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1.
Mol Cell Proteomics ; 15(11): 3361-3372, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27694331

RESUMO

N-terminal acetylation (Nt-acetylation) by N-terminal acetyltransferases (NATs) is one of the most common protein modifications in eukaryotes. The NatC complex represents one of three major NATs of which the substrate profile remains largely unexplored. Here, we defined the in vivo human NatC Nt-acetylome on a proteome-wide scale by combining knockdown of its catalytic subunit Naa30 with positional proteomics. We identified 46 human NatC substrates, expanding our current knowledge on the substrate repertoire of NatC which now includes proteins harboring Met-Leu, Met-Ile, Met-Phe, Met-Trp, Met-Val, Met-Met, Met-His and Met-Lys N termini. Upon Naa30 depletion the expression levels of several organellar proteins were found reduced, in particular mitochondrial proteins, some of which were found to be NatC substrates. Interestingly, knockdown of Naa30 induced the loss of mitochondrial membrane potential and fragmentation of mitochondria. In conclusion, NatC Nt-acetylates a large variety of proteins and is essential for mitochondrial integrity and function.


Assuntos
Proteínas Mitocondriais/metabolismo , Acetiltransferase N-Terminal C/genética , Acetiltransferase N-Terminal C/metabolismo , Proteômica/métodos , Acetilação , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Ligação Proteica , Mapas de Interação de Proteínas , Especificidade por Substrato
2.
Acta Radiol ; 57(10): 1193-200, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26163534

RESUMO

BACKGROUND: Positron emission tomography (PET) with fluor-18-deoxy-glucose (FDG) is widely used for diagnosing recurrent or metastatic disease in patients with differentiated thyroid cancer (DTC). PURPOSE: To assess the diagnostic accuracy of FDG-PET for DTC in patients after ablative therapy. MATERIAL AND METHODS: A systematic search was conducted in Medline/PubMed, EMBASE, Cochrane Library, Web of Science, and Open Grey looking for all English-language original articles on the performance of FDG-PET in series of at least 20 patients with DTC having undergone ablative therapy including total thyroidectomy. Diagnostic performance measures were pooled using Reitsma's bivariate model. RESULTS: Thirty-four publications between 1996 and 2014 met the inclusion criteria. Pooled sensitivity and specificity were 79.4% (95% confidence interval [CI], 73.9-84.1) and 79.4% (95% CI, 71.2-85.4), respectively, with an area under the curve of 0.858. CONCLUSION: F18-FDG-PET is a useful method for detecting recurrent DTC in patients having undergone ablative therapy.


Assuntos
Fluordesoxiglucose F18 , Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Humanos
3.
Acta Radiol ; 56(11): 1350-60, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25770086

RESUMO

BACKGROUND: Positron emission tomography (PET) using fluor-18-deoxyglucose (18F-FDG) with or without computed tomography (CT) is generally accepted as the most sensitive imaging modality for diagnosing recurrent differentiated thyroid cancer (DTC) in patients with negative whole body scintigraphy with iodine-131 (I-131). PURPOSE: To assess the potential incremental value of ultrasound (US) over 18F-FDG-PET-CT. MATERIAL AND METHODS: Fifty-one consecutive patients with suspected recurrent DTC were prospectively evaluated using the following multimodal imaging protocol: (i) US before PET (pre-US) with or without fine needle biopsy (FNB) of suspicious lesions; (ii) single photon emission computed tomography (≥3 GBq I-131) with co-registered CT (SPECT-CT); (iii) 18F-FDG-PET with co-registered contrast-enhanced CT of the neck; (iv) US in correlation with the other imaging modalities (post-US). Postoperative histology, FNB, and long-term follow-up (median, 2.8 years) were taken as composite gold standard. RESULTS: Fifty-eight malignant lesions were identified in 34 patients. Forty lesions were located in the neck or upper mediastinum. On receiver operating characteristics (ROC) analysis, 18F-FDG-PET had a limited lesion-based specificity of 59% at a set sensitivity of 90%. Pre-US had poor sensitivity and specificity of 52% and 53%, respectively, increasing to 85% and 94% on post-US, with knowledge of the PET/CT findings (P < 0.05 vs. PET and pre-US). Multimodal imaging changed therapy in 15 out of 51 patients (30%). CONCLUSION: In patients with suspected recurrent DTC, supplemental targeted US in addition to 18F-FDG-PET-CT increases specificity while maintainin sensitivity, as non-malignant FDG uptake in cervical lesions can be confirmed.


