Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007095 (carcinoid)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The concentrations of immunoreactive (IR) corticotropin-releasing hormone (CRH) in 218 neuroendocrine tumors were determined by CRH radioimmunoassay. The tumors examined were 86 pancreatic endocrine tumors (PET), 22 neuroblastic tumors (NBT), 26 carcinoid tumors (CA), 24 pheochromocytomas (PHEO), 40 small cell lung carcinomas (SCLC) and 20 medullary thyroid carcinomas (MTC). IR-CRH was detectable in 21 neuroendocrine tumors (10 PET, four NBT, three CA, two PHEO and two SCLC) at levels of 10-2,700 ng/g wet weight (9.6%). The 21 patients with these CRH-producing tumors showed no clinical symptoms suggestive of Cushing's syndrome. The levels of plasma IR-CRH extracted by immunoaffinity chromatography were < 7.5 pg/ml in five normal subjects and a patient with a neuroblastic tumor containing 55 ng/g wet weight IR-CRH, but in a patient with a thymic carcinoid tumor containing 1,000 ng/g wet weight IR-CRH, the plasma level was elevated to 180 pg/ml. This patient did not have Cushing's syndrome nor an elevated plasma adrenocorticotropic hormone (ACTH) level. The concentrations of nine peptides (growth hormone-releasing hormone, somatostatin, ACTH, calcitonin, gastrin-releasing peptide, glucagon, vasoactive intestinal peptide, neuropeptide tyrosine and pancreatic polypeptide) were determined in extracts of the 21 IR-CRH-producing tumors. Some of these peptides were frequently found to be produced concomitantly with CRH. The results indicate IR-CRH to be produced by various neuroendocrine tumors, but Cushing's syndrome, due to the CRH, to be very rare. The results also show that CRH-producing tumors produce multiple hormones.
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PMID:Production of immunoreactive corticotropin-releasing hormone in various neuroendocrine tumors. 135 72

Neuropeptide Y (NPY) and its flanking peptide (CPON) were measured in extracts of pheochromocytomas (n = 26), ganglioneuroblastomas (n = 8), and other tumors (n = 95) and plasma (n = 38). NPY was present in high concentrations in the majority of the pheochromocytomas, but was absent in 3 tumors. Similar concentrations of NPY were measured using N- and C-terminal-directed antisera, and there was a good correlation between the concentrations of NPY immunoreactivity and CPON immunoreactivity in the same extracts. Gel permeation chromatography revealed that the separate peptides NPY and CPON were the major products. No significant amounts of a large mol wt precursor containing both immunoreactivities was found. Among the other tumors, 6 of 22 carcinoid tumors, 2 of 2 somatostatinomas, and 3 of 18 insulinomas contained detectable amounts of NPY. Plasma NPY concentrations were very low in normal subjects, and extraction and a 10-fold concentration step were necessary to establish the normal range (0.35-1.25 pmol/L). Plasma NPY concentrations were detectable in unextracted plasma (10 pmol/L) in 50% of patients with pheochromocytomas, but no correlation was found between plasma NPY concentrations and either plasma norepinephrine or epinephrine concentrations. These results indicate that 1) NPY and CPON are present in most, but not all, pheochromocytomas and ganglioneuroblastomas; 2) secretion of NPY immunoreactivity may be independent of that of catecholamines; 3) CPON immunoreactivity is present in plasma of patients with pheochromocytoma; 4) the majority of NPY and CPON immunoreactivities appears to be in the form of the separate free peptide, and there is very little precursor containing both immunoreactivities expressed in these tumors; and 5) NPY immunoreactivity is present in a variety of other endocrine tumors.
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PMID:Neuropeptide Y and its flanking peptide in human endocrine tumors and plasma. 357 23