Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0031511 (pheochromocytoma)
 14,622 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A malignant pheochromocytoma with multiple metastases was diagnosed in a 7-year-old male wolfdog that resulted from a cross between an eastern timber wolf (Canis lupus lycaon) and an Alaskan malamute. A yellowish white neoplastic mass approximately 10 cm diameter was found in the right adrenal gland. The neoplasm penetrated through the wall of the caudal vena cava. A diagnosis of pheochromocytoma was established by histopathologic and immunohistochemical procedures. Immunohistochemically, the neoplastic cells expressed chromogranin A, substance P, synaptophysin, Leu-7, protein gene product 9.5, methionine-enkephalin, S100 protein, and galanin. Multiple metastatic tumors were found in the kidneys, spleen, lungs, heart, and liver.
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PMID:Immunohistochemical evaluation of a malignant phecochromocytoma in a wolfdog. 1146 80

Since the development of the first immunoassay for circulating chromogranin A in 1984, a lot of studies have evaluated its clinical impact in neuroendocrine tumors. Initially studied in pheochromocytoma patients, the clinical impact of chromogranin A has rapidly extended to most neuroendocrine tumours, sometimes in combination with other eutopic or ectopic secretions. In our experience, CgA demonstrates a variable sensitivity between NET primary and a high specificity. Our results suggest that CgA should be routinely screened in foregut-derived NET and abandoned in the routine screening of medullary thyroid carcinoma. In addition, in phaeochromocytoma and ileum-NET patients, CgA demonstrates a comparable sensitivity with urinary reference markers and its impact on the follow-up will form a key point when recommending routine screening. Both tumor burden and secretory activity should be taken into account when interpreting CgA results.
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PMID:Impact of chromogranin A measurement in the work-up of neuroendocrine tumors. 1176 57

Patients with neurofibromatosis type 1 (NF1) show an increased frequency of pheochromocytomas. The NF1 gene encodes a GTPase-activating protein that controls the activity of ras proteins in intracellular signaling. A mouse strain with a knockout mutation of Nf1, the murine counterpart of NF1, has recently been constructed. This mutation, designated Nf1(n31), has been shown to be associated with the frequent development of pheochromocytomas in heterozygous animals. Pheochromocytomas are extremely rare in wild-type mice. We have characterized the tumors to assess their relevance as a model for human pheochromocytomas. The frequency of pheochromocytomas was determined in inbred compared to outbred mice carrying the Nf1(31) mutation. Paraffin sections of pheochromocytomas from seven mice were stained immunohistochemically for the catecholamine biosynthetic enzymes, tyrosine hydroxylase (TH), and phenylethanolamine-N-methyltransferase (PNMT) to infer their profiles of catecholamine synthesis, and for chromogranin A (CGA) to infer their content of secretory granules. Cultured cells from a representative tumor were studied in vitro to assess proliferation and neuronal differentiation. Pheochromocytomas arose in approx 15% of Nf1(n31) mice with a mixed genetic background, but were absent in inbred mice. Approximately one-fourth of the tumors were bilateral. The tumors exhibited variable morphology. All included cells that appeared well differentiated and resembled normal chromaffin cells in that they expressed TH, PNMT, and CGA. Focal neuronal differentiation was also observed. In cell culture, the tumor cells ceased to proliferate and the majority underwent terminal differentiation into TH-positive cells with neuronal morphology. The phenotype of pheochromocytomas in mice with the Nf1(31) mutation resembles that of human pheochromocytomas, particularly with respect to their ability to produce epinephrine, as inferred from positive staining for PNMT. The tumors also resemble both normal and neoplastic human adrenal medulla with respect to their extensive differentiation into neuron-like cells in vitro. This change in phenotype may be related to ras activation. These neoplasms may be valuable both as models for the pathobiology of adrenal medullary neoplasia, and as a source of epinephrine-producing pheochromocytoma cell lines, for which adequate models currently do not exist.
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PMID:Characterization of Pheochromocytomas in a Mouse Strain with a Targeted Disruptive Mutation of the Neurofibromatosis Gene Nf1. 1211 14