Assuntos
Imagem Multimodal , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adulto , Idoso , Biópsia por Agulha Fina , Feminino , Fluordesoxiglucose F18 , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tomografia Computadorizada por Raios X , Ultrassonografia
4.
Ann Surg ; 259(4): 800-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23979292

RESUMO

OBJECTIVE: This investigation aimed at exploring the suitability of nonendocrine manifestations preceding medullary thyroid cancer (MTC) for early diagnosis of multiple endocrine neoplasia type 2B (MEN 2B). BACKGROUND: MEN 2B patients, running a high risk of metastatic MTC, must be diagnosed early for biochemical cure. METHODS: Forty-four MEN 2B patients carrying inherited (3 patients) and de novo (41 patients) M918T RET mutations were examined for signs and symptoms prompting MEN 2B. RESULTS: All 3 patients with inherited mutations were diagnosed before the age of 1 year and cured of their C-cell disease. Among 41 patients with de novo mutations, MEN 2B was diagnosed in 12 patients after recognition of nonendocrine manifestations [intestinal ganglioneuromatosis (6 patients), oral symptoms (5 patients), ocular ("tearless crying") (4 patients), and skeletal stigmata (1 patient) alone or concomitantly]. In the remaining 29 patients with de novo mutations, the diagnosis of MEN 2B was triggered by symptomatic MTC (28 patients) or pheochromocytoma (1 patient). The former patients, being significantly (P < 0.001) younger (means of 5.3 vs 17.6 years) and having lower calcitonin levels (means of 115 vs 25,519 pg/mL), smaller tumors (67% vs 0% were ≤10 mm) and less often extrathyroidal extension (0% vs 81%), lymph node (42% vs 100%), and distant metastases (8% vs 79%), were biochemically cured more often (58% vs 0%). CONCLUSIONS: MTC is curable in patients with de novo mutations when nonendocrine MEN 2B components are quickly appreciated and surgical intervention is performed before patients turn 4 years old.


Assuntos
Biomarcadores Tumorais/genética , Neoplasia Endócrina Múltipla Tipo 2b/diagnóstico , Proteínas Proto-Oncogênicas c-ret/genética , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Adolescente , Neoplasias das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/etiologia , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/cirurgia , Adulto , Carcinoma Neuroendócrino , Criança , Pré-Escolar , Feminino , Seguimentos , Marcadores Genéticos , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Neoplasia Endócrina Múltipla Tipo 2b/complicações , Neoplasia Endócrina Múltipla Tipo 2b/genética , Neoplasia Endócrina Múltipla Tipo 2b/cirurgia , Mutação , Esvaziamento Cervical , Feocromocitoma/diagnóstico , Feocromocitoma/etiologia , Feocromocitoma/genética , Feocromocitoma/cirurgia , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/genética , Resultado do Tratamento , Adulto Jovem
5.
Langenbecks Arch Surg ; 398(6): 869-74, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23778974

RESUMO

BACKGROUND: Primary aldosteronism (PA) is a frequent cause (about 10 %) of hypertension. Some cases of PA were recently found to be caused by mutations in the potassium channel KCNJ5. Our objective was to determine the mutation status of KCNJ5 and seven additional candidate genes for tumorigenesis: YY1, FZD4, ARHGAP9, ZFP37, KDM5C, LRP1B, and PDE9A and, furthermore, the surgical outcome of PA patients who underwent surgery in Western Norway. METHODS: Twenty-eight consecutive patients with aldosterone-producing adrenal tumors (20 patients with single adenoma, 8 patients with unilateral multiple adenomas or hyperplasia) who underwent surgery were included in this study. All patients were operated on by uncomplicated laparoscopic total adrenalectomy. Genomic DNA was isolated from tumor and non-tumor adrenocortical tissue, and DNA sequencing revealed the mutation status. RESULTS: Ten out of 28 (36 %) patients with PA displayed tumor mutations in KCNJ5 (p. G151R and L168R) while none were found in the corresponding non-tumor samples. No mutations were found in the other seven candidate genes screened. The presence of KCNJ5 mutations was associated with lower blood pressure and a higher chance for cure by surgery when compared to patients harboring the KCNJ5 wild type. CONCLUSIONS: KCNJ5 mutations are associated with a better surgical outcome. Preoperative identification of the mutation status might have impact on surgical strategy (total vs. subtotal adrenalectomy).


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/cirurgia , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Regulação Neoplásica da Expressão Gênica , Hiperaldosteronismo/genética , Hiperaldosteronismo/cirurgia , Neoplasias das Glândulas Suprarrenais/fisiopatologia , Adrenalectomia/efeitos adversos , Adrenalectomia/métodos , Adulto , Estudos de Coortes , Feminino , Seguimentos , Predisposição Genética para Doença , Humanos , Hiperaldosteronismo/fisiopatologia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Mutação , Noruega , Complicações Pós-Operatórias/genética , Complicações Pós-Operatórias/fisiopatologia , Estudos Retrospectivos , Medição de Risco , Resultado do Tratamento
6.
Proc Natl Acad Sci U S A ; 106(20): 8157-62, 2009 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-19420222

