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)

We have studied immunolocalization of all steroidogenic enzyme involved in sex steroids biosynthesis, P-450 side chain cleavage (P-450scc), 3 beta hydroxy steroid dehydrogenase (3 beta-HSD), P-450 17 alpha hydroxylase (P-450(17 alpha)) and P-450 aromatase (P-450arom) and that of vimentin and cytokeratin in 14 cases of testicular sex cord-stromal tumours (6 Leydig cell tumours, 5 Sertoli cell tumours, 2 fibromas and 1 granulosa cell tumour) as well as 4 cases of hyperplasia (2 Leydig and 2 Sertoli). Leydig cell tumour expressed all four steroidogenic enzymes examined, indicating that this tumour can synthesize oestrogen from cholesterol. In 2 cases of Sertoli cell tumour, the tumour cells with clear cytoplasm and without Reinke's crystals expressed P-450ssc, 3 beta-HSD and P-450(17 alpha), suggesting the capability of androgen production in these tumour cells. Fibromas and granulosa cell tumour were negative for the enzymes examined. In immunohistochemistry of intermediate filaments, Leydig cell tumours demonstrated only vimentin. Sertoli cells in hyperplasia and non-neoplastic testis expressed only vimentin but Sertoli cell tumours expressed both cytokeratin and vimentin. Cytokeratin immunoreactivity was correlated with morphological epithelial differentiation in Sertoli cell tumour. These findings in testicular Sertoli cell tumour are considered to represent the multiple differentiation capacity of this neoplasm. Immunohistochemical study of steroidogenic enzymes and intermediate filaments provided new insight into neoplastic steroidogenesis and the differentiation capacity of testicular sex cord-stromal neoplasms.
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PMID:Testicular sex cord-stromal lesions: immunohistochemical analysis of cytokeratin, vimentin and steroidogenic enzymes. 138 Nov 30

Teleocidin, a tumor promoter, inhibited the proliferation, enhanced cytokeratin assembly and increased the type III procollagen production of PLC/PRF/5 hepatoma cells. Teleocidin transiently increased the levels of c-fos and p53 mRNAs measured by reverse transcription and polymerase chain reaction. This was followed by a reduction of c-myc mRNA and an increase of cytokeratin mRNA. The level of p120 mRNA was not remarkably altered. Sequential alterations of the expression of c-fos, p53, c-myc and cytokeratin genes induced by teleocidin may be responsible for the morphological and functional changes of hepatoma cells induced by this tumor promoter.
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PMID:Co-ordinate expression of c-fos, p53 and cytokeratin genes during the alteration of growth of human hepatoma cells. mRNA levels measured by reverse transcription and polymerase chain reaction. 138 34

Thirty-five paraffin-embedded medulloblastomas (19 from children and 16 from adults; 24 classic medulloblastomas, 10 desmoplastic medulloblastomas, 1 tumor with neuronal differentiation) were examined for reactions with antibodies against glial fibrillary acidic protein (GFAP), cytokeratins KL1 and MNF116, desmin, and vimentin. Only the tumor from the youngest patient, a 152-day-old boy, showed a positive immunoreaction for cytokeratins. Because of this age-related expression of cytokeratins in medulloblastomas primarily in very young children, cytokeratin positivity was interpreted as a sign of tumor immaturity. Five medulloblastomas showed scattered GFAP-positive reactive astrocytes and/or other positive, probably neoplastic, cells. Only two tumors showed GFAP immunoreactivity in unequivocally neoplastic cells. Of six tumors that reacted with vimentin, three showed strong reactivity throughout, one being the tumor from the 152-day-old boy. The remaining three demonstrated nests of vimentin-positive cells with weak or intense somatic immunoreactivity for vimentin. None of the 35 cases showed positivity for desmin; indicating that mesenchymal differentiation is restricted to the rare so-called medullomyoblastomas.
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PMID:Age-related immunoreactivity pattern in medulloblastoma. 138 52

Epithelial cell intermediate filaments, or cytokeratins, are excellent markers for cell differentiation. During embryogenesis, cytokeratins specific of a stage of differentiation step always become detectable before corresponding morphologic changes: for instance, cytokeratins 5 and 14 are found around the eight week, shortly before stratification of the epithelium occurs, and cytokeratins 1 and 10 are produced before morphologic evidence of keratinization becomes detectable. Among potential diagnostic applications, analysis of cytokeratin patterns of epidermal cells desquamated in the amniotic fluid may provide earlier and less invasive diagnosis than fetoscopic biopsies. Similarly, a review of cytokeratins expressed in a variety of epithelial diseases (involving the epidermis, digestive tract, respiratory tract, urogenital tract, or breast) demonstrated persistence of the original tissue pattern in some instances (this was the case for the majority of simple epithelia) but not in others (complex epithelia). This suggests that cytokeratins may prove valuable as markers for specific tumor stages or types and may provide earlier information than morphologic studies.
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PMID:[Expression of cytokeratins during embryogenesis and in pathologic epithelia]. 138 16

