Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two patients developed sinonasal small-cell neoplasms that arose 22 years and 37 years, respectively, following radiotherapy for bilateral retinoblastomas. The tumors were composed of small cells with scant cytoplasm and had a few scattered Homer-Wright rosettes. Immunohistochemically, one tumor was positive for keratin (CAM 5.2 and AE1/AE3), epithelial membrane antigen, and neuron-specific enolase. The other neoplasm was immunoreactive for keratin (CAM 5.2 only) and neuron-specific enolase; it also had focal immunopositivity for S-100 protein, desmin, and muscle-specific actin. Both were negative for CEA, vimentin, melanocyte-specific antigen (HMB45), chromogranin A, synaptophysin, Leu-7, 200 kd neurofilament, and retinal S-antigen. Despite aggressive multimodal therapy, the patients died of metastatic tumor 7 months and 10 months following their initial diagnosis, respectively. Although osteosarcoma is the most frequent second cancer following bilateral retinoblastomas, some patients develop clinically aggressive sinonasal small-cell tumors that are difficult to place into conventional classifications. Both of our cases showed evidence of multidirectional differentiation; one tumor labeled with epithelial and neural markers, and the other expressed epithelial, neural, and myogenous antigens.
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PMID:Unusual sinonasal small-cell neoplasms following radiotherapy for bilateral retinoblastomas. 267 54

We report 22 examples of an unusual and distinctive benign mesenchymal tumor arising exclusively from lymph nodes of the groin. The tumor, which presents clinically as a swelling, is composed of spindled cells arranged in solid sheets or short, vaguely palisaded fascicles similar to a neurilemoma. The spindled cells blend gradually with large mats of eosinophilic material that appear as thick bands, ellipses, or circular profiles, depending on the plane of section. These eosinophilic structures, which represent a highly characteristic feature of the tumor, contain deeply eosinophilic, collagen-rich cores surrounded by a weakly eosinophilic, actin-rich cuff. The actin within these eosinophilic structures is derived by coalescence of intracellular actin globules extruded from neighboring cells. In all cases, a thin, compressed rim of normal lymph node was identified. Immunohistochemical analysis indicates that the cells express actin but lack S-100 protein, synaptophysin, desmin, keratin, and epithelial membrane antigen. Delicate, linear striations were identified in only two cases by conventional histochemical techniques. The foregoing features suggest that the tumor is related to a myofibroblast or a specialized smooth-muscle cell. These tumors, therefore, probably arise from smooth-muscle-like cells, which are normally present in some lymph node capsules or stroma. Follow-up information on 17 patients indicated that all are alive and well without any evidence of recurrence or metastasis.
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PMID:Palisaded myofibroblastoma. A benign mesenchymal tumor of lymph node. 271 86

We report herein the clinicopathological, immunohistochemical and ultrastructural studies on 13 female patients and one male patient with papillary cystic tumors of the pancreas. Their ages ranged from 12 to 60 (mean 25) years. Most patients complained of abdominal mass or abdominal pain. Following complete resection of the tumor, all have remained well for between 3 months and 19 years (maen 5 years). In one patient the tumor was malignant and, 10 years after the initial partial resection, there was a recurrence with involvement of the colon, metastasis to the lymph nodes and venous invasion. Immunohistochemically, most tumor cells were positive for neuron specific enolase, synaptophysin, alpha-1-antitrypsin and vimentin and sometimes for the estrogen receptor related antigen, ER-D5, and the oncogen product of c-Ha-ras, c-Ha-ras P21. Ultrastructurally there were zymogen-like intracytoplasmic granules, intercellular junctions and intercellular spaces. These results support the hypothesis that the tumor originates from undifferentiated cells capable of differentiation toward acinar, endocrine or ductular cells. Estrogen and the c-Ha-ras oncogene presumably are linked to the development.
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PMID:Papillary cystic tumor of the pancreas: an immunohistochemical and ultrastructural study of 14 patients. 273 63