RESUMO

N(alpha)-terminal acetylation is one of the most common protein modifications in eukaryotes. The COmbined FRActional DIagonal Chromatography (COFRADIC) proteomics technology that can be specifically used to isolate N-terminal peptides was used to determine the N-terminal acetylation status of 742 human and 379 yeast protein N termini, representing the largest eukaryotic dataset of N-terminal acetylation. The major N-terminal acetyltransferase (NAT), NatA, acts on subclasses of proteins with Ser-, Ala-, Thr-, Gly-, Cys- and Val- N termini. NatA is composed of subunits encoded by yARD1 and yNAT1 in yeast and hARD1 and hNAT1 in humans. A yeast ard1-Delta nat1-Delta strain was phenotypically complemented by hARD1 hNAT1, suggesting that yNatA and hNatA are similar. However, heterologous combinations, hARD1 yNAT1 and yARD1 hNAT1, were not functional in yeast, suggesting significant structural subunit differences between the species. Proteomics of a yeast ard1-Delta nat1-Delta strain expressing hNatA demonstrated that hNatA acts on nearly the same set of yeast proteins as yNatA, further revealing that NatA from humans and yeast have identical or nearly identical specificities. Nevertheless, all NatA substrates in yeast were only partially N-acetylated, whereas the corresponding NatA substrates in HeLa cells were mainly completely N-acetylated. Overall, we observed a higher proportion of N-terminally acetylated proteins in humans (84%) as compared with yeast (57%). N-acetylation occurred on approximately one-half of the human proteins with Met-Lys- termini, but did not occur on yeast proteins with such termini. Thus, although we revealed different N-acetylation patterns in yeast and humans, the major NAT, NatA, acetylates the same substrates in both species.


Assuntos
Acetiltransferases/genética , Evolução Molecular , Proteínas Fúngicas/genética , Proteômica/métodos , Acetilação , Arilamina N-Acetiltransferase/genética , Células HeLa , Humanos , Isoenzimas/genética , Acetiltransferase N-Terminal A , Acetiltransferase N-Terminal E , Subunidades Proteicas , Especificidade por Substrato
7.
Int J Cancer ; 127(12): 2777-89, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21351257

RESUMO

The human protein N(α)-terminal acetyltransferase A complex (hNatA), composed of the catalytic hNaa10p (hArd1) and auxiliary hNaa15p (hNat1/NATH/Tubedown) subunits, was reported to be important for cell survival and growth of various types of cancer. However, little is known about the mechanisms mediating growth inhibition and apoptosis following loss of hNatA function. Here, we have screened 11 different thyroid cell lines for hNAA10 RNAi phenotypes and observed mostly growth inhibition, which was independent of TP53 functional status and developed by several different mechanisms involving (i) downregulation of cyclin D1, (ii) increase in p27/Kip1 and (iii) inactivation of Rb/E2F pathway. hNatA depletion in aggressive thyroid cancer cell lines (8305C, CAL-62 and FTC-133) with mutated TP53 increased sensitivity to drug-induced cytotoxicity, but in a cell type specific manner: 8305C (TRAIL), CAL-62 (daunorubicin) and FTC-133 (troglitazone). Cells harboring wild-type TP53 were also prone to apoptosis via the p53 pathway after hNatA downregulation. Importantly, in hNatA-depleted cells DNA-damage signaling was activated in the absence of exogenous DNA damage independent on TP53 status. Our findings indicate that several mechanisms of growth inhibition and apoptosis may be induced by hNatA knockdown and that hNatA knockdown could be exploited for use in combinatorial chemotherapy.


Assuntos
Apoptose , Arilamina N-Acetiltransferase/genética , Isoenzimas/genética , Interferência de RNA , Neoplasias da Glândula Tireoide/enzimologia , Neoplasias da Glândula Tireoide/patologia , Proteína Supressora de Tumor p53/metabolismo , Western Blotting , Carcinoma/enzimologia , Carcinoma/genética , Carcinoma/patologia , Carcinoma Papilar/enzimologia , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Ciclo Celular , Diferenciação Celular , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Humanos , Técnicas Imunoenzimáticas , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias da Glândula Tireoide/genética , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética
8.
BMC Cancer ; 10: 313, 2010 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-20565970

RESUMO

BACKGROUND: The cytochrome P450 (CYP) enzymes 2C19, 2D6, and 3A5 are responsible for converting the selective estrogen receptor modulator (SERM), tamoxifen to its active metabolites 4-hydroxy-tamoxifen (4OHtam) and 4-hydroxy-N-demethyltamoxifen (4OHNDtam, endoxifen). Inter-individual variations of the activity of these enzymes due to polymorphisms may be predictors of outcome of breast cancer patients during tamoxifen treatment. Since tamoxifen and estrogens are both partly metabolized by these enzymes we hypothesize that a correlation between serum tamoxifen and estrogen levels exists, which in turn may interact with tamoxifen on treatment outcome. Here we examined relationships between the serum levels of tamoxifen, estrogens, follicle-stimulating hormone (FSH), and also determined the genotypes of CYP2C19, 2D6, 3A5, and SULT1A1 in 90 postmenopausal breast cancer patients. METHODS: Tamoxifen and its metabolites were measured by liquid chromatography-tandem mass spectrometry. Estrogen and FSH levels were determined using a sensitive radio- and chemiluminescent immunoassay, respectively. RESULTS: We observed significant correlations between the serum concentrations of tamoxifen, N-dedimethyltamoxifen, and tamoxifen-N-oxide and estrogens (p < 0.05). The genotype predicted CYP2C19 activity influenced the levels of both tamoxifen metabolites and E1. CONCLUSIONS: We have shown an association between tamoxifen and its metabolites and estrogen serum levels. An impact of CYP2C19 predicted activity on tamoxifen, as well as estrogen kinetics may partly explain the observed association between tamoxifen and its metabolites and estrogen serum levels. Since the role of estrogen levels during tamoxifen therapy is still a matter of debate further prospective studies to examine the effect of tamoxifen and estrogen kinetics on treatment outcome are warranted.


