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

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

ACTH independent bilateral macronodular adrenocortical hyperplasia (AIMAH) is associated with autonomous hypercortisolism. We report six cases of AIMAH, in which immunohistochemical studies on steroidogenic enzymes (P450scc, 3 beta HSD, P450c21, P450c17, P450c11) were performed on surgically resected adrenal glands. In situ hybridization studies of P450c17 were performed in two cases in order to localize the sites of steroidogenesis. Immunoreactivity to P450scc, P450c21, and P450c11 was observed in both clear and compact cortical cells, with compact cells displaying more intense staining, as reported in Cushing's adenoma and ACTH dependent bilateral adrenocortical hyperplasia. Immunoreactivity to P450c17 was observed predominantly in small compact cells, whereas that to 3 beta HSD occurred exclusively in clear cortical cells. In situ hybridization also demonstrated that P450c17 was localized in small compact cortical cells. This differential expression of 3 beta HSD and P450c17 in clear and compact cortical cells has been observed only in AIMAH among adrenocortical disorders. This ineffective corticosteroidogenesis may contribute to the relatively low production of cortisol. AIMAH should therefore be considered as a distinct subtype of primary adrenocortical Cushing's syndrome.
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PMID:ACTH-independent macronodular adrenocortical hyperplasia: immunohistochemical and in situ hybridization studies of steroidogenic enzymes. 800 46

"Nonfunctioning" adrenal adenomas are often diagnosed in patients without recognizable clinical symptoms of adrenocortical hyperfunction. The objective of this study was to determine directly the steroidogenic activity of such adenomas (n = 12) and compare them histologically and functionally to normal human adrenals (n = 6) and aldosterone-producing adenomas (n = 15). The histological appearances of nonfunctioning and aldosterone-producing adenomas were surprisingly similar. Nonfunctioning adrenal adenomas expressed all mRNAs of P450scc, P450c17, P450c21, adrenodoxin, and adrenodoxin reductase with relative levels comparable to those found in normal adrenals. Consistent with their hormone-producing nature, these adenomas had cortisol and aldosterone contents as high as those in normal adrenal tissues, a significantly (P < 0.05) increased 17-hydroxyprogesterone content, and a disproportionally low expression of P450c21 mRNA compared to aldosterone-producing adenomas. Cells isolated from both aldosterone-producing and nonfunctioning adrenal adenomas exhibited highly ACTH-sensitive cortisol and aldosterone production, suggesting again the presence of both zona glomerulosa-like and zona fasciculata-like steroidogenesis in these adenoma tissues. These results indicate that so-called nonfunctioning adrenal adenomas are not without steroidogenic activity. Therefore, the assumption that adrenal adenomas are entirely nonfunctioning in the absence of recognizable hormonal hyperfunction may not be correct.
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PMID:Expression of steroidogenic enzyme messenger ribonucleic acids and corticosteroid production in aldosterone-producing and "nonfunctioning" adrenal adenomas. 837 Jun 88

We report clinical findings and steroidogenic activities in adrenal tissues in 2 cases of AIMAH. Endocrine studies revealed an undetectable level of plasma ACTH and a diminished circadian rhythm of plasma cortisol. A significant increase in plasma cortisol levels in response to ACTH stimulation was observed in both cases. After the administration of metyrapone in one case, urinary excretion of 17-hydroxycorticosteroid (17-OHCS) significantly increased, although the plasma ACTH level did not respond. Computed tomography showed large masses in both adrenal glands, and bilateral uptake was identified on adrenal scintigraphy. The totals for the bilateral adrenal glands were 98 g and 105 g, respectively, and the left adrenal was larger than the right in both cases. Steroid content in the nodules measured by high performance liquid chromatography (HPLC) showed that the cortisol content was definitely lower than that in cortisol-producing adenoma (CPA) and even in normal adrenals. The activities of cytochrome P450c17, P450c21 and P450c11 were evaluated in one case, and all of them were reduced in the nodules. Especially that of P450c17 was remarkably reduced. These data suggest that cortisol production in AIMAH is inefficient, and that the cause of Cushing's syndrome may be related to the marked increase in the number of cells or bulk of the tumor.
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PMID:ACTH-independent macronodular adrenocortical hyperplasia (AIMAH): report of two cases and the analysis of steroidogenic activity in adrenal nodules. 915 16

