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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Long-time culturing of neuroendocrine tumors from gut and pancreas obtained by surgery was performed with the addition of different growth factors, such as nerve growth factor (NGF), fibroblast growth factor (FGF) and platelet derived growth factor (PDGF) to Hite's medium. Furthermore, the cells were also cultured on epithelial cell matrix (ECM) coated flasks with or without 5% fetal calf serum (FCS) supplemented to the medium. In ECM coated flasks the cells displayed a flattened, non-overlapping pattern and sometimes glandular formation. On the addition of 5% FCS to the culture medium single cells often appeared in cord-like pattern. Culturing in uncoated flasks led to free floating cell colonies or cell clusters attached to fibroblasts present. When different growth factors were added to tumor cells in uncoated culture flasks, no morphological difference could be noticed between the experiments. The tumor cells aggregated to big cell colonies, free-floating in the medium. However, the addition of growth factors to the culture medium showed varying degrees of positive silver staining in cultured tumor cells, while cells cultured in Hite's medium only, with or without FCS supplemented, were negative. The result might indicate that the cells cultured with growth factors retained their endocrine differentiation even after long-term culture. This observation correlated to positive immunostaining to chromogranin A and synaptophysin. Different growth factors might stimulate different fractions of tumor cells to retain the endocrine characteristics.
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PMID:In vitro culture of neuroendocrine tumors of the pancreas and gut. 247 21

A case of gangliocytic paraganglioma (GP) of the ampulla of Vater is reported and the literature reviewed, with special attention to immunohistochemical studies. The present case, which occurred in a 56-year-old woman, shows the typical histological admixture of epithelioid, ganglion and spindle cells. Immunohistochemistry reveals strong reactivity for synaptophysin, Leu-7, somatostatin, S-100 protein and vimentin. A few ganglion cells are reactive for neurofilaments. Chromogranin A, myelin basic protein, desmin and cytokeratin are absent. Immunohistochemical data from literature regarding the cytoskeletal composition of GPs are not unequivocal: cytokeratin and neurofilament positivity is reported by some authors and denied by others. More uniformity is reported concerning the peptides produced by GPs: somatostatin and pancreatic polypeptide are the most frequently found antigens, followed by serotonin. General neuroendocrine markers like neuron specific enolase and protein gene product 9.5 are always positive, whereas chromogranins are rarely found. S-100 protein is always positive in the spindle cell component. Our data are in keeping with those previously reported and add the diffuse positivity for the Leu-7 antigen and the positivity of ganglion cells for synaptophysin. The nature of the tumour is still a matter of debate and it is difficult to agree with either of the proposed hypotheses--hamartoma/choristoma versus true neoplasm. However the recent reports of the occasional malignant evolution of GPs may support their true neoplastic nature.
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PMID:Duodenal gangliocytic paraganglioma. Report of a case and review of the literature. 247 67

Acetone-fixed frozen sections of 15 malignant melanomas of the skin with metastases were studied immunohistochemically for the presence of different types of intermediate filament proteins, synaptophysin, muscle cell actins, and desmoplakins. One of the melanomas was a primary toe tumor, and the others mainly regional lymph node metastases. The original diagnosis of melanoma was reconfirmed in each case, and the melanoma diagnosis of the metastases was verified by S100 protein immunostaining in all cases and by a monoclonal antibody to melanoma cells (NK1C3) in 7 cases. All melanomas were prominently vimentin-positive. In 10 of 15 cases, immunoreactive keratin could be demonstrated with antibody CAM 5.2. The presence of keratins was confirmed in selected cases with three other monoclonal antibodies including AE1, PKK1, and a monoclonal antibody specific for keratin number 18. Desmoplakin, another marker of epithelial differentiation, was not found in melanoma cells. Two melanomas contained neurofilament-positive tumor cells, which were however negative for synaptophysin. Desmin, muscle actins, and glial fibrillary acidic protein were not found in the neoplastic cells. On the basis of the present results one could conclude that the protein composition of the cytoskeleton of melanomas is more complex than has been previously thought and most importantly that melanomas may contain keratins.
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PMID:Immunohistochemical spectrum of malignant melanoma. The common presence of keratins. 248 Nov 51

