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)

Prostate-specific antigen (PSA) is a serine proteases produced by prostatic epithelial cells detectable in male serum and seminal plasma. PSA is also expressed in some female tissues and fluids and is increased in hirsute women showing a positive correlation with androgens. Accordingly, it has been suggested that PSA might be a marker of androgen action in women. The aim of this observational study was to assess serum PSA concentration in acro megalic women with active disease, in remission or during somatostatin analogs therapy. Forty-four acromegalic women, 15 with active disease, 10 in remission and 19 under long-acting somatostatin analogs therapy were enrolled in the study; 273 normal women matched for age, body mass index, with no signs of hirsutism, served as controls. Serum PSA, 3a-androstanediol (3alpha-AG), total testosterone (T), DHEAS, LH, FSH and estradiol were assessed. No patient or control had been given estrogen or antiandrogen drugs; no acromegalic women had hyperprolactinemia or hypopituitarism. Serum PSA concentration was significantly higher in acromegalic patients than in control subjects (p < 0.0001). Patients with active acromegaly or under somatostatin analogs therapy had significant higher serum PSA concentration than controls, while patients in remission after adenomectomy did not differ. Serum PSA was detectable in serum of 75% acromegalic women and 45% of controls. In addition 24% of acromegalic women had serum PSA concentrations higher than the mean +/- 2SD of control subjects. Differences in serum PSA levels did not reach statistical significance in the different acromegalic subgroups possibly because of the small number of subjects, but patients with active acromegaly had higher serum PSA levels than patients under somatostatin analogs therapy or in remission. Acromegalic women had significantly higher serum PSA concentrations than controls both before and after menopause (p < 0.01). 3alpha-AG (p < 0.05) and T (p < 0.01) were higher in acromegalic than in control subjects in pre-menopause (PM) but not in post-menopause (M). A correlation was found in the whole group of acromegalic patients between serum PSA and 3a-AG concentrations (r = 0.3, p < 0.01). In conclusion, acromegalic is associated with an increase in serum PSA concentrations as a group, although this increase is observed, at an individual level, in only 24% of cases. Patients whose disease is controlled by somatostatin analogs or has been cured by pituitary adenomectomy tend to have lower serum PSA levels than patients with active disease. M patients tend to have lower PSA values than PM women, consistent with the main androgen control of PSA production. However, the observation that M women still have higher serum PSA levels than controls suggest that in acromegaly PSA is regulated not only by androgens but also by the GH/IGF-I system itself.
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PMID:Serum prostate-specific antigen concentration is increased in acromegalic women. 1550 87

Growth hormone (GH) acts predominantly via insulin-like growth factor-I (IGF-I) expression. Acromegaly is associated with an increased mortality which can be reversed by optimal treatment. Somatostatin analogues are effective adjunctive therapies in patients treated with surgery and/or radiotherapy and result in tumour shrinkage in many patients. Pegvisomant is a GH analogue which inhibits functional dimerization of GH receptors, inhibits GH activity and normalizes IGF-I in over 90% of subjects. Adult GH deficiency is associated with changes in body composition, insulin status, lipid profile and Quality of Life measures. Hypopituitarism is associated with an increased mortality. Replacement with GH has clinically beneficial effects but there are no data on effects on mortality. Taller individuals are at a 20-60 percent increased risk of a range of cancers, an effect that may be mediated via IGFs. These observations suggest that there is an optimal level of circulating GH and IGF-I required to maintain normal health.
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PMID:Growth hormone--from molecule to mortality. 1553 73

