Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to elucidate the steroidogenesis of clinically nonfunctioning adrenocortical adenoma, we studied the aldosterone, cortisol (F) and dehydroepiandrosterone (DHEA) content and the expression of mRNA of cytochrome P450 for side chain cleavage (P450scc), 17 alpha-hydroxylase (P450c17). 21-hydroxylase (P450c21) and 11 beta-hydroxylase (P450c11) in four clinically nonfunctioning adrenocortical adenomas discovered incidentally in asymptomatic patients (Cases 1, 2, 3 and 4). The results were compared with those in normal adrenal glands. In the adenomas from cases 1 and 2, the abundance of steroidogenic P450s mRNA were similar to those in normal adrenal glands, except P450c11 mRNA expression in the adenoma from case 1 which was slightly higher than normal. The steroid content was normal level, except for higher F in the adenoma from case 1 and lower aldosterone in case 2 adenoma than normal. The adenoma from case 3 contained much less P450scc, P450c17 and P450c21 mRNA, while the amount of P450c11 mRNA was slightly greater than in normal adrenals. The adenoma showed normal aldosterone, high F and low DHEA content compared with normal adrenal glands. In the adenoma from case 4, the accumulation of all four P450 mRNAs decreased, whereas aldosterone, F and DHEA content in the adenoma was similar to that of normal adrenal glands. These data indicated that nonfunctioning adrenocortical adenoma showed similar or decreased expression of steroidogenic P450 mRNAs that the normal adrenal gland. This decreased expression of steroidogenic P450 mRNAs may be at least partly concerned with the absence of clinical symptoms in patients with nonfunctioning adenoma.
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PMID:Disordered expression of adrenal steroidogenic P450 mRNAs in incidentally discovered nonfunctioning adrenal adenoma. 153 42

A 60-year-old woman was evaluated for persistently elevated serum testosterone concentrations after bilateral ovariectomy. Her serum cortisol, androstenedione, dehydroepiandrosterone sulphate and 17-hydroxyprogesterone levels were normal, and decreased after dexamethasone administration. Those of testosterone (17.8-18.4 nmol/l) were remarkably high (normal range 0.7-2.8 nmol/l), were not suppressed by dexamethasone, but clearly increased after hCG administration (up to 128 nmol/l). Computed tomography revealed an adenoma in the right adrenal gland and adrenal scintigraphy under dexamethasone suppression visualized this adenoma. A right adrenalectomy was performed. (1) The tumour was histologically and ultrastructurally adrenocortical adenoma of zona reticularis cell type. (2) The adenoma tissue contained hCG receptors (198 fmol/g). (3) During tissue culture both ACTH and hCG were capable of maintaining its testosterone production, which was attenuated with time without stimulation. (4) The adenoma tissue did not elaborate 21-hydroxylated steroids in contrast to normal adrenal tissue. Thus the aberrant endocrine behaviour of this gonadotrophin-responsive testosterone-secreting adenoma of adrenal zona reticularis cell origin can be explained by ectopic functional hCG receptors and the lack of 21-hydroxylase activity.
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PMID:Testosterone-secreting virilizing adrenal adenoma with human chorionic gonadotrophin receptors and 21-hydroxylase deficiency. 184 85

Adrenocortical adenoma incidentally found in a 37-yr-old female patient, with simple virilizing form of 21-hydroxylase deficiency, was studied. Cultured adenoma cells revealed excessive secretion of 17 alpha-hydroxyprogesterone in response to 10(-8) M ACTH, compared with those of 11-deoxycortisol and cortisol, which indicated impaired activity of the 21-hydroxylase. To elucidate the molecular mechanisms of this defective 21-hydroxylase in the adenoma, we analyzed the gene encoding specific cytochrome P450 (P450c21) for steroid 21-hydroxylation and its expression. DNA and RNA were extracted from the adrenal adenoma and were hybridized with a probe of human P450c21 gene, by Southern and Northern blot analysis. In Southern blot analysis with Taq I, Bgl II or Bam HI, there was no difference between the pattern of restriction fragments in DNA from the adenoma and normal peripheral leucocytes. Northern blot analysis of the adenoma showed the same size of P450c21 mRNA as in the normal adrenal gland, but the amount was low--about a half that of the normal adrenal. In Western blot analysis with polyclonal antibody to P450c21, only a small amount of P450c21 protein was detected in the adenoma, although it was found to be of the same molecular weight as that in the normal adrenal gland. In view of these findings it is conceivable as one of possibilities that a mild and small mutation in the structural or promotor region of the P450c21 gene may cause the decreased 21-hydroxylase activity in this adenoma.
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PMID:Decreased levels of steroid 21-hydroxylase [P450(c21)] and its mRNA in an adrenocortical adenoma associated with 21-hydroxylase deficiency. 210 89

