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1.
Eur J Endocrinol ; 136(3): 290-5, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9100554

RESUMO

To investigate the clinical significance of plasma dehydroepiandrosterone sulfate (DHEAS) measurements, 175 patients with histologically confirmed adrenal tumors, 10 cortisol-producing adenomas, 59 aldosterone-producing adenomas, 56 non-hyperfunctioning adenomas, 13 adrenocortical carcinomas, 13 adrenal cysts, and 24 adrenomedullary tumors were studied. Plasma DHEAS levels were expressed as percentage of the mean of sex- and age-matched groups of healthy, normal subjects (DHEAS %). We found that before adrenal surgery, DHEAS % values were significantly reduced in patients with cortisol-producing (mean, 15.2% of control; 95% confidence interval (CI), 9.4-24.7%), non-hyperfunctioning (28.4%; 22.4-36.0%) as well as aldosterone-producing adrenocortical adenomas (55.4%; 47.1-65.1%) compared with controls, while values were normal in patients with adrenal cysts and in those with adrenomedullary tumors. Plasma DHEAS % values exhibited a great variability in adrenocortical carcinomas (mean, 84.0%; 95% CI, 33.2-212.5%). Death from adrenocortical carcinoma was more frequent in patients with high plasma DHEAS % values compared with those with low DHEAS %. During long-term postoperative monitoring, we found that plasma DHEAS levels of patients with aldosterone-producing and non-hyperfunctioning adenomas returned to normal in the second and fourth postoperative year respectively. In patients with cortisol-producing adenomas, plasma DHEAS remained suppressed for as long as 8 years after the operation. These findings show that except in adrenocortical carcinomas and cysts, plasma DHEAS levels are significantly decreased in all groups of adrenocortical tumors, including non-hyperfunctioning and aldosterone-producing tumors. The extent of this decrease and the postoperative persistence of suppressed plasma DHEAS levels may be related to the glucocorticoid production of adrenocortical tumors.


Assuntos
Adenoma/sangue , Adenoma/cirurgia , Neoplasias das Glândulas Suprarrenais/sangue , Neoplasias das Glândulas Suprarrenais/cirurgia , Carcinoma/sangue , Carcinoma/cirurgia , Sulfato de Desidroepiandrosterona/sangue , Adenoma/metabolismo , Neoplasias do Córtex Suprarrenal/sangue , Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/cirurgia , Doenças das Glândulas Suprarrenais/sangue , Doenças das Glândulas Suprarrenais/cirurgia , Neoplasias das Glândulas Suprarrenais/metabolismo , Medula Suprarrenal , Adulto , Idoso , Aldosterona/biossíntese , Carcinoma/metabolismo , Cistos/sangue , Cistos/cirurgia , Feminino , Humanos , Hidrocortisona/biossíntese , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório
2.
J Steroid Biochem Mol Biol ; 66(1-2): 27-33, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9712408

RESUMO

The presence of p53 and tissue transglutaminase (tTG) gene expressions was investigated in human normal and pathologic adrenal tissues with two aims (1) to determine the tissue content of p53 protein, its messenger ribonucleic acid (mRNA) and, especially, tTG mRNA which has not been previously reported and (2) to study possible differences in the coexpression of p53 and tTG in various adrenal disorders. Using Northern blot analysis, p53 and tTG mRNAs were detected in each adrenal tissue examined including 5 normal human adrenals, 6 aldosterone-producing adenomas, 3 Cushing's adenomas, 1 primary nodular adrenocortical hyperplasia causing Cushing's syndrome in an infant, 12 non-hyperfunctioning adrenocortical adenomas, and 4 adrenocortical carcinomas. The results showed a significant positive correlation between these two mRNAs in all adrenal tissues except adrenocortical carcinomas. Compared to normal adrenals, high p53 mRNA levels were observed in aldosterone-producing and Cushing's adenomas and, most markedly, in a tissue from a primary nodular adrenocortical hyperplasia. Also, Cushing's adenomas had significantly higher tTG mRNA contents. Immunohistochemistry for wild-type and mutant p53 protein showed numerous p53 positive cells with a strong nuclear staining in a tissue from a primary nodular adrenocortical hyperplasia, whereas the p53 positive cells were absent, except those with a faint nuclear staining, in all other adrenal tissues. However, all adrenal tissues showed detectable p53 contents by the more sensitive method of luminometric immunoassay (LIA). Using this method, aldosterone-producing adenomas exhibited significantly higher p53 contents than normal adrenal tissues. These observations may support potentially important roles for p53 and tTG in adrenal pathophysiology, especially in mechanisms which influence the evolution and/or progression of aldosterone-producing and Cushing's adenomas and, most probably, hyperplasias.


