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1.
Hum Reprod ; 20(9): 2653-60, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15905289

RESUMO

BACKGROUND: This study was designed to assess the long-term efficacy (5 years) of the levonorgestrel-releasing intrauterine system (LNG-IUS) in protecting the endometrium from hyperplasia during estrogen replacement therapy in perimenopausal women. METHODS: Prospective, open, outpatient clinical trial in London and Oxford. Eighty-two women received oral conjugated equine estrogen 1.25 mg daily and LNG-IUS releasing 20 mug levonorgestrel per 24 h. Endometrial biopsy and histological assessment were performed annually. Endometrial thickness was measured by vaginal ultrasonography. RESULTS: Non-proliferative endometrium was present at the end of cycles 12, 24, 36, 48 and 60 in 98.6, 98.6, 95.5, 96.8 and 95.2% of the participants respectively. No endometrial hyperplasias were confirmed throughout a period of 60 cycles. The proportion of amenorrhoeic women increased from 54.4% at 12 cycles to 92.7% at the end of the study. The continuation rate per 100 women at 60 cycles was 79.84 (95% CI 71.0-88.6). CONCLUSIONS: The LNG-IUS with estrogen supplementation in perimenopausal women suppresses endometrial proliferation resulting in amenorrhoea and relieves vasomotor symptoms. The treatment regimen is well tolerated and provides an alternative strategy for perimenopausal women with the likelihood of increasing compliance.


Assuntos
Anticoncepcionais Femininos/administração & dosagem , Hiperplasia Endometrial/prevenção & controle , Terapia de Reposição de Estrogênios/métodos , Estrogênios/administração & dosagem , Levanogestrel/administração & dosagem , Administração Oral , Adulto , Animais , Anticoncepcionais Femininos/efeitos adversos , Hiperplasia Endometrial/tratamento farmacológico , Terapia de Reposição de Estrogênios/efeitos adversos , Estrogênios/efeitos adversos , Feminino , Cavalos , Humanos , Levanogestrel/efeitos adversos , Pessoa de Meia-Idade , Perimenopausa , Estudos Prospectivos , Resultado do Tratamento , Hemorragia Uterina/tratamento farmacológico , Hemorragia Uterina/prevenção & controle
2.
Clin Endocrinol (Oxf) ; 57(4): 487-500, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12354131

RESUMO

OBJECTIVE: Suprasellar germ cell tumours are rare, and there are few series of patients outlining the problems in diagnosis and management, and providing clear guidelines for optimal therapy. We have therefore reviewed our own series of 11 such patients who were managed in a joint endocrinology/clinical oncology setting. PATIENTS AND DESIGN: A retrospective case review assessment of all patients seen within a given time. Clinical, biochemical and radiological findings were reviewed, the types of therapy administered noted, and the responses to treatment analysed. RESULTS: In the years 1977-2001, 11 patients with suprasellar (SS) germ cell tumours (GCT) were seen (germinomatous : nongerminomatous = 8 : 3). SSGCT had an approximately equal sex incidence (M : F, 6 : 5), in contrast to pineal tumours, the commonest site of origin of intracranial GCT and which occur predominantly in men. The median age at presentation was 20 years (range 6-49 years) with a median duration of symptoms before diagnosis of 17 months (range 1-35 months). Polyuria was the commonest presenting symptom (10 patients). Diabetes insipidus occurred in all patients, as did partial or complete anterior pituitary failure. Visual failure was present in 55% of cases. Anorexia, weight loss and disturbed thirst sensation were also common. Positron emission tomography scanning was occasionally useful in the evaluation of suprasellar tumours/pituitary stalk lesions deemed too risky to biopsy. A "central nervous system-friendly" chemoradiotherapy regimen comprising vincristine, etoposide and carboplatin and differential daily dose irradiation, usually administered using a partial transmission block technique, produced a 5-year survival of 100% with low morbidity. Treatment did not correct previously abnormal endocrine function although it did improve vision in three of six patients. CONCLUSIONS: We therefore emphasize the use of techniques other than biopsy in the diagnosis of these patients, note the problems in the management of their fluid control, and highlight the favourable response to a combined chemotherapy-radiotherapy protocol.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/terapia , Sela Túrcica , Adolescente , Adulto , Algoritmos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/complicações , Criança , Terapia Combinada , Diabetes Insípido/etiologia , Intervalo Livre de Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/complicações , Estudos Retrospectivos , Resultado do Tratamento , Transtornos da Visão/etiologia
3.
Br J Cancer ; 87(5): 537-44, 2002 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-12189553

