives: To review the metabolomic profile and the contributions of metabolomics in pituitary adenomas (PA). Methods: A systematic review was conducted via PubMed, Web of Science Core Collection and Scopus databases, summarizing studies that have described metabolomic aspects of PA. Results: Liquid chromatography tandem mass spectrometry (LC-MS/MS) and nuclear magnetic resonance (NMR) spectrometry, which are traditional techniques employed in metabolomics, suggest amino acids metabolism appears to be primarily altered in PA. N-acetyl aspartate, choline-containing compounds and creatine appear as highly effective in differentiating PA from healthy tissue. Deoxycholic and 4-pyridoxic acids, 3-methyladipate, short chain fatty acids and glucose-6-phosphate unveil metabolite biomarkers in patients with Cushing's disease. Phosphoethanolamine, N-acetyl aspartate and myo-inositol are down regulated in prolactinoma, whereas aspartate, glutamate and glutamine are up regulated. Phosphoethanolamine, taurine, alanine, choline-containing compounds, homocysteine, and methionine were up regulated in unclassified PA across studies. Intraoperative use of ultra high mass resolution matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI), which allows localization and delineation between functional PA and healthy pituitary tissue, may contribute to achievement of complete tumor resection in addition to preservation of pituitary cell lines and vasopressin secretory cells, thus avoiding postoperative diabetes insipidus. Conclusion: Implementation of ultra high performance metabolomics analysis techniques in the study of PA will significantly improve diagnosis and, potentially, the therapeutic approach, by identifying highly specific disease biomarkers in addition to novel molecular pathogenic mechanisms. Ultra high mass resolution MALDI-MSI emerges as a helpful clinical tool in the neurosurgical treatment of pituitary tumors. Therefore, metabolomics appears to be a science with a promising prospect in the sphere of PA, and a starting point in pituitary care.

3.
Endocr Relat Cancer ; 24(7): 307-318, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28428267

RESUMO

The NF-κB inflammatory pathway plays a major role in cancer development and clinical progression. Activation of NF-κB signaling is promoted by NFKB1 and inhibited by NFKBIA. The present study aimed to determine the relevance of NFKB1 rs4648068 and NFKBIA rs2233406 genetic variants for non-medullary thyroid cancer (NMTC) susceptibility, progression and clinical outcome. This case-control and cohort study consists of a Romanian discovery cohort (157 patients and 258 controls) and a Dutch validation cohort (138 patients and 188 controls). In addition, patient cohorts were analyzed further for the association of genetic variants with clinical parameters. Functional studies were performed on human peripheral blood mononuclear cells. No associations were observed between the studied genetic variants and TC susceptibility. Although no statistically significant associations with clinical parameters were observed for NFKB1 rs4648068, the heterozygous genotype of NFKBIA rs2233406 was correlated with decreased radioactive iodide sensitivity requiring higher cumulative dosages to achieve clinical response. These findings were discovered in the Romanian cohort (P < 0.001) and confirmed in the Dutch cohort (P = 0.01). Functional studies revealed that this NFKBIA rs2233406 genotype was associated with elevated TLR4-mediated IL-1ß production. In conclusion, genetic variation in NFKBIA, an inhibitor of NF-κB signaling, is associated with clinical response to RAI therapy and with increased production of the pro-inflammatory cytokine IL-1ß, providing a potential mechanism for the observed clinical associations. These data suggest that NF-κB signaling is involved in NMTC pathogenesis and that the inflammatory tumor microenvironment could contribute to RAI resistance.


Assuntos
NF-kappa B/genética , Neoplasias da Glândula Tireoide/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Neoplasias da Glândula Tireoide/patologia , Adulto Jovem
4.
Scand J Clin Lab Invest ; 76(3): 217-25, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26922969

RESUMO

BACKGROUND: Visfatin is a proinflammatory molecule with possible actions on glucose metabolism. Interactions to bone metabolism and undercarboxylated osteocalcin (uOC) in diabetic patients (T2DP) with diabetic kidney disease (DKD) have not been reported. MATERIALS AND METHODS: We included 51 incident T2DP with DKD. History, laboratory evaluation, anthropometry, visfatin, uOC were obtained. Fifteen T2DP without DKD were used as controls. RESULTS: Visfatin was similar in DKD patients and controls: 1.56(0.97-3.03) versus 2.04(1.08-3.21) ng/mL, p = 0.51. In controls, visfatin positively correlated with diabetes duration (r = 0.63, p = 0.01) and negatively with uOC (r = -0.57, p = 0.03). In multivariate regression, diabetes duration remained significant (p = 0.01). In patients with DKD, visfatin was positively linked to C reactive protein (r = 0.27, p = 0.05), tricipital skin fold (TSF) (r = 0.41, p = 0.004) and leukocytes (r = 0.37, p = 0.01); the latter two parameters predicted visfatin in multivariate model (p = 0.001). In normoalbuminuric patients, visfatin was linked to body mass index (r = 0.32, p = 0.04), waist circumference (r = 0.42, p < 0.0001), LDL cholesterol (r = 0.33, p = 0.03), serum glucose (r = 0.36, p = 0.03) and glycated hemoglobin (r = 0.41, p = 0.007); there was a trend towards negative correlation to uOC (r = -0.28, p = 0.07); only glycaemia remained significant in multivariate analysis (p = 0.04). Albuminuric patients displayed a positive correlation of visfatin to waist to hip ratio (r = 0.41, p = 0.04) and leukocytes (r = 0.56, p = 0.04); the latter remained significant in multivariate regression (p = 0.005). CONCLUSION: The main determinant of visfatin in T2D patients with DKD is inflammation; in normoalbuminuric patients, a positive link to adiposity and altered glycemic control and a trend towards a negative correlation to uOC was observable; the latter relationship was evident in patients without DKD.


