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1.
J Biol Chem ; 300(3): 105767, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38367672

RESUMO

Approximately 5 to 15% of nonmedullary thyroid cancers (NMTC) present in a familial form (familial nonmedullary thyroid cancers [FNMTC]). The genetic basis of FNMTC remains largely unknown, representing a limitation for diagnostic and clinical management. Recently, germline mutations in DNA repair-related genes have been described in cases with thyroid cancer (TC), suggesting a role in FNMTC etiology. Here, two FNMTC families were studied, each with two members affected with TC. Ninety-four hereditary cancer predisposition genes were analyzed through next-generation sequencing, revealing two germline CHEK2 missense variants (c.962A > C, p.E321A and c.470T > C, p.I157T), which segregated with TC in each FNMTC family. p.E321A, located in the CHK2 protein kinase domain, is a rare variant, previously unreported in the literature. Conversely, p.I157T, located in CHK2 forkhead-associated domain, has been extensively described, having conflicting interpretations of pathogenicity. CHK2 proteins (WT and variants) were characterized using biophysical methods, molecular dynamics simulations, and immunohistochemistry. Overall, biophysical characterization of these CHK2 variants showed that they have compromised structural and conformational stability and impaired kinase activity, compared to the WT protein. CHK2 appears to aggregate into amyloid-like fibrils in vitro, which opens future perspectives toward positioning CHK2 in cancer pathophysiology. CHK2 variants exhibited higher propensity for this conformational change, also displaying higher expression in thyroid tumors. The present findings support the utility of complementary biophysical and in silico approaches toward understanding the impact of genetic variants in protein structure and function, improving the current knowledge on CHEK2 variants' role in FNMTC genetic basis, with prospective clinical translation.


Assuntos
Quinase do Ponto de Checagem 2 , Síndromes Neoplásicas Hereditárias , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Quinase do Ponto de Checagem 2/química , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Síndromes Neoplásicas Hereditárias/genética , Estudos Prospectivos , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Domínios Proteicos , Masculino , Feminino , Pessoa de Meia-Idade
2.
Int J Mol Sci ; 25(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38396644

RESUMO

Germline variants in the FOXE1 transcription factor have been associated with thyroid ectopy, cleft palate (CP) and thyroid cancer (TC). Here, we aimed to clarify the role of FOXE1 in Portuguese families (F1 and F2) with members diagnosed with malignant struma ovarii (MSO), an ovarian teratoma with ectopic malignant thyroid tissue, papillary TC (PTC) and CP. Two rare germline heterozygous variants in the FOXE1 promoter were identified: F1) c.-522G>C, in the proband (MSO) and her mother (asymptomatic); F2) c.9C>T, in the proband (PTC), her sister and her mother (CP). Functional studies using rat normal thyroid (PCCL3) and human PTC (TPC-1) cells revealed that c.9C>T decreased FOXE1 promoter transcriptional activity in both cell models, while c.-522G>C led to opposing activities in the two models, when compared to the wild type. Immunohistochemistry and RT-qPCR analyses of patients' thyroid tumours revealed lower FOXE1 expression compared to adjacent normal and hyperplastic thyroid tissues. The patient with MSO also harboured a novel germline AXIN1 variant, presenting a loss of heterozygosity in its benign and malignant teratoma tissues and observable ß-catenin cytoplasmic accumulation. The sequencing of the F1 (MSO) and F2 (PTC) probands' tumours unveiled somatic BRAF and HRAS variants, respectively. Germline FOXE1 and AXIN1 variants might have a role in thyroid ectopy and cleft palate, which, together with MAPK pathway activation, may contribute to tumours' malignant transformation.


Assuntos
Fissura Palatina , Cisto Dermoide , Fatores de Transcrição Forkhead , Neoplasias Ovarianas , Estruma Ovariano , Neoplasias da Glândula Tireoide , Animais , Feminino , Humanos , Ratos , Fissura Palatina/genética , Cisto Dermoide/genética , Fatores de Transcrição Forkhead/genética , Neoplasias Ovarianas/metabolismo , Estruma Ovariano/genética , Estruma Ovariano/metabolismo , Estruma Ovariano/patologia , Neoplasias da Glândula Tireoide/patologia
3.
Endocrine ; 84(2): 625-634, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38102497