RESUMO

To date, numerous genes have been identified which are involved in both tumour neovascularisation (angiogenesis) and tumour cell invasion, and most of them are also expressed to some extent under normal physiological conditions. However, little is known about how these genes co-express in these settings. This study was undertaken to quantitate mRNA levels in normal and malignant cervical tissues of nine selected genes (VEGF(121), VEGF(165), VEGF(189), VEGF-C, eIF-4E, b-FGF, TSP-2, MMP-2 and MMP-9) implicated in the above processes using real-time quantitative RT-PCR. In addition, the Spearman's rank correlation was used to determine their co-expression patterns. The transcript levels for the different VEGF-A splice variants (VEGF(121), VEGF(165), VEGF(189)) were at least 10-fold higher in the cancer cases, with the highest levels in the primary tumours demonstrating lympho-vascular space involvement. The lymphangiogenic factor VEGF-C and MMP-9 were upregulated 130- and 80-fold respectively in cervical cancers. The highest levels of VEGF-C mRNA were found in the lymph-node positive group. The transcript levels for b-FGF were similar in normal cervical tissue and early-stage cervical cancer, however, higher levels were found in the cervical cancers with advanced stage disease. Comparing gene transcript levels between recurrent and non-recurrent cervical cancer patients revealed significant differences (P=0.038) in transcript levels for the angiogenesis inhibitor TSP-2, with the highest levels in non-recurrent cases. Co-expression pattern analysis in normal cervical tissue revealed highly significant co-expressions (P<0.0001) between TSP-2 and most other genes analysed (VEGF(121), VEGF(165), VEGF-C, b-FGF and MMP-2). In cervical cancer, TSP-2 appears only to be highly co-expressed with MMP-2 (P<0.0001). In contrast to normal cervical tissue, we found a highly significant co-expression (P<0.0001) between MMP-9 and VEGF(189) in cervical cancer. The combined application of real-time quantitative RT-PCR and Spearman's rank correlation identifies gene transcripts which are simultaneously co-expressed. Our results revealed a significant co-expression between the angiogenesis inhibitor TSP-2 and most other genes analysed in normal cervical tissue. In cervical cancer, we found a strong upregulation of VEGF-C and MMP-9 mRNA, with a highly significant co-expression between MMP-9 and VEGF(189).


Assuntos
Regulação Neoplásica da Expressão Gênica , Modelos Genéticos , Invasividade Neoplásica/genética , Proteínas de Neoplasias/genética , Neovascularização Patológica/genética , Neovascularização Fisiológica/genética , Neoplasias do Colo do Útero/genética , Colo do Útero/metabolismo , Fatores de Crescimento Endotelial/biossíntese , Fatores de Crescimento Endotelial/genética , Fator de Iniciação 4E em Eucariotos , Feminino , Fatores de Crescimento de Fibroblastos/biossíntese , Fatores de Crescimento de Fibroblastos/genética , Humanos , Linfocinas/biossíntese , Linfocinas/genética , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/genética , Proteínas de Neoplasias/biossíntese , Recidiva Local de Neoplasia , Fatores de Iniciação de Peptídeos/biossíntese , Fatores de Iniciação de Peptídeos/genética , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , RNA Mensageiro/biossíntese , RNA Ribossômico 18S/biossíntese , RNA Ribossômico 18S/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Neoplasias do Colo do Útero/metabolismo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
4.
Clin Endocrinol (Oxf) ; 54(4): 499-508, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11318786

RESUMO

OBJECTIVE: Patients with acromegaly are at increased risk of developing colorectal carcinoma and premalignant tubulovillous adenoma. The pathogenesis of these neoplasms could involve a stimulatory effect of serum growth factors on colonic epithelial cell proliferation. The aim of this study was to evaluate changes in (1) serum IGF-I, IGF-II, IGFBP-3 and IGFBP-2 and (2) changes in local expression of IGFBPs and p53 in colonic epithelium in patients with colonic neoplasia with and without acromegaly. DESIGN: A cross-sectional retrospective study was performed. Fasting serum samples were obtained at the time of colonoscopy for patients with acromegaly and at the time of surgery for patients with colonic neoplasia without acromegaly. MEASUREMENTS: Serum IGF-I, IGF-II, IGFBP-2 and IGFBP-3 were measured using specific immunoassays. Tissue expression of IGFBP-2, IGFBP-3 and p53 status were determined by immunohistochemistry. PATIENTS: Group 1: 26 age- and sex-matched control subjects (range 40-69 years); group 2: 18 patients with acromegaly without colonic neoplasia (range 39-68 years); group 3: 18 patients with acromegaly and colonic neoplasia (range 41-74 years, 11 = adenoma, seven = carcinoma); group 4: 19 patients with colonic neoplasia without endocrine disease (range 43-91 years, four = adenoma, 15 = carcinoma). Immunohistochemical staining of colonic biopsies was performed for IGFBP-2, IGFBP-3 and p53 in groups 3 and 4. RESULTS: Mean serum IGF-I and IGFBP-3 levels were significantly elevated in group 2 (371 +/- 131 microg/l and 6.5 +/- 1.8 mg/l, respectively) and group 3 (379 +/- 174 microg/l and 5.8 +/- 1.6 mg/l, respectively), and significantly reduced in group 4 (103 +/- 36 microg/l and 2.4 +/- 1 mg/l) compared to controls (165 +/- 40 microg/l and 4.7 +/- 1 mg/l; P < 0.0001, P < 0.001, respectively). However, median serum IGFBP-2 levels were significantly elevated in group 3 (P < 0.01) and group 4 (P < 0.0001). Immunostaining for IGFBP-2 showed strong areas of immunoreactivity in the cytoplasm of malignant colonic epithelium compared to benign epithelium. IGFBP-3 immunostaining showed strong areas of immunoreactivity in the cytoplasm and in the nucleus of malignant and benign colonic epithelium compared to the normal epithelium. Nuclear staining for p53 was observed in three patients from group 3 (two carcinoma, one adenoma) and four patients from group 4 (all carcinoma). CONCLUSION: Our results describe changes in IGFBP-2 expression in colonic neoplasia in patients with and without acromegaly, which suggest that this binding protein may regulate local bioavailability of IGF, which in turn could modulate colonic cell proliferation and/or differentiation.


