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)

Merkel cell carcinoma (cutaneous neuroendocrine carcinoma) is a highly malignant, neuroendocrine skin tumor. It mostly occurs in elderly patients in the sun-exposed skin of the head and neck and the extremities. Merkel cell carcinomas develop as fast-growing dermal tumors. They are characterized by a high frequency of lymph-node metastases (50%) and local recurrences (25-77%). The 5-year survival rate is 30-74%. Histology reveals uniform, round cells with a small cytoplasmic rim expressing cytokeratin 20, neurofilament, synaptophysin, chromogranin, and neuron-specific enolase. Ultrastructurally, 100-200 nm electron dense granules are typical findings. Wide surgical excision, followed by radiotherapy, is the treatment of choice. Regional lymph-node metastases should be treated by radical lymph-node excision and radiotherapy. In advanced metastatic Merkel cell carcinoma, a remission can be achieved by different chemotherapy schedules or the somatostatin analogue octreotide. However, the prognosis remains poor. The current knowledge about this disease and guidelines for effective diagnosis and treatment are given.
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PMID:[Merkel cell carcinoma: a diagnostic and therapeutic challenge]. 1135 30

Cocaine- and amphetamine-regulated transcript (CART) is an anorexigenic peptide widely expressed in the central and peripheral, including the enteric, nervous systems. CART is also expressed in pituitary endocrine cells, adrenomedullary cells, islet somatostatin cells, and in rat antral gastrin cells. We used immunocytochemistry (IHC) and in situ hybridization (ISH) to study CART expression in developing rat pancreas. We also examined co-expression of CART and islet hormones and developmental markers and the effect of CART on proliferation using clonal insulin cells (INS-1 832/13). A major portion of each of the islet cell types, except the ghrelin cells, expressed CART during a period before and around birth. Two weeks postnatally, CART expression was restricted to somatostatin cells. Pre- and early postnatally, many of the CART-expressing cells co-expressed cytokeratin 20 (CK20), a marker of duct cells and islet precursor cells, the trophic hormone gastrin, and a smaller subpopulation also harbored the proliferation marker Ki67. CART was also expressed in pancreatic nerve fibers, both sensory and autonomic, and in ganglion nerve cell bodies. Although highly expressed in the developing islets, CART did not affect proliferation of INS-1 cells. We have demonstrated that CART is expressed in several islet cell types during rat development but is restricted to somatostatin cells and neurons in the adult rat.
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PMID:Cocaine- and amphetamine-regulated transcript (CART) is expressed in several islet cell types during rat development. 1472 68

Small cell carcinomas of the uterine cervix are rare tumors with an aggressive behavior. Although these tumors can exhibit neuroendocrine differentiation, the criteria for neuroendocrine differentiation are subjective and not well defined. In this study, the authors tentatively defined small cell neuroendocrine carcinoma (SCNEC) as a tumor composed of small cells with at least two of the following: argyrophilic cytoplasm, chromogranin A immunoreactivity, and synaptophysin immunoreactivity. We found 10 cases fulfilling these requirements. Five of the 10 tumors were composed mainly of small ("oat") cells and 5 of mainly larger "intermediate" cells. The majority of both subtypes showed an insular pattern. Three of the 10 SCNECs were pure, whereas the other seven were mixed with adenocarcinoma and/or squamous cell carcinoma or cervical intraepithelial neoplasia. In addition to the definitional markers noted earlier, the tumors were immunoreactive for serotonin (6 cases), somatostatin, gastrin, glucagon, and pancreatic polypeptide. No tumors were immunoreactive for cytokeratin 20. Human papillomavirus (HPV)-18 was detected in all of the pure tumors and both the SCNEC and adenocarcinomatous components in four of the mixed tumors. No other types of HPV were detected. The tumors showed a relatively low frequency of loss of heterozygosity for representative tumor suppressor gene sites; p53 mutations were found in only one case.
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PMID:Small cell neuroendocrine carcinomas of the uterine cervix: a histological, immunohistochemical, and molecular genetic study. 1538 6

