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

Spontaneously occurring and chemically induced pheochromocytomas are rare in mice. That the mouse pheochromocytoma is a more appropriate animal model than that of the rat for study of human medullary adrenal tumors has been suggested. The expression of phenylethanolamine-N-methyltransferase (PNMT), the enzyme responsible for production of epinephrine from norepinephrine, is common to both mouse and human pheochromocytomas. This investigation assessed the expression of the immunohistochemical markers PNMT, tyrosine hydroxylase (TH), and chromogranin A (CGA) in spontaneously occurring and chemically induced pheochromocytomas in the B6C3F1 mouse. Spontaneous tumors were derived from control animals from 10 different studies and the pheochromocytomas from treated groups from 4 different studies. All tumors were positive for maximal TH expression. A highly significant difference in PNMT expression (p < 0.01) occurred between spontaneously occurring pheochromocytomas classified as benign or "malignant" by the criteria of toxicologic pathology. Chemically induced tumors showed intermediate PNMT staining. A marked reduction in CGA expression occurred in pheochromocytomas induced by technical grade pentachlorophenol, compared to the other three chemicals and the spontaneously occurring tumors. These findings suggest that immunohistochemistry is a reliable tool in investigating the functional capabilities of pheochromocytomas in mice. PNMT expression is a tightly regulated component of the chromaffin cell phenotype and appears to be readily lost in mouse pheochromocytomas, particularly those with aggressive characteristics.
 ...
PMID:A comparative immunohistochemical study of spontaneous and chemically induced pheochromocytomas in B6C3F1 mice. 1274 66

A 24-year-old female rhesus macaque (Macaca mulatta) presented with a clinical history of chronic heart disease and prolonged recovery from sedation and anesthesia. At necropsy, the heart was markedly enlarged, with thinned ventricular walls, dilated chambers, and severe left atrioventricular valvular insufficiency. The ventricular walls contained numerous narrow, pale, often coalescing streaks that often extended along vessels into the deeper myocardium. Histologically, bands of interstitial fibrosis in the heart were associated with areas of myofiber atrophy, myofibril degeneration and loss, and inflammation. The left adrenal gland contained a 2 x 1 x 0.5 cm tumor with an unusual angiomatous pattern consisting largely of blood-filled sinusoids lined by one to four layers of low cuboidal to polyhedral tumor cells. In most sinusoids, the tumor cells appeared to be in direct contact with blood, although endothelial cells lined some sinusoids. Ultrastructurally, the tumor cells contained abundant electron-dense cytoplasmic granules. These granules were argyrophilic by Sevier-Munger staining and intensely immunoreactive for synaptophysin, chromogranin A, neuron-specific enolase, and S-100. These findings helped confirm the diagnosis of angiomatous pheochromocytoma. The heart lesions match those reported for catecholamine cardiomyopathy in other species.
 ...
PMID:Cardiomyopathy associated with angiomatous pheochromocytoma in a rhesus macaque (Macaca mulatta). 1282 20

A 52-yr-old woman presented with hypertension, elevated urinary vanillylmandelic acid, metanephrines, normetanephrines, and plasma chromogranin A (CgA), but normal urinary catecholamine levels. Abdominal ultrasonography and subsequent MRI imaging showed a 3 cm nodular lesion of the right adrenal gland also visualized by 123I-meta-iodobenzylguanidine scintigraphy consistent with a pheochromocytoma (PC). Her OctreoScan was negative. The patient underwent right adrenalectomy and histological examination showed a PC. The adrenal medulla tissue was examined for somatostatin (SRIH) receptor subtypes 1 to 5 (SSTR1 to 5) expression by RT-PCR. Cultured tumor cells were treated with either SRIH, Lanreotide (Lan), or an SSTR2 (BIM-23 120) or SSTR5 (BIM-23 206) selective agonist. CgA secretion was measured in the medium by ELISA and catecholamine levels by HPLC after 6h. Cell viability was assessed after 48h. RT-PCR analysis showed that SSTR1, 2, 3 and 4 were expressed. CgA secretion was significantly reduced by SRIH (- 80 %), Lan (- 35 %), and the SSTR2 selective agonist (- 65 %). Norepinephrine secretion was reduced by SRIH (- 66 %), Lan (- 40 %), and BIM-23 120 (- 70 %). Epinephrine and dopamine secretion was also inhibited by treatment with SRIH (- 90 % and - 93 %, respectively) and BIM-23 120 (- 33 % and - 75 %, respectively) but not by Lan. Cell viability was also significantly reduced by SRIH (- 30 %), Lan (- 10 %), and the SSTR2 selective agonist (- 20 %). The SSTR5 selective agonist did not modify either CgA and catecholamine secretion or cell viability. Our data show that SSTRs may be present in a PC although OctreoScan is negative in vivo, and that SRIH and its analogs may reduce both differentiated and proliferative functions in chromaffin cells in vitro. These findings suggest that SRIH analogs with enhanced SSTR2 affinity might be useful in the medical therapy of PC, even when an OctreoScan is negative.
 ...
PMID:An in vivo OctreoScan-negative adrenal pheochromocytoma expresses somatostatin receptors and responds to somatostatin analogs treatment in vitro. 1292 Jun 56