Assuntos
Acromegalia/sangue , Adenoma/química , Carcinoma/química , Neoplasias do Colo/química , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Acromegalia/complicações , Adenoma/sangue , Adenoma/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/sangue , Carcinoma/complicações , Estudos de Casos e Controles , Colo/química , Neoplasias do Colo/sangue , Neoplasias do Colo/complicações , Estudos Transversais , Epitélio/química , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/análise , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like II/análise , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estatísticas não Paramétricas , Proteína Supressora de Tumor p53/análise
5.
J Clin Endocrinol Metab ; 86(1): 386-91, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11232029

RESUMO

A 37-yr-old woman with clinical, endocrinological, and radiological features suggestive of a nonfunctioning pituitary tumor was found to have a chondrosarcoma of the pituitary sella. The bony structures around the sella were relatively uninvolved, other than showing minor erosion of the left side of the dorsum and the posterior wall of the sphenoid sinus. After partial resection of the tumor by the transsphenoidal route the patient received postoperative radiosurgery by a linear accelerator, stereotactic multiarc radiotherapy. Subsequent follow-up revealed reduction of the residual tumor. This case demonstrates that a chondrosarcoma may apparently arise directly from the pituitary fossa and suggests the efficacy of stereotactic radiosurgery, at least in the medium term. The origin, areas of involvement, management, and long-term prognosis of these rare tumors are reviewed.


Assuntos
Adenoma/diagnóstico , Condrossarcoma/diagnóstico , Neoplasias Hipofisárias/diagnóstico , Sela Túrcica , Neoplasias Cranianas/diagnóstico , Adulto , Condrossarcoma/patologia , Condrossarcoma/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Radiocirurgia , Neoplasias Cranianas/patologia , Neoplasias Cranianas/cirurgia , Técnicas Estereotáxicas , Tomografia Computadorizada por Raios X
6.
Lancet ; 357(9249): 15-20, 2001 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-11197354

RESUMO

BACKGROUND: A proportion of patients with cancer and lymph nodes negative on histology will develop recurrence. Reverse-transcriptase PCR (RT-PCR) is a highly sensitive method for detection of lymph-node micrometastases, but accurate quantitative assessment has been difficult. METHODS: We studied primary tumours and 156 lymph nodes from 32 patients with cervical cancer (stage IA2, IB1, and IB2) and 32 lymph nodes from nine patients with benign disease. A fully quantitative, real-time RT-PCR assay was used to document absolute copy numbers of the epithelial marker cytokeratin 19. Primers and probe were designed not to amplify either of the two cytokeratin 19 pseudogenes. FINDINGS: All primary tumours and histologically involved lymph nodes (six) had more than 106 copies of cytokeratin 19 mRNA per microg total RNA. Expression of cytokeratin 19 (up to 1.1 x 10(5) copies per microg RNA) was detected in 66 (44%) of 150 histologically uninvolved lymph nodes, and in nodes from 16 of 32 patients with cervical cancer. 15 of these 16 patients with evidence of micrometastases had the highest cytokeratin 19 transcription level in a first lymph-node drainage station (three obturator, six internal, and six external iliac node). Transcription of cytokeratin 19 was found at a low level in just one of 32 lymph nodes obtained from nine patients with benign disease. Median copy number of cytokeratin 19 transcription was significantly higher (>10(3) copies) in association with adverse prognostic features. INTERPRETATION: The results suggest that about 50% of early-stage cervical cancers shed tumour cells to the pelvic lymph nodes. The amount of cytokeratin 19 expression was related to clinicopathological features. Further studies are required to document the clinical implications of molecular micrometastases.