We report a case of a 56-year-old male with a primary large cell neuroendocrine renal carcinoma. Grossly, the left kidney was enlarged by a solid tumor that measured 145 x 125 x 100 mm. Histologically, the tumor consisted of large cells with a moderate to abundant amount of eosinophilic cytoplasm. The nuclei were irregular, some of them with finely or coarsely granular chromatin, others with vesicular chromatin and prominent nucleoli. The tumor cells showed multiple mitotic figures (up to 32 mitoses/10 HPF). In some areas, the tumor cells were arranged in solid sheets; however, the predominant pattern was solid-alveolar, trabecular and cribriform. Large areas of tumor necrosis were found. Immunohistochemically, the tumor cells were positive for synaptophysin, CD56 and CD57. Cytokeratin AE1/AE3, vimentin and CD10 were positive only focally. Chromogranin showed weak cytoplasmic positivity in rare tumor cells. Cytokeratin CAM5.2, cytokeratin 34betaE12, BerEP 4, EMA, TTF-1, cytokeratin 7, cytokeratin 20, calretinin, serotonin, somatostatin, gastrin, calcitonin, glukagon and insulin were negative. Primary large cell neuroendocrine carcinoma of the kidney is a rare tumor. To the best of our knowledge, only 3 cases of a tumor of this type have been reported to date.
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PMID:Primary large cell neuroendocrine carcinoma of the kidney. 1957 58

Large-cell neuroendocrine carcinoma is a high-grade neuroendocrine carcinoma, originally described in the lung. The tumor rarely occurs in extrapulmonary sites like the gastrointestinal tract, and only few examples have been described in the ampulla of Vater. A new case of large-cell neuroendocrine carcinoma of the ampulla of Vater in a 60-year-old man is reported. After pancreatoduodenectomy, macroscopic examination revealed ulcerated tumor in the region of the ampulla of Vater. Microscopically, the tumor exhibited organoid, predominantly nested growth pattern, consisting of large, polygonal cells with pleomorphic nuclei. Average number of mitoses was 36 per 10 high-power fields. Small and large areas of necrosis were identified. Immunohistochemically, the tumor cells were positive for synaptophysin, chromogranin A, PGP 9.5, neuron-specific enolase, pancytokeratin, CK8 and somatostatin and negative for CK7, CK20, S-100, TTF-1, HMB-45, CD117, E-cadherin and regulatory peptides. Ki-67 proliferative index was 41%. Histone deacetylase (HDAC) analysis showed almost identical results for HDAC1, HDAC2 and HDAC3--60, 60.3 and 61%, respectively. Two months after surgery, liver metastases occurred, confirming highly aggressive behavior of large-cell neuroendocrine carcinoma.
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PMID:Large-cell neuroendocrine carcinoma of the ampulla of Vater. 1989 74

Merkel cell carcinoma (MCC) is a rare and aggressive type of neuroendocrine cancer of the skin. It predominantly affects the elderly, with a predilection for the sun-exposed skin of the head and neck. Risk factors include immune-suppressing diseases, such as human immunodeficiency virus (HIV), chronic lymphocytic leukemia and multiple myeloma, organ transplantation, and the presence of the newly-identified Merkel cell polyomavirus (MCPyV). Diagnosis is based on pathological findings, primarily the immunohistochemical determination of cytokeratin 20 positivity. By contrast, staging relies on conventional imaging methods, such as ultrasonography, computed tomography (CT) and magnetic resonance imaging, and nuclear medicine techniques, such as sentinel lymph node scintigraphy, somatostatin receptor scintigraphy (SRS), and positron emission tomography (PET)/CT with 18F-fluorodeoxyglucose (FDG) or alternative radiopharmaceuticals. The treatment of MCC is primarily surgical, with possible adjuvant radiation, while the use of chemotherapy appears to be an alternative therapeutic option that is used only in specific cases. The present study describes the case of a 43-year-old HIV-positive Caucasian man with MCC located on the posterior surface of the left thigh, which was identified by cytological and histological examination of tissue sampled by fine needle aspiration and biopsy performed under CT. SRS demonstrated a high uptake of 111In-diethylene triamine pentaacetic acid-octreotide at the affected site. Therefore, the lesion was surgically excised, and the patient received chemotherapy and adjuvant radiotherapy. Three months subsequent to treatment, the patient underwent a PET/CT scan with 18F-FDG that demonstrated uptake in the cervical lymph nodes and the area of the excised lesion. These findings indicated that the disease was in remission. The aim of the present study was to highlight the value and contribution of nuclear medicine in the diagnosis, staging and follow-up, using PET/CT, octreoscan and sentinel lymph node scintigraphy, of patients with MCC, as well as the therapeutic strategy of radiolabelled somatostatin analogue scintigraphy.
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PMID:Nuclear medicine techniques in Merkel cell carcinoma: A case report and review of the literature. 2662 19