Pituitary tumors cause symptoms by secreting hormones (prolactin, PRL, responsible for amenorrhea-galactorrhea in women and decreased libido in men; growth hormone, GH, responsible for acromegaly; adrenocorticotropic hormone, ACTH, responsible for Cushing's syndrome; thyroid-stimulating hormone, TSH, responsible for hyperthyroidism), depressing the secretion of hormones (hypopituitarism), or by mass-related effects (headaches, visual field abnormalities...). All patients with pituitary tumors should be evaluated for gonadal, thyroid and adrenal function as well as PRL and GH secretion. Specific stimulation and suppression tests for pituitary hormones are performed in selected situations for detecting the type of hypersecretion or the response to treatment. Imaging procedures (mainly magnetic resonance imaging, MRI, nowadays) determine the presence, size and extent of the lesion. The classification of pituitary tumors is based on the staining properties of the cell cytoplasm viewed by light microscopy and immunocytochemistry revealing the secretory pattern of the adenoma. Treatment of pituitary adenomas consists of surgery (performed in more than 99% of cases via a transphenoidal route) and radiotherapy, generally fractionated or, in selected cases, using stereotactic techniques such as gamma-knife. The availability of medical treatment (dopamine, DA, agonists, somatostatin analogs, GH-receptor antagonists...) has profoundly modified the indications of radiotherapy, drugs being now generally used as a second-line treatment, after surgery (or even as first-line treatment). Based on the results of the different treatment modalities for each type of pituitary adenoma, recommendations will be proposed. They may be summarized as follows. For treatment of GH-secreting adenomas, trans-sphenoidal surgery is the first-line therapy except when the macroadenoma is giant or if surgery is contra-indicated; postoperative radiation therapy (fractionated, or by gamma-knife) is performed for partially resected tumors or when GH levels remain elevated (eventually after a trial of somatostatin analog). Somatostatin analogs, now available in slow release form, are proposed when surgery is contra-indicated, or has failed to normalize GH levels, or in waiting for the delayed effects of radiation therapy. If the probability of surgical cure is low (e.g. in patients with very large and/or invasive tumors), then somatostatin analogs may be reasonable primary therapeutic modality provided that the tumor does not threaten vision or neurological function. Pegvisomant, the new GH-receptor antagonist, is indicated in case of resistance to somatostatin analogs. Patients with PRL-secreting microadenomas may be treated either with trans-sphenoidal surgery or medically with DA agonists. In patients with macroadenomas, even in the presence of chiasmatic syndrome, DA agonists are now proposed as primary treatment. Indeed, effects on visual disturbances are often very rapid (within a few hours or days) and tumoral shrinkage is usually very significant. For patients with ACTH-secreting adenomas, primary therapy is generally trans-sphenoidal surgery by a skilled surgeon, whether or not a microadenoma is visible on MRI. Radiotherapy is reserved for patients who are subtotally resected or remain hyper-secretory after surgery. In waiting for the effects of radiotherapy, adrenal steroidogenesis inhibitors (mitotane, ketoconazole) may be indicated. If drugs are not available or not tolerated, bilateral adrenalectomy may be proposed. For patients with clinically non functioning adenomas (generally gonadotropin-secreting adenomas on immunocytochemistry), trans-sphenoidal surgery with or without postoperative radiation therapy is performed for almost all patients whether or not they have visual consequences of their tumor. Selected patients with small, incidentally discovered microadenomas may be carefully followed without immediate therapy.
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PMID:Diagnosis and treatment of pituitary adenomas. 1576 32

The vast majority (>80%) of clinically non-functioning pituitary adenomas (NFPAs) are gonadotroph-cell adenomas, as demonstrated by immunocytochemistry. However, they are rarely associated with increased levels of dimeric LH or FSH. Increased levels of uncombined subunits (free alpha-subunit mainly, LH-beta subunit more rarely) are more frequently encountered, but are generally modest. The main problems raised by NFPA are mass effects problems, responsible for optic chiasm compression or deficient hormone secretion resulting from compression of normal anterior pituitary cells. The therapeutic management of NFPA may require combination of different options. The strategy of observation only for patients with incidentally discovered pituitary adenomas may be appropriate, provided that the tumor is well-delimited, small, has no extension with risk of neurological or visual chiasm compression, and that a meticulous hormonal work-up has ruled out the possibility of a minimal hormonal hypersecretion. Transsphenoidal surgery allows improvement in visual disturbances due to chiasmal syndrome in most patients, and sometimes, in pituitary function. After surgery alone, nearly 30% (between 10 and 69%, according to the series) of patients relapse within 5 to 10 yr. Radiotherapy is proposed either as a systematic adjunct or only if a significant remnant persists. Systematic radiation therapy is supported by the low relapse rate (mean, 11%; range, 6-21%) observed when radiation therapy is systematically associated with surgery. However, irradiation is almost always followed by hypopituitarism which might be associated with a reduction in life expectancy, despite appropriate replacement therapy. Results of medical treatment are disappointing. Dopamine agonist bromocriptine decreases gonadotropin and alpha-subunit in vitro and in vivo, but, in clinical studies, was poorly effective in reducing supranormal gonadotropins and free subunits levels, and rarely produced a minimal tumoral shrinkage. Cabergoline may be more efficacious. Somatostatin analogs are able to improve minimally visual problems in 20-40% of cases, but reduction in tumoral volume is anecdotic. Whether new somatostatin analogs (e.g. SOM230 which is a multiligand agonist) will improve these results is presently unknown. Administration of GnRH agonists is generally ineffective and may be hazardous. Prolonged administration of GnRH antagonist in a small number of patients with a secreting gonadotroph cell adenoma has been reported to reduce supranormal gonadotropins levels but not to produce any change in tumoral size.
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PMID:Non-functioning pituitary adenomas. 1662 56