Assuntos
Queratinas/genética , Linfonodos/metabolismo , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Sequência de Bases , Feminino , Seguimentos , Humanos , Linfonodos/patologia , Metástase Linfática , Pessoa de Meia-Idade , Dados de Sequência Molecular , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Neoplasias do Colo do Útero/genética
7.
J Clin Endocrinol Metab ; 86(2): 881-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11158061

RESUMO

Ghrelin is a recently identified endogenous ligand of the GH secretagogue (GHS) receptor. It was originally isolated from the stomach, but has also been shown to be present in the rat hypothalamus. It is a 28-amino acid peptide with an unusual octanoylated serine 3 at the N-terminal end of the molecule, which is crucial for its biological activity. Synthetic GHSs stimulate GH release via both the hypothalamus and the pituitary, and the GHS receptor (GHS-R) has been shown by us and others to be present in the pituitary. We investigated whether ghrelin messenger ribonucleic acid (mRNA) and peptide are present in the normal human hypothalamus and in normal and adenomatous human pituitary. RNA was extracted from pituitary tissue removed at autopsy and transsphenoidal surgery (n = 62), and ghrelin and GHS-R type 1a and 1b mRNA levels were investigated using real-time RT-PCR. Both ghrelin and GHS-R mRNA were detected in all samples. Corticotroph tumors showed significantly less expression of ghrelin mRNA, whereas GHS-R mRNA levels were similar to those in normal pituitary tissue. Gonadotroph tumors showed a particularly low level of expression of GHS-R mRNA. Immunohistochemistry, using a polyclonal antibody against the C-terminal end of the ghrelin molecule, revealed positive staining in the homolog of the arcuate nucleus in the human hypothalamus and in both normal and abnormal human pituitary. Pituitary tumor ghrelin peptide content was demonstrated using two separate RIA reactions for the N-terminal and C-terminal ends of the molecule. Both forms were present in normal and abnormal pituitaries, with 5 +/- 2.5% octanoylated (active) ghrelin (mean +/- SD) present as a percentage of the total. We suggest that the presence of ghrelin mRNA and peptide in the pituitary implies that the locally synthesized hormone may have an autocrine/paracrine modulatory effect on pituitary hormone release.


Assuntos
Hipotálamo/metabolismo , Tumores Neuroendócrinos/genética , Hormônios Peptídicos , Peptídeos/genética , Hipófise/metabolismo , Neoplasias Hipofisárias/genética , Receptores de Superfície Celular/genética , Receptores Acoplados a Proteínas G , Transcrição Gênica , Adulto , Idoso , Animais , Sequência de Bases , Primers do DNA , Feminino , Mucosa Gástrica/metabolismo , Grelina , Hormônio do Crescimento Humano/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Tumores Neuroendócrinos/patologia , Peptídeos/análise , Neoplasias Hipofisárias/patologia , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/genética , Ratos , Receptores de Grelina , Valores de Referência
8.
J Clin Endocrinol Metab ; 85(9): 3218-21, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10999811

RESUMO

Patients with acromegaly are at increased risk of colorectal neoplasia and, by analogy with high-risk nonacromegalic patients, may require regular colonoscopic screening. However, it is unknown whether the risk is equal in all patients or whether some should be regarded as carrying a particularly high risk. The aims of this study were: 1) to establish the natural history of colorectal neoplasia in acromegaly; 2) to establish which patients are at increased risk of developing neoplasia; and 3) to elucidate the influence of insulin-like growth factor I (IGF-I) in adenoma formation. A prospective colonoscopic evaluation of the development of new premalignant adenomas in the colon was performed in 66 patients with biochemically proven acromegaly who had previously undergone colonoscopic screening and removal of all visible polyps. Twenty-five patients (38%) had a total of 37 polyps detected at the second colonoscopy: nine (14%) had at least one adenoma, and 18 (27%) had one or more hyperplastic polyps (2 patients had both). The development of new adenomas, but not hyperplastic polyps, was associated both with elevated serum IGF-I (P < 0.005) and, to a lesser extent, with a previous adenoma at the original colonoscopy (P < 0.07). In summary, patients with acromegaly and in whom serum IGF-I remains elevated and/or who have had a previous adenoma should be regarded as having an especially high risk for the development of subsequent colorectal neoplasia. Serum IGF-I seems to be implicated in the development of colorectal neoplasia in acromegaly, although the exact mechanisms remain uncertain.


Assuntos
Acromegalia/complicações , Neoplasias Colorretais/etiologia , Fator de Crescimento Insulin-Like I/metabolismo , Acromegalia/patologia , Adenoma/patologia , Idoso , Colonoscopia , Neoplasias Colorretais/patologia , Feminino , Hormônio do Crescimento Humano/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos/patologia , Estudos Prospectivos
9.
J Neurosci ; 20(14): 5200-7, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10884303