A 58-year-old woman presented to our hospital with a huge hepatic mass. A CT scan showed an enhanced mass lesion on the fundus of the gallbladder and an enhanced mass ring on the gallbladder bed. Since FDG-PET showed no evidence of metastasis, we performed cholecystectomy, hepatectomy of S4a/5, and regional lymph node dissection. The immunohistochemical study of the specimen was positive for CK7, CK20, chromogranin A, and synaptophysin. The Ki-67 labeling index was 50%, and the SSTR2 score was 2+. The patient was diagnosed with neuroendocrine carcinoma. Since she was in poor condition and on hemodialysis, we started administration of somatostatin analog at the time of recurrence, and soon her diarrhea improved but the tumor increased in size.
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PMID:[A Case of Neuroendocrine Carcinoma of the Gallbladder]. 2680 59

Somatostatin receptor 2A expression is a feature of well-differentiated neuroendocrine neoplasms and is important for their diagnosis and therapy. Little is known about somatostatin receptor 2A expression in poorly differentiated neuroendocrine neoplasms in relation to TP53 and RB1 status and how these features may contribute to the separation of well from poorly differentiated neuroendocrine neoplasms with a proliferation index above 20%. This study investigates the expression of somatostatin receptors, p53 and Rb1, and TP53 alterations in pancreatic and extrapancreatic well and poorly differentiated neuroendocrine neoplasms (Ki67-index >20%). Thirty-seven poorly differentiated neuroendocrine neoplasms of pancreatic (n=12) and extrapancreatic origin (n=25) as well as 10 well-differentiated neuroendocrine neoplasms of the pancreas (n=9) and rectum (n=1) with a Ki67-index >20% were immunostained for synaptophysin, chromogranin A, Ki67, CD56, p53, Rb1, ATRX, DAXX, progesterone receptor, somatostatin receptor 2A, somatostatin receptor 5, and cytokeratin 20, and sequenced for TP53, exons 5-9. Somatostatin receptor 2A was positive in 6/37 of poorly differentiated and in 8/10 of well-differentiated neuroendocrine neoplasms. One well-differentiated and two poorly differentiated neuroendocrine neoplasms expressed somatostatin receptor 5. Abnormal nuclear p53 and Rb1 staining was found in 29/37 and 22/37 poorly differentiated neuroendocrine neoplasms, respectively, whereas all well-differentiated neuroendocrine neoplasms showed normal p53 and Rb1 expression. TP53 gene alterations were restricted to poorly differentiated neuroendocrine neoplasms (24/34) and correlated well with p53 expression. All cases were progesterone receptor negative. Somatostatin receptor 2A expression is not limited to well-differentiated neuroendocrine neoplasms but also occurs in 16% of poorly differentiated neuroendocrine neoplasms from various sites. Most poorly differentiated neuroendocrine neoplasms are characterized by TP53 alterations and Rb1 loss, usually in the absence of somatostatin receptor 2A expression. In the pancreas, these criteria contribute to separate well-differentiated neuroendocrine neoplasms with a Ki67-index above 20% from poorly differentiated neuroendocrine neoplasms.
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PMID:Somatostatin receptor expression related to TP53 and RB1 alterations in pancreatic and extrapancreatic neuroendocrine neoplasms with a Ki67-index above 20. 2805 98