RESUMO

PURPOSE: Radioiodine (RAI) therapy remains the gold-standard approach for distant metastatic differentiated thyroid cancer (TC). The main objective of our work was to identify the clinical and molecular markers that may help to predict RAI avidity and RAI therapy response of metastatic lesions in a cohort of papillary thyroid cancer (PTC) patients. METHODS: We performed a retrospective analysis of 122 PTC patients submitted to RAI therapy due to distant metastatic disease. We also analysed, through next-generation sequencing, a custom panel of 78 genes and rearrangements, in a smaller cohort of 31 metastatic PTC, with complete follow-up, available RAI therapy data, and existing tumour sample at our centre. RESULTS: The most frequent outcome after RAI therapy was progression of disease in 59.0% of cases (n = 71), with median estimate progression-free survival of 30 months. RAI avidity was associated with PTC subtype, age and stimulated thyroglobulin at first RAI therapy for metastatic disease. The most frequently altered genes in the cohort of 31 PTC patients' primary tumours were RAS isoforms (54.8%) and TERT promoter (TERTp) (51.6%). The presence of BRAF p.V600E or RET/PTC alterations was associated with lower avidity (p = 0.012). TERTp mutations were not associated with avidity (p = 1.000) but portended a tendency for a higher rate of progression (p = 0.063); similar results were obtained when RAS and TERTp mutations coexisted (p = 1.000 and p = 0.073, respectively). CONCLUSIONS: Early identification of molecular markers in primary tumours may help to predict RAI therapy avidity, the response of metastatic lesions and to select the patients that may benefit the most from other systemic therapies.


Assuntos
Radioisótopos do Iodo , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Feminino , Masculino , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/radioterapia , Câncer Papilífero da Tireoide/patologia , Radioisótopos do Iodo/uso terapêutico , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Estudos Retrospectivos , Adulto , Idoso , Resultado do Tratamento , Telomerase/genética , Adulto Jovem , Metástase Neoplásica , Idoso de 80 Anos ou mais
4.
Front Endocrinol (Lausanne) ; 14: 1247542, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37964967

RESUMO

Background: CDK4/6 inhibitors (CDK4/6i) have been established as standard treatment against advanced Estrogen Receptor-positive breast cancers. These drugs are being tested against several cancers, including in combinations with other therapies. We identified the T172-phosphorylation of CDK4 as the step determining its activity, retinoblastoma protein (RB) inactivation, cell cycle commitment and sensitivity to CDK4/6i. Poorly differentiated (PDTC) and anaplastic (ATC) thyroid carcinomas, the latter considered one of the most lethal human malignancies, represent major clinical challenges. Several molecular evidence suggest that CDK4/6i could be considered for treating these advanced thyroid cancers. Methods: We analyzed by two-dimensional gel electrophoresis the CDK4 modification profile and the presence of T172-phosphorylated CDK4 in a collection of 98 fresh-frozen tissues and in 21 cell lines. A sub-cohort of samples was characterized by RNA sequencing and immunohistochemistry. Sensitivity to CDK4/6i (palbociclib and abemaciclib) was assessed by BrdU incorporation/viability assays. Treatment of cell lines with CDK4/6i and combination with BRAF/MEK inhibitors (dabrafenib/trametinib) was comprehensively evaluated by western blot, characterization of immunoprecipitated CDK4 and CDK2 complexes and clonogenic assays. Results: CDK4 phosphorylation was detected in all well-differentiated thyroid carcinomas (n=29), 19/20 PDTC, 16/23 ATC and 18/21 thyroid cancer cell lines, including 11 ATC-derived ones. Tumors and cell lines without phosphorylated CDK4 presented very high p16CDKN2A levels, which were associated with proliferative activity. Absence of CDK4 phosphorylation in cell lines was associated with CDK4/6i insensitivity. RB1 defects (the primary cause of intrinsic CDK4/6i resistance) were not found in 5/7 tumors without detectable phosphorylated CDK4. A previously developed 11-gene expression signature identified the likely unresponsive tumors, lacking CDK4 phosphorylation. In cell lines, palbociclib synergized with dabrafenib/trametinib by completely and permanently arresting proliferation. These combinations prevented resistance mechanisms induced by palbociclib, most notably Cyclin E1-CDK2 activation and a paradoxical stabilization of phosphorylated CDK4 complexes. Conclusion: Our study supports further clinical evaluation of CDK4/6i and their combination with anti-BRAF/MEK therapies as a novel effective treatment against advanced thyroid tumors. Moreover, the complementary use of our 11 genes predictor with p16/KI67 evaluation could represent a prompt tool for recognizing the intrinsically CDK4/6i insensitive patients, who are potentially better candidates to immediate chemotherapy.