RESUMO

Metallothioneins (MTs) are cysteine-rich metal-binding proteins that are potentially involved in zinc homeostasis and free radical scavenging. The expression pattern of MT-1 and the binding activity of various MT-1 promoter elements were investigated after mild focal cerebral ischemia in the rat. Transient focal ischemia was induced by occluding both common carotid arteries and the right middle cerebral artery for 30 min. By the use of real-time quantitative PCR, a 10-fold increase in MT-1 and -2 mRNA levels was found in the cortex 24 hr after reperfusion. In situ hybridization and immunocytochemistry showed a rapid increase in MT-1 and -2 mRNA and MT protein in endothelial cells of microvessels at 6 hr after reperfusion, followed by an increased expression in astrocytes of the infarcted cortex at 24 hr after reperfusion. The early increase in MT expression preceded an increase in cerebral edema measured with T2-weighted magnetic resonance imaging. Gel shift assays were performed on nuclear extracts prepared from cortices before and at 6 and 24 hr after reperfusion. Increased binding activity was found at an antioxidant/electrophilic response element (ARE) sequence in the MT-1 promoter at 6 hr with a lower and variable binding activity at 24 hr after reperfusion. Constitutive binding activity was found for Sp1 and a metal response element in the MT-1 promoter that did not increase after ischemia and reperfusion. This study suggests a role of ARE-binding proteins in inducing cerebral MT-1 expression and implicates MT-1 as one of the early detoxifying genes in an endogenous defense response to cerebral ischemia and reperfusion.


Assuntos
Antioxidantes/metabolismo , Isquemia Encefálica/metabolismo , Metalotioneína/biossíntese , Regiões Promotoras Genéticas/genética , Elementos de Resposta/fisiologia , Animais , Antioxidantes/farmacologia , Edema Encefálico/metabolismo , Edema Encefálico/patologia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/cirurgia , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Proteínas de Ligação a DNA/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Imageamento por Ressonância Magnética , Metalotioneína/genética , Neuroglia/metabolismo , Neuroglia/patologia , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Long-Evans , Reperfusão , Elementos de Resposta/efeitos dos fármacos , Fator de Transcrição Sp1/metabolismo , Fatores de Transcrição/metabolismo
10.
Eur J Endocrinol ; 143(1): R1-6, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10870044

RESUMO

OBJECTIVES: Cyclins play an important role in the regulation of cell progression through the cell cycle. Over-expression of the cyclins has been shown in many different tumour types. Pituitary adenomas are a common form of endocrine neoplasia in the human, but have been little studied in terms of the expression of the principal cyclins regulating checkpoint exit, cyclin D1 and cyclin E. METHODS: We therefore investigated the expression of cyclin D1 and cyclin E in a range of benign and metastatic pituitary tumours. We studied a total of 95 pituitaries, including normal pituitary (n=20), Cushing's disease (n=19), somatotroph tumours (n=19), non-functioning adenomas (n=18), prolactinomas (n=7), aggressive tumours (n=9) and pituitary carcinoma (n=3). All tumours and normal tissue were immunostained for cyclin D1 and cyclin E using a standard technique, and were then subjected to blinded analysis by a single observer and the extent of staining quantified on the basis of 500 cell counts per tissue. The distribution of positive staining between different tissues was analysed by non-parametric test procedures. RESULTS: There was no cytoplasmic staining for cyclin D1 in any tissue. Nuclear staining was generally sparse, but was statistically more frequent in non-functioning and aggressive tumours compared with other tumour types or normal pituitary. Cyclin E was also sparsely expressed, but was specifically increased in corticotroph tumours from patients with Cushing's disease. CONCLUSIONS: We report cyclin D1 over-expression in aggressive and non-functioning pituitary tumours, and that cyclin E expression is more frequently seen in Cushing's disease. The high level of cyclin E expression in Cushing's disease may relate to the low level of p27 protein expression previously reported in corticotroph tumours.


Assuntos
Adenoma/química , Ciclina E/análise , Ciclinas/análise , Neoplasias Hipofisárias/química , Núcleo Celular/química , Síndrome de Cushing/metabolismo , Ciclina D , Feminino , Hormônio do Crescimento Humano/metabolismo , Humanos , Imuno-Histoquímica , Hipófise/química , Gravidez , Prolactinoma/química
12.
Clin Endocrinol (Oxf) ; 53(6): 749-53, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11155098

RESUMO

A 43-year-old female with a 24-years history of hypertension presented for further investigation and management of primary hyperaldosternoism. Postural studies were not conclusive and magnetic resonance (MR) imaging demonstrated a 27 x 18 mm lesion of the right adrenal gland which showed no signal loss during in and out of phase imaging. Although these appearances were considered to be atypical of those seen on MR in patients with aldosterone producing adrenal adenomas the patient underwent an adrenalectomy with removal of a 3 x 3 x 2 cm right adrenal mass. Post-operatively she became hypotensive and a 0900 hours serum cortisol was undetectable (< 50 nmol/l), consistent with adrenal insufficiency. Following the administration of hydrocortisone there was normalization of the blood pressure and subsequent adrenal stimulation tests confirmed the presence of functioning adrenal tissue albeit with an inadequate response. Cortisol measurement from preoperative samples revealed loss of normal diurnal rhythm whereas DHEAS levels both pre and postoperatively were undetectable, consistent with ACTH supression resulting from autonomous cortisol secretion in addition to aldosterone. Concurrent secretion of cortisol should always be considered in Conn's adenomas particularly when atypical radiological features are present.