The presence of adrenal nodules in patients with congenital adrenal hyperplasia seems to be relatively frequent but is seldom reported. We observed such nodular formations in 3 women and 2 men aged from 19 to 71 years. Four patients had enzyme deficiency revealed in childhood (3 were deficient in 21-hydroxylase and 1 in 11-hydroxylase); the fifth patient had a virilizing form of an unrecognized 21-hydroxylase deficiency. In 3 patients the nodular formations had a diameter of 10 millimetres or less. In the other 2 patients the diameter was greater than 30 millimetres, and an adrenocortical adenoma was found at surgery. In one case a preoperative increase of medical treatment resulted in partial regression of the nodules. Our findings show that young subjects may have adrenal nodules, and their dependence on ACTH is discussed. We also discuss the possible influence of these nodules on the difficulty of medical treatment, the need for a life-long therapy and the necessity to look for a congenital adrenal hyperplasia when confronted with an "incidentaloma".
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PMID:[Nodular adrenomegalies in congenital adrenal hyperplasia in adults. Implications]. 217 90

Modes of inhibition and binding of ketoconazole, an orally antimycotic agent, to NADPH-cytochrome P-450 dependent enzymes were investigated using subcellular fractions of human and rat testes, human adrenocortical adenoma tissue and rat adrenals and livers. Ketoconazole competitively inhibited the activities of steroid 17 alpha-hydroxylase and C17-20 lyase in rat and human testes, 16 alpha-hydroxylase in human testes and 21-hydroxylase in rat adrenal glands. Ki values were in the order of 10(-8)M for human testicular enzymes, while the order was 10(-7)-10(-6) M for rat adrenal and testicular enzymes. Kinetic studies indicated that ketoconazole bound to cytochrome P-450 and not to other components of monooxygenase systems. Spectrophotometric studies also revealed direct binding of ketoconazole to cytochrome P-450 component by inducing type II difference spectra in all tissue preparations examined, indicating that ketoconazole is possibly a universal inhibitor of NADPH-cytochrome P-450 dependent monooxygenases which are involved in metabolism of many substances including steroids, toxins, carcinogens and others.
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PMID:Ketoconazole as a possible universal inhibitor of cytochrome P-450 dependent enzymes: its mode of inhibition. 311 39

We report a case of congenital adrenal hyperplasia complicated by a right adrenal adenoma. The congenital adrenal hyperplasia was confirmed by extremely high levels of basal serum 17 alpha-hydroxy-progesterone and urinary pregnantriol as well as an exaggerated response of 17 alpha-hydroxyprogesterone to adrenocorticotropic hormone. On roentogenographic examinations and an echogram a huge calcified tumor was seen in the right adrenal gland. Histological findings indicated an adrenocortical adenoma. Culture of the tumor cells showed an accentuated response in the ratio of 17 alpha-hydroxy-progesterone to desoxycortisol with adrenocorticotropic hormone as a stimulator, suggesting that such adenoma cells also lack 21-hydroxylase activity. Our study clearly demonstrates that tumor cells have the same steroidogenic lesions as hyperplasia.
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PMID:Adrenocortical tumor in a patient with untreated congenital adrenocortical hyperplasia owing to 21-hydroxylase deficiency: characterization of steroidogenic lesions. 341 4

Short stature, severe hirsutism, an enlarged clitoris and lack of vaginal introitus were manifest in a 55-year-old female karyotype, male phenotype patient brough up as a female. The hormone profile suggested congenital adrenal hyperplasia due to 21-hydroxylase adrenal enzyme deficiency. Follicle-stimulating hormone and luteinizing hormone levels were 122.5 and 100.3 mIU/ml, respectively, within the normal range for a postmenopausal woman. Computerized axial tomography revealed a large cystic tumor connected to the right adrenal gland. Both the right adrenal gland and the cyst were removed. The adrenal cortex showed diffuse hyperplasia and contained a well-defined nodule. The case was interesting because we had the opportunity of examining a patient of advanced age with untreated congenital adrenal hyperplasia and because of the very rare combination of adrenogenital syndrome with nodular hyperplasia and a cystic tumor, which was most probably a degenerated adenoma.
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PMID:Congenital adrenal hyperplasia diagnosed in a middle-aged woman. 696 8