Mesothelioma is a neoplasm that occurs infrequently in childhood; only an estimated 2-5% of all cases present in the first two decades of life. The diagnosis may be perplexing because of its rarity and its pathologic similarities to other papillary or spindle cell neoplasms in the pediatric age group. We have studied eight cases of mesothelial or submesothelial-derived neoplasms of pleural (four cases) and peritoneal (four cases) origin in patients 4 to 17 years of age at diagnosis. Microscopically, six were epithelial, with papillary, tubuloglandular, and solid patterns. Two tumors were predominantly fibrous appearing, one a localized pleural fibroma and the other a diffuse pleural sarcomatoid mesothelioma. All of the tumors were immunoreactive for vimentin, and all except the pleural fibroma stained for either cytokeratin, epithelial membrane antigen, or both. None reacted with antibodies to carcinoembryonic antigen, placental alkaline phosphatase, or Leu-M1. At last follow-up, three patients were dead of tumor, three were alive and well, and two had been recently diagnosed and were undergoing treatment. These results indicate that the immunohistochemical profile delineated for mesothelioma in adults is equally applicable to mesothelial neoplasms in younger patients and is useful in establishing a diagnosis. The prognosis for malignant mesothelioma in childhood appears to be as unfavorable as the adult counterpart, with the possible exceptions of certain clinicopathologic subtypes.
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PMID:Mesothelial and related neoplasms in children and adolescents: a clinicopathologic and immunohistochemical analysis of eight cases. 138 16

Cytogenetic studies of pediatric tumors have revealed a number of reproducible karyotypic abnormalities, including del(p13) found in aniridia-Wilms' tumor association, t(8;14) in Burkitt's lymphoma, and t(11;22) in Ewing's sarcoma. To date, no consistent cytogenetic abnormality has been reported in association with hepatoblastoma. We report the case of a 7-month-old male infant with the undifferentiated small cell variant of hepatoblastoma. Immunohistochemistry revealed reactivity with antibodies to cytokeratin and vimentin throughout the tumor. Alpha-fetoprotein, neuron-specific enolase, and S100 stains were negative. Chromosomal analysis of metaphase cells from a culture of tumor tissue revealed a translocation of most of the long arm of chromosome 22 to the distal long arm of chromosome 10.
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PMID:Undifferentiated small cell hepatoblastoma with a unique chromosomal translocation: a case report. 138 17

The clinical and morphological findings of 53 chondroblastomas in the files of the Bone Tumour Registry of Westphalia are presented. The mean age of all patients was 19.2 years. The male-to-female ratio was 1.5:1. Forty-two of the tumours (79.8%) were located in the long tubular bones and short tubular bones of the hands and were closely related to the growth plate. Six cases (11.3%) were found in the flat bones, 4 cases (7.5%) in the tarsal bones and 1 case (1.9%) in the craniofacial bones. The characteristic radiological feature of 44 investigated lesions was a mostly eccentric radiolucency with a geographic pattern of bone destruction and matrix calcifications. Periosteal reaction was evident in 9% of the cases. Most tumours demonstrate the typical morphological features of chondroblastoma, but 3 cases resembled a giant cell tumour. In 2 cases a haemangiopericytoma-like growth pattern was observed. Nine of the tumours had an aneurysmal bone cyst-like component. Vascular invasion was seen in 1 case. Immunohistochemically most cells in 30 of the cases and fetal chondroblasts in 3 cases were strongly positive with vimentin and S-100 protein. Collagen type II was positive in the chondroid matrix of the tumours and in fetal cartilage tissue; collagen type VI was present focally around individual tumour cells and was always seen in the chondroid matrix of the lesions and in fetal cartilage. These findings support the cartilaginous nature of these tumours. In paraffin sections, 46.6% of the cases revealed a distinct positive reaction of some tumour cells with the monoclonal cytokeratin antibody KL1 (molecular weight 55-57 kDa). Only 4 of them demonstrated a coexpression with the other monoclonal cytokeratin antibody CK (clone MNF 116, molecular weight 45-56.5 kDa). In paraffin sections all fetal chondroblasts were negative with both cytokeratin antibodies. Frozen sections of 3 tumours showed a strong positive reaction with both cytokeratin antibodies in many chondroblasts, indicating an "aberrant" cytokeratin expression. Osteoclast-like giant cells stained positive with leucocyte-common antigen (LCA) and with the macrophage-associated antibody KP1, but were negative with the other macrophage-associated antibody MAC 387. Recurrence rate was 10.7%. The clinical course of all tumours was benign.
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PMID:Chondroblastoma of bone. A clinical, radiological, light and immunohistochemical study. 138 28