Assuntos
Adenoma/diagnóstico , Neoplasias das Glândulas Suprarrenais/diagnóstico , Imageamento por Ressonância Magnética , Adenoma/metabolismo , Adenoma/cirurgia , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia , Adulto , Aldosterona/metabolismo , Cosintropina , Feminino , Humanos , Hidrocortisona/metabolismo , Proteínas de Neoplasias/metabolismo
13.
J Clin Endocrinol Metab ; 84(10): 3823-30, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10523037

RESUMO

The cell cycle is regulated by a number of inhibitors, including p27Kip1 (p27), which belongs to the kip1 family. By binding to the cyclin/cyclin-dependent kinase complexes, it regulates progression of G1 to S phase in the cell cycle. It has been reported that p27 knockout mice develop multiorgan hyperplasia and intermediate lobe pituitary tumors secreting ACTH. Previously, we and others have been unable to show any consistent change in messenger RNA expression or genomic mutations for p27 in human corticotroph adenomas. However, dysregulation at the protein level has been reported in nonendocrine tumors, and we, therefore, investigated the expression of p27 in a range of benign and metastatic pituitary tumors. We studied a total of 107 pituitaries, including normal pituitary (n = 20), Cushing's disease (n = 21), acromegaly (n = 19), nonfunctioning adenomas (n = 18), prolactinomas (n = 7), TSH-omas (n = 2), FSH-omas (n = 6), aggressive tumors showing invasiveness and recurrence (n = 9), and metastatic pituitary carcinomas (n = 5). Using standard immunohistochemical techniques with a highly specific monoclonal antibody, p27 expression was determined quantitatively as the percentage of cells showing strongly positive, weak, or negative staining. In each sample, approximately 500 cells were analyzed. We also analyzed normal pituitaries using double-labeling for p27 and each of the pituitary hormones to characterize the expression of p27 in each cell type. p27 was expressed in normal pituitary cells; in tumors expressing GH, prolactin, TSH, and FSH; and in aggressive tumors, but markedly reduced expression of p27 was seen in corticotroph tumors and pituitary carcinomas. In the normal pituitary, somatotroph, lactotroph, and thyrotroph cells showed strong p27 staining, whereas normal corticotroph cells showed a much lower level of p27 staining (P < 0.001). Somatotroph, lactotroph, gonadotroph, and thyrotroph adenomas showed a lower level of p27 expression compared with normal somatotrophs (P = 0.02), lactotrophs (P = 0.03), gonadotrophs (P = 0.01), and thyrotrophs, respectively, whereas the lower level of p27 expression present in normal corticotrophs virtually disappeared in corticotroph adenomas (P = 0.001). We conclude that pituitary adenomas show a lower level of p27 protein expression than the normal cells from which they are derived, with malignant transformation leading to complete loss of p27 immunoreactivity. Corticotrophs are quite different to other pituitary cell types in terms of p27 immunoreactivity because both normal and tumorous corticotrophs have low p27 staining, and we speculate that this may relate to their inherent control mechanisms.


Assuntos
Adenoma/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Proteínas de Ciclo Celular , Proteínas Associadas aos Microtúbulos/metabolismo , Adeno-Hipófise/metabolismo , Neoplasias Hipofisárias/metabolismo , Proteínas Supressoras de Tumor , Adenoma/patologia , Ciclo Celular/fisiologia , Inibidor de Quinase Dependente de Ciclina p27 , Humanos , Imuno-Histoquímica , Proteínas Associadas aos Microtúbulos/genética , Adeno-Hipófise/citologia , Neoplasias Hipofisárias/patologia , RNA Mensageiro , Valores de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Lancet ; 353(9160): 1207-10, 1999 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-10217079

RESUMO

BACKGROUND: The value of screening for ovarian cancer is uncertain. We did a pilot randomised trial to assess multimodal screening with sequential CA 125 antigen and ultrasonography. METHODS: Postmenopausal women aged 45 years or older were randomised to a control group (n=10,977) or screened group (n=10,958). Women randomised to screening were offered three annual screens that involved measurement of serum CA 125, pelvic ultrasonography if CA 125 was 30 U/mL or more, and referral for gynaecological opinion if ovarian volume was 8.8 mL or more on ultrasonography. All women were followed up to see whether they developed invasive epithelial cancers of the ovary or fallopian tube (index cancers). FINDINGS: Of 468 women in the screened group with a raised CA 125, 29 were referred for a gynaecological opinion; screening detected an index cancer in six and 23 had false-positive screening results. The positive predictive value was 20.7%. During 7-year follow-up, ten further women with index cancers were identified in the screened group and 20 in the control group. Median survival of women with index cancers in the screened group was 72.9 months and in the control group was 41.8 months (p=0.0112). The number of deaths from an index cancer did not differ significantly between the control and screened groups (18 of 10,977 vs nine of 10,958, relative risk 2.0 [95% CI 0.78-5.13]). INTERPRETATION: These results show that a multimodal approach to ovarian cancer screening in a randomised trial is feasible and justify a larger randomised trial to see whether screening affects mortality.