We examined both activities and amounts of steroidogenic cytochrome P-450s at the posttranslational protein level and steroid contents in the adrenocortical adenoma from patients with primary aldosteronism and Cushing's syndrome. Aldosterone synthase cytochrome P-450 (human P-450aldo) was detected in the tumour portion of aldosterone-producing adenoma, but not in the normal control adrenals, at the protein level. Neither the activities nor the amounts of other P-450s in the tumour portion of aldosterone-producing adenoma were significantly different from those in the non-tumour portion in the adenoma and the normal control adrenals. The aldosterone content was significantly elevated, while the androstenedione content was significantly decreased in the tumour portion of the adenoma compared with that in the normal control adrenals. In Cushing's syndrome, both the activities and amounts of P-450(17 alpha) and P-450c21 were significantly elevated in the tumour portion compared with the non-tumour portion of the adenoma and the normal control adrenals, while those of P-450scc and P-450(11 beta) in the tumour portion were not significantly different from the normal control adrenals. The cortisol content was significantly elevated, while the amounts of aldosterone and 18-hydroxydeoxycorticosterone in the tumour portion of the adenoma were significantly decreased compared with those in the normal control adrenals. These results demonstrate that overexpression of P-450aldo in aldosterone-producing adenoma, and those of P-450(17 alpha) and P-450c21 in cortisol-producing adenoma may play some role in the pathogenesis of primary aldosteronism and Cushing's syndrome, respectively.
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PMID:Significance of steroidogenic enzymes in the pathogenesis of adrenal tumour. 848 Apr 73

A case of an adrenal incidentaloma in a 57-year-old man with silent 21-hydroxylase deficiency is reported. Abdominal computed tomography revealed a right adrenal tumour of 6cm in diameter. There was no evidence of adrenal hormone excess. However, after surgical removal of the adrenal tumour, the patient developed acute adrenal insufficiency. Adrenocortical function has remained low ever since surgery. Pathological examination of the tumour revealed a cortical adenoma. On the basis of increased plasma renin activity and serum 17 alpha-hydroxyprogesterone concentration and decreased 21-hydroxylase activity of the adenoma tissue, the patient was diagnosed as having systemic 21-hydroxylase deficiency. There are two possible mechanisms for the persistent adrenal insufficiency; first the residual left adrenal gland may have been originally hypo-functioning for some reason and, second, the left gland may have lost the ability to regenerate following prolonged suppression by the adenoma. In cases of adrenal incidentalomas with 21-hydroxylase deficiency, the indications for surgical removal should be carefully considered.
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PMID:A case of silent 21-hydroxylase deficiency with persistent adrenal insufficiency after removal of an adrenal incidentaloma. 923 Oct 63

It is known that some patients with primary aldosteronism show postoperative hyperkalemia, which is due to inability of the adrenal gland to secrete sufficient amounts of aldosterone. However, hyperkalemia is generally neither severe nor prolonged, in which replacement therapy with mineralocorticoid is seldom necessary. We report a case of a 46-year-old woman with an aldosterone-producing adenoma associated with severe postoperative hyperkalemia. After unilateral adrenalectomy, the patient showed episodes of severe hyperkalemia for four months, which required not only cation-exchange resin, but also mineralocorticoid replacement. Plasma aldosterone concentration (PAC) was low, although PAC was increased after rapid ACTH test. Histological examination indicated the presence of adrenocortical tumor and paradoxical hyperplasia of zona glomerulosa in the adjacent adrenal. Immunohistochemistry demonstrated that the enzymes involved in aldosterone synthesis, such as cholesterol side chain cleavage (P-450scc), 3beta-hydroxysteroid dehydrogenase (3beta-HSD), and 21-hydroxylase (P-450c21), or the enzyme involved in glucocorticoid synthesis, 11beta-hydroxylase (P-450c11beta), were expressed in the tumor, but they were completely absent in zona glomerulosa of the adjacent adrenal. These findings were consistent with the patterns of primary aldosteronism. Serum potassium level was gradually decreased with concomitant increase in PAC. These results suggest that severe postoperative hyperkalemia of the present case was attributable to severe suppression of aldosterone synthesis in the adjacent and contralateral adrenal, which resulted in slow recovery of aldosterone secretion. It is plausible that aldosterone synthesis of adjacent and contralateral adrenal glands is severely impaired in some cases with primary aldosteronism, as glucocorticoid synthesis in Cushing syndrome.
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PMID:A case of aldosterone-producing adenoma with severe postoperative hyperkalemia. 1034 17


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