We report a potential pitfall of 123I-metaiodobenzylguanine (MIBG) scan. Magnetic resonance imaging performed for other reasons, showed 2.5 cm tumor in the left adrenal gland. On questioning patient had episodic palpitations, flushing and hypertension suggestive of pheochromocytoma. Urinary metanephrine level was of borderline value but serum chromogranin A level was clearly elevated. 123I-MIBG scan showed accumulation of the tracer in the upper left abdomen and the finding was suspected to be intra-adrenal pheochromocytoma. During operation two separate tumors, adrenocortical adenoma in the left adrenal gland, and another smaller, extra-adrenal paraganglioma locating very close to the adenoma, were found. Thus the positive MIBG finding was caused by a paraganglioma with the concurrent presentation of nonfunctioning adrenocortical adenoma.
 ...
PMID:A pitfall of metaiodobenzylguanidine scan: paraganglioma in close proximity to adrenocortical adenoma. 1295 37

We report the case of a 52-yr-old man with a mass in the area of the left adrenal. The clinical features, MIBG uptake, and elevated urinary dopamine levels suggested the diagnosis of pheochromocytoma. He presented with unstable hypertension, tachycardia, weight loss, and the "inflammatory syndrome" (fever, leukocytosis, and high sedimentation rate). Clinical findings, preoperative radiographic (sonography, CT scan, [131I]MIBG scintigraphy), and endocrine evaluations (elevated 24-h urinary dopamine) were suggestive of a dopamine-secreting adrenal tumor. The mass was resected and on histologic examination showed the characteristic features of a malignant fibrous histiocytoma (MFH). The tumor cells were immunopositive for neuron-specific enolase (NSE), vimentin, CD-68, S-100, desmin, and immunonegative for chromogranin A, synaptophysin, neurofilament protein, and low-molecular-weight keratin, indicating that this tumor was not able to synthesize catecholamines. The prolonged retention of the tracer (MIBG) was interpreted as a consequence of obstructive hydronephrosis, while elevated urinary dopamine levels were assumed to be due to compression of the renal vessels by the large retroperitoneal mass.
 ...
PMID:Retroperitoneal malignant fibrous histiocytoma mimicking pheochromocytoma. 1524 9

A pigmented "black" mass was discovered incidentally in a 72-year-old woman. The tumor, which was detected near the upper pole of the left kidney, was cystic and intensely black throughout with the presence of abundant, coarse, dark brown to black pigment granules. Histologic examination showed a proliferation of monomorphous neoplastic cells arranged in a typical zellballen growth pattern. These features indicated a diagnosis of pheochromocytoma. Immunostains for chromogranin A, synaptophysin, and neuron-specific enolase were positive. The immunostain for HMB-45 was negative. Electron microscopy showed neurosecretory-type granules and larger pleomorphic granules, which were considered most consistent with neuromelanin, a waste product of catecholamine metabolism. The evidence of melanin or melanin-like pigment in the adrenal gland has been described in only 10 cases in the literature and is always a microscopic finding. The case reported here is unique for the characteristic black macroscopic appearance and the abundance of pigment.
 ...
PMID:Pigmented "black" pheochromocytoma of the adrenal gland: a case report and review of the literature. 1538 89