Assuntos
Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Estrogênios/sangue , Hormônio Foliculoestimulante/sangue , Tamoxifeno/sangue , Tamoxifeno/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/sangue , Antineoplásicos Hormonais/uso terapêutico , Hidrocarboneto de Aril Hidroxilases/genética , Neoplasias da Mama/genética , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP3A/genética , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Genético/genética , Pós-Menopausa , Resultado do Tratamento
9.
Langenbecks Arch Surg ; 395(7): 851-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20683623

RESUMO

PURPOSE: Approximately 5% of differentiated thyroid carcinomas are of familial origin. These familial nonmedullary thyroid carcinomas (FNMTC) have an increased risk of multifocal disease and lymph node involvement. Consequently, higher recurrence rates and decreased disease-specific survival rates are described. The best surgical approach is discussed controversially. PATIENTS AND METHODS: A survey among the international members of the German Society of Endocrine Surgeons revealed 20 families with two or more first-degree relatives with FNMTC. The mean age of the 41 patients (30 female, 11 male) with FNMTC was 40.6 years (18-73 years). RESULTS: Total thyroidectomy was performed in 31 of 41 patients (76%). Ninety-five percent of the tumors were papillary carcinomas. Two of 41 patients had follicular carcinomas. Ten patients (24%) with papillary carcinomas were diagnosed with Hashimoto's thyroiditis. The mean tumor size was 1.45 cm. FNMTC was multifocal in 12 patients (29%). A systematic lymph node dissection was performed in 21 of 41 patients (51%). Lymph nodes metastases were found in seven of these 21 patients. Twenty-eight of the patients (68%) underwent postoperative radioiodine ablation. After a mean follow-up of 7.2 years, 39 patients (95%) were disease free. One patient developed local recurrence and lung metastases, 10 and 25 years, respectively, after initial diagnosis. Another patient died 2 years postoperatively from advanced metastatic disease. CONCLUSIONS: FNMTC is associated with an early onset of small, mostly papillary thyroid carcinomas and an increased risk of multifocality and lymph node involvement. Total thyroidectomy and systematic neck dissection are recommended together with radioiodine ablation. Screening for first-degree relatives should start at age 18 years.


Assuntos
Linfonodos/patologia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/mortalidade , Adenocarcinoma Folicular/patologia , Adenocarcinoma Folicular/secundário , Adenocarcinoma Folicular/cirurgia , Adenocarcinoma Papilar/genética , Adenocarcinoma Papilar/mortalidade , Adenocarcinoma Papilar/patologia , Adenocarcinoma Papilar/secundário , Adenocarcinoma Papilar/cirurgia , Adolescente , Adulto , Idoso , Biópsia por Agulha , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Predisposição Genética para Doença , Alemanha , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/secundário , Excisão de Linfonodo/métodos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical/métodos , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Linhagem , Prognóstico , Medição de Risco , Análise de Sobrevida , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/mortalidade , Resultado do Tratamento , Adulto Jovem
10.
Tidsskr Nor Laegeforen ; 130(7): 724-8, 2010 Apr 08.
Artigo em Norueguês | MEDLINE | ID: mdl-20379332

RESUMO

BACKGROUND: We wanted to check if our routines for diagnosing and treating primary operable breast cancer and ductal carcinoma in situ were concordant with national guidelines and quality standards. MATERIAL AND METHODS: Data were retrospectively collected from medical journals for all relevant patients operated at Alesund Hospital, Norway from 1.11.02 to 1.05.08. RESULTS: 487 breasts were operated in 478 patients. A triple-diagnostic approach (mammography/ultrasound, clinical examination and biopsy) was used in 98 % of patients and ultrasound-guided core-needle-biopsy in 86 %. For 82 % of patients one visit in an out-patient-department was enough to conclude with a malignant diagnosis. A sentinel node biopsy was taken for 378 of 457 (83 %) patients operated in the axilla; a sentinel node was found in 93 % of them. Three (median) sentinel nodes were removed (spread in the range 1 - 12). 51 % of patients had breast-conserving surgery. From diagnosis of cancer to completion of all surgical procedures, 57 patients (12 %) had two operations, three (0.6 %) had three operations (in the breast and axilla), and 89 % of patients had completed all surgery within three weeks.13 % of patients had postoperative complications. After axillary lymph-node dissection, 20 % of patients had lymph-oedema/shoulder/arm pain. Three patients had ipsilateral relapse in the breast or thoracic wall. None had axillary relapse after sentinel-node biopsy. The median observation time was 26 months (0 - 66 months). INTERPRETATION: The results of diagnosis and treatment in our hospital are in good accordance with our national guidelines and quality standards.