Pheochromocytomas and paragangliomas arise from the adrenal glands and extraadrenal paraganglia, respectively. Malignant behavior of these tumors is uncommon and is, in part, dependent on their sites of origin, such as extraadrenal location. Morphologic criteria for malignancy of pheochromocytoma and paragangliomas have not been clearly defined. In this study, to clarify the histologic features that distinguish the benign from malignant pheochromocytomas and paragangliomas, we examined metastatic and nonmetastatic tumors using immunohistochemical techniques. A total of eight cases, five pheochromocytomas from the adrenal glands (four benign and one malignant tumor) and three paragangliomas with invasion or metastasis, were studied. The markers used in this study were chromogranin A, synaptophysin, NCAM (CD56), SNAP25, neuron-specific enolase, S-100 protein, and MIB-1. Our results suggest that MIB-1 immunostaining is a useful adjunct marker to predict malignant behavior in these tumors.
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PMID:Prediction of malignant behavior of pheochromocytomas and paragangliomas using immunohistochemical techniques. 1216 64

The neuropeptide pituitary adenylyl cyclase-activating polypeptide (PACAP) has been reported to be a potent regulator of chromaffin cell activity. In particular, PACAP stimulates catecholamine biosynthesis as well as the expression of various genes, including chromogranin A, neuropeptide Y, enkephalins, vasoactive intestinal polypeptide, and PACAP itself. The mechanisms involved in the effects of PACAP on chromaffin cells have been investigated using rat pheochromocytoma PC12 cells. This cell line turned out to be a suitable model in which to study the neurotrophic activities of PACAP. Recent studies using transgenic mice have shown that in the sympathoadrenal system, PACAP acts as an "emergency response" cotransmitter involved in the regulation of insulin-induced hypoglycemia.
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PMID:Fast-breaking results on the PACAP/VIP/secretin peptide family in chromaffin cells. 1243 65

Histidine decarboxylase is one of the enzymes of the amine precursor uptake and decarboxylation system and is known to be distributed in mast cells and enterochromaffin-like cells. With the hypothesis that histidine decarboxylase expression is a marker for neuroendocrine differentiation, we studied the immunoreactivity of histidine decarboxylase in neuroendocrine cells and tumors of the thyroid gland, adrenal medulla, lung, and gastrointestinal tract. Formalin-fixed paraffin sections were subjected to immunohistochemistry using anti-histidine decarboxylase antibody, and the sensitivity and specificity were compared with those of conventional neuroendocrine markers (CD56, chromogranin A, synaptophysin, and neuron-specific enolase). Enterochromaffin or enterochromaffin-like cells, adrenal chromaffin cells, and thyroid C-cells were positive for histidine decarboxylase, and related tumors (carcinoid tumor, pheochromocytoma, medullary carcinoma) showed a high percentage of positive staining. Furthermore, we used the antibody to distinguish small cell lung carcinoma from non-neuroendocrine lung carcinoma and also to detect neuroendocrine differentiation in large-cell neuroendocrine carcinoma and gastrointestinal small-cell carcinoma. The anti-histidine decarboxylase antibody stained most small cell lung carcinoma (18 of 23, sensitivity 0.78), and was rarely reactive with non-neuroendocrine lung tumors (2 of 44; specificity, 0.95). These values were close to those obtained from CD56 staining (sensitivity/specificity, 0.87/0.98). Histidine decarboxylase was also positive for 6 of 12 large cell neuroendocrine carcinomas and 4 of 7 gastrointestinal small cell carcinomas. In conclusion, we demonstrated that histidine decarboxylase is useful to distinguish between small cell lung carcinoma and non-neuroendocrine carcinoma and to demonstrate neuroendocrine differentiation.
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PMID:Histidine decarboxylase expression as a new sensitive and specific marker for small cell lung carcinoma. 1252 16