A 32-year-old asymptomatic female was diagnosed with an isolated thyroid nodule of 2.5 cm diameter. Fine needle aspiration suggested a medullary thyroid carcinoma. Consequently, a total thyroidectomy was performed. The nodule stained positive for chromogranin A, neurone-specific enolase and synaptophysin, but not for calcitonin. Finally, pathological analysis showed a thyroid paraganglioma. Although the tumour appeared to be sporadic in a patient with no personal or familial history of paraganglioma and/or pheochromocytoma, we have identified a new mutation (392delC) of the succinate dehydrogenase-B (SDHB) gene in the genomic DNA extracted from the leukocytes of the patient. That mutation induced a shift in the reading frame of the gene creating a premature stop codon (P131fsX135) which was predicted to result in a truncated SDHB protein of 135 amino acids. This report highlights the difficulties of this unexpected diagnosis of hereditary thyroid paraganglioma. It also discusses the clinical involvements in terms of familial screening and the necessary follow-up of the patient.
 ...
PMID:A thyroid nodule revealing a paraganglioma in a patient with a new germline mutation in the succinate dehydrogenase B gene. 1547 41

There is evidence for a close interrelation between the adrenomedullary and adrenocortical tissues, and there are well-characterized models of their paracrine interaction. To contribute to the studies of systemic interactions between these tissues, we studied a 52-year-old female patient with a pheochromocytoma and a contralateral cortisol-producing adenoma. Due to a misunderstanding, she presented to her family doctor to have an inherited kidney disease ruled out. An adrenal mass was discovered incidentally by ultrasound. A computerized tomography of the abdomen revealed bilateral adrenal masses. Due to excess catecholamine secretion, bilateral pheochromocytomas based on multiple endocrine neoplasia syndrome were suspected. Laboratory work-up, selective adrenal venous sampling and magnetic resonance imaging studies established the diagnosis of a pheochromocytoma in the right-hand adrenal gland and a cortisol-producing adenoma on the left. Simultaneous bilateral laparoscopic subtotal adrenalectomy was performed. Immunohistochemistry showed positive staining against chromogranin A in a histological specimen obtained from the right-hand adrenal gland, while the left was negative; the left-hand adrenal gland stained positive against the ACTH receptor (MC2R) while the right was negative. Genetically, the patient was negative for MEN2, von Hippel-Lindau disease, and mutations in subunits B, C, and D of the succinate dehydrogenase gene. Although presence of bilateral adrenal adenomas or bilateral adrenal pheochromocytomas in certain inherited disorders are possible, this rare case of an adrenal pheochromocytoma combined with a contralateral cortisol-producing adrenal adenoma may further underline the wide range of complex interactions between the two endocrine systems.
 ...
PMID:Adrenal pheochromocytoma with contralateral cortisol-producing adrenal adenoma: diagnostic and therapeutic management. 1600 33

Neuroendocrine (NE) tumors such as medullary thyroid cancer, carcinoid, small cell lung cancer and pheochromocytoma are metastatic in nature, and secrete biogenic amines and hormones. In this review, we will discuss the possibility that activation of the Ras/Raf signaling pathway may be a therapeutic target for patients with select NE tumors. In-vitro activation of Raf-1 in NE tumors either by expression of the ectopic catalytic domain of Raf-1 or by a pharmacologic drug, ZM336372, resulted in growth inhibition. In addition, activation of the Ras/Raf pathway led to a significant reduction in NE markers such as serotonin, chromogranin A and calcitonin. These data support development of Raf-1-activating compounds for treatment of patients with NE tumors of selective subtypes.
 ...
PMID:The Raf-1 pathway: a molecular target for treatment of select neuroendocrine tumors? 1642 31

A 63-year-old male patient was admitted for the treatment of malignant pheochromocytoma with multiple liver metastases. Plasma and urinary levels of catecholamines were elevated. Transcatheter arterial embolization (TAE) with concomitant administration of mitomycin C and gelatin sponge was performed for the treatment of liver metastases. Dose of alpha-1 blocker before TAE was increased to prevent hypertensive crisis during and after TAE. The hepatic metastatic lesion of CT findings was decreased after TAE. Although blood pressure showed a transient hypertension (180/100 mmHg) after every TAE, it returned rapidly to normal. The patient experienced transient abdominal pain, nausea, and loss of appetite after every TAE; however, those symptoms were readily controlled by conventional medications. Slight elevation of liver transaminases was recognized but returned to normal range within 3 weeks. No other major side effects were seen with TAE. While plasma and urinary level of catecholamines were unchanged, plasma chromogranin A (CgA) level was significantly decreased. These results suggest that TAE is a useful treatment for hepatic metastases. Plasma CgA level is a useful marker in the treatment of malignant pheochromocytoma.
 ...
PMID:Transcatheter arterial embolization for the treatment of liver metastases in a patient with malignant pheochromocytoma. 1654 73


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>