Assuntos
Neoplasias da Mama , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Feminino , Fidelidade a Diretrizes , Humanos , Excisão de Linfonodo , Mamografia , Mastectomia Segmentar , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Noruega , Complicações Pós-Operatórias/etiologia , Guias de Prática Clínica como Assunto , Garantia da Qualidade dos Cuidados de Saúde , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela
11.
Breast Cancer Res Treat ; 113(3): 519-28, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18330697

RESUMO

Apolipoprotein D (ApoD) is a lipocalin involved in various cellular processes, including cytoprotection. We retrospectively evaluated its prognostic impact in 272 women (median age 63 (range 21-89) years, with operable breast cancer (Stage I or IIa) treated according to national guidelines, stratified by age and menopausal status, with a median long-term follow-up of 12 years. ApoD, estrogen receptor-alpha (ERalpha), and progesterone receptor (PR) positivity were determined by quantitative immunohistochemistry in tissue microarrays taken from the invasive front of the tumors and in whole tumor sections. ApoD was expressed in 50% of the tumors. Diffuse nuclear and cytoplasmic (ApoD(CN)), but not granular cytoplasmic ApoD expression in the invasive front was a detrimental factor for elderly patients over 70 years of age, (n = 83), but not for younger and pre-menopausal patients. ApoD(CN )expression correlated with lymph node metastases (P = 0.04). Moreover, a correlation between ApoD(CN )localization and age over 70 years was observed (P = 0.03). In the elderly, ApoD(CN) positive tumors had both a significantly shorter relapse-free survival (all locations) (P = 0.02) and a decreased breast cancer-specific survival (P < 0.0001). Moreover, the prognostic importance of ApoD was dose dependent (P = 0.002) Multivariate analysis confirmed the prognostic value of ApoD(CN). When the elderly patients were stratified by nodal status, ApoD showed prognostic importance only in the node positive patients (n = 30) (HR = 9.6; 95% CI = 2.3-40.4). The potential relevance of ApoD in this increasingly frequent group of breast cancer patients should be further explored.


Assuntos
Apolipoproteínas D/biossíntese , Neoplasias da Mama/metabolismo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Análise Serial de Proteínas , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
12.
BMC Biochem ; 10: 15, 2009 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-19480662

RESUMO

BACKGROUND: Protein acetylation is among the most common protein modifications. The two major types are post-translational Nepsilon-lysine acetylation catalyzed by KATs (Lysine acetyltransferases, previously named HATs (histone acetyltransferases) and co-translational Nalpha-terminal acetylation catalyzed by NATs (N-terminal acetyltransferases). The major NAT complex in yeast, NatA, is composed of the catalytic subunit Naa10p (N alpha acetyltransferase 10 protein) (Ard1p) and the auxiliary subunit Naa15p (Nat1p). The NatA complex potentially acetylates Ser-, Ala-, Thr-, Gly-, Val- and Cys- N-termini after Met-cleavage. In humans, the homologues hNaa15p (hNat1) and hNaa10p (hArd1) were demonstrated to form a stable ribosome associated NAT complex acetylating NatA type N-termini in vitro and in vivo. RESULTS: We here describe a novel human protein, hNaa16p (hNat2), with 70% sequence identity to hNaa15p (hNat1). The gene encoding hNaa16p originates from an early vertebrate duplication event from the common ancestor of hNAA15 and hNAA16. Immunoprecipitation coupled to mass spectrometry identified both endogenous hNaa15p and hNaa16p as distinct interaction partners of hNaa10p in HEK293 cells, thus demonstrating the presence of both hNaa15p-hNaa10p and hNaa16p-hNaa10p complexes. The hNaa16p-hNaa10p complex acetylates NatA type N-termini in vitro. hNaa16p is ribosome associated, supporting its potential role in cotranslational Nalpha-terminal acetylation. hNAA16 is expressed in a variety of human cell lines, but is generally less abundant as compared to hNAA15. Specific knockdown of hNAA16 induces cell death, suggesting an essential role for hNaa16p in human cells. CONCLUSION: At least two distinct NatA protein Nalpha-terminal acetyltransferases coexist in human cells potentially creating a more complex and flexible system for Nalpha-terminal acetylation as compared to lower eukaryotes.