A 48-year-old woman with Cushing's syndrome due to bilateral adrenocortical adenomas is reported. The patient presented with a typical Cushingoid appearance. The serum cortisol level was elevated with loss of the diurnal rhythm and the plasma adrenocorticotropic hormone (ACTH) level was undetectable. Dynamic testing showed no suppression of urinary 17-OHCS by high-dose dexamethasone and no stimulation by metyrapone. An abdominal computed tomography (CT) scan showed bilateral adrenal tumors. Bilateral adrenalectomy was performed. The right adrenal gland contained a tumor that was encapsulated and consisted mainly of compact cells. The surrounding cortex was atrophic. The left adrenal gland contained an encapsulated tumor composed predominantly of clear cells. There were numerous small adrenocortical nodules in the surrounding cortex. Immunohistochemical analysis of steroidogenic enzymes (P450scc, 3beta-HSD, P450c21, P450c17 and P450c11) was performed. Immunoreactivity of all the enzymes was intense in the compact cells of the right adrenocortical adenoma, while the adjacent non-neoplastic cortex was negative for the enzymes. In the left adrenal tumor, the immunoreactivity of 3beta-HSD was intense, while that of P450c17 was weak. In the adrenocortical nodules, 3beta-HSD activity was sporadically observed. G protein genes encoding Gs alpha and Gi2 were examined for activating mutations at codons 201 and 227 (Gs alpha) and codons 179 and 205 (Gi2 alpha) in the bilateral adrenal tumors, but no mutations were found. The bilateral adenomas of this patient showed marked differences in microscopic and immunohistochemical studies, suggesting that the capacity of steroidogenesis differs between the right and left tumors.
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PMID:Cushing's syndrome due to bilateral adrenocortical adenomas with different pathological features. 939 54

The steroidogenic activities in non-hyperfunctioning adrenal adenoma (NHFA) have not yet been fully examined. Steroid content both in adenoma and its non-tumorous adjacent adrenal tissue was measured by the HPLC system in 8 cases of NHFA and 2 cases of preclinical Cushing's syndrome (PCS). Activities of cytochrome P450c17alpha, P450c21, P450c11beta, P450c18 and aldosterone-synthesizing enzyme (P450aldo) were also determined by the enzyme reconstitution system. Steroid content in NHFA varied but no significant difference was seen between NHFA and normal control adrenals. Activities of all P450s except P450aldo were confirmed in NHFA, but they were almost equivalent to those in normal control adrenals. As no significant difference between NHFA and normal controls was observed in either steroid contents or P450s activities, the steroidogenic activity of NHFA is considered to be comparable to that of normal adrenals.
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PMID:The analysis of steroidogenic activity in non-hyperfunctioning adrenocortical adenoma. 946 19

