Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have recently identified and cloned the gene for a cytosolic polypeptide, designated oncoprotein 18 (Op18), which is expressed in acute lymphocytic leukemia and some solid tumors including neuroblastoma. Op18 is phosphorylated upon treatment of lymphoid cells with phorbol myristate acetate. We have proposed that unphosphorylated Op18 plays a role in cellular proliferation, and that its phosphorylated forms, namely Op18a and Op18b, are associated with diminished cell proliferation. In this study, we report that in neuroblastoma tumors, the phosphorylation of Op18 was substantially diminished with increasing N-myc gene copy number. Treatment of the neuroblastoma cell line SMS-KCNR, which contains 75 copies of the N-myc gene, with retinoic acid for ten days resulted in an increase in Op18 phosphorylation. Our findings provide evidence for distinct patterns of Op18 phosphorylation in neuroblastoma tumors with and without N-myc gene amplification.
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PMID:N-myc gene amplification in neuroblastoma is associated with altered phosphorylation of a proliferation related polypeptide (Op18). 226 30

The neural cell adhesion molecules L1 and N-CAM have been suggested to interact functionally by formation of a complex between the two molecules (Kadmon, G., A. Kowitz, P. Altevogt, and M. Schachner. 1990. J. Cell Biol. 110:193-208). To determine the molecular mechanisms underlying this functional cooperation, we have studied the contribution of carbohydrates to the association of the two molecules at the cell surface. Aggregation or adhesion between L1- and N-CAM-positive neuroblastoma N2A cells was reduced when the synthesis of complex and/or hybrid glycans was modified by castanospermine. Fab fragments of polyclonal antibodies to L1 inhibited aggregation and adhesion of castanospermine-treated cells almost completely, whereas untreated cells were inhibited by approximately 50%. Fab fragments of polyclonal antibodies to N-CAM did not interfere with the interaction between castanospermine-treated cells, whereas they inhibited aggregation or adhesion of untreated cells by approximately 50%. These findings indicate that cell interactions depending both on L1 and N-CAM ("assisted homophilic" binding) can be reduced to an L1-dominated interaction ("homophilic binding"). Treatment of cells with the carbohydrate synthesis inhibitor swainsonine did not modify cell aggregation in the absence or presence of antibodies compared with untreated cells, indicating that castanospermine-sensitive, but swainsonine-insensitive glycans are involved. To investigate whether the appropriate carbohydrate composition is required for an association of L1 and N-CAM in the surface membrane (cis-interaction) or between L1 on one side and L1 and N-CAM on the other side of interacting partner cells (trans-interaction), an L1-positive lymphoid tumor cell line was coaggregated with and adhered to neuroblastoma cells in the various combinations of castanospermine-treated and untreated cells. The results show that it is the cis-interaction between L1 and N-CAM that depends on the appropriate carbohydrate structures.
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PMID:Functional cooperation between the neural adhesion molecules L1 and N-CAM is carbohydrate dependent. 229 83

BALB/c mice were immunized with tyrosinase, partially purified in two stages from a human melanoma cell line. A hybridoma was obtained which produced monoclonal antibody (MoAb 1C11) reactive with 8/10 melanoma cell lines and 10/10 primary cultures of human melanocytes, neval cells, and melanomas. Immunoreactivity correlated to a certain extent with tyrosinase activity but not with melanin content. No crossreactivity was obtained with neuroblastoma, medulloblastoma, fibroblasts, keratinocytes, lymphoid cells, or murine melanomas. Purification of the antigen directly from cell lysates with a MoAb 1C11 CNBr-Sepharose affinity column gave a green-brown protein of 56 kDa with no detectable tyrosinase activity. This protein was therefore different from 60 kDa active tyrosinase, identified by enzyme activity and Western blotting with a MoAb derived previously (MoAb 5C12). Unlike 5C12, 1C11 reactivity was not destroyed by pretreatment of the antigen with periodate. Immunogold labelling showed that the 1C11-reactive antigen was associated with melanosomes, and there was close correlation between 5C12 and 1C11 reactivity in resistance to trypsin and in staining various melanocytic cell populations. MoAb 1C11 may therefore recognise a polypeptide epitope in a molecule closely linked to melanin biosynthesis.
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PMID:Monoclonal antibody against a melanosomal protein in melanotic and amelanotic human melanoma cells. 247 76