Assuntos
Acetiltransferases/metabolismo , Arilamina N-Acetiltransferase/fisiologia , Complexos Multienzimáticos/fisiologia , Acetilação , Sequência de Aminoácidos , Arilamina N-Acetiltransferase/metabolismo , Morte Celular , Linhagem Celular Tumoral , Evolução Molecular , Humanos , Isoenzimas/metabolismo , Dados de Sequência Molecular , Acetiltransferase N-Terminal E , Acetiltransferases N-Terminal , Peptídeos/metabolismo , Filogenia , Processamento de Proteína Pós-Traducional , Ribossomos/metabolismo , Alinhamento de Sequência
13.
Acta Oncol ; 48(4): 514-21, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19107621

RESUMO

BACKGROUND: Estrogen receptor-alpha (ERalpha) is an important prognostic and predictive marker in breast cancer. ERalpha signaling normally down-regulates expression of Apolipoprotein D (ApoD), a lipocalin that binds, transports or chelates lipophilic ligands, including tamoxifen (TAM). Hence, the co-expression of ApoD may therefore identify clinical relevant subgroups of ERalpha positive breast cancer patients. MATERIAL AND METHODS: ApoD, ERalpha, and progesterone receptor (PR) protein expressions were determined by immunohistochemistry (IHC) in primary tumors of 290 patients with operable breast cancer. The median follow-up was 12 years. Patients were stratified according to age, nodal stage and the expression of ERalpha and the combined cytoplasm and nuclear staining of ApoD (ApoD(CN)). RESULTS: In elderly women (> or =70 years) (n = 76), ApoD(CN) expression identified different prognostic subgroups in ERalpha positive patients (Trend: p < 0.0001). Multivariate analysis in this age group (n = 72), showed that the ERalpha-positive /ApoD(CN)-negative subgroup had a better breast cancer specific survival (BCSS) compared with the ERalpha-positive/ApoD(CN)-positive group (hazard ratio (HR) = 4.3; 95% CI = 1.6-11.9; p = 0.005). This difference was predominantly seen in the node positive patients (n = 30) (HR = 10.5; 95% CI = 2.3-47.6; p = 0.002). In a subset of postmenopausal ERalpha-positive/node positive patients (n = 60) previously enrolled in a trial on 2 year adjuvant TAM 20 mg vs. placebo, a better BCSS was observed in ApoD(CN) negative patients compared to placebo (p = 0.02). In ApoD(CN) positive patients, adjuvant TAM did not provide any survival benefit. DISCUSSION: ERalpha and ApoD(CN) co-expression seems to be of prognostic importance in node positive elderly patients with operable breast cancer. In addition, we hypothesize that ApoD(CN) expression may be a novel marker and/or mechanism of TAM resistance in postmenopausal node positive patients. Thus, when targeting the ERalpha pathway in these patients, the ApoD status of the tumor may be of clinical relevance.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Apolipoproteínas D/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Receptor alfa de Estrogênio/metabolismo , Linfonodos/patologia , Pós-Menopausa , Tamoxifeno/uso terapêutico , Fatores Etários , Idoso , Análise de Variância , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Pessoa de Meia-Idade , Razão de Chances , Prognóstico
14.
Biochem J ; 415(2): 325-31, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18570629

RESUMO

Protein N(alpha)-terminal acetylation is a conserved and widespread protein modification in eukaryotes. Several studies have linked it to normal cell function and cancer development, but nevertheless, little is known about its biological function. In yeast, protein N(alpha)-terminal acetylation is performed by the N-acetyltransferase complexes NatA, NatB and NatC. In humans, only the NatA complex has been identified and characterized. In the present study we present the components of hNatB (human NatB complex). It consists of the Nat3p homologue hNAT3 (human N-acetyltransferase 3) and the Mdm20p homologue hMDM20 (human mitochondrial distribution and morphology 20). They form a stable complex and in vitro display sequence-specific N(alpha)-acetyltransferase activity on a peptide with the N-terminus Met-Asp-. hNAT3 and hMDM20 co-sediment with ribosomal pellets, thus supporting a model where hNatB acts co-translationally on nascent polypeptides. Specific knockdown of hNAT3 and hMDM20 disrupts normal cell-cycle progression, and induces growth inhibition in HeLa cells and the thyroid cancer cell line CAL-62. hNAT3 knockdown results in an increase in G(0)/G(1)-phase cells, whereas hMDM20 knockdown decreased the fraction of cells in G(0)/G(1)-phase and increased the fraction of cells in the sub-G(0)/G(1)-phase. In summary, we show for the first time a vertebrate NatB protein N(alpha)-acetyltransferase complex essential for normal cell proliferation.


Assuntos
Acetiltransferases/metabolismo , Ciclo Celular/fisiologia , Acetilação , Acetiltransferases/genética , Western Blotting , Ciclo Celular/genética , Linhagem Celular , Citometria de Fluxo , Imunofluorescência , Humanos , Imunoprecipitação , Mutação , Ligação Proteica , Processamento de Proteína Pós-Traducional
15.
Tidsskr Nor Laegeforen ; 129(4): 300-2, 2009 Feb 12.
Artigo em Norueguês | MEDLINE | ID: mdl-19219096