Assuntos
Imidazóis , Oximas , Prolina/análogos & derivados , Tiocarbamatos , Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Fosforilação , Proteínas Proto-Oncogênicas B-raf/genética , Linhagem Celular Tumoral , Neoplasias da Glândula Tireoide/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Quinase 4 Dependente de Ciclina
6.
Eur J Endocrinol ; 188(1)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36651156

RESUMO

OBJECTIVES: Anaplastic thyroid carcinoma (ATC) has a poor survival. The combination of Dabrafenib plus Trametinib (DT) had a significant impact in survival of BRAF p.V600E patients. However, durable responses may be compromised by resistance. We aim to present our experience with DT in BRAF positive ATC patients and compare the outcomes with usual therapy, and to study tumor molecular alterations in the DT group. METHODS: Patients treated between May 2018 and April 2022 in a tertiary referral center, assessed for BRAF status were included. Patients were divided in three groups: BRAF p.V600E treated with DT, BRAF wild type (WT) under multimodal therapy (MT), and BRAF WT under compassionate care (CC). Response was assessed monthly in the first 6 months and every 3 months afterwards, by RECIST 1.1. Overall survival (OS) and progression-free survival (PFS) were estimated with the Kaplan-Meier method and compared with the log-rank test. RESULTS: Twenty-seven ATC patients were included (DT = 9, MT = 8, and CC = 10). Median OS was 475 days for DT, 156 days for MT, and 39 days for CC (P < .001). At 12 months, only patients in the DT group were alive (71%). Median PFS was 270 days, in the DT group, compared with less than 32 days in BRAF WT (P < .001). No severe adverse events were reported. Molecular profiling showed that in one of the four clinical progressions, a pathogenic NRAS mutation was found. CONCLUSIONS: Our results show a significant real-world efficacy of Dabrafenib plus Trametinib in both survival and recurrence compared with standard treatment, with a good safety profile.


Assuntos
Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Carcinoma Anaplásico da Tireoide/genética , Carcinoma Anaplásico da Tireoide/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Intervalo Livre de Doença , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Mutação
7.
Clin Endocrinol (Oxf) ; 97(3): 250-257, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35120263

RESUMO

OBJECTIVE: Parathyroid Carcinoma is a rare malignant neoplasm, accounting for less than 1% of primary hyperparathyroidism cases. Parathyroid carcinomas are characterized by markedly elevated levels of PTH, severe hypercalcemia and established target organ damage. The authors report the experience of a single centre regarding the management and outcome of patients with parathyroid carcinomas and revise relevant literature. DESIGN: Retrospective review of all patients with parathyroid carcinoma evaluated at a tertiary oncologic centre from 1991 until 2021. RESULTS: Seventeen patients were identified (10 males), with a mean age at diagnosis of 53 ± 16 years and a median follow-up of 16.5 years. Most patients presented with hypercalcemia (n = 15), with a mean serum calcium concentration of 13.5 mg/dl (9.6-16.5) and mean PTH of 1173 pg/ml (276-2500). Hyperparathyroidism-mediated organ damage was observed in most patients (n = 16), with predominant renal (n = 12) and skeletal (n = 9) complications. En bloc surgical resection was performed in nine patients. Three patients underwent adjuvant radiotherapy. Recurrence was observed in 8 cases (47.1%) after a median of 24 months following surgery and no independent predictors of recurrence were identified. The overall survival and disease specific survival at 5-year was 88% and 94%, respectively. CDC73 mutations were present in 38.5% of analysed patients and one patient was diagnosed with MEN1. CONCLUSION: Parathyroid carcinoma is associated with a significant rate of recurrence and limited effective treatment beyond initial complete surgical resection. Therefore, preoperatively high index of suspicion is paramount to optimize patient care. This is, to our knowledge, the largest Portuguese cohort published so far.


Assuntos
Hipercalcemia , Hiperparatireoidismo , Neoplasias das Paratireoides , Adulto , Idoso , Feminino , Humanos , Hipercalcemia/etiologia , Hiperparatireoidismo/genética , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo , Neoplasias das Paratireoides/complicações , Neoplasias das Paratireoides/genética , Neoplasias das Paratireoides/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
8.
Medicine (Baltimore) ; 100(49): e28145, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34889280