The Ly-6 locus contains multiple genes encoding cell surface proteins, two of which, when cross-linked by antibodies, effect antigen-independent activation of T lymphocytes. In this study, cDNA for Ly-6-encoded antigens have been used as probes to examine RNA from various tissues and transformed cell lines for constitutive levels of Ly-6 RNA expression. Analyses of RNA prepared from several different tissues revealed a high level of expression of Ly-6 RNA in kidney, spleen, heart and thymus, with a more moderate level of expression in liver, brain and lung tissue cells. A survey of various cell lines demonstrated the presence of Ly-6 RNA in many, but not all T lymphocytic cell lines, in L cells, the Meth A fibrosarcoma, in the TCMK kidney cell line, and in the Neuro-2a neuroblastoma. We also evaluated the expression of Ly-6 RNA in cells after treatments with interferons (IFN) and interleukin 1 (IL1). Treatment of lymphoid cells with IFN (alpha/beta and gamma), known to increase cell surface Ly-6 antigen expression in normal T cells, was correlated with increases in Ly-6 RNA levels. Increases in levels of RNA correlated with increases in levels of the Ly-6A/E or Ly-6C antigens. Several T lymphoid cell lines exhibiting Ly-6 RNA inducibility by IFN were similarly inducible with IL1. Kinetic experiments using one such line, (YAC-1), showed that the induction of Ly-6 RNA mediated by IFN-alpha/beta occurred rapidly (within 4 h), while the induction by IL1 required relatively more time (approximately 8 h). Although the actions of IFN-alpha/beta were not blocked by cycloheximide, the presence of this protein synthesis inhibitor significantly attenuated the effects of IL1 and IFN-gamma on Ly-6 RNA transcription. Induction by IFN-gamma as well as IL1 could be blocked completely by co-culture with anti-IFN-gamma, implicating IFN-gamma as a mediator of the induction by IL1.
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PMID:Kinetic analysis of Ly-6 gene induction in a T lymphoma by interferons and interleukin 1, and demonstration of Ly-6 inducibility in diverse cell types. 247 47

1. The major functional role played by phosphorylation of plasma membrane proteins in the biological properties of tumor cells suggests that identification of protein kinases and their substrates will contribute to our understanding of the molecular basis of the malignant process and of the aberrant behavior of tumor cells. 2. The present study has investigated the phosphorylation of surface proteins of human tumor cells. Incubation of plasma membranes isolated from cultured human melanoma cells with [gamma-32P]ATP in the presence of Ca2+ and ethylene-bis-(oxyethylenenitrilo)-tetraacetic acid (EGTA) resulted in specific phosphorylation of serine and threonine residues on a 75kDa protein (pp75). 3. Neither Ca2+ or EGTA alone, nor any other divalent metal ion tested could induce phosphorylation of pp75. 4. The phosphorylation of pp75 was directly dependent upon the presence of non-ionic detergents, and was influenced by length of incubation and concentration ratio of Ca2+ and EGTA. 5. Incubation of isolated plasma membranes with [gamma-32P]ATP in the presence of Ca2+ and EGTA and immunochemical analysis by Western blotting with an anti pp75 xenoantiserum detected the pp75 in human melanoma, neuroblastoma, ovarian carcinoma and lymphoid T cells and fibroblasts but not in B-lymphoid cells, renal carcinoma cells, peripheral blood lymphocytes and splenocytes. 6. These results suggest the presence of a new class of plasma membrane bound protein kinases activated by chelated calcium and differentially expressed in normal and transformed human cells.
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PMID:Specific phosphorylation by calcium-EGTA complex of a 75 kDa human tumor plasma membrane protein (pp75). 250 5

By fusion of mouse NS1 myeloma cells with splenocytes from a BALB/c mouse immunized with human melanoma cells, an IgG1 monoclonal antibody, designated as 140.72, was produced. By the mixed hemadsorption antibody binding assay, 140.72 was shown to react with 17 of 20 melanoma cell lines and with 5 of 14 carcinoma cell lines. This antibody also reacted with 3 of 3 normal melanocyte cultures in much lower titers. It did not react with any of 35 other normal and malignant lines, including neuroblastoma, glioblastoma, sarcoma, teratoma, fibroblast, and lymphoid cell lines. Absorption with fresh melanoma and carcinoma homogenates confirmed the results of direct tests. Fetal reactivity of antibody 140.72 was determined by positive absorption with 10 of 11 tissue homogenates derived from different fetuses of 10-16 weeks' gestation. The reactivity of this antibody was completely removed by absorption with a highly purified preparation of carcinoembryonic antigen (CEA) derived from a colon carcinoma. The antigenic activity was detected in the culture medium of reactive cell lines. Immunoprecipitation analyses of melanoma and carcinoma cells indicated that the antigenic determinant recognized by antibody 140.72 is on a glycoprotein with an apparent molecular weight of 95,000-150,000 common to both serologically reactive cell types. Additionally, a 200,000-molecular-weight glycoprotein corresponding to the CEA molecule was detected only on the reactive carcinoma cells. These data confirmed previous findings obtained with polyclonal anti-CEA antisera for the existence of shared CEA-related antigenic determinants on human carcinomas and melanomas and provided additional molecular characterization of these glycoproteins. Further characterization of the molecules bearing the antigenic determinant recognized by antibody 140.72 should be performed with a view to exploring its potential in the immunodiagnosis and immunotherapy of patients with melanoma.
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PMID:Monoclonal antibody recognizing human melanoma-carcinoma cross-reacting oncofetal antigen epitopically associated with carcinoembryonic antigen. 258 73