Assuntos
Adiposidade , Citocinas/sangue , Diabetes Mellitus Tipo 2/sangue , Nefropatias Diabéticas/sangue , Nicotinamida Fosforribosiltransferase/sangue , Osteocalcina/sangue , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/fisiopatologia , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/fisiopatologia , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade
5.
Artigo em Inglês | MEDLINE | ID: mdl-26869991

RESUMO

PubMed, Scopus, and Web of Science Core Collection databases were systematically searched for studies reporting synchronous double or multiple pituitary adenomas (MPA), a rare clinical condition, with a vague pathogenesis. Multiple adenomas of the pituitary gland are referred to as morphologically and/or immunocytochemically distinct tumors that are frequently small-sized and hormonally non-functional, to account for the low detection rate. There is no general agreement on how to classify MPA, various criteria, such as tumor contiguity, immunoreactivity, and clonality analysis are being used. Among the component tumors, prolactin (PRL)-immunopositive adenomas are highly prevalent, albeit mute in the majority of cases. The most frequent clinical presentation of MPA is Cushing's syndrome, given the fact that in more than 50% of reported cases at least one lesion stains for adrenocorticotrophic hormone (ACTH). Plurihormonal hyperactivity may be diagnosed in a patient with MPA when more than one tumor is clinically active (e.g., ACTH and PRL) or in cases with at least one composite tumor (e.g., GH and PRL), to complicate the clinical scenario. Specific challenges associated with MPA include high surgical failure rates, enforcing second-look surgery in certain cases, and difficult preoperative neuroradiological imaging evaluation, with an overall sensitivity of only 25% for magnetic resonance imaging to detect distinct multiple tumors. Alternatively, minor pituitary imaging abnormalities may raise suspicion, as these are not uncommon. Postoperative immunohistochemistry is mandatory and in conjunction to electron microscopy scanning and testing for transcription factors (i.e., Pit-1, T-pit, and SF-1) accurately define and classify the distinct cytodifferentiation of MPA.

6.
Adv Clin Chem ; 71: 25-45, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26411410

RESUMO

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women of reproductive age affecting various functions including reproduction and metabolism. This syndrome is associated with increased prevalence of subclinical cardiovascular disease as well as endometrial and ovarian cancer. This syndrome is highly heterogeneous and it is not yet clear which factors are responsible for the development of a particular phenotype. Current research has shown that the interaction of susceptible and protective genomic variants under the influence of environmental factors can modify the clinical presentation via epigenetic modifications. MicroRNA (miRNA) are regulators of gene expression. Altered miRNA expression has been associated with various diseases such as diabetes, insulin resistance, inflammation, and cancer. Several miRNA have been identified in PCOS. This review examines the role of epigenetics and miRNA in the pathophysiology of this complex disease process.


Assuntos
Epigênese Genética , MicroRNAs , Síndrome do Ovário Policístico/genética , Animais , Biomarcadores/metabolismo , Feminino , Folistatina/genética , Humanos , Lamina Tipo A/genética , MicroRNAs/genética , PPAR gama/genética , Síndrome do Ovário Policístico/fisiopatologia
7.
Cancer Treat Rev ; 41(8): 707-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26138515

RESUMO

Thyroid carcinoma (TC) is the most common endocrine malignancy. The pathogenesis of TC is complex and involves multiple genetic events that lead to activation of oncogenic pathways such as the MAP kinase (MAPK) pathway and the PI3K/Akt/mTOR pathway. The PI3K/Akt pathway has emerged as an important player in the pathogenesis of TC, particularly in follicular and advanced anaplastic or poorly differentiated TC. Because these patients have a poor prognosis, particularly when their tumors become resistant to the conventional treatment with radioactive iodine, efforts have been made to identify possible targets for therapy within these pathways. Orally available drugs targeting the PI3K/Akt/mTOR pathway are being used with success in treatment of several types of malignant tumors. There is an increasing amount of preclinical and clinical data supporting that this pathway may represent a promising target for systemic therapy in TC. The present review focuses on the most recent developments on the role of the PI3K/Akt pathway in the pathogenesis of non-medullary TC and will provide insight into how this pathway can be targeted either alone or in the context of multimodal therapeutic strategies for treatment of advanced TC.


Assuntos
Carcinoma , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas c-akt/genética , Serina-Treonina Quinases TOR/genética , Neoplasias da Glândula Tireoide , Fatores de Transcrição/genética , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinoma/tratamento farmacológico , Carcinoma/genética , Carcinoma/patologia , Carcinoma Papilar , Gerenciamento Clínico , Resistencia a Medicamentos Antineoplásicos , Humanos , Terapia de Alvo Molecular/métodos , Terapia de Alvo Molecular/tendências , Mutação , Transdução de Sinais/genética , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia
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