Assuntos
Glândulas Suprarrenais/patologia , Regulação da Expressão Gênica/genética , Genes p53/genética , Transglutaminases/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Aldosterona/metabolismo , Humanos , Imuno-Histoquímica , Proteínas de Neoplasias/genética , RNA Mensageiro/metabolismo , Proteína Supressora de Tumor p53/análise
3.
J Endocrinol Invest ; 21(11): 753-7, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9972675

RESUMO

The role of p53 tumor suppressor gene in the pathomechanism of adrenal tumors was investigated by measuring p53 protein and its messenger ribonucleic acid (mRNA) in 12 normal human adrenals as well as in 56 adrenal tumors (7 aldosterone-producing adenomas, 5 adrenocortical adenomas causing Cushing's syndrome, 19 non-hyperfunctioning adrenocortical adenomas, 5 adrenocortical carcinomas, 12 pheochromocytomas, 3 myelolipomas, 4 ganglioneuromas and 1 hemangioma). The p53 protein concentration was significantly increased in aldosterone-producing adenomas (394+/-36 pg/mg cytosolic protein, mean+/-SE, vs 266+/-18 in normal human adrenals), whereas the concentration of this protein in Cushing's adenomas, non-hyperfunctioning adrenocortical adenomas, pheochromocytomas, and in all but one adrenocortical carcinomas was similar to that measured in normal human adrenal tissues. One adrenocortical carcinoma tissue showed very high p53 protein content (3000 pg/mg cytosolic protein). By contrast, myelolipomas (23+/-20) ganglioneuromas (43+/-15) and a hemangioma (11 pg/mg cytosolic protein) had very low p53 protein content. Northern blot analysis revealed the presence of p53 mRNA in each adrenal tissue examined with highest levels in aldosterone-producing and Cushing's adenomas. It is possible that the differences in p53 protein and/or mRNA contents reflect corresponding differences in the pathogenetic importance of p53 alterations in these types of adrenal tumors.


Assuntos
Neoplasias das Glândulas Suprarrenais/química , RNA Mensageiro/análise , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/genética , Adenoma/química , Neoplasias do Córtex Suprarrenal/química , Neoplasias das Glândulas Suprarrenais/genética , Aldosterona/biossíntese , Northern Blotting , Síndrome de Cushing/metabolismo , Ganglioneuroma/química , Genes p53 , Hemangioma/química , Humanos , Mielolipoma/química , Feocromocitoma/química
4.
J Endocrinol Invest ; 23(5): 287-94, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10882146

RESUMO

Patients with non-hyperfunctioning adrenal adenomas often have an increased plasma 17-hydroxyprogesterone response to ACTH stimulation. The effects of adrenal surgery on this abnormality have rarely been investigated. One hundred and sixty-one patients with unilateral adrenal tumors (non-hyperfunctioning adenomas, 78; cortisol-producing adenomas, 8; aldosterone-producing adenomas, 37; adrenal cysts, 12; pheochromocytomas, 26) were studied. Patients before and after adrenal surgery as well as 60 healthy subjects underwent an ACTH stimulation test using 2 mg synthetic ACTH(1-24) (Cortrosyn Depot, Organon). Basal and ACTH-stimulated plasma 17-hydroxyprogesterone and cortisol concentrations are reported. Before adrenal surgery, the basal plasma 17-hydroxyprogesterone concentrations were normal in patients with all types of tumors. However, the ACTH-stimulated plasma 17-hydroxyprogesterone levels were abnormally increased in 53% and 31% of patients with non-hyperfunctioning adenomas and aldosterone-producing adenomas, respectively. In addition, a few patients with adrenal cysts and pheochromocytomas also showed an increased ACTH-stimulated 17-hydroxyprogesterone response. After unilateral adrenalectomy, this hormonal abnormality disappeared in most, although not all patients with adrenal tumors. In patients with non-hyperfunctioning adrenal tumors, ACTH-stimulated plasma 17-hydroxyprogesterone and cortisol concentrations significantly correlated with the size of the tumors. These results firmly indicate that the tumoral mass itself may be responsible for the increased plasma 17-hydroxyprogesterone and cortisol responses after ACTH stimulation in patients with non-hyperfunctioning and hyperfunctioning adrenal adenomas.


Assuntos
17-alfa-Hidroxiprogesterona/sangue , Neoplasias das Glândulas Suprarrenais/fisiopatologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia , Cosintropina , Hidrocortisona/sangue , Adenoma/patologia , Adenoma/fisiopatologia , Adenoma/cirurgia , Adolescente , Neoplasias das Glândulas Suprarrenais/patologia , Adulto , Idoso , Aldosterona/biossíntese , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Feocromocitoma/patologia , Feocromocitoma/fisiopatologia , Feocromocitoma/cirurgia
5.
Eur J Biochem ; 250(2): 467-75, 1997 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9428700

RESUMO

Energy charge controls intermediary metabolism and cellular regulation. Here we show that inhibition of energy conservation at the level of glucose uptake, glycolysis, citric acid cycle, and oxidative phosphorylation induces cell death, leading to fragmentation of DNA into an oligonucleosomal ladder and morphological changes typical for apoptosis. Bcl-2, the prototype of oncogenes that suppress cell death, efficiently inhibits apoptosis induced by metabolic inhibitors. Bcl-2 does not antagonize the inhibitory potential of mitochondrial inhibitors, and cannot prevent or delay the decrease of the cellular ATP level subsequent to metabolic inhibition. Thus, we propose that Bcl-2 blocks apoptosis at a point downstream of the collapse of the cellular-energy homeostasis.


Assuntos
Trifosfato de Adenosina/análise , Apoptose/efeitos dos fármacos , Metabolismo Energético , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Animais , Linhagem Celular , Transporte de Elétrons , Glicólise , Camundongos , Mitocôndrias/metabolismo
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