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

Calcitonin- and serotonin-storing cells have been immunocharacterized in prostate gland, urethra, urinary bladder and anal canal. In addition, a few hCG and somatostatin immunoreactive cells have been detected in prostate gland. All these cells were dispersed throughout the epithelial lining. In the anal canal, calcitonin cells were exclusively confined to the anal ducts and anal transitional zone epithelium. Calcitonin and serotonin cells were seen in some examples of prostatic adenocarcinoma. Combined techniques most often showed coexistence of calcitonin and serotonin immunoreactivities in the same endocrine cell. hCG immunoreactive cells corresponded to a subpopulation of serotonin-, calcitonin-storing cells. Calcitonin and serotonin cells were present in most organs which originated from the cloaca. In this territory, this distinctive endocrine pattern could be regarded as an excellent marker of cloacal derived tissues. These tissues constitute an additional site for extrathyroid C-cells. It is likely that calcitonin cells are a component of some prostatic adenocarcinomas.
 ...
PMID:Calcitonin immunoreactive cells in prostate gland and cloacal derived tissues. 287 50

Thirty-one patients with metastatic hormone-refractory prostatic adenocarcinoma were investigated scintigraphically with the 111In-labeled somatostatin analogue [DTPA-D-Phe1]-octreotide (OctreoScan) and with 99mTc-labeled HDP. In vitro somatostatin receptor autoradiography was performed on biopsies obtained from eight patients with hormone-refractory prostatic adenocarcinoma. In 30 of 31 patients (94%), at least one metastasis was positive at OctreoScan scintigraphy. Of the 346 lesions detected with 99mTc-labeled HDP bone scintigraphy, 128 were visualized with the OctreoScan technique, thus accounting for a 37% detection rate. Two uptakes on OctreoScan could not be identified on bone scintigraphy and were, thus, assessed as false positive. The biopsies of the eight patients disclosed a low density of receptors, localized on the tumor cells, as demonstrated with receptor autoradiography. Two patients with untreated metastatic prostatic adenocarcinoma were investigated in vivo before the start of endocrine therapy. However, none of the lesions detected by bone scintigraphy in these patients could be visualized with the OctreoScan technique. Positron emission tomography using [11C] methionine showed a decreased uptake in a metastatic index lesion in a patient treated with octreotide. It is concluded that hormone-refractory prostatic adenocarcinoma expresses somatostain receptors both in vitro and in vivo. The results obtained form the basis for the development of a new tool for in vivo characterization and of a new treatment strategy in patients with hormone-refractory prostatic adenocarcinoma.
 ...
PMID:Metastatic hormone-refractory prostatic adenocarcinoma expresses somatostatin receptors and is visualized in vivo by [111In]-labeled DTPA-D-[Phe1]-octreotide scintigraphy. 749 50

The effects of somatostatin analogue RC-160 and bombesin/gastrin releasing-peptide (GRP) antagonist RC-3095 were evaluated in Copenhagen rats bearing the anaplastic, androgen-independent Dunning R3327-AT-1 prostatic adenocarcinoma. In the first experiment, RC-160 was given in the form of microcapsules releasing 60 micrograms/day/rat. RC-3095 was administered from implanted Alzet osmotic minipumps liberating 100 micrograms/day/rat. After 32 days, tumor volumes and weights were significantly reduced by RC-160 as compared with the control group. Tumor doubling time in rats treated with RC-160 was significantly longer than in controls. Bombesin/GRP antagonist RC-3095 also significantly reduced tumor volume after 7 days of treatment, but after 18 days the inhibition in tumor volume was no longer significant. Tumor growth was not suppressed by castration. In the second experiment, 3-mm3 fragments of Dunning R-3327-AT-1 tumor were implanted orthotopically into the prostates of Copenhagen rats in order to evaluate the survival time of animals bearing this cancer during treatment with RC-160 released from Alzet osmotic minipumps at a dose of 100 micrograms/day/rat. Treatment with RC-160 significantly (P < 0.05) prolonged the mean survival time of rats by 5.3 days as compared to control animals. In both experiments, therapy with RC-160 significantly decreased serum growth hormone or insulin-like growth factor I levels. In the first experiment, receptor assays on R-3327-AT-1 tumor membranes showed high affinity binding sites for somatostatin, bombesin, and epidermal growth factor. At the end of the treatment, receptors for epidermal growth factor were significantly down-regulated by treatment with RC-160 but not with RC-3095. The binding capacity of bombesin receptors was reduced to nondetectable levels after the treatment with RC-3095. In cell cultures, high affinity binding sites for bombesin/GRP were found on intact Dunning R-3327-AT-1 cells, but receptors for somatostatin could not be detected. Proliferation of the AT-1 cell line was significantly inhibited by antagonist RC-3095. However, no effect on tumor cell growth in vitro was observed with analogue RC-160. Our results demonstrate that somatostatin analogue RC-160 and bombesin/GRP antagonist RC-3095 can inhibit the growth of the androgen-independent Dunning R-3327-AT-1 prostatic cancer in rats, although the remission produced by RC-3095 may be of short duration due to a down-regulation of bombesin receptors. Our work suggests the merit of further investigation as to whether these analogues can induce a possible delay in relapse and prolong survival in prostate cancer.
 ...
PMID:Inhibitory effects of somatostatin analogue RC-160 and bombesin/gastrin-releasing peptide antagonist RC-3095 on the growth of the androgen-independent Dunning R-3327-AT-1 rat prostate cancer. 790 3