Synaptophysin, a membrane glycoprotein of presynaptic vesicles, and neurofilament (NF) proteins were tested as immunohistochemical markers for neuroendocrine tumors. Synaptophysin was consistently present in the tumor cells of pheochromocytomas (10/10), thyroid medullary carcinomas (8/8), and pancreatic islet cell tumors (6/6). Most gastrointestinal and thoracic carcinoid tumors (12/13) were positive, as were neuroendocrine carcinomas (7/9), of which two Merkel cell carcinomas were negative. The NF proteins were present in all pheochromocytomas, in three thoracic and one gastric carcinoid tumors, in four of eight thyroid medullary carcinomas, and in five of six pancreatic islet cell tumors. All intestinal carcinoids were negative for NF proteins, as were neuroendocrine carcinomas, except for two Merkel cell carcinomas that were positive. The 68-kilodalton (kd) NF subunit protein was the most prevalent in all NF-positive neuroendocrine tumors, and the 160-kd subunit was relatively often present, although in a smaller number of cells. The 200-kd NF subunit protein was regularly found in pheochromocytomas and only occasionally found in other neuroendocrine tumors. A series of nonneuroendocrine tumors, such as adenocarcinomas, sarcomas, lymphomas, and melanomas, were negative for both synaptophysin and NF proteins. Thus, synaptophysin is a specific and fairly sensitive marker for neuroendocrine tumors of both low and high grades of malignancy. The NF proteins are good markers for pheochromocytoma, and their presence is of basic tumor biologic interest and of potential diagnostic value in other neuroendocrine neoplasms.
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PMID:Synaptophysin and neurofilament proteins as markers for neuroendocrine tumors. 282 Mar 44

Renal tumors of childhood occasionally exhibit histopathologic and clinical features that preclude accurate diagnosis. Molecular and cell culture techniques may be helpful in better characterizing these cases. This approach was used to examine unusual bilateral renal tumors from a young boy. The left kidney tumor was an undifferentiated neoplasm with light microscopic features suggestive of both Wilms' tumor and neuroblastoma, and the right kidney tumor was identified as multilocular cystic nephroma (MLCN). In vitro tissue culture of tumor cells and hybridization experiments with an N-myc oncogene DNA probe contributed to a revised diagnosis of intrarenal neuroblastoma of the left kidney. A cell line established from the left tumor exhibited neurite outgrowth and was positive for neuron-specific enolase and synaptophysin. N-myc was greater than ten-fold amplified in chromosomal DNA from the left kidney tumor. Measurement of N-myc RNA expression enabled distinction between benign and malignant tumor tissue. The detection of N-myc gene amplification predicted a poor prognosis which was confirmed by the patient's subsequent clinical course.
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PMID:N-myc oncogene expression in histopathologically unrelated bilateral pediatric renal tumors. 283 41

The histology, histochemistry, and ultrastructure of 43 VIP-producing tumors (34 from the pancreas, one jejunal, six retroperitoneal and two mediastinic), 37 of which were associated with the WDHA syndrome, have been investigated on paraffin sections of primary or metastatic tumor tissue. The pancreatic and jejunal tumors showed all structural and secretory patterns of epithelial endocrine tumors, including expression of cytokeratin, neuroendocrine markers like neuron-specific enolase, chromogranins and synaptophysin, peptides like VIP, PHM, GRH, PP, insulin, neurotensin, glucagon, somatostatin and enkephalin, secretory granules, small clear vesicles, peculiar osmiophilic bodies, and occasional formation of tubules or microacini with specialized luminal surfaces. All the remaining tumors were neurogenic, showing either neurons and nerve fibers together with Schwann cells (ganglioneuromas and ganglioneuroblastomas) or endocrine cells (pheochromocytomas) reacting with VIP, PHM, NPY, enkephalin, somatostatin, neuron-specific enolase, synaptophysin, and MAP2 (but not cytokeratin, PP, or GRH) antibodies. A possible origin of pancreatic VIPomas from transformed pancreatic PP cells or ductular stem cells partially committed to differentiation along the PP cell line is suggested.
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PMID:The morphology and neuroendocrine profile of pancreatic epithelial VIPomas and extrapancreatic, VIP-producing, neurogenic tumors. 283 87