An immunohistochemical study was carried out to differentiate between such neoplasms of the cortical and cerebral layers of the adrenal as adrenocortical tumor and pheochromocytoma. It used antibodies to chromogranin A, synaptophysin, vimentin, cytokeratin 8, pancytokeratin, carcinoembryonic antigen, epithelial membrane antigen, neurofilaments, alpha-fetoprotein, alpha-antitripsin and neuron-specific enolase. Chromogranin A and synaptophysin appeared to be immunohistochemical markers for pheochromocytoma since it responded negatively to vimentin and cytokeratin. Adenocortical tumors were associated with positive reaction to vimentin and a negative one to cytokeratin. These characteristics were used to differentiate adrenocortical tumors from adenomas which responded to cytokeratin and hardly to vimentin. A possibility of adrenal tumors consisting of endocrine and neurogenic cells is considered.
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PMID:[Immunohistochemical identification of hormonally-inactive tumors of the adrenal gland]. 1253 Feb 64

Adrenal incidentalomas are a heterogeneous group of pathological entities, including benign or malignant adrenocortical or medullary tumors, hormonally active or inactive lesions, which are identified incidentally during the examination of nonadrenal-related abdominal complaints. About 1.5% to 23% of adrenal incidentalomas are pheochromocytomas. Composite pheochromocytoma is a rare tumour of adrenal medulla with divergente clinical course. This type of pheochromocytoma is designated "composite" or "mixed," depending on whether pheochromocytoma and nonpheochromocytoma components show the same embryologic origin. Nonpheochromocytoma components found in the composite pheochromocytoma include ganglioneuroma, ganglioneuroblastoma, neuroblastoma, and malignant schwannoma. The biologic behavior of composite pheochromocytomas may be as difficult to predict as more traditional pheochromocytomas; based on the number of cases reported to date the presence of areas resembling ganglioneuroblastoma or neuroblastoma does not necessary indicate a poor prognosis. Some may behave in a malignant fashion with metastasis by a component of the tumour which has neural features. Pheochromocytomas and paragangliomas are well-defined entities. Some of their nonsporadic associations and unusual morphological appearances are not universally appreciated. We report on a rare association of left adrenal CP, with typical right adrenal phochromocytoma and retroperitoneal paraganglioma, and a review of literature. We analyzed the clinical and immunohistochemical features in a 24-year-old woman with composite pheochromocytoma localized in the left adrenal gland and associated with blood pressure of 200/140 mmHg. Abdominal computed tomography and 131-J MIBG revealed a 65 x 60 mm mass in the right adrenal gland, but no revealed 45 x 40 mm retroperitoneal mass and 20 x 20 mm mass in the left adrenal region. Serum and urinary adrenaline levels were high, and catecholamine levels in the blood sample of the selective adrenal vein, were also high. Bilateral adrenalectomy and retroperitoneal mass were surgically removed without complications. Clinical symptoms were absent 6 years after surgery. After surgery the patient gave birth to two healthy babies. Immunohistochemical analyses revealed that tumour cells of right adrenal pheochromocytoma and retroperitoneal paraganglioma were strongly positive for neurone specific enolase, synaptophisin and chromogranin A. The left adrenal tumour showed pheochromocytoma, ganglioneuroma and neuroblastoma components. Immunoreactivity of this tumour added several features to the wide immunohistochemical spectrum. This case demonstrates the indolent behavior of sporadic-type CP and retroperitoneal paraganglioma in an adult patient. Unusual morphological features of CP occur in a substantial number of cases and may cause diagnostic problems.
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PMID:[Pheochromocytomas as adrenal gland incidentalomas]. 1258 98