Tumor-derived GH3 rat pituitary cell lines are widely utilized to study mechanisms of prolactin secretion and responsiveness to secretagogues. These cells served here as a model with which to study relationships between shape and function. When GH3 cells were routinely grown in serum-supplemented medium, they exhibited the polygonal phenotype of epithelial cells, with scarce secretory granules. In contrast, when seeded in a serum-free medium, they attached loosely and contained more secretory granules. In both cases, they released prolactin in a nonpolarized manner. We show in the present work that laminin extracted from Englebreth-Holm-Swarm (EHS) tumors was a potent attachment and spreading factor for GH3/B6 cells seeded in serum-free medium. Moreover, it induced the formation of neurite-like processes, which were increased in number and length by chronic treatment with a specific secretagogue, thyroliberin (TRH). These changes in cell shape were correlated with a potentiation of prolactin secretion, both basal and TRH-stimulated. Furthermore, using immunocytochemistry and electron microscopy, we revealed--at the dilated tip of processes--an accumulation not only of prolactin, but also of synaptophysin, a vesicle membrane marker, and of several organelles, such as secretory granules, smooth vesicles, dense bodies and mitochondria. The cytoplasmic processes contained long parallel bundles of microtubules and showed a strong immunoreactivity for beta 2-tubulin. In addition, we found immunocyto-chemical evidence for the presence of 200-k Da neurofilament protein in GH3/B6 cell processes as well as in neurites of cultured hypothalamic neurons. We conclude that, in GH3/B6 cells, laminin induced the differentiation of neurite-like processes, which were the site of polarized organelle transport and exhibited some neuronal markers.
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PMID:Laminin induces formation of neurite-like processes and potentiates prolactin secretion by GH3 rat pituitary cells. 250 13

We studied by immunohistochemistry the features of differentiation in 24 desmoplastic and 16 classic medulloblastomas (median patient ages, 18 and 6.5 years, respectively) with the use of a panel of cytoskeletal and synaptosomal markers. A distinctive pattern of immunoreactivity with a series of monoclonal antibodies (Mabs) was documented in the polar tumor cells forming the reticulin-free pale islands of the desmoplastic variant, denoting overt neuritogenesis. These comprised the following: (1) Mab Tp-NFP1A3 recognizing an epitope in the high-molecular-weight (Mr) isoform of neurofilament protein; (2) Mab AP18 to the high-Mr microtubule-associated protein 2; (3) Mab TUJ1 recognizing the class III beta-tubulin isotype (human h beta 4); and (4) Mab SY38 to synaptophysin. Immunoblot analysis confirmed the expression of h beta 4 in three medulloblastomas, yielding strong single bands in two desmoplastic medulloblastomas and a considerably weaker band in one classic medulloblastoma. Glial fibrillary acidic protein-positive tumor cells frequently formed an integral component of the pale islands. Oligodendrogliallike areas in one classic and in three desmoplastic medulloblastomas were immunopositive for the Mabs to synaptophysin, microtubule-associated protein 2, and h beta 4, indicating a neuroblastic nature. We propose that the reticulin-free structures of desmoplastic medulloblastomas constitute neoplastic foci with features of predominantly neuronal and, to a lesser degree, astroglial differentiation.
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PMID:Cerebellar desmoplastic medulloblastomas. A further immunohistochemical characterization of the reticulin-free pale islands. 250 32

We carried out a histologic, immunohistochemical and ultrastructural study of 19 tumors, previously classified as Ewing's sarcoma of the bone (ESB). The tumors were categorized histologically into four groups according to the presence or absence and the distribution of Homer-Wright rosettes, together with the immunohistochemical and ultrastructural features: 1) neuroectodermal tumor of bone (NTB) with diffusely dispersed rosettes (4 cases), 2) conventional ESB totally lacking the rosettes (9 cases), 3) intermediate-type tumor with characteristics of both NTB and ESB (4 cases), and 4) spindle cell-type tumor with focal rosettes (2 cases). Ultrastructurally, NTB contained neurotubules and neurosecretory granules, whereas ESB consisted of only undifferentiated cells. Immunoreactivity with antineural antibodies, such as Leu-7, and those against synaptophysin, NSE, neurofilament, and chromogranin, was detected in the majority of NTB, in intermediate- and spindle cell-type tumors and in two of the nine cases of ESB. In view of these findings, we propose that use of the term "neuroectodermal tumor of the bone" should be restricted to tumors with an extensive distribution of rosettes, and that those without unequivocal rosettes should be classified as ESB, although ESB may be the most undifferentiated form of NTB and some overlap may occur between the two tumor types.
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PMID:Comparative study of neuroectodermal tumor and Ewing's sarcoma of the bone. Histopathologic, immunohistochemical and ultrastructural features. 255 84

Large cell neuroendocrine (LCNE) carcinomas of the lung are a newly recognized, highly aggressive and frequently misdiagnosed entity. We report a case of stage I LCNE lung carcinoma initially misdiagnosed as large cell undifferentiated carcinoma or poorly differentiated adenocarcinoma. The tumor was very extensively necrotic and its neuroendocrine differentiation was only demonstrable with immunohistochemical staining with PHE-5 monoclonal antibody and with antisera against synaptophysin and calcitonin. ACTH, somatostatin and neurofilaments were not demonstrable. The clinical course was ominous and the patient died within 17 months. The reason for this rapid fatal outcome could be ascribed either to the neuroendocrine phenotype of the tumor, or to the extensive necrosis, or both.
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PMID:Large cell neuroendocrine carcinoma of the lung. 255 26