We report two cases of acromegaly in elderly patients. Both patients had markedly invasive GH-secreting macroadenomas, which caused hugely increased circulating GH levels (over 90 ng/ml). The first patient, 79 year-old, presented with goitre and severe osteoarthrosis, refused surgery and was treated with various somatostatin analogues (ultimately accompanied by cabergoline), without satisfactory control of the disease. The second patient, 67-year-old, presented with symptoms secondary to hypopituitarism, which had been previously misdiagnosed. These symptoms resolved with the appropriate substitutive therapy, which led to a significant improvement in her condition. However, two transphenoidal operations, radiotherapy and long-term somatostatin agonist therapy were required to control GH hypersecretion satisfactorily. The authors wish to underline that acromegaly is a rare but not negligible disorder in the elderly, which can affect the whole body functions and cause severe morbidities. In the two cases presented somatostatin agonists alone were not able to control the tumoral hypersecretion adequately. The prompt discovery (usually through a simple clinical evaluation) of this disease in the elderly, confirmed by hormonal and morphological evaluation, together with a multidisciplinary (medical, surgical, radiotherapeutic) approach can improve their quality of life and increase life expectancy.
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PMID:[Acromegaly: multifaceted clinical presentation of a rare disease of the elderly. Report of two cases with long-term follow-up]. 1672 89

To cure acromegalic patients, transsphenoidal surgery is considered first, especially for microadenoma. However, less than 50% of patients with macroadenoma achieve satisfactory biochemical control. Moreover, surgery may cause hypopituitarism. Medical therapy may offer the prospect of near normalization of growth hormone (GH)/insulin-like growth factor-1 levels with substantial tumor shrinkage in a significant number of patients. Here, we report two cases of acromegaly under treatment with somatostatin analogs alone for more than 10 years. Case 1 was a 54-year-old man with a pituitary macroadenoma. He received 4 years of octreotide treatment followed by 6 years of prolonged-release (PR) lanreotide resulting in normal GH level. Case 2 was a 60-year-old woman with a 1.3 cm pituitary tumor. She received 8 years of octreotide treatment followed by 6 years of PR lanreotide resulting in subnormal GH level and gallbladder sludge. She had received bilateral total hip replacement for hip osteoarthritis at the age of 59 years. These cases illustrate that long-term treatment with somatostatin analogs offers an alternative choice in selected acromegalic patients, such as those with pituitary tumor who cannot be cured by surgery, those who have unacceptable anesthetic risk and those who refuse surgery.
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PMID:Long-term primary medical therapy with somatostatin analogs in acromegaly. 1693 68