RESUMO

BACKGROUND: A recent study found considerable regional differences in treatment of primary hyperparathyroidism in Norway. There is no consensus on specific indications for operation in these patients. We surveyed opinions among Norwegian endocrine surgeons and endocrinologists on the indications for surgical treatment of primary hyperparathyroidism. MATERIAL AND METHODS: A questionnaire on preoperative evaluation, indications for surgery and treatment of patients with primary hyperparathyroidism was sent to the chief consultants of surgical departments that operated on parathyroid glands in 2005. The questionnaire was also sent to endocrinologists at the same hospitals. RESULTS: In 2006, 415 parathyroid gland operations were performed in 17 Norwegian hospitals, with a median of 18 operations per hospital. A total of 46 surgeons operated on the parathyroid glands, with a median of two surgeons per hospital. Hospitals differed with respect to preoperative evaluations and indications for operative treatment; but these differences did not coincide with regional differences in the frequency of parathyroid surgery. There was a good correlation between endocrine surgeons and endocrinologists on the indications for surgery in primary hyperparathyroidism, but neither group adhered unconditionally to the international guidelines for surgical treatment of patients with primary hyperparathyroidism. Patients in the hospitals that operated most frequently were initially diagnosed in a surgical department. INTERPRETATION: Our survey did not reveal differences that could explain the large regional variations in the frequency of parathyroid surgery.


Assuntos
Hiperparatireoidismo Primário/cirurgia , Fidelidade a Diretrizes , Humanos , Hiperparatireoidismo Primário/diagnóstico , Paratireoidectomia/estatística & dados numéricos , Padrões de Prática Médica , Inquéritos e Questionários
16.
Eur Thyroid J ; 8(1): 31-40, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30800639

RESUMO

BACKGROUND: Medullary thyroid carcinoma (MTC) is rare. Nationwide population-based studies are important to evaluate its clinical course. OBJECTIVES: To describe all patients with MTC in Norway during 1994-2016 and compare time-related trends in diagnostics and surgical treatment, including prognostic factors for biochemical cure and disease-specific survival (DSS). METHODS: This retrospective population-based cohort study includes data for 228 out of 237 patients (96%) with MTC; 201 patients were surgically treated. Patients were identified in the 4 regional centers treating MTC and by the Cancer Registry of Norway. Data were collected from patients' files. Trends were compared over 2 study periods. RESULTS: MTC accounted for 4.2% of thyroid carcinomas. During the study periods, the incidence increased from 0.18 to 0.25: 100,000 per year, preoperative diagnostics improved with increased use of calcitonin, ultrasound, and fine-needle cytology (p = 0.010, p < 0,001, and p = 0.001), patients were diagnosed at an earlier tumor stage (p = 0.004), and more patients were cured (p = 0.002). Via multivariate analysis of patients with metastatic lymph nodes, independent prognostic factors for cure were: a low ratio of metastatic and total number of dissected lymph nodes (p = 0.021) and no extrathyroidal extension (p = 0.030). Independent prognostic factors for DSS were: no distant metastasis, a younger age, and a low ratio of metastatic and dissected lymph nodes (p = 0.005, p = 0.020, p = 0.022). CONCLUSIONS: Preoperative diagnostics have improved over time with increased therapeutic control. A low ratio of metastatic and dissected lymph nodes predicts better outcomes in patients with metastatic lymph nodes.

17.
J Surg Oncol ; 98(7): 551-8, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18937259

RESUMO

BACKGROUND AND OBJECTIVES: Androgen receptor (AR) is relevant for prognostication in breast cancer. Different determination methods and cut-off levels hamper interpretation and comparisons of studies. Long-term prognostic evaluation of different AR assays in patients comprising operable breast cancers is scarce. METHODS: AR was evaluated in 120 primary tumors using the dextran-coated charcoal method (charc-AR), and quantitative immunohistochemistry (IHC) on whole sections (WS) and tissue microarrays (TMA). Nuclear and cytoplasmic-AR localization was determined, and the prognostic importance of AR assays was assessed. Comparisons and correlations with the mitotic activity index (MAI), estrogen receptor (ERalpha), progesterone receptor (PR), HER-2, and histological grade (WHO I-III) were made. RESULTS: Nuclear-AR in WS, but not charc-AR, strongly correlated with MAI (P = 0.001). However, prognostic information appeared in univariate survival analyses only. Nuclear-AR in TMA was not prognostic. Charc-AR was independent prognostic in node positives both for relapse free survival (RFS) and breast cancer specific survival (BCSS). Both charc-AR and IHC cytoplasmic-AR provided independent prognostic survival information for BCSS in women <55 years. CONCLUSION: Methods that can detect AR localized in the cytoplasm yield important prognostic information, and further studies in patients with operable breast cancer are warranted.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Receptores Androgênicos/metabolismo , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Núcleo Celular/metabolismo , Carvão Vegetal , Quimioterapia Adjuvante , Citoplasma/metabolismo , Dextranos , Feminino , Humanos , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Linfonodos/metabolismo , Pessoa de Meia-Idade , Índice Mitótico , Prognóstico , Radioterapia Adjuvante , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Análise de Sobrevida , Análise Serial de Tecidos
18.
Anticancer Res ; 28(2B): 1151-60, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18505051

RESUMO

BACKGROUND: Apolipoprotein D (ApoD) is a promising prognostic and predictive factor in breast cancer, but the analysis methods and results vary. PATIENTS AND METHODS: Determination of ApoD content by immunoelectrophoresis in tumour cytosol (EPC), immunohistochemistry (IHC) in whole sections (WS) and tissue micro arrays (TMA) were compared in 283 breast carcinomas. RESULTS: With EPC, 45% and with IHC, 71% of the tumours were ApoD-positive. Correlation between the degrees of ApoD positivity by ECP and IHC was poor (R2=0.04), caused by higher sensitivity of the IHC (resulting in many ECP negative carcinomas being IHC positive) and ApoD positivity of normal tissues and cysts (resulting in ApoD positivity by ECP in up to 33% of the IHC negative cases). Discrepancies between WS and TMA were considerable due to tumour heterogeneity. CONCLUSION: In breast cancer, IHC ApoD determination is superior to EPC analysis, but intratumor heterogeneity must be carefully considered when using TMA technology.


