Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 69-year-old man complaining of longstanding hearing loss and mild otorrhea was found to have a mass obliterating the external auditory canal and polypous tympanic mucosa with accompanying absence of the tympanic membrane and ossicular chain. Tumors excised from the external auditory canal and tympanum showed histologic features essentially characteristic of a carcinoid tumor: a ribbon or festoon arrangement of tumor cells, formation of anastomosing cords and glandular spaces, presence of numerous argyrophilic as well as argentaffin secretory granules within many of the tumor cells, and ultrastructural evidence of neurosecretory granules in the tumor cell cytoplasm. Immunohistochemically, the tumor was found to contain not only neuronal marker substances such as neuron-specific enolase, S-100 protein and chromogranin A, but also serotonin and multiple peptide hormones such as pancreatic polypeptide, glucagon, cholecystokinin and leucine-enkephalin. A review of the pathology of 17 previous cases of carcinoid of the middle ear suggested that this type of carcinoid may have a variegated hormone profile among carcinoids of foregut origin, and hormonally may resemble ileal carcinoid arising from the midgut, although their histogenetic origins may differ, because of frequent production of serotonin.
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PMID:Carcinoid tumor of the middle ear containing serotonin and multiple peptide hormones. A case report and review of the pathology literature. 144 56

Primary carcinoid tumours of the middle ear are extremely rare, only nine cases having been reported. However, their true incidence is probably greater, since they are very difficult or impossible to distinguish from adenomas and adenocarcinomas with conventional histological stains. We describe the clinical, histological, immunohistochemical and ultrastructural findings in a carcinoid tumour of the middle ear in a 50-year-old woman. Immunohistochemical studies on non-neoplastic middle ear mucosa undertaken to investigate the histogenesis of such tumours are also reported. Histologically, the tumour consisted of both solid areas and areas of tubular structures containing intraluminal mucus. All the tumour cells reacted with the anti-keratin antibody KL 1; some were argyrophil and reacted with antibodies against neuron-specific enolase, chromogranin A, Leu-7, serotonin, pancreatic polypeptide, glucagon and lysozyme. Electron microscopy revealed dense core granules in the tumour cells. Endocrine cells could not be detected in non-neoplastic middle ear mucosa. Pancreatic-polypeptide-like immunoreactivity was demonstrated immunohistochemically in all three other published cases of carcinoid tumour of the middle ear investigated for this peptide, and glucagon-like immunoreactivity was also exhibited by one of these. Since carcinoid tumours of the middle ear often, as in this case, exhibit some degree of glandular differentiation, immunohistochemical or electron-microscopic investigation to detect neuroendocrine differentiation is of particular importance in adenomatous middle ear neoplasms.
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PMID:Carcinoid tumour of the middle ear. A morphological and immunohistochemical study with comments on histogenesis and differential diagnosis. 248 Dec 99

A primary tumor of the middle ear was examined histologically, histochemically, immunohistochemically and ultrastructurally. Neuroendocrine cell differentiation, a carcinoid feature, was demonstrated by the presence of numerous argyrophil granules, as well as positive serotonin, glicentin, glucagon, and human pancreatic polypeptide (hPP) granules in some of the Grimelium-positive cells. Chromogranin A was also detected in the cells, but much less frequently than Grimelius-positive staining. Neither neuron-specific enolase (NSE) nor epithelial membrane antigen (EMA) was demonstrated in the tumor. Mucin was demonstrated only intraluminally. Electron microscopy revealed many typical neurosecretory granules in tumor cells, but no apical mucin granules. The tumor appeared to be benign, and there has been no sign of recurrence during a postoperative period of one year.
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PMID:Carcinoid tumor of the middle ear. An immunohistochemical and electron microscopic study. Report of a case. 322 80

