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)

Inhibin alpha and beta A subunit messenger ribonucleic acid (mRNA) levels were measured quantitatively by reverse transcription-polymerase chain reaction (RT-PCR) in human pituitary adenomas. The inhibin alpha subunit mRNA levels were undetectably low in cultured adenoma tissues, but beta A mRNA were 0.383 +/- 0.074 in 3 GH adenomas, 0.672 +/- 0.140 in 3 prolactinomas and 0.957 +/- 0.414 molecules/cell in 3 non-functioning adenomas. The addition of 10(-8) M activin A decreased the beta A mRNA levels within 4 h in 1 of 3 GH adenomas, 2 of 3 prolactinomas and 2 of 3 non-functioning adenomas, though the decreases were not statistically significant. The results showed an abundance of beta A subunit mRNA compared with alpha subunit mRNA in all human pituitary adenomas and a local role for activin in its own production through inhibin beta A mRNA subunit expression.
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PMID:Inhibin alpha and beta A subunit messenger ribonucleic acids expression in human pituitary adenomas: studies by quantitative reverse transcription-polymerase chain reaction. 888 32

We report an unusual case of a gonadotroph adenoma in a 34-yr-old woman, revealed by a dramatic rise in the plasma estradiol (E2) concentration (26,800 pmol/L; normal, <370), with nonsuppressed FSH and LH levels (4.9 and 2.4 mIU/mL, respectively). The PRL level was 503 ng/mL. The testosterone and progesterone levels were 7 and 17 nmol/L, respectively. The levels of inhibin alpha, inhibin A, and inhibin B were increased compared to normal values in both the follicular (fp) and luteal (lp) phases of the menstrual cycle [inhibin alpha, 1986 IU/L (fp normal, <700; lp normal, <1650); inhibin A, 254 pg/mL (fp normal, <20; lp normal, <120); inhibin B, 246 pg/mL (fp normal, <150; lp normal, <30 lp)]. Pituitary magnetic resonance imaging revealed a huge pituitary adenoma. After transphenoidal surgery, the patient presented with pituitary insufficiency and diabetes insipidus. RT-PCR of the tumor tissue was positive for LHbeta, FSHbeta, alpha-subunit, and PRL. This case is of particular interest because 1) although the E2 level was extremely high, the patient did not present with ascitis, suggesting that chronic elevated E2 does not play a crucial role in the hyperstimulation symptoms; 2) the extreme rise in E2 was related to the cosecretion of FSH and LH, confirming the two-cell two-gonadotropin theory; and 3) the rise in inhibin B is associated with FSH secretion, whereas the rise in inhibin A is probably due to luteinization.
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PMID:A spontaneous and severe hyperstimulation of the ovaries revealing a gonadotroph adenoma. 1048 22

Inhibin normally is produced by ovarian granulosa cells and testicular Sertoli cells. Extragonadal inhibin expression also has been detected in the placenta, pituitary gland, and liver. It may be difficult to make a distinction between adrenal cortical tumors, pheochromocytoma, and metastatic carcinomas including renal cell and hepatocellular carcinoma. Immunohistochemical expression of inhibin alpha-subunit was evaluated to determine whether any usefulness of immunostaining could be found for inhibin alpha-subunit in the differential diagnosis of adrenal glandular lesions. The authors performed immunostaining against inhibin alpha-subunit on 5 cases of normal adrenal gland, 1 case of adrenal cortical hyperplasia, 25 cases of adrenal cortical adenoma, 6 cases of adrenal cortical carcinoma, 21 cases of pheochromocytoma, 8 cases of metastatic carcinoma, and 10 cases of primary renal cell carcinoma. Normal adrenal gland showed a strong immunoreactivity against inhibin alpha-subunit, especially in the inner layer of the adrenal cortex, representing the zona reticularis, but adrenal medulla was negative for inhibin alpha-subunit. Adrenal cortical hyperplasia associated with Cushing's syndrome showed a strong, diffuse immunoreactivity for inhibin alpha-subunit. Immunoreactivity against the inhibin alpha-subunit was identified in all cases of adrenal cortical adenoma and carcinoma, especially in the adrenal cortical neoplasm with Cushing's syndrome, which showed a strong reactivity. However, immunoreactivity was absent in two metastatic carcinomas from the liver and colon and most of the pheochromocytomas, except three cases with weak focal positivity for inhibin alpha-subunit. Four cases of metastatic renal cell carcinoma and 10 cases of primary renal cell carcinoma revealed no immunoreactivity. Metastatic adenocarcinoma from the prostate showed a weak immunoreactivity for inhibin alpha-subunit. Metastatic hepatoblastoma was negative against inhibin alpha-subunit with endogenous biotin blocking. Immunoexpression for inhibin alpha-subunit is useful for making distinction between adrenal cortical tumors, pheochromocytoma, and metastatic carcinoma. Inhibin alpha-subunit may be valuable as part of a diagnostic immunohistochemical panel in adrenal glandular lesions.
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PMID:Immunoexpression of inhibin alpha-subunit in adrenal neoplasms. 1155 49