Non-functioning pituitary tumors are relatively common. A large number of these tumors are incidentally found pituitary microadenomas (<1 cm) and are usually of no clinical importance. Those tumors that require treatment are generally macroadenomas and come to medical attention because of mass effect and/or hypopituitarism. Visual field defects are present in roughly 70% of patients with non-functioning macroadenoma at the time of diagnosis and the majority of these patients have at least growth deficiency and hypogonadism. By immunocytochemistry, the large majority of these tumors are glycoprotein producing and less commonly they are non-functioning somatotroph, lactotroph or corticotoph adenomas. In contrast to the immunocytochemistry results, only a minority of these tumors actively secrete intact gonadotrophs or glycoprotein subunits. Therapy is directed at eliminating mass effect and correcting hypopituitarism. There are anecdotal reports of tumor shrinkage during therapy with either dopamine agonists or somatostatin agonists; however tumor response to medical treatment is not reliable. For most patients, transphenoidal resection of the tumor is the preferable primary treatment. Surgery improves visual defects in the majority of patients and a lesser number will recover pituitary function. In the past, pituitary radiation was commonly administered following pituitary surgery; however the need for routine radiation has recently been reevaluated. Although tumor recurrence at 10 years post surgery may be as high as 50%, few patients with recurrence will have clinical symptoms. Close follow-up with surveillance pituitary scans should be performed after surgery and radiation therapy reserved for patients having significant tumor recurrence.
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PMID:Clinically non-functioning pituitary adenoma. 1708 98

Growth-hormone hypersecretion, acromegaly, is associated with reduced life expectancy. First line treatment remains surgery, but remission rates vary between 50% and 90%. In case of lack of surgical remission or recurrence, somatostatin agonists can be proposed. However, about 30% of patients are partially or totally resistant to this treatment. The growth hormone receptor antagonist pegvisomant currently needs more prolonged follow-up studies. Conventional radiotherapy and radiosurgery are two radiation treatment modalities that can be proposed to these resistant patients. Reported rates of remission for conventional radiotherapy range between 50% and 60% in patients with acromegaly, with a time to remission delayed by several years, and adverse effects including high rates of hypopituitarism. This treatment could be proposed to patients with aggressive adenomas, in whom surgery cannot allow biochemical control. In contrast, studies on stereotactic radiosurgery reported lower rates of remission, with faster growth hormone hypersecretion decline, and a lower risk of adverse effects. However, this latter technique requires a well defined target volume, which limits its indications. The high precision of this technique makes it possible to be used as an alternative primary treatment to surgery. We reviewed major advantages and drawbacks of each of these techniques, based on recent studies to try to define their respective indications in the therapeutic algorithm of acromegaly.
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PMID:Radiotherapy and radiosurgery in acromegaly. 1817 23

Surgery is the first-line treatment of patients with clinically non-functioning pituitary adenomas (NFAs). Because of lack of clinical syndrome these tumours are diagnosed with a variable delay, when patients suffer from compression symptoms (hypopituitarism, headache and visual field defects) due to the extension of the tumour outside the pituitary fossa. Surgery is followed by residual tumour tissue in most patients. In these cases, radiotherapy is generally used to prevent tumour regrowth. However, NFA cell membranes, in analogy with GH- and PRL-secreting adenomas, express somatostatin and dopamine receptors. Treatment with somatostatin analogues (SSA) and dopamine agonists (DA) induced some beneficial effects on visual field defects and was also followed by tumour shrinkage in a minority of cases. DA seem to be more effective on tumour shrinkage than SSA. More recently, a combination treatment with both SSA and DA have been tested in a few patients with interesting results. Lack of randomized, placebo-controlled trials prevents any conclusion on the efficacy of these drugs. By contrast, use of gonatotrophin-releasing hormone analogues has been abandoned.
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PMID:Medical therapy for clinically non-functioning pituitary adenomas. 1878 Jul 96

Clinically non-functioning pituitary adenomas and gonadotroph-cell adenomas are relatively common: microadenomas (< 1cm) are usually pituitary incidentalomas while most macroadenomas are revealed by mass effect and/or hypopituitarism. They are rarely associated with high gonadotropin (Luteinizing hormone, LH; Follicle-stimulating hormone FSH) levels while increased alpha-subunit levels are more frequent. Immunocytochemistry of pituitary tumor confirms the diagnosis of clinically non-functioning or gonadotroph-cell adenoma. Pituitary MRI follow-up seems to be indicated for microadenoma. Treatment of macroadenoma with visual field defect or hypopituitarism is transphenoidal surgery, but cure is rarely obtained and tumor recurrence is significant during follow-up. Therefore postoperative treatment (pituitary radiotherapy or medical treatment with dopamine agonists or somatostatin analogs) should be discussed against close follow-up with repeated MRI scans.
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PMID:[Clinically non functioning pituitary adenomas and gonadotroph-cell adenomas]. 1899 May 42


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