RESUMO

RATIONALE: Multiple Endocrine Neoplasia type 1 (MEN1) is a familial syndrome that results from the disruption of a tumor suppressor protein called MENIN. Its management is challenging, as MEN1 affects different endocrine tissues and predisposes to both benign and malignant tumors. MENIN-deficient cells have recently been recognized to play a role in triggering autoimmunity. Herein, we present a case of MEN1 with multiple endocrine and autoimmune disorders. PATIENT CONCERNS: A 50 years old female with a 25 years history of complicated nephrolithiasis presented with primary hyperparathyroidism. DIAGNOSES: Over several decades, she was diagnosed with recurrent primary hyperparathyroidism, autoimmune thyroiditis, multinodular goiter, pernicious anemia, metastatic gastric type 1 neuroendocrine tumor, macroprolactinemia, gonadotropin deficiency, mucosa-associated lymphoid tissue lymphoma of the thyroid gland, positive anti-calcium sensor receptor antibodies, and BRCA 1/2-negative invasive breast cancer. The autoimmune regulator gene was sequenced, but no pathogenic variants were found. Next-generation sequencing revealed both a pathogenic MEN1 mutation and a benign CDC73 gene variant. Familial genetic screening revealed a large kindred with multiple carriers of one or both genetic variants (MEN1 = 19; CDC73 = 7). INTERVENTIONS: The patient underwent surgical excision of three parathyroid glands, total thyroidectomy and breast tumorectomy plus tamoxifen, and monthly injections of octreotide. The patient and family members with the MEN1 mutation are under a life-long surveillance program for MEN1 prototypic tumors. OUTCOMES: The patient was stable and alive during a 24-years follow-up period. LESSONS: With the present case, the authors highlight a new interplay between MENIN and the immune system, which may have implications for future targeted life-long surveillance and treatment of MEN1 patients.


Assuntos
Doenças Autoimunes , Hiperparatireoidismo Primário/complicações , Neoplasia Endócrina Múltipla Tipo 1/complicações , Doenças Autoimunes/complicações , Autoimunidade , Feminino , Humanos , Hiperparatireoidismo Primário/cirurgia , Neoplasias Intestinais , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/genética , Neoplasia Endócrina Múltipla Tipo 1/cirurgia , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas , Neoplasias Gástricas , Tireoidectomia
9.
Thyroid ; 31(9): 1366-1375, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33906393

RESUMO

Background: The molecular basis of familial nonmedullary thyroid cancer (FNMTC) is still poorly understood, representing a limitation for molecular diagnosis and clinical management. In this study, we aimed to identify new susceptibility genes for FNMTC through whole-exome sequencing (WES) analysis of leukocyte DNA of patients from a highly informative FNMTC family. Methods: We selected six affected family members to conduct WES analysis. Bioinformatic analyses were undertaken to filter and select the genetic variants shared by the affected members, which were subsequently validated by Sanger sequencing. To select the most likely pathogenic variants, several studies were performed, including family segregation analysis, in silico impact characterization, and gene expression (messenger RNA and protein) depiction in databases. For the most promising variant identified, we performed in vitro studies to validate its pathogenicity. Results: Several potentially pathogenic variants were identified in different candidate genes. After filtering with appropriate criteria, the variant c.701C>T, p.Thr234Met in the SPRY4 gene was prioritized for in vitro functional characterization. This SPRY4 variant led to an increase in cell viability and colony formation, indicating that it confers a proliferative advantage and potentiates clonogenic capacity. Phosphokinase array and Western blot analyses suggested that the effects of the SPRY4 variant were mediated through the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway, which was further supported by a higher responsiveness of thyroid cancer cells with the SPRY4 variant to a MEK inhibitor. Conclusions: WES analysis in one family identified SPRY4 as a likely novel candidate susceptibility gene for FNMTC, allowing a better understanding of the cellular and molecular mechanisms underlying thyroid cancer development.


Assuntos
Biomarcadores Tumorais/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas do Tecido Nervoso/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Animais , Linhagem Celular Tumoral , Análise Mutacional de DNA , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Predisposição Genética para Doença , Hereditariedade , Humanos , Masculino , Camundongos , Células NIH 3T3 , Linhagem , Fenótipo , Transdução de Sinais , Câncer Papilífero da Tireoide/metabolismo , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Sequenciamento do Exoma
10.
Genes (Basel) ; 11(4)2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32276436

RESUMO

Cutaneous melanoma is one of the most aggressive human cancers due to its high invasiveness. Germline mutations in high-risk melanoma susceptibility genes have been associated with development hereditary melanoma; however, most genetic culprits remain elusive. To unravel novel susceptibility genes for hereditary melanoma, we performed whole exome sequencing (WES) on eight patients with multiple primary melanomas, high number of nevi, and negative for high and intermediate-risk germline mutations. Thirteen new potentially pathogenic variants were identified after bioinformatics analysis and validation. CDH23, ARHGEF40, and BRD9 were identified as the most promising susceptibility genes in hereditary melanoma. In silico analysis of CDH23 and ARHGEF40 variants provided clues for altered protein structure and function associated with the identified mutations. Then, we also evaluated the clinical value of CDH23, ARHGEF40, and BRD9 expression in sporadic melanoma by using the TCGA dataset (n = 461). No differences were observed in BRD9 expression between melanoma and normal skin samples, nor with melanoma stage, whereas ARHGEF40 was found overexpressed, and CDH23 was downregulated and its loss was associated with worse survival. Altogether, these results reveal three novel genes with clinical relevance in hereditary and sporadic melanoma.