Four examples of human cerebral medulloepithelioma were studied immunohistochemically with a panel of antibodies and antisera to neuronal and glial proteins. The tumors, in addition to primitive medullary epithelium, contained areas of neuroblastic, ganglionic, astrocytic, ependymoblastic and ependymal differentiation, and in one tumor, areas resembling polar spongioblastoma. Tumor cells throughout the primitive medullary epithelium displayed focal immunoreactivity for vimentin, glial fibrillary acidic (GFA) protein and for the neuron-associated class III beta-tubulin isotype. Neuroblasts showed immunoreactivity for the class III beta-tubulin isotype, microtubule-associated protein 2 and neuron-specific enolase. Immunoreactivity for neurofilament epitopes and synaptophysin was detected in areas of ganglionic differentiation and coincided with the demonstration of neurofibrils in Bielschowsky's silver impregnations. Vimentin was the only marker detected in ependymoblastic and ependymal rosettes or in areas of polar spongioblastoma, as well as in mesenchymal cells. The results indicate that, even in very primitive neoplastic neuroepithelium, immunocytochemical evidence of early commitment of some of the cells to a neuronal or glial lineage can be demonstrated. The neuron-associated class III beta-tubulin isotype appears to be one of the earliest markers indicative of neuronal differentiation in normal and neoplastic primitive neuroepithelium.
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PMID:An immunohistochemical study of the primitive and maturing elements of human cerebral medulloepitheliomas. 260 35

The left eye of an otherwise healthy child was enucleated at the age of 2 months because of an enlarging mass involving the temporal iris, ciliary body, and anterior retina. The initial histopathologic diagnosis was malignant medulloepithelioma with orbital extension. Closer study revealed a superotemporal chorioretinal and ciliary body coloboma; dysplasia of the adjacent retina; a glioneuromatous mass replacing the temporal ciliary body, chamber angle structures, and iris and extending through the sclera to involve the insertion of the lateral rectus muscle; neuroepithelial elements resembling medulloepithelioma; and abnormally developed iris pigment epithelium, and dilator and sphincter muscles. Immunohistochemistry demonstrated that the main mass consisted of neurons positive for neuron-specific enolase (NSE), synaptophysin and neurofilaments, and glial cells expressing vimentin, glial fibrillary acidic protein, and S-100 protein. The neuroepithelial elements reacted positively for cytokeratins and S-100 protein, in addition to NSE and vimentin, suggesting ciliary epithelial rather than embryonic retinal origin. The tumor was rediagnosed as glioneuroma, which in this case was part of a widespread colobomatous dysplasia of the anterior uvea and retina. The patient is alive without metastases or local recurrence 2 years following enucleation and subtotal removal of the lesion.
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PMID:Glioneuroma associated with colobomatous dysplasia of the anterior uvea and retina. A case simulating medulloepithelioma. 262 23

Twenty-one cases of cutaneous neuroendocrine (Merkel cell) carcinoma (CNEC) were examined by the ABC-immunoperoxidase method with a panel of antibodies to 5 intermediate filaments, 6 neuroendocrine-associated antigens, 6 peptide hormones, as well as melanoma-associated cytoplasmic antigen (HMB-45) and leukocyte common antigen. All tumors showed strong cytokeratin staining in characteristic dense, inclusion-like, cytoplasmic globules and in a reticular peripheral cytoplasmic pattern. Cytoplasmic coexpression of inclusions of neurofilament antigen was observed in 9/21 cases. Staining for one or more neuroendocrine markers in formalin-fixed tissue (bombesin, 7/20; chromogranin, 11/21; synaptophysin, 6/21) was weak and focal but present in 17/21 cases. In 3 cases, sections of unfixed, snap-frozen tumor were compared with formalin-fixed tissue, and these showed strong, diffuse staining for multiple neuroendocrine antigens. Immunostaining for peptide hormones was not observed, with the exception of weak, focal staining for insulin (1 case), calcitonin (1 case) and somatostatin (2 cases). In 13 cases DNA indices and S-phase fractions (SPF) were determined by flow cytometry on nuclear suspensions from paraffin blocks. DNA histograms in 12 of 13 cases had normal range DNA content (diploid) and elevated S-phase fractions (mean 15%, range 8 to 22%). Mean SPF was not significantly different in the group of patients who developed recurrent and/or metastatic disease (15.6%, N = 10) compared with patients without recurrence (15.8%, N = 10).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cutaneous neuroendocrine (Merkel cell) carcinoma: an immunophenotypic, clinicopathologic, and flow cytometric study. 266 40


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