Small-cell carcinomas of the lung (SCLCs) are frequent tumors of the bronchopulmonary tract which are distinguished by their neuroendocrine (NE) features, indicative of a derivation from the sparse neuroendocrine cells present in the normal epithelium. Because of the lack of marked morphological details, the differential diagnosis of this tumor is very difficult. We show that the epithelial nature and origin of SCLCs can be demonstrated, biochemically and immunocytochemically, by the expression of cytokeratins, notably cytokeratins 8 and 18, often together with desmosomal proteins as another independent differentiation marker. The NE character of SCLCs, on the other hand, is revealed by antibodies to certain NE-specific components, notably the broad range NE marker, the membrane protein synaptophysin. Both kinds of differentiation markers are also expressed in a number of SCLC-derived cultured cell lines which therefore may serve as valuable biological model systems to study the biology of SCLC.
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PMID:Differentiation markers as an aid in the histological diagnosis of small-cell carcinoma of the lung: synopsis of intermediate filament protein and synaptophysin expression. 284 53

Fifteen cerebellar hemangioblastomas were examined by immunohistochemistry for expression of neuron-specific enolase (NSE) and various neuropeptides using the avidin-biotin-complex peroxidase reaction with the following antibodies: NSE, synaptophysin, serotonin, substance P, vasoactive intestinal peptide (VIP), neuropeptide YY, neurotensin, and leu-enkephalin. In all tumor biopsies most of the stromal cells were positive for NSE. About 30% of the stromal cells showed a weak cytoplasmic synaptophysin positivity. Approximately 25% of the stromal cells were labeled with antibodies against substance P and neuropeptide YY. The partly strong reactivity was localized preferentially in perinuclear regions. These positive cells were mainly distributed in small cell clusters but were also scattered in the tumor parenchyma. In all tumor biopsies scattered cells exhibited strong perinuclear enkephalin positivity, corresponding probably to mast cells, whereas stromal cells were entirely negative. For serotonin, VIP, and neurotensin no specific reaction was seen. On the basis of these findings it is proposed that hemangioblastomas have a neuroendocrine component.
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PMID:Histogenesis of stromal cells in cerebellar hemangioblastomas. An immunohistochemical study. 291 47

Synaptophysin is an integral membrane glycoprotein (Mr 38,000) that occurs in presynaptic vesicles of neurons and in similar vesicles of the adrenal medulla. By using a monoclonal antibody to this protein (SY38), we have found, by immunohistochemistry and immunoblotting, that an identical or similar protein is also expressed in neuroendocrine tumors of neural type, such as pheochromocytomas and paragangliomas. In addition, this protein occurs in certain neuroendocrine epithelial cells, such as pancreatic islet cells; in a variety of neuroendocrine epithelial tumors, including isletcell adenomas and carcinomas and several carcinoids and neuroendocrine carcinomas of the gastrointestinal and the bronchial tracts; and in medullary carcinomas of the thyroid. Our results show that synaptophysin, and the vesicles that contain it, can occur in normal and neoplastic neuroendocrine cells of neural type, as demonstrated by colocalization with neurofilaments, as well as in those of epithelial type, as shown by colocalization with cytokeratin filaments and desmoplakins. We conclude that synaptophysin is expressed independently of other neuronal differentiation markers and propose that it be used as a differentiation marker in tumor diagnosis.
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PMID:Synaptophysin: a marker protein for neuroendocrine cells and neoplasms. 301 Mar 2

Stereotactic biopsies were obtained from a tumor in the pineal gland of a 37 year old man. Histological and smear preparations were studied using conventional staining techniques as well as immunocytochemical methods with monoclonal antibodies to glial fibrillary acidic protein (GFAP), the neurofilament proteins (NFP), the presynaptic vesicle protein synaptophysin as well as with antisera to neuronal specific enolase (NSE). The tumor was classified as a pineocytoma. The tumor cells uniformly contained no cytoplasmic GFAP but NFP, NSE and synaptophysin as shown by the immunocytochemical techniques. The pineocytoma could thus be subclassified as a pineocytoma with neuronal differentiation. The patient subsequently succumbed due to a hemorrhage into the tumor and autopsy confirmed the biopsy findings. We conclude that immunocytochemical techniques may prove invaluable in the subclassification of tumors of the pineal region.
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PMID:Pineocytoma with neuronal differentiation demonstrated immunocytochemically. A case report. 311 Nov 71


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