Assuntos
Caderinas/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Melanoma/genética , Fatores de Transcrição/genética , Adulto , Idoso , Proteínas Relacionadas a Caderinas , Exoma/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Sequenciamento do Exoma/métodos
11.
Nutr Cancer ; 72(2): 352-363, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31287730

RESUMO

Aim: Anaplastic thyroid cancer (ATC) is the most aggressive subtype of thyroid cancer, presenting high mortality. Currently, no curative treatments exist and new therapeutic strategies are required. Although nutraceuticals were reported to have anticancer properties, few studies exist on ATC. This study aimed to investigate the anticancer effects of nutraceuticals in ATC cell lines (T235, T238) in comparison with normal thyroid cells (PCCL3).Methods: The IC50 values of isothiocyanates (ITCs: sulforaphane, SFN; phenethyl isothiocyanate, PEITC) and polymethoxylated flavones (PMFs: nobiletin; orange peel extract, OPE) were determined. ITCs decreased ATC metabolic viability more efficiently than PMFs. The effects of PEITC and nobiletin on viability and cell cycle, alone or in combination with conventional drugs, were evaluated.Results: PEITC did not affect viability of normal thyroid and ATC cells, while nobiletin decreased viability in a dose-dependent manner in all cell lines, although cell cycle was not arrested. At 100 µM, nobiletin reduced ATC cell viability as efficiently as conventional drugs, such as cisplatin, while being less toxic to normal thyroid cells. When conjugated with 1 µM cisplatin, the combination decreased viability of T235 cells more efficiently than each compound alone.Conclusion: These results suggest nobiletin as a potential anticancer agent that warrants further investigation in ATC.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Cisplatino/farmacologia , Flavonas/farmacologia , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Apoptose , Sobrevivência Celular , Suplementos Nutricionais , Quimioterapia Combinada , Humanos , Carcinoma Anaplásico da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Células Tumorais Cultivadas
12.
Endocrine ; 66(2): 288-300, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31368081

RESUMO

PURPOSE: Anaplastic thyroid cancer (ATC) is among the most aggressive and unresectable tumors, presenting a bad prognosis. A better comprehension of the functional and molecular mechanisms behind the aggressiveness of this cancer, as well as new biomarkers for aggressiveness, prognosis, and response to therapy are required. However, owing to their irresectability, ATC tissue is not always accessible. Here we describe the establishment and characterization of a new patient-derived cell line, obtained from an unresectable ATC through fine-needle aspiration cytology (FNAC). METHODS: The morphology, expression of epithelial and thyroid markers, cytogenetic, mutational and gene expression profiles, doubling time, and drug-resistance profile of the new cell line, designated C3948, were investigated using several methodologies: immunostaining, karyotype analysis, comparative genomic hybridization (CGH), fluorescent in situ hybridization (FISH), next-generation sequencing (NGS), Sanger sequencing, gene expression microarrays, cell counting, and IC50 determination. RESULTS: Results indicate that C3948 cell line has a histological phenotype representative of original ATC cells and a completely aberrant karyotype with many chromosomal losses and gains; harbors mutated TP53, STK11, and DIS3L2 genes; presents a gene expression profile similar to C643 ATC commercial cell line, but with some unique alterations; has a doubling time similar to C643; and the IC50 profile for paclitaxel, doxorubicin, and cisplatin is similar to C643, although higher for cisplatin. CONCLUSIONS: These observations are consistent with a typical ATC cell profile, supporting C3948 cell line as a novel preclinical model, and FNAC as a useful approach to better study anaplastic thyroid cancer, including testing of new anticancer therapies.


