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)

Two cases of diabetes mellitus in juvenile dogs (a 3-4 month-old Golden Retriever and a 2-month-old Labrador Retriever) are described here in terms of their clinical, histologic, and immunohistologic findings. Only very few insulin-positive cells were demonstrated immunohistochemically in one dog. In the second dog, the alterations of the pancreas consisted of hydropic vacuolar degeneration of B cells in the islets of Langerhans. In both cases, hyperplasia of the vacuolated cells was prominent. These cells formed tubular structures and were immunohistochemically positive for cytokeratin and proliferating cell antigen (MIB-1). Furthermore, within these vacuolated areas, some cells were positive to varying degrees for insulin, glucagon, somatostatin, and pancreatic polypeptide. Apoptotic cells could be seen in the exocrine pancreas, in vacuolated areas, and occasionally in the islets of both dogs. We interpret these alterations as ductuloendocrine cell proliferation, probably as an idiopathic compensatory response.
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PMID:Ductuloendocrine cell proliferation in the pancreas of two young dogs with diabetes mellitus. 906 86

Tumor growth depends on several factors, including angiogenesis. Tumors cannot grow if new vessels are not formed to supply the cells with oxygen and other nutrients and to remove waste products. Increased angiogenesis can be correlated with tumor growth and metastatic potential in many tumor types, indicating that neoformation of vessels is a prognostic indicator of tumor behavior. We evaluated microvessel densities in 157 various pituitary adenoma types and seven pituitary carcinomas using immunocytochemistry for CD-34 antigen, a reliable marker of endothelial cells. The lowest percentage of microvessel density was found in growth hormone-producing adenomas, the highest level in pituitary carcinomas. In general, no major correlation was found between MIB-1 index (an indicator of cell proliferation) and microvessel density. The statistical study also demonstrated no gender-dependent changes in the microvessel density of pituitary tumors. Although the microvessel density was not significantly different in relation to invasiveness of pituitary tumors, our results demonstrate a tendency of invasive pituitary tumors to be more highly vascularized than non-invasive ones. Dopamine agonist and long-acting somatostatin analog treatment compared with untreated tumors did not significantly affect microvessel densities. Statistical differences were demonstrated in the microvessel density of macroadenomas between patients older and patients younger than 40 years. Significant differences were also apparent in the microvessel densities between microadenomas and macroadenomas diagnosed in young patients but not in the older age group. The strongly positive correlation observed between microvessel density and age is consistent with the view that age of the host may have an influence on the extent of neovascularization of pituitary adenomas.
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PMID:Microvessel density in pituitary adenomas and carcinomas. 1146 92

We report a unique case of gallbladder adenocarcinoma associated with florid neuroendocrine cell nests and extensive Paneth cell metaplasia that has not been described previously. The patient was a 79-yr-old woman with a pedunculated, polypoid mass in the gallbladder. Microscopically, the mass was composed at tumor cells showing tubular and papillary growth patterns, consistent with well-differentiated adenocarcinoma. One-third or more of the tumor cell showed Paneth cell appearance. Goblet cell-type tumors were also intermingled. In addition, neuroendocrine cell nests, that were connected to the neoplastic glands, were scattered throughout the stroma. lmmunohistochemically, the labeling index of MIB-1 in adenocarcinoma cells including Paneth cell-type carcinoma cells was approx 40%. Neuron-specific enolase, chromogranin A, and synaptophysin were positive in the neuroendocrine cells forming solid nests and intermingled within neoplastic glands. They were immunopositive for serotonin but negative for insulin, glucagon, somatostatin, and pancreatic polypeptide (PP). Although MIB-1-positive neuroendocrine cell nests were very few with weak staining, we think that the neuroendocrine cell nests were neoplastic in nature. The formation of the multifocal neuroendocrine nests may be a consequence of the trophic effects of unknown substance(s), which can promote serotonin producing neuroendocrine cells to proliferate. We postulate that Paneth cell-type carcinoma cells may be intimately related to such substance(s) in our case.
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PMID:Gallbladder Adenocarcinoma with Florid Neuroendocrine Cell Nests and Extensive Paneth Cell Metaplasia. 1211 61