Assuntos
Antígeno Ca-125/sangue , Neoplasias Ovarianas/diagnóstico , Reações Falso-Positivas , Feminino , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/mortalidade , Projetos Piloto , Pós-Menopausa , Taxa de Sobrevida , Ultrassonografia , Reino Unido
15.
Endocrinology ; 140(3): 1118-24, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10067834

RESUMO

Natriuretic peptides suppress adrenergic neurotransmission by a mechanism apparently involving the natriuretic peptide receptor-C (NPR-C) rather than particulate guanylyl cyclase receptors. The bulk of evidence implicating the NPR-C in neuromodulatory effects relies on the pharmacological specificity of peptides believed to be specific for the NPR-C. This study tests for NPR-C effects on neurotransmitter release by examining fragments of the receptor for biological activity in pheochromocytoma (PC12) cells permeabilized with digitonin. A pentadecapeptide segment of the cytoplasmic portion of the NPR-C mimicked the effect of natriuretic peptides to suppress dopamine efflux evoked by calcium approximately 40%. Furthermore, an antibody generated against the pentadecapeptide fragment abolished the neuromodulatory effect of C-type natriuretic peptide in permeabilized cells. In contrast, the carboxy terminal nonadecapeptide portion of the NPR-C failed to attenuate dopamine efflux. These data are consistent with the proposed role of the NPR-C in transducing the biological activity of natriuretic peptides in adrenergic tissue. The most novel aspect of these observations involves the potency of the small cytosolic region of the NPR-C with the region closest to the membrane accounting for neuromodulatory effects.


Assuntos
Citosol/química , Dopamina/metabolismo , Guanilato Ciclase/química , Neurotransmissores/fisiologia , Fragmentos de Peptídeos/fisiologia , Receptores do Fator Natriurético Atrial/química , Adenilil Ciclases/metabolismo , Sequência de Aminoácidos , Análise de Variância , Animais , Formação de Anticorpos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Digitonina/farmacologia , Dados de Sequência Molecular , Neurotransmissores/metabolismo , Células PC12 , Fragmentos de Peptídeos/imunologia , Ratos
17.
J Clin Endocrinol Metab ; 83(10): 3542-4, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9768661

RESUMO

We report the emergency and prolonged use of etomidate to control circulating cortisol levels in a patient with Cushing's syndrome secondary to ectopic ACTH production from a pancreatic islet cell tumor. Duodenal perforation and peritonitis complicated an episode of salmonella septicemia, precluding the use of conventional oral medical adrenolytic therapy. Endogenous cortisol secretion was abolished by parenteral etomidate, allowing serum cortisol levels to be controlled with an iv infusion of hydrocortisone over an 8-week period in intensive care before definitive pancreatic surgery.


Assuntos
Síndrome de Cushing/sangue , Serviços Médicos de Emergência , Etomidato/administração & dosagem , Hidrocortisona/sangue , Peritonite/complicações , Adenoma de Células das Ilhotas Pancreáticas/metabolismo , Adenoma de Células das Ilhotas Pancreáticas/cirurgia , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Síndrome de Cushing/complicações , Síndrome de Cushing/etiologia , Etomidato/uso terapêutico , Humanos , Hidrocortisona/antagonistas & inibidores , Hidrocortisona/uso terapêutico , Injeções Intravenosas , Masculino , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/cirurgia , Cuidados Pré-Operatórios
18.
Clin Endocrinol (Oxf) ; 48(3): 367-72, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9578829

RESUMO

A boy aged 6 years presented with genital precocity, enlarged testes and advanced linear growth. An ovoid mass 3-4 cm in diameter was identified by MRI scan in the right adrenal gland. Serum concentrations of LH, testosterone, alpha-subnuit, dehydroepiandrosterone sulphate, androstenedione and oestradiol were persistently elevated. LH was unresponsive to bolus i.v. injection of GnRH or to GnRH analogue therapy. Serum FSH was normal. After removal of the adrenal tumour, serum LH, alpha-subunit, testosterone and adrenal androgen levels fell to normal. In incubation medium of cultured disaggregated tumour cells, LH concentrations were greater than twice the mean serum concentration and 4-5-fold higher than in the medium of cultured non-neoplastic adrenal cells. Specific immunostaining of the tumour was positive for LH and alpha-subunit in many areas and these were not found in the adjacent non-neoplastic adrenal. Testicular biopsy showed almost complete spermatogenesis although germinal cell types were numerically lower than in normal men. These findings are consistent with an adrenocortical adenoma secreting LH being the cause of the patient's precocious puberty.