Assuntos
Carcinoma Anaplásico da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Biópsia por Agulha Fina , Linhagem Celular Tumoral , Hibridização Genômica Comparativa , Citogenética , Perfilação da Expressão Gênica , Humanos , Carcinoma Anaplásico da Tireoide/genética , Neoplasias da Glândula Tireoide/genética
13.
Reproduction ; 158(4): 377-387, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31437815

RESUMO

In recent decades, the prevalence of metabolic diseases has concomitantly increased with a decline on fertility rates and sperm quality. High-fat diets (HFD) are seldom considered part of the problem, but the molecular mechanisms underlying its effects on male fertility remain poorly understood. Herein we postulated that HFD alter sperm quality. We evaluated the effects of switching from a HFD to a normal diet in early adulthood on metabolic disease onset, testicular metabolism and sperm quality. Thirty-six male C57BL6/J mice were divided in: a control group fed with standard chow; a group fed with HFD for 200 days; and a group fed with HFD for 60 days and then with standard chow (HFDt). Biometric data and whole-body metabolism were assessed. Epididymal sperm was studied for concentration, motility, viability and morphology. 1H-NMR metabolomics approach was performed on testicular extracts to trace the metabolic changes. Diet switch reduced body weight and fat mass, preventing metabolic syndrome onset. However, sperm viability, motility and morphology were deteriorated by HFD consumption and not restored by diet switch. HFD induced irreversible changes in pyruvate and glutamate metabolism, ethanol degradation and ammonia recycling in testis. Furthermore, HFDt changed purine and cysteine metabolism, urea cycle, and glutathione content. Overall, HFD caused irreversible changes in testicular metabolism even after switching to normal diet. HFD feeding until early adulthood decreases sperm quality, which cannot be restored by diet switch or weight loss, even when development of metabolic syndrome is avoided.


Assuntos
Dieta Saudável , Dieta Hiperlipídica/efeitos adversos , Síndrome Metabólica/prevenção & controle , Obesidade/complicações , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Testículo/metabolismo , Animais , Masculino , Síndrome Metabólica/etiologia , Síndrome Metabólica/patologia , Camundongos , Camundongos Endogâmicos C57BL
14.
Crit Rev Food Sci Nutr ; 59(16): 2597-2625, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29624433

RESUMO

Methylated xanthines (methylxanthines) are available from a significant number of different botanical species. They are ordinarily included in daily diet, in many extremely common beverages and foods. Caffeine, theophylline and theobromine are the main methylxanthines available from natural sources. The supposedly relatively low toxicity of methylxanthines, combined with the many beneficial effects that have been attributed to these compounds through time, generated a justified attention and a very prolific ground for dedicated scientific reports. Methylxanthines have been widely used as therapeutical tools, in an intriguing range of medicinal scopes. In fact, methylxanthines have been/were medically used as Central Nervous System stimulants, bronchodilators, coronary dilators, diuretics and anti-cancer adjuvant treatments. Other than these applications, methylxanthines have also been hinted to hold other beneficial health effects, namely regarding neurodegenerative diseases, cardioprotection, diabetes and fertility. However, it seems now consensual that toxicity concerns related to methylxanthine consumption and/or therapeutic use should not be dismissed. Taking all the knowledge and expectations on the potential of methylxanthines into account, we propose a systematic look at the past and future of methylxanthine pharmacologic applications, discussing all the promise and anticipating possible constraints. Anyways, methylxanthines will still substantiate considerable meaningful research and discussion for years to come.


Assuntos
Xantinas/história , Xantinas/uso terapêutico , História do Século XX , História do Século XXI , Humanos , Estudos Retrospectivos , Xantinas/química
15.
Curr Neuropharmacol ; 17(7): 590-613, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30081787

RESUMO

Diabetes Mellitus (DM) and Alzheimer's disease (AD) are two prevalent diseases in modern societies, which are caused mainly by current lifestyle, aging and genetic alterations. It has already been demonstrated that these two diseases are associated, since individuals suffering from DM are prone to develop AD. Conversely, it is also known that individuals with AD are more susceptible to DM, namely type 2 diabetes (T2DM). Therefore, these two pathologies, although completely different in terms of symptomatology, end up sharing several mechanisms at the molecular level, with the most obvious being the increase of oxidative stress and inflammation. Polyphenols are natural compounds widely spread in fruits and vegetables whose dietary intake has been considered inversely proportional to the incidence of DM and AD. So, it is believed that this group of phytochemicals may have preventive and therapeutic potential, not only by reducing the risk and delaying the development of these pathologies, but also by improving brain's metabolic profile and cognitive function. The aim of this review is to understand the extent to which DM and AD are related pathologies, the degree of similarity and the relationship between them, to detail the molecular mechanisms by which polyphenols may exert a protective effect, such as antioxidant and anti-inflammatory effects, and highlight possible advantages of their use as common preventive and therapeutic alternatives.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antioxidantes/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Polifenóis/farmacologia , Animais , Humanos , Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos
16.
Toxicol In Vitro ; 53: 114-120, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30098389