DNA topoisomerase IIalpha (Topo IIalpha) is a molecular and immunohistochemical marker that indicates proliferation rate and is the target for several antineoplastic agents. The present immunohistochemical study of a large series of surgically removed pituitary tumors was designed to assess the prognostic significance of Topo IIalpha expression relative to patient age, gender, tumor type and size, invasiveness, metastasis, MIB-1-labeling index and angiogenesis. Changes of Topo IIalpha expression in the tumors treated with bromocriptine and octreotide, a long-acting somatostatin analogue were also investigated. Topo IIalpha immunopositivity was detected only in the nuclei of tumor cells. Gonadotroph adenomas, null cell adenomas, and ACTH-producing adenomas had the lowest Topo IIalpha indices, whereas primary pituitary carcinomas and silent type 3 adenomas presented the highest counts. The statistical study demonstrated no significant correlation between Topo IIalpha expression, patient gender, and vascularity. In contrast, significant negative correlation was found between Topo IIalpha expression and patient age. Topo IIalpha expression was significantly higher in invasive than noninvasive tumors. A tendency to have higher counts was also observed in microadenomas compared with in macroadenomas. Although Topo IIalpha and MIB-1 indices were similar in most tumor types, no significant correlation between Topo IIalpha and MIB-1-labeling indices (r =.16, P =.09) was found. Only non-functioning adenomas showed positive correlation (r =.41, P =.006) between both proliferation markers. Our results demonstrated a significant decrease in Topo IIalpha index in octreotide-treated, GH-producing adenomas, compared with untreated tumors, but no significant changes were observed in bromocriptine-treated, PRL-producing adenomas. The present study showed no significant advantage of Topo IIalpha over MIB-1 as a prognostic marker; however, Topo IIalpha may provide crucial information regarding selection of adenohypophyseal tumors responsive to antineoplastic therapy, such as invasive pituitary adenomas and pituitary carcinomas, which exhibit a high Topo IIalpha index.
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PMID:Topoisomerase IIalpha expression in pituitary adenomas and carcinomas: relationship to tumor behavior. 1242

We have previously reported that sst2A somatostatin receptors are frequently overexpressed in human meningiomas. Initial clinical observations suggest that somatostatin analogues may also be of value for imaging and treatment of other human intracranial tumors, including astrocytomas. However, contradictory results have been reported regarding the expression of somatostatin receptors in low-grade and high-grade astrocytomas. Therefore, we determined the precise pattern of somatostatin receptor protein expression in 8 diffuse astrocytoma (DA), 10 anaplastic astrocytomas (AA), and 32 glioblastoma multiforme (GBM) using immunohistochemistry and Western blot analysis. sst1 and sst2A somatostatin receptors were not present in DA and only occasionally detected in AA. In GBM, sst1 was present in 66%, and sst2A was found in 44% of the tumors. sst3 receptors were present in 38% of DA, 40% of AA, and 84% of GBM. Thus, loss of differentiation was significantly associated with increased expression of sst1, sst2A, and sst3 somatostatin receptors. In contrast, sst4 and sst5 receptors were found in 80% and 25% of all cases, respectively, in a manner independent of histological grade. No significant correlation was found between somatostatin receptor expression and the proliferation rate of the tumors as determined by MIB-I immunostaining. Furthermore, the presence or absence of the 5 somatostatin receptor subtypes did not significantly influence survival time in 14 GBM patients.
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PMID:Differential expression of sst1, sst2A, and sst3 somatostatin receptor proteins in low-grade and high-grade astrocytomas. 1474 57

Somatostatin receptors (SSTRs) have been detected in many normal and malignant tissues. This wide expression has been used for diagnostic, prognostic and therapeutic purposes. Five SSTR subtypes (SSTR 1-5) have been identified whose activation is responsible for the signal transduction through many different intracellular pathways. In the present study the expression of SSTR mRNA was determined by reverse-transcriptase (RT)-PCR in 42 meningiomas. About 88% of the tumors analyzed (37/42) were positive for at least one of the five SSTR subtypes displaying a variable pattern of expression of the different SSTR subtypes. SSTRI and SSTR2 were the most frequently mRNA detected (69% and 79% of the sample analyzed, respectively). The other subtypes were found in the 43%, 33% and 33% of cases for SSTR3, SSTR4 and SSTR5, respectively. In 22, out of 42 patients (52%) three or more SSTRs were detected. The expression of the different SSTR subtypes did not correlate with the expression of bcl-2 (apoptosis-associated protein) and MIB-1 (a proliferation marker), assessed by immunohistochemistry in a series of 34 tumor samples, while a correlation between the expression of SSTR3 and p53 was observed (p = 0.08). To evaluate a possible role of SSTR in the control of human meningioma cell proliferation, seven primary cell cultures obtained from fresh meningioma surgical tissues, were analyzed for their proliferative behavior by MTT assay and for their response to SST by [3H]-thymidine incorporation. In four out of six tumors (in one case no SSTR were detected) the treatment with SST caused a significant inhibition of DNA synthesis induced by the tumor-promoter phorbol myristate acetate. The evidence of the expression of SSTRs, mainly of SSTR2, in this series of specimens we analyzed altogether with in vitro antiproliferative effects of SST may open interesting perspectives for the diagnosis and the therapy of meningiomas.
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PMID:Expression of somatostatin receptor mRNA in human meningiomas and their implication in in vitro antiproliferative activity. 1501 81