Assuntos
Adenoma/complicações , Adenoma/metabolismo , Neoplasias do Córtex Suprarrenal/complicações , Neoplasias do Córtex Suprarrenal/metabolismo , Hormônio Luteinizante/metabolismo , Puberdade Precoce/etiologia , Adenoma/sangue , Adenoma/patologia , Neoplasias do Córtex Suprarrenal/sangue , Neoplasias do Córtex Suprarrenal/patologia , Androstenodiona/sangue , Criança , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Subunidade alfa de Hormônios Glicoproteicos/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Puberdade Precoce/sangue , Testosterona/sangue
19.
Oncogene ; 16(1): 69-76, 1998 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-9467944

RESUMO

The molecular mechanisms leading to Cushing's disease are unclear. Inhibitors of cyclin-cyclin dependent kinase (CDK) complexes are regulators of the cell cycle and may function as tumour suppressor genes, many of which have been involved in the pathogenesis of several human malignancies. A member of this family, the p27/kip1 gene, maps to chromosome 12p13 and encodes an inhibitor of several cyclin-CDK complexes; these control the progression of the cell cycle from G1 to S-phase. Complete lack of p27/kip1 function, as occurs in the p27/kip1 'knockout' mouse, produces a complex phenotype associated with the development of pituitary tumours, specifically those of the intermediate lobe corticotrophs. We therefore investigated whether structural and functional abnormalities of the p27/kip1 gene and loss at the chromosome 12p13 region were present in human corticotrophin (ACTH)-secreting pituitary tumours. We studied 21 pituitary tumours, of which 20 were ACTH-secreting (two of these had biochemical and histological features of 'intermediate-lobe' tumours and one was malignant) while the remaining tumour was a prolactinoma; three ectopic secretors of ACTH (two bronchial and one thymic carcinoid); and a non-secretory thymic carcinoid. The whole coding region of the p27/ kip1 gene was screened for mutations by PCR-SSCP analysis and/or direct sequencing, while tumour mRNA expression was analysed by means of a semi-quantitative duplex PCR. Three polymorphic microsatellite markers of the 12p13 region were used to assess loss of heterozygosity (LOH) in 12 samples. Finally, tumour p27/kip1 protein expression was assessed by immunohistochemistry using a monoclonal antibody in 12 samples suitable for analysis. No sequence abnormalities were found in any of the samples other than a previously-described polymorphism. No LOH was observed in the tumours analysed. p27/kip1 mRNA expression was similar in tumour samples in comparison with normal pituitaries. Seven of the eight corticotroph tumours analysed by immunohistochemistry stained positive for p27/kip1, including the intermediate lobe. The only malignant pituitary tumour in the original series showed an absence of staining for p27/kip1. In addition, the three carcinoid tumours studied were negative on immunohistochemistry. Of a further three malignant pituitary tumours assessed, two (including a prolactinoma) were essentially negative, while the third was moderately positive. We conclude that mutations of the p27/kip1 gene, deletions of the 12p13 area or changes in expression, are not a general feature of corticotroph tumours, even those with intermediate lobe characteristics. However, other mechanisms of p27/kip1 inactivation, such as an abnormality at the post-translational level, may be related to more aggressive histological subtypes of ACTH-secreting and possibly other pituitary tumours.


Assuntos
Hormônio Adrenocorticotrópico/metabolismo , Tumor Carcinoide/genética , Proteínas de Ciclo Celular , Proteínas Associadas aos Microtúbulos/genética , Mutação , Neoplasias Hipofisárias/genética , Proteínas Supressoras de Tumor , Adulto , Idoso , Tumor Carcinoide/metabolismo , Síndrome de Cushing/genética , Síndrome de Cushing/metabolismo , Inibidor de Quinase Dependente de Ciclina p27 , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/metabolismo
20.
Clin Endocrinol (Oxf) ; 49(5): 685-9, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10197087

RESUMO

Secondary tumours of any type in the breast are rare. A review of the literature demonstrated only 23 cases of carcinoid tumours with associated breast metastasis, as distinct from primary carcinoid tumours of the breast. Distant metastases from carcinoid tumours are correlated with poor prognosis and survival. Although both primary and metastatic mammary carcinoid tumours are uncommon, the recognition of the true origin of the tumours may be of importance owing to the different clinical management and prognosis of the two conditions. Recently, radionuclide-labelled imaging techniques have been applied to the localization of such lesions, based on isotope uptake by receptors present in these neuroendocrine tumours. We report two new cases of carcinoid tumours with breast metastases, the primaries being in the ileocaecal valve and the bronchus, respectively. The diagnosis of a carcinoid tumour was based on the clinical, biochemical, histopathological and immunostaining features. Furthermore, these patients had both 123I-MIBG and 111In pentetreotide scintigraphy performed. These radionuclides play a useful role in the localization and potentially in the management of carcinoid tumours and their distant metastases.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/secundário , Tumor Carcinoide/diagnóstico por imagem , Tumor Carcinoide/secundário , 3-Iodobenzilguanidina/uso terapêutico , Adulto , Antineoplásicos/uso terapêutico , Neoplasias da Mama/patologia , Neoplasias Brônquicas/patologia , Tumor Carcinoide/patologia , Feminino , Humanos , Neoplasias do Íleo/patologia , Valva Ileocecal , Radioisótopos de Índio , Radioisótopos do Iodo , Octreotida/análogos & derivados , Ácido Pentético/análogos & derivados , Cintilografia , Compostos Radiofarmacêuticos
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