RESUMO

Caffeine is one of the most worldwide consumed methylxanthines. It is well-known for its thermogenic and cell metabolism modulating effects. Based on methylxanthines' chemical structure, 8-(3-phenylpropyl)-1,3,7-triethylxanthine (PTX) is a novel adenosine antagonist with higher receptor affinity than caffeine. Therefore, we hypothesized that PTX metabolic effects could be stronger than those of caffeine. For that purpose, murine 3T3-L1 cells were cultured in the presence of increasing doses of PTX or caffeine (0.1, 1, 10 and 100 µM) for 24 h. Cytotoxicity was evaluated by reduction of tetrazolium salt (MTT) and lactate dehydrogenase (LDH) release. Cell metabolites released to the culture medium were identified and quantified by proton nuclear magnetic resonance (1H NMR). Cellular oxidative profile was also evaluated. Our results showed that PTX displayed no signs of cytotoxicity at all studied concentrations. When compared with caffeine, PTX increased glucose, pyruvate, and glutamine consumption, as well as lactate, alanine, and acetate production. Additionally, PTX decreased protein oxidation, thus protecting against oxidative stress-induced damage. These results illustrate that PTX is a stronger and less cytotoxic caffeine substitute with potential applications as metabolic modulator and a good candidate for novel drug design.


Assuntos
Xantinas/toxicidade , Células 3T3-L1 , Animais , Sobrevivência Celular/efeitos dos fármacos , Glicólise/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Camundongos , Oxirredução
17.
J Clin Endocrinol Metab ; 103(8): 2879-2888, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29846619

RESUMO

Context: Autosomal dominant hypocalcemia type 1 (ADH1) is caused by heterozygous activating mutations in the calcium-sensing receptor gene (CASR). Whether polymorphisms that are benign in the heterozygous state pathologically alter receptor function in the homozygous state is unknown. Objective: To identify the genetic defect in an adolescent female with a history of surgery for bilateral cataracts and seizures. The patient has hypocalcemia, hyperphosphatemia, and low serum PTH level. The parents of the proband are healthy. Methods: Mutation testing of PTH, GNA11, GCM2, and CASR was done on leukocyte DNA of the proband. Functional analysis in transfected cells was conducted on the gene variant identified. Public single nucleotide polymorphism (SNP) databases were searched for the presence of the variant allele. Results: No mutations were identified in PTH, GNA11, and GCM2 in the proband. However, a germline homozygous variant (c.1631G>A; p.R544Q) in exon 6 of the CASR was identified. Both parents are heterozygous for the variant. The variant allele frequency was near 0.1% in SNP databases. By in vitro functional analysis, the variant was significantly more potent in stimulating both the Ca2+i and MAPK signaling pathways than wild type when transfected alone (P < 0.05) but not when transfected together with wild type. The overactivity of the mutant CaSR is due to loss of a critical structural cation-π interaction. Conclusions: The patient's hypoparathyroidism is due to homozygosity of a variant in the CASR that normally has weak or no phenotypic expression in heterozygosity. Although rare, this has important implications for genetic counseling and clinical management.


Assuntos
Hipocalcemia/genética , Hipoparatireoidismo/genética , Polimorfismo de Nucleotídeo Único , Receptores de Detecção de Cálcio/genética , Substituição de Aminoácidos , Arginina/genética , Feminino , Ácido Glutâmico/genética , Homozigoto , Humanos , Hipocalcemia/complicações , Hipoparatireoidismo/complicações , Adulto Jovem
18.
Eur J Med Genet ; 61(5): 294-299, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29292210

RESUMO

Germline mutations in the WT1 gene have been identified in some families with Wilms tumor. Recently, the CTR9 gene was found to be mutated in three families with Wilms tumor, thus representing a novel predisposition gene for this disease. We identified a family with a history of Wilms tumor characterized by three affected siblings, one of them presenting an aggressive bilateral tumor. Here we investigated the involvement of WT1 and CTR9 genes in this family with Wilms tumor. The involvement of WT1 was first evaluated by Next generation sequencing in leukocytes DNA from one affected family member. Subsequently, the CTR9 gene was analyzed by Sanger sequencing in DNA and RNA from patients' leukocytes and/or tumor. No mutations were detected in WT1. However, we identified a novel CTR9 germline variant, located in a consensus splice acceptor site, which was found to segregate with Wilms tumor in this family. We found that this variant leads to the skipping of the entire exon 9 in the mRNA, which is predicted to encode a truncated CTR9 protein, strongly suggesting that it is pathogenic. Additionally, we also detected loss of heterozygosity in the index case tumor, which is consistent with CTR9 being a tumor suppressor gene, confirming also its contribution to familial Wilms tumor etiology. The identification of a novel CTR9 germline mutation will improve the present knowledge on the molecular basis of familial Wilms tumor. Importantly, it will help in the genetic counselling and may also lead to earlier diagnosis in other family members and future generations.