Neuroendocrine cells are thought to have a regulatory role in prostatic epithelial growth and may be prognostically useful in prostatic adenocarcinoma. To determine the extent of neuroendocrine differentiation in high-grade prostatic intraepithelial neoplasia (PIN), a putative precursor of cancer, we studied the immunohistochemical expression of 10 markers in 26 radical prostatectomy specimens with PIN and adenocarcinoma. Expression was measured as mean percent of positive cases and positive high-power (x40) fields. The highest percentage of cases showed immunoreactivity for serotonin (73%, PIN; 54%, carcinoma), neuron-specific enolase (NSE) (67%, PIN; 46%, carcinoma), chromogranin (62%, PIN; 65%, carcinoma), and human chorionic gonadotropin (hCG) (30%, PIN; 22%, carcinoma); the remaining markers showed immunoreactivity in fewer than 5% of cases (somatostatin, calcitonin, corticotropin) or in no cases (thyrotropin, prolactin, and glucagon). At least one of the markers was present in 88% of cases of PIN and 92% of carcinoma. Non-neoplastic epithelial cells expressed serotonin, NSE, chromogranin, and hCG in every case, and the expression was significantly greater than in PIN and cancer. Stepwise regression analysis revealed the following positive correlations: chromogranin expression in PIN and patient age, NSE expression in cancer and number of lymph node metastases, and hCG expression in cancer and percentage of Gleason pattern 5; serotonin expression in PIN and cancer did not correlate with any of the clinical and pathologic factors. Neuroendocrine differentiation is downregulated in prostatic carcinogenesis, with intermediate levels of expression in PIN compared with normal cells and carcinoma.
 ...
PMID:Neuroendocrine differentiation in prostatic intraepithelial neoplasia and adenocarcinoma. 797 47

Neuroendocrine (NE) differentiation of prostatic adenocarcinomas has received increasing attention in recent years as a result of possible implications on prognosis and therapy. The incidence of NE cells in tumors has been reported from 10% up to 100%. Several studies have shown chromogranin A (CgA) to be the most reliable serum marker of NE differentiation. We have followed 22 patients with prostatic adenocarcinoma over a 2-year period. The patients underwent a palliative transurethral resection of the prostate (TURP) because of urinary outflow obstruction. The prostatic tissue specimens were stained immunohistochemically using antibodies against CgA, chromogranin B (CgB), neuron-specific enolase (NSE), thyroid-stimulating hormone (TSH), serotonin, and somatostatin. In addition, each specimen was stained with hematoxylin & eosin (H & E), and saffran for tumor grading. Blood samples were taken preoperatively and after 1, 3, 6, and 24 months. The serum values of CgA, CgB, pancreastatin (Pst), NSE, and prostate-specific antigen (PSA) were determined from each sample. Carcinomas with groups of CgA-positive cells had higher serum levels of CgA compared to carcinomas with no or only scattered CgA-positive NE cells. During the 2-year period, there were no statistical significant variations in serum levels of CgA, NSE, Pst, and PSA. However, there was a significant increase in serum levels of CgB during the same period, P = 0.002, possibly due to an increase in number of NE cells in tumor or to a relative increase in production of CgB in the NE cells.
 ...
PMID:Use of neuroendocrine serum markers in the follow-up of patients with cancer of the prostate. 914 Jan 24