Twenty-one hydroxylase (P450c21) is a key enzyme essential for normal zona glomerulosa and fasciculata function. Recently, 21-hydroxylase deficiency has been implicated in the pathogenesis of adrenocortical tumors. Therefore, we investigated the mutational spectrum of the CYP21B gene and the messenger RNA expression of P450c21 in six aldosterone-producing adenomas, seven cortisol-producing adenomas, two nonfunctional incidentally detected adenomas, and four adrenal carcinomas. DNA from leukocytes and tumors was amplified by PCR using primers specific for the CYP21B gene. The 10 exons, intron 2, intron 7, all other exon/intron junctions, and 380 bp of the promoter region of CYP21B were automatically sequenced. Poly(A) RNA was extracted from tumor tissue, dot blotted on a nylon membrane, and hybridized with 32P-labeled P450 side-chain cleavage, P450 17-alpha-hydroxylase, and P450c21 complementary DNA probes. We detected heterozygous germline mutations (exon 7, Val 281Leu) in two patients, one with a cortisol-producing adenoma and the other with an androgen-secreting adrenocortical carcinoma. A somatic, heterozygous microdeletion was found in exon 3 of one aldosterone-producing adenoma. The P450c21 gene expression correlated with the clinical phenotype of the tumor, with low P450c21 messenger RNA expression in nonfunctional adenomas (18.8%, 1.5%) compared with high P450c21 expression in aldosterone- and cortisol-producing adenomas (84 +/- 8% and 101 +/- 4%, respectively, vs. normal adrenals, 100 +/- 10%). In conclusion, the prevalence of heterozygous germline mutations in the CYP21B gene was higher in patients with adrenocortical tumors (11%; 95% confidence interval, 1-34%) than in the general European population (2%; 95% confidence interval, 1.93-2.06%), but this difference is questionable because of the low number of subjects in our series. The pathophysiological significance of this finding in the presence of one normal CYP21B gene seems to be low, suggesting that 21-hydroxylase deficiency is not a major predisposing factor for adrenal tumor formation.
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PMID:Steroid 21-hydroxylase mutations and 21-hydroxylase messenger ribonucleic acid expression in human adrenocortical tumors. 966 49

We report a rare case of virilizing adrenocortical adenoma complicated with Cushing's syndrome, thyroid papillary carcinoma and hypergastrinemia. A 45-year-old woman had a history of amenorrhea for 10 years, hypertension for 8 years, and diabetes mellitus for 3 years. Physical examination showed a masculinized woman with severe hirsutism, male-like baldness, deep voice, acne in the precordia, and clitorism. Plasma testosterone, DHEA-S and urinary 17-KS were high, and plasma cortisol level was it at the upper limit of the normal range, but it did not show a diurnal rhythm nor was suppressed by 2 and 8 mg of dexamethasone. Abdominal CT scan showed a left adrenal tumor (4.5 cm in size). Adrenal scintigram revealed uptake of the tracer on the left side, and plasma cortisol concentration was high in a blood sample from the left adrenal vein. Left adrenalectomy was performed. Histopathological features of resected adrenal tumor were consistent with those of adrenocortical adenoma, consisting of tumor cells with eosinophilic compact cytoplasm. Immunohistochemical staining for steroidogenic enzymes showed reactivity for P450sec, 3 beta-HSD, P450c17, P450c21 and P450c11. Plasma testosterone and cortisol levels decreased to the normal range postoperatively. The patient was also found to have a papillary thyroid carcinoma and hypergastrinemia. Our patient is a rare case of virilizing adrenocortical adenoma associated with Cushing's syndrome, thyroid papillary carcinoma, and hypergastrinemia.
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PMID:Virilizing adrenocortical adenoma with Cushing's syndrome, thyroid papillary carcinoma and hypergastrinemia in a middle-aged woman. 1280 38

Nonclassical form of 21-hydroxylase deficiency (NC 21OHD) as a frequent variant on the milder end of the disease spectrum has been widely acknowledged, but its potential contribution to adrenocortical tumorigenesis has not been fully elucidated. We report a 66-year old male case of bilateral adrenocortical incidentaloma, associated with partial 21OHD without any episodes of hypoadrenocorticism in his past history. He was demonstrated to be a compound heterozygous mutant of CYP21A2 gene (IVS2-13A/C>G/I172N). The two tumors in the left adrenal, which were interpreted as myelolipoma by imaging studies, were followed by sequential observation, whereas the contralateral large solid tumor associated with inhomogeneous radiological appearance was subsequently removed. The resected tumor was diagnosed an adrenocortical adenoma, which was devoid of P450c21 immunoreactivity. 21OHD is often associated with benign adrenocortical tumors, but bilateral adrenal tumors with heterogeneous components in both adrenals have not been reported to the best of our knowledge.
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PMID:A male case of nonclassical 21-hydroxylase deficiency first manifested in his sixties with adrenocortical incidentaloma. 1832 73


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