Incidentally detected adrenal tumors are a common finding during abdominal ultrasonography, computed tomography, and magnetic resonance imaging. Although most of these lesions are benign adenomas, adrenocortical carcinomas and metastases constitute 5% to 10% of all tumors. Adrenal biopsy may be helpful, but its diagnostic value is controversial and disputed, and prospective studies have not yet been performed. Therefore, the diagnostic accuracy of adrenal core biopsy was evaluated in a prospective multicenter study involving 8 surgical centers in Germany and Austria. A total of 220 biopsies from surgical specimens of the adrenal gland were punctured in an ex vivo approach and processed for pathohistologic diagnosis using paraffin sections, routine staining, and immunohistochemistry (keratin KL1, vimentin, S100 protein, chromogranin A, synaptophysin, neuron-specific enolase, D11, MiB-1, and p53 protein). The evaluating pathologist was blinded for clinical data from the patients. A total of 89 adrenal adenomas (40.5%), 22 adrenal carcinomas (10.0%), 55 pheochromocytomas (25.0%), 15 metastases (6.8%), 16 adrenal hyperplasias (7.2%), and 23 other tumors (10.5%) were studied. Nine cases were excluded due to incomplete data (n = 2) or insufficient biopsy specimen (n = 7). In the remaining 211 tumors, compared with the final diagnoses of the surgical specimen, bioptic diagnoses were absolutely correct in 76.8% of the cases, nearly correct in 13.2% of the cases, and incorrect in 10% of the cases. Pheochromocytomas were correctly diagnosed in 96% of the cases, cortical adenomas were correctly or nearly correctly reported in 91% of the cases, cortical carcinomas were correctly or nearly correctly reported in 76% of the cases, and metastases were correctly or nearly correctly reported in 77% of the cases. Of the 39 malignant lesions, only 4 were misclassified, 2 as benign and 2 as possibly malignant. This resulted in an overall sensitivity for malignancy of 94.6% and specificity of 95.3%. Our findings suggest that adrenal core biopsy is a useful method for identifying and classifying adrenal tumorous lesions if sufficient biopsy specimens can be obtained. However, in clinical practice it remains to be shown whether the benefits of biopsy outweigh the risks of the procedure.
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PMID:High diagnostic accuracy of adrenal core biopsy: results of the German and Austrian adrenal network multicenter trial in 220 consecutive patients. 1261 87

Secretin evokes catecholamine secretion from PC12 pheochromocytoma cells. We tested whether secretin activates transcription of the major vesicular core protein chromogranin A (CgA). Secretin stimulated both endogenous CgA gene transcription (approximately 4-6-fold) as well as transfected CgA promoter activity (approximately 8-10-fold; EC50, approximately 7 nm) in PC12 cells. Studies on CgA promoter 5'-deletion mutant/luciferase reporter constructs, point mutations of the CgA cAMP response element (CRE), and their transfer to a heterologous promoter implicated CRE in cis as both necessary and sufficient for secretin-stimulated CgA gene transcription. Secretin-induced CgA gene transcription was inhibited/abolished by cytosolic Ca2+ chelation, chemical blockade of phospholipase C, protein kinase A (PKA), or mitogen-activated protein (MAP) kinase extracellular signal regulated kinase (ERK) 1/2 and the expression of dominant negative mutants of ERK1/2, CRE binding protein (CREB) kinase RSK2, or CREB. Secretin also augmented (approximately 4-fold) phosphorylation of ERK1/2. Trans-activation (approximately 21-fold) of GAL4-CREB fusion protein by secretin indicates involvement of CREB in secretin signaling to gene transcription. Electrophoretic mobility shift assays also identified CREB as the mediator of secretin-induced CgA gene transcription, and pCREB supershifts indicated Ser-133 as the active CREB moiety in vitro. This conclusion was reinforced in vivo by results of chromatin pCREB immunoprecipitation assays. We conclude that secretin signals to CgA gene transcription through the CRE domain in cis and through cAMP, Ca2+, PKA, MAP kinase, and the transcription factor CREB in trans. Thus, multiple signal transduction pathways seem to subserve the function of stimulus-transcription coupling after this peptidergic stimulus to chromaffin cells.
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PMID:Secretin activation of chromogranin A gene transcription. Identification of the signaling pathways in cis and in trans. 1264 81


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