Assuntos
Apolipoproteínas D/análise , Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Glicoproteínas/análise , Proteínas de Membrana Transportadoras/análise , Idoso , Apolipoproteínas D/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Citosol/química , Citosol/metabolismo , Feminino , Glicoproteínas/metabolismo , Humanos , Imunoeletroforese/métodos , Imuno-Histoquímica/métodos , Proteínas de Membrana Transportadoras/metabolismo , Análise em Microsséries/métodos , Pessoa de Meia-Idade , Coloração e Rotulagem/métodos
19.
Gene ; 644: 27-37, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29247799

RESUMO

N-terminal acetylation is a highly abundant and important protein modification in eukaryotes catalyzed by N-terminal acetyltransferases (NATs). In humans, six different NATs have been identified (NatA-NatF), each composed of individual subunits and acetylating a distinct set of substrates. Along with most NATs, NatC acts co-translationally at the ribosome. The NatC complex consists of the catalytic subunit Naa30 and the auxiliary subunits Naa35 and Naa38, and can potentially Nt-acetylate cytoplasmic proteins when the initiator methionine is followed by a bulky hydrophobic/amphipathic residue at position 2. Here, we have identified a splice variant of human NAA30, which encodes a truncated protein named Naa30288. The splice variant was abundantly present in thyroid cancer tissues and in several different human cancer cell lines. Surprisingly, Naa30288 localized predominantly to the nucleus, as opposed to annotated Naa30 which has a cytoplasmic localization. Full-length Naa30 acetylated a classical NatC substrate peptide in vitro, whereas no significant NAT activity was detected for Naa30288. Due to the nuclear localization, we also examined acetyltransferase activity towards lysine residues. Neither full-length Naa30 nor Naa30288 displayed any lysine acetyltransferase activity. Overexpression of full-length Naa30 increased cell viability via inhibition of apoptosis. In contrast, Naa30288 did not exert an anti-apoptotic effect. In sum, we identified a novel and widely expressed Naa30 isoform with a potential non-catalytic role in the nucleus.


Assuntos
Núcleo Celular/genética , Acetiltransferase N-Terminal C/genética , Acetiltransferases N-Terminal/genética , Isoformas de Proteínas/genética , Splicing de RNA/genética , Acetilação , Sequência de Aminoácidos , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Células HEK293 , Células HeLa , Humanos , Lisina/genética , Células MCF-7 , Processamento de Proteína Pós-Traducional/genética , Ribossomos/genética
20.
J Clin Endocrinol Metab ; 92(5): 1687-92, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17284629

RESUMO

CONTEXT: The clinical presentation of primary hyperparathyroidism (pHPT) has changed during the last half century, and the diagnosis is now more often made by chance in patients with no specific symptoms. OBJECTIVE: The present study is a randomized, controlled trial that investigates the effects of parathyroidectomy or medical observation in mild asymptomatic pHPT on morbidity and quality of life (QoL). DESIGN/SETTING/PATIENTS: A total of 191 patients (26 men) with asymptomatic pHPT [mean age 64.2 +/- 7.4 (sd) yr] were recruited in the study and randomized to medical observation (serum calcium level 2.69 +/- 0.08 mmol/liter) or surgery (2.70 +/- 0.08 mmol/liter). We here report baseline and 1 (n = 119) and 2 yr data (n = 99) on those who had completed the follow-up visits by the end of the inclusion period. RESULTS: At baseline, the patients had significantly lower QoL (SF-36) and more psychological symptoms, compared with age- and sex-matched healthy subjects. The two groups were similar at baseline, and no clinically significant changes in these parameters were seen during the observation time. Calcium and PTH normalized after surgery. The areal bone mineral density increased in the group randomized to operation, whereas the bone mineral density remained stable in the medical observation group. No change in kidney function (creatinine) or blood pressure was observed longitudinally or between the groups. CONCLUSIONS: Asymptomatic patients with mild pHPT have decreased QoL and more psychological symptoms than normal controls. No benefit of operative treatment, compared with medical observation, was found on these measures so far.


Assuntos
Hiperparatireoidismo Primário/cirurgia , Hiperparatireoidismo Primário/terapia , Paratireoidectomia , Idoso , Pressão Sanguínea/fisiologia , Densidade Óssea , Feminino , Seguimentos , Humanos , Hiperparatireoidismo Primário/psicologia , Testes de Função Renal , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários
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