We describe a hitherto undocumented variant of dimorphic pituitary neoplasm composed of an admixture of neurosecretory cells and profuse leiomyomatous stroma around intratumoral vessels. Radiologically perceived as a macroadenoma of 3.8 cm in diameter, this pituitary mass developed in an otherwise healthy 43-year-old female. At the term of a yearlong history of amenorrhea and progressive bitemporal visual loss, subtotal resection was performed via transsphenoidal microsurgery. Discounting mild hyperprolactinemia, there was no evidence of excess hormone production. Histologically, solid sheets, nests and cords of epithelial-looking, yet cytokeratin-negative cells were seen growing in a richly vascularized stroma of spindle cells. While strong immunoreactivity for NCAM, Synaptophysin and Chromogranin-A was detected in the former, the latter showed both morphological and immunophenotypic hallmarks of smooth muscle, being positive for vimentin, muscle actin and smooth muscle actin. Architectural patterns varied from monomorphous stroma-dominant zones through biphasic neuroendocrine-leiomyomatous areas, to pseudopapillary fronds along vascular cores. Only endothelia were labeled with CD34. Staining for S100 protein and GFAP, characteristics of sustentacular cells, as well as bcl-2 and c-kit was absent. Except for alpha-subunit, anterior pituitary hormones tested negative in tumor cells, as did a panel of peripheral endocrine markers, including serotonin, somatostatin, calcitonin, parathormone and vasoactive intestinal polypeptide. Mitotic activity was absent and the MIB-1 labeling index low (1-2%). While assignment of this lesion to any established neoplastic entity is not forthcoming, we propose it is being considered as a low-grade neuroendocrine tumor possibly related to null cell adenoma.
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PMID:Leiomyomatoid angiomatous neuroendocrine tumor (LANT) of the pituitary: a distinctive biphasic neoplasm with primitive secretory phenotype and smooth muscle-rich stroma. 1652 Sep 66

Spindle cell metaplasia in thyroid adenoma or carcinoma is rare and its pathological features are not well characterized. Distinction of this entity from medullary or anaplastic carcinoma has an important clinical implication. We encountered a case of thyroid follicular adenoma associated with spindle cell metaplasia. It showed "tumor in tumor appearance" and neoplastic spindle cells were positive for thyroglobulin, thyroid transcription factor-1, vimentin and focally chromogranin A and somatostatin (SS). MIB-1 index was <1%. Ultrastructure of the spindle cells was reminiscent of follicular cell origin. From the findings from our case, spindle cell metaplasia appears to be a benign clinical entity, suggestive of multidirectional differentiation of follicular cells.
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PMID:Spindle cell metaplasia arising in thyroid adenoma: characterization of its pathology and differential diagnosis. 1661 Feb 45

Composite adenoma-carcinoid tumors are rare colorectal lesions consisting of intermingled adenomatous and carcinoid components. Unlike other mixed endocrine-glandular colorectal neoplasms, which are generally malignant, their glandular component is histologically benign and their natural history is favorable. We present 4 cases of colonic adenomas containing microcarcinoids, a hitherto undescribed lesion that is either a precursor of composite adenoma-carcinoids or a related but independent entity. The cases, identified among our surgical and consultation files, were endoscopically routine sessile polyps removed from 4 otherwise normal individuals, 3 from the cecum and 1 from the distal colon. The microcarcinoids were 0.5 to 1.5 mm in size and situated within the basal lamina propria, where they interposed between the crypts and muscularis mucosae without disturbing the overall polyp architecture. Histologically, they consisted of collections of low-grade epithelial cells arranged in nests, cords, tubules, and irregular clusters and characterized by eosinophilic, granular, or clear cytoplasm and by round central nuclei with stippled or dusty chromatin. Endocrine differentiation of the microcarcinoids was confirmed by the expression of 3 or more of the following: Grimelius argyrophil, chromogranin, synaptophysin, neuron-specific enolase and somatostatin. No mitotic figures or MIB-1 or p53 positivity were observed. The glandular component of the polyps was unremarkable in 3 cases, but 1 polyp, in addition to a microcarcinoid, showed a diffuse pattern of mixed adenomatous-endocrine differentiation. The patients' clinical course was benign on the basis of 2 years' median follow-up (range, 6 mo to 10 y). Two patients with incomplete polypectomies underwent hemicolectomy revealing no residual endocrine neoplasia. Awareness of microcarcinoids in colonic adenomas should help avert potential diagnostic pitfalls posed by their pleomorphism, basal location, and infiltrative patterns, and may help clarify their natural history and possible relationship to composite glandular-carcinoid tumors.
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PMID:Microcarcinoids in large intestinal adenomas. 1712 8

The patient with a history of bone pain and muscle weakness, was thought to have oncogenic osteomalacia as a result of biochemical investigations and directed to Nuclear Medicine Department for a whole-body bone scintigraphy and 111In-octreotide scintigraphy. There was no focal pathologic tracer uptake, but generalized marked increase in skeletal uptake on bone scintigraphy. Octreotide scintigraphy showed accumulation of octreotide in the region of the left lobe of the thyroid gland in the neck. Thereafter, parathyroid scintigraphy was performed with technetium-99m labeled metroxy-isobutyl-isonitryl (99mTc-MIB) and MIBI scan demonstrated radiotracer uptake at the same location with octreotide scintigraphy. The patient underwent left inferior parathyroidectomy and histopathology confirmed a parathyroid adenoma. Somatostatin receptor positive parathyroid adenoma may show octreotide uptake. Octreotide scintigraphy may be promising and indicate a possibility of using somatostatin analogues for the medical treatment of somatostatin receptor positive Conflict of interest:None declared.
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PMID:Octreotide uptake in parathyroid adenoma. 2348 97


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