Carcinoid tumors of the middle ear are rare, with only three previously reported cases. The authors report the light and electron microscopic and immunohistochemical features of two carcinoid tumors that occurred in a 34-year-old female and a 21-year-old male. Both presented with unilateral hearing loss. By light microscopic examination, both were characterized by trabecula of tall columnar cells with basal nuclei and no mitotic activity. Electron microscopic examination demonstrated large numbers of pleomorphic neurosecretory granules, perinuclear aggregates of intermediate filaments, cell junctions, and surface microvillous processes. Some cells contained intermediate filaments forming tonofilaments and lacked secretory granules. These cells stained for cytokeratin by immunoperoxidase and separated the neuroendocrine cells from the underlying basal lamina. The cells in this tumor stained for the molluscan cardioexcitatory peptide. Cells in both tumors also stained for pancreatic polypeptide. Neither case stained for lysozyme, insulin, glucagon, somatastatin, gastrin, substance P, thyroid-stimulating hormone, adrenocorticotropic hormone, Met-enkephalin, Leu-enkephalin, neuropeptide Y, peptide YY, neurotensin, Bombesin, serotonin, neuron-specific enolose, glial and neural filaments, S-100 protein, cholecystokinin, beta-endorphin, beta-human chorionic gonadotropin, luteinizing hormone/follicle-stimulating hormone, vasoactive intestinal polypeptide, prolactin or calcitonin. Carcinoid tumor of the middle ear can be distinguished from paraganglioma and middle ear adenoma.
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PMID:Carcinoid tumors of the middle ear. 357 33

The immunocytochemical analysis of two cases of well-differentiated endocrine tumours (carcinoids) of the middle ear revealed predominant cell populations producing pancreatic polypeptide (PP)-related peptides, glucagon-related peptides, and serotonin (the latter only in one case). In consecutive sections PP- and glucagon-related immunoreactivities mainly colocalized in the same tumour cells. Ultrastructurally tumour cells were characterized by medium-sized to large granules of moderate to high density, on which PP and glicentin were localized by the immunogold technique. No amphicrine cells were found. These features are consistent with those of similar tumours in the rectal mucosa that are mainly composed of L cells coexpressing both PP-related and glucagon-related peptides. Additional tumour antigens of hindgut type detected immunohistochemically were prostatic acid phosphatase and CAR-5 mucin. Expression of the CAR-5 antigen was also found in samples of normal middle ear mucosa, in which endocrine cells have not been identified. In case 1 peritumoral mucosal invaginations showed a proliferation of endocrine cells identical immunophenotypically to tumour cells, possibly representing a precursor lesion. It is concluded that well-differentiated endocrine tumours of the middle ear are a distinct pathological entity characterized by multiple hormone production, typically involving three classes of hormones (pancreatic polypeptide-related peptides, glucagon-related peptides, and serotonin) of the hindgut endocrine system.
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PMID:Well-differentiated endocrine tumours of the middle ear and of the hindgut have immunocytochemical and ultrastructural features in common. 759 94

A recurrence of a primary carcinoid tumor of the middle ear 15 years after radical tympanomastoidectomy is reported. An extended subtotal petrosectomy using a craniocervical approach with temporary infracondylar mandibulotomy was performed, since imaging studies demonstrated an extensive tumor with a close relationship to the tegmen tympani, facial nerve, and ascending and horizontal portions of the carotid canal. The tumor was metabolically inactive. Histopathological examination showed a solid, trabecular tumor that was positive for pancytokeratin Lu5, neuron-specific enolase, pancreatic intestinal polypeptide and glucagon. Neuroendocrine-granules were demonstrable under electron microscopy. This case is reported to show that primary middle-ear carcinoid tumors can recur years after radical tympanomastoidectomy.
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PMID:Treatment of a local recurrence of a carcinoid tumor of the middle ear by extended subtotal petrosectomy. 955 Feb 56

Middle ear adenoma (MEA) is a rare tumor postulated to take origin from the lining epithelium of the middle ear cavity. The authors report on a case of MEA arising in a 53-year old woman suffering from a sensation of fullness in her left ear, otalgia, and light left-sided hearing loss. Histopathologically, the lesion was composed of cuboidal and polygonal cells displaying a trabecular, tubulo-glandular, and solid pattern of growth. Immunohistochemically, neoplastic cells diffusely stained with anti-vimentin antibodies and were focally positive for chromogranin A, neuron-specific enolase, lysozyme, and cytokeratins AE1/AE3. The majority of tumor cells showed weak and diffuse staining with both anti-PP and anti-ACTH antibodies and intense positivity with anti-glucagon and anti Leu-7 antibodies. Ultrastructural investigation revealed both mucinous-glandular and neuroendocrine differentiation. The authors suggest that the appropriate terminology would be adeno-carcinoid or amphicrine tumor of the middle ear rather than "adenoma," a term that does not reflect its dual nature.
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PMID:Middle ear adenoma is an amphicrine tumor: why call it adenoma? 1129 23