A pilot study to evaluate the predictive value of Indium-111-labelled somatostatin analogue [DTPA-D-Phe1]-octreotide scintigraphy (OctreoScan111) in the Octreotide treatment of hormone-refractory prostatic adenocarcinoma was initiated. Ten patients were investigated with OctreoScan111 with regard to disease extension and tumor-to-background ratio. Subsequently, the patients were treated with Octreotide (Sandoz, Basel, Schweiz) at a dose of 100 micrograms twice a day subcutaneously. Three patients experienced symptomatic relief, and two of these responded with a decrease in PSA. Three patients did not notice any difference after 6 months of treatment and two of them developed an increase in their PSA value. One patient progressed after five months as regards both PSA and symptoms. Three patients were not able to complete treatment. Of the seven evaluable patients, the three with the highest tumour-to-background ratios at OctreoScan111 were those patients with reduced or stable PSA levels, and none of these progressed during treatment. Previous reports along with this study demonstrate that only a minority of patients with hormone-refractory prostatic adenocarcinoma benefit from Octreotide treatment. However, OctreoScan111 investigations may identify patients who will respond to Octreotide therapy.
 ...
PMID:[111In-DTPA-D-Phe1]-octreotide scintigraphy in patients with hormone-refractory prostatic adenocarcinoma can predict therapy outcome with octreotide treatment: a pilot study. 956 70

A 74-yr-old man with prostatic adenocarcinoma underwent magnetic resonance 1H-spectroscopic imaging (1H-MRSI) of the prostate. Based on the results, he was treated with combination therapy using complete androgen blockade (leuprorelin acetate 3.75 mg every 4 wk plus bicalutamide 50 mg daily) and a somatostatin analogue (lanreotide acetate 60 mg every 4 wk). Serum prostate-specific antigen and chromogranin A levels steadily decreased over a 12-mo follow-up period, at which time the patient is alive without disease progression and with a complete objective and symptomatic response.
 ...
PMID:Complete response to the combination therapy with androgen blockade and somatostatin analogue in a patient with advanced prostate cancer: magnetic resonance imaging with 1H-spectroscopy. 1731 66

Small cell carcinoma (SCC) of the prostate is an uncommon condition; there are very few cases in which presenting symptoms are consistent with Cushing Syndrome (CS). We report a new case in which CS triggers the suspicion of an SCC of the prostate and a review of the published cases of SCC of the prostate presenting with CS. The origin of these neoplasms is still unclear. It may be suspected when laboratory features appear in patients diagnosed with prostatic adenocarcinoma which becomes resistant to specific therapy. SCC usually occurs after the 6th decade. Patients suffering SCC of the prostate presenting with CS usually present symptoms such as hypertension, hyperglycemia, alkalosis or hypokalemia; cushingoid phenotype is less frequent. Cortisol and ACTH levels are often high. Prostatic-specific antigen levels are usually normal. CT scan is the preferred imaging test to localize the lesion, but its performance may be improved by adding other tests, such as FDG-PET scan. All patients have metastatic disease at the time of diagnosis. Lymph nodes, liver and bone are the most frequent metastases sites. Surgery and Ketokonazole are the preferred treatments for CS. The prognosis is very poor: 2- and 5-year survival rates are 27.5 and 14.3%, respectively. Key messages When a patient presents with ectopic Cushing Syndrome but lungs are normal, an atypical localization should be suspected. We should suspect a prostatic origin if Cushing Syndrome is accompanied by obstructive inferior urinary tract symptoms or in the setting of a prostatic adenocarcinoma with rapid clinical and radiological progression with relatively low PSA levels. Although no imaging test is preferred to localize these tumors, FDG-PET-TC can be very useful. Hormone marker scintigraphy (e.g. somatostatin) could be used too. As Cushing Syndrome is a paraneoplastic phenomenon, treatment of the underlying disease may help control hypercortisolism manifestations. These tumors are usually metastatic by the time of diagnosis. They have very poor prognosis.
...
PMID:Small cell carcinoma of the prostate presenting with Cushing Syndrome. A narrative review of an uncommon condition. 2706 90

We presented a promising result of radionuclide therapy using Lu-PSMA and Lu-DOTATATE in a patient with prostatic adenocarcinoma and neuroendocrine differentiation. Functional imaging of somatostatin receptors in patients with metastatic castration-resistant prostate cancer may pave the way toward implementation of novel radionuclide targets for the treatment of this aggressive subtype of prostate cancer.
 ...
PMID:177Lu-PSMA and 177Lu-DOTATATE Therapy in a Patient With Metastatic Castration-Resistant Prostate Cancer and Neuroendocrine Differentiation. 3168 80