Adult granulosa cell tumors (AGCTs) are classified as sex cord-stromal tumors of the ovary. However, they may be confused with other primary ovarian neoplasms. Intermediate filaments, specifically vimentin and cytokeratins, have been identified in AGCTs by immunohistochemistry performed on frozen and formalin-fixed, paraffin-embedded tissue and two-dimensional electrophoresis. Recently, however, immunohistochemical demonstration of cytokeratin has been used as supporting evidence of epithelial rather than sex cord-stromal differentiation in ovarian neoplasia. To investigate further intermediate filamentous proteins in AGCTs, 25 such tumors were studied by immunohistochemistry in formalin-fixed, paraffin-embedded sections. Cytoplasmic staining was observed, frequently in a distinct punctate, paranuclear pattern, in 14 of 25, 14 of 25, and seven of 17 tumors using monoclonal antibodies AE1/AE3, CAM 5.2, and 35BH11, respectively, which share the ability to detect low molecular weight cytokeratins. Staining for cytokeratin was not seen in any of the 17 tumors studied using the antibody 34BE12. Twenty-three of 25 tumors showed strong positivity for vimentin, characteristically seen as globoid paranuclear staining. Nine of 25 tumors contained desmin, which was restricted to the intermixed spindle cell, cortical type stromal component of the tumors. These patterns of immunoreactivity for intermediate filaments, particularly cytokeratins, are different than in common epithelial tumors of the ovary and may be useful in the differential diagnosis of ovarian neoplasia. Moreover, the immunohistochemical detection of cytokeratins should not be used as a criterion for excluding AGCT from the differential diagnosis of an ovarian neoplasm.
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PMID:Intermediate filamentous proteins in adult granulosa cell tumors. An immunohistochemical study of 25 cases. 138 70

We report an unusual large, multicystic, posterior fossa neuroepithelial neoplasm involving the cerebellum, brain-stem, and quadrigeminal cistern of a 9-month-old girl. The neoplasm consisted of variably sized, sharply demarcated nests of small cells with a high nuclear-cytoplasmic ratio and moderately basophilic nuclei, embedded in a desmoplastic, immature-appearing, mesenchymal stroma. The nests contained mitoses but none were seen in the stroma. Glial fibrillary acidic protein (GFAP), neurofilament protein, synaptophysin, and cytokeratin (AE-1) were expressed in the nests. Mesenchymal cells were negative for neural markers but positive for vimentin and desmin. The neoplasm was interpreted as a mixed mesenchymal and primitive neuroectodermal tumor (PNET) with histologic features reminiscent of a recently described intraabdominal desmoplastic small cell tumor. The tumor responded poorly to chemotherapy and a second operation was performed 1 year later. The second specimen bore no resemblance to the original and consisted of epithelial-like nests and clusters of neoplastic cells frequently interrupted by sinusoidal vessels. Tumor cells had medium-sized vesicular nuclei with small nucleoli, and a granular cytoplasm. Occasional less cellular islands of neuropil-like tissue contained larger cells having eccentric, vesicular nuclei with prominent nucleoli and abundant pink cytoplasm. Mitoses were not conspicuous. Many cells expressed synaptophysin, neurofilament protein, and GFAP. Neurofilament protein was strongly positive in the larger, neuron-like cells and synaptophysin stained the neuropil-like areas strongly but was less prominent in the neuronal perikarya. Unexpectedly, the neuropil-like areas expressed epithelial membrane antigen, whereas the neuronal cells were negative for chromogranin A. The peculiar histologic picture, combination of phenotypic markers, and remarkable biologic behavior of this unusual tumor defies classification according to existing nomenclature and exemplifies the broad range of phenotypes expressed by primitive neuro-epithelial neoplasms.
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PMID:Desmoplastic primitive neuroectodermal tumor with divergent differentiation. Broadening the spectrum of desmoplastic infantile neuroepithelial tumors. 138 73

Reported is a case of an embryonal form of extraskeletal myxoid chondrosarcoma. The tumor cells contained PAS-positive, eccentrically located intracytoplasmatic, hyaline-like globules. These globules seemed to be a hallmark of this tumor, and they reacted strongly with cytokeratin and S-100 protein antibodies. The tumor was negative in reactions with desmin and GFAP antibody.
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PMID:Embryonal form of extraskeletal myxoid chondrosarcoma with intermediate filament positive hyaline-like globules. 138 92


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