The human reproductive process is regulated by complex mechanisms that involve many organs, including the brain, gonads and endocrine system. It has been more than 70 years since the name 'inhibin' was used to describe a substance produced in the gonads that negatively regulates pituitary secretion. Inhibin B controls FSH secretion via a negative feedback mechanism. It is a glycoprotein hormone secreted by the Sertoli cells of the testis and granulosa and theca cells of the ovary. Serum inhibin B concentrations are positively related to testicular volume and sperm counts. Current understanding of inhibin physiology and pathology in the human suggests that inhibin B may be of importance as a marker of Sertoli cell function in men with infertility and as a prognostic indicator in women undergoing ovulation induction therapy. Inhibin concentrations are elevated in patients with granulosa cell tumours and in post-menopausal women with mucinous ovarian cancers. Immunoreactivity against the inhibin alpha-subunit was identified in all cases of adrenal cortical adenoma and carcinoma, and levels are suppressed in the malignant prostate disease. This article discusses the structure, regulation and clinical use of inhibin and other related substances.
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PMID:Significance of inhibin in reproductive pathophysiology and current clinical applications. 1597 11

We studied the immunoreactivity of three antibodies--A103, calretinin, and inhibin alpha in destained Papanicolaou (Pap) smears and cell-blocks of 40 fine-needle aspiration biopsy cases of adrenocortical lesions (35 cases of hyperplasia/adenoma and 5 cases of carcinoma). Five cases of carcinoma (4) and melanoma (1) metastases to the adrenal gland and five cases of renal-cell carcinoma were also included for comparison. In benign adrenocortical lesions, A103 staining was noted in 82% of the destained Pap smears and in 92% of cell-blocks. In malignant adrenocortical lesions, A103 staining was noted in 50% of the destained Pap smears and in 80% of cell-blocks. In comparison, calretinin staining was noted in 6% and 50% of destained smears and in 78% and 60% of the cell-blocks of benign and malignant adrenocortical lesions. Inhibin alpha was not positive in any of the smears and showed the lowest level of positivity in the cell-block sections, namely in 11% of the benign lesions and 25% of the malignant lesions. The sensitivity of A103 was 90% on cell-blocks and 74% on smears, that of calretinin 75% on cell-blocks and 11% on smears, and that of inhibin alpha, 13% on cell-blocks alone. The specificity of A103 was lower than the other two makers, 90% vs. 100% because of positivity in metastatic melanoma in the adrenal gland. Our data show A103 to be the immunomarker with the highest sensitivity for identifying cells of adrenocortical origin in destained Pap's smears and cell-block sections with, however, a lower specificity when compared with calretinin and inhibin alpha. Calretinin is comparable in sensitivity with A103 on cell-block sections alone and not on smears. The results of this study suggest that if metastatic melanoma in adrenal gland is not a consideration then A103 is the marker of choice for identifying cells of adrenocortical origin in the limited material available for diagnostic purposes in cytology specimens.
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PMID:Comparison of immunomarkers for the identification of adrenocortical cells in cytology specimens. 1600 49