Assuntos
Mutação em Linhagem Germinativa , Proteínas Nucleares/genética , Fosfoproteínas/genética , Tumor de Wilms/genética , Pré-Escolar , Feminino , Humanos , Lactente , Perda de Heterozigosidade , Masculino , Linhagem , Sítios de Splice de RNA , Fatores de Transcrição , Tumor de Wilms/patologia
19.
Clin Endocrinol (Oxf) ; 87(4): 394-399, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28502101

RESUMO

OBJECTIVE: The genes causing familial nonmedullary thyroid carcinoma (FNMTC) identified to date are only involved in a small fraction of the families. Recently, somatic mutations in TERT promoter region and in EIF1AX gene were reported in thyroid tumours of undefined familial status. The aim of this study was to investigate the role of TERT and EIF1AX mutations in familial thyroid tumours. DESIGN: The promoter region of TERT was sequenced in leucocyte DNA of the probands from 75 FNMTC families. In thyroid tumours from 54 familial cases, we assessed somatic TERT promoter, RAS and BRAF hotspot mutations, and the whole EIF1AX gene. RESULTS: No potentially pathogenic germline variants were identified in TERT in the 75 FNMTC families' probands. In the 54 carcinomas, we identified five cases (9%) with hotspot somatic TERT promoter mutations. BRAF mutations were found in 41% of the tumours. All TERT-positive samples were also positive for BRAF p.Val600Glu, and this co-occurrence was found to be statistically significant (P=.008). RAS mutations were detected in four tumours wild-type for TERT (7%). Evaluation of tumour mutation data together with the patients' clinicopathological features revealed a significant correlation between TERT plus BRAF mutations and advanced tumour stage (T4) (P=.020). No mutations were identified in EIF1AX. CONCLUSIONS: The results of this study suggest that TERT promoter and EIF1AX mutations are not frequently involved in FNMTC aetiology. However, we show for the first time that TERT alterations are associated with familial thyroid tumour progression. Our data also suggest that TERT mutations are more often found in concomitance with BRAF mutations in advanced stages of FNMTC.


Assuntos
Proteínas Proto-Oncogênicas B-raf/genética , Telomerase/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Carcinoma Papilar/genética , Fator de Iniciação 1 em Eucariotos/genética , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Câncer Papilífero da Tireoide
20.
Food Res Int ; 95: 91-100, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28395830

RESUMO

Cherries are one of the most appreciated summer fruits due to their attractive colour, sweet taste, high water content, low level of calories and composition in bioactive compounds which, in turn, are important to prevent some pathologies like diabetes, cardiovascular diseases and cancer. In this work we evaluated the phenolic profile and biological potential of 5 varieties of sweet cherries from Fundão region (Portugal) (Saco, Sweetheart, Satin, Maring and Hedelfinger). A total of 23 phenolic compounds were identified by LC-DAD and distributed by the several classes: 6 anthocyanins, 1 hydroxybenzoic acid, 8 hydroxycinnamic acids, 3 flavan-3-ols and 5 flavonols. Maring revealed higher contents in anthocyanins, while Hedelfinger was the richest in non-coloured phenolics. The antioxidant capacity was evaluated against DPPH and nitric oxide radicals. Hedelfinger was the most active against DPPH• (IC50=12.1µg/mL) and Maring against nitric oxide (IC50=140.9µg/mL). Afterwards, antidiabetic capacity was evaluated through the inhibition of α-glucosidase activity, pointing Hedelfinger as the most active (IC50=10.3µg/mL). The capacity of Saco extracts to inhibit the hemoglobin oxidation and the hemolysis of human erythrocytes was also evaluated. Both assays revealed a concentration-dependent inhibitory effect (IC50=38.6µg/mL and IC50=73.0µg/mL, respectively). The results obtained in this study allow us to conclude that sweet cherries possess a great biological potential, and further investigation should be done to promote commercialization and encourage its use in food supplements and in new pharmaceutical and nutraceutical applications.


Assuntos
Eritrócitos/efeitos dos fármacos , Frutas/química , Hipoglicemiantes/farmacologia , Prunus avium/química , Antocianinas/farmacologia , Antioxidantes/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Portugal , Substâncias Protetoras/farmacologia
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