Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the past, pituitary tumours that produce one or more of the glycoproteins (TSH, LH, FSH and alpha subunit) were thought to be rare. However, using modern immunocytochemical and molecular biology techniques, these tumours are being recognized with increasing frequency. Many of these tumours produce glycoprotein alpha and beta subunits in addition to intact glycoproteins. Hormone production is often low compared with tumour size, and serum hormone levels may not be elevated in these patients. Tumours that produce the gonadotrophins (LH or FSH) or alpha subunit account for the majority of clinically non-functioning pituitary adenomas. They do not cause a specific clinical syndrome, and usually present with symptoms of a large mass lesion and/or hypopituitarism. Optimal treatment of these tumours is often difficult. The initial approach is usually transsphenoidal surgery, followed by radiation therapy if there are symptoms due to residual tumour. Medical therapy of gonadotrophin and alpha subunit tumours may include the use of dopamine agonists or somatostatin analogues, although neither has been shown to consistently decrease tumour size. Preliminary trials with experimental GnRH antagonists suggest that these agents may be useful as adjuvant therapy of gonadotrophin tumours. Tumours that produce TSH are rare. Patients present with hyperthyroidism, which is often misdiagnosed as Graves' disease, as well as with symptoms of a pituitary mass lesion. Almost all TSH tumours secrete excess amounts of free alpha subunit. Optimal treatment of these tumours includes transsphenoidal surgery, followed by radiation therapy for residual tumour. The somatostatin analogue octreotide is effective in reducing excess TSH secretion from these tumours, and causes a reduction in tumour volume in a significant minority of patients.
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PMID:Glycoprotein-secreting pituitary adenomas. 762 88

Screening was performed in 130 consecutive patients with apparently sporadic neuroendocrine tumors (NET) to assess the prevalence of multiple endocrine neoplasia type 1 (MEN1) and hormonal production. Screening for MEN1 included measurement of serum calcium and PTH [PTH-(1-84)], gastrin, PRL, and insulin-like growth factor type I (IGF-I) levels. MEN1 genetic testing was performed in patients with two components of the MEN1 syndrome. Screening for hormonal production included measurement of serum neuron-specific enolase (NSE), calcitonin (CT), glycoprotein alpha-subunit (GP alpha), hCG beta-subunit (free hCG beta), and somatostatin levels. Twenty-four-hour urinary free cortisol (UFC) and 5-hydroxyindolacetic acid (5-HIAA) determinations were also performed. Four patients had hyperparathyroidism, none of whom had pituitary or familial disease. Hyperprolactinemia was compatible with a pituitary disease in one patient. No acromegalic feature or any increase in IGF-I was found. Hypergastrinemia, compatible with an associated pancreatic NET, was found in one patient. Genetic screening of the MEN1 gene was performed in five of the six patients with two components of the MEN1 syndrome. A nonsense mutation (Arg108stop) was identified in the tumor of one patient. Elevated NSE, 5-HIAA, CT, GP alpha, free hCG beta, SMS, and nonsuppressible UFC were found in 47%, 46%, 14%, 19%, 12%, 3%, and 6% of NET patients, respectively. Production of CT, GP alpha, and free hCG beta was highly related to the primary site: all but two of these secretions originated in foregut NET. 5-HIAA secretion was found in 27% of foregut-derived and 85% of midgut-derived NET. In conclusion, MEN1 is a rare event in patients presenting with apparently sporadic NET. It occurred mainly in foregut NET and should be screened for by serum calcium and PTH-(1-84) measurements. Routine hormonal measurements should depend on the primary site. NSE, 5-HIAA, CT, and alphaGP should be routinely measured in foregut-derived NET; only serum NSE and 5-HIAA measurements are recommended in midgut-derived NET.
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PMID:Screening for multiple endocrine neoplasia type 1 and hormonal production in apparently sporadic neuroendocrine tumors. 992 64