Amplification of the N-myc oncogene in human neuroblastoma is associated with increased metastatic ability. We previously found that over-expression of N-myc in rat neuroblastoma tumor cells causes a dramatic reduction in the expression of MHC class I mRNA. We show here that two distinct elements in the promoter render the MHC class I genes susceptible to N-myc-mediated suppression, one of which was identified as the MHC class I gene enhancer. Our data indicate that elevated N-myc expression is associated with reduced binding of a transcription factor that activates this enhancer. As a result, the activity of the MHC class I gene enhancer is greatly diminished. Elevated expression of the N-myc oncogene in human neuroblastomas and murine pre-B lymphoid lines also correlated with reduced factor binding to the MHC class I gene enhancer. Thus, an important effect of N-myc may be to impair the function of certain cellular enhancers by altering the levels of their cognate binding proteins.
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PMID:Suppression of MHC class I gene expression by N-myc through enhancer inactivation. 258 2

Sinonasal neoplasms and neoplasm-like proliferations composed of light microscopically poorly differentiated or undifferentiated, small- to medium-sized cells cause considerable diagnostic confusion. Lesions in this category include lymphoepithelioma (undifferentiated carcinoma), olfactory neuroblastoma, small-cell undifferentiated (oat cell) carcinoma, sinonasal undifferentiated carcinoma, malignant melanoma, pituitary adenoma, lymphoid hyperplasia, malignant lymphoma, plasmacytoma, lymphomatoid granulomatosis, rhabdomyosarcoma, mesenchymal chondrosarcoma, small cell osteosarcoma, Ewing's sarcoma, and synovial sarcoma. Many of these lesions can be definitively diagnosed based on light microscopic features alone, but, in some instances, additional techniques such as immunohistochemistry are of value. The authors review the pertinent clinicopathologic features of the above lesions, with emphasis on light microscopic, immunohistochemical, and ultrastructural features of particular utility in differential diagnosis.
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PMID:"Undifferentiated" neoplasms of the sinonasal region: differential diagnosis based on clinical, light microscopic, immunohistochemical, and ultrastructural features. 269 5

In summary, carcinoma is the most frequent cancer that metastasizes to the skin; lung cancer in men and breast cancer in women. Clinically distinctive patterns of cutaneous metastasis of epithelial origin include alopecia neoplastica, pulsatile nodules, Sister Mary Joseph's nodules, morpheaform, and cellulitis-like lesions. Biopsying these lesions reveals adenocarcinoma, squamous cell carcinoma, or anaplastic carcinoma. The type of histologic pattern seen can be a clue to the organ of origin giving rise to the cutaneous metastasis. Skin that is damaged allows for circulating malignant cells, often of epithelial or leukemic origin, to lodge and proliferate locally (inflammatory oncotaxis). The commonest form of leukemia to affect the skin of elderly males is chronic lymphocytic leukemia. However, when leukemia involves the mucous membranes, acute myeloid leukemia (acute monocytic and acute myelomonocytic leukemia) is the most likely diagnosis. When papules, nodules, or plaques develop on the head, neck, or torso in a middle-aged male accompanied by lymphadenopathy, there must be a high index of suspicion that these lesions are metastatic lymphomatous deposits. Definitive histologic diagnosis on a skin biopsy specimen is difficult. In this situation, it is best to rely on histologic patterns seen in lymphoid tissue along with cellular marker studies. An elderly patient having bone pain, anemia, elevated blood calcium level, and renal failure along with purplish or skin-colored nodules and plaques on the trunk has a good chance of having multiple myeloma. Biopsying these lesions is most certain to reveal atypical plasma cells, and blood immunoelectrophoresis will demonstrate characteristic monoclonal gammopathy. There are two malignancies seen in children under 3 years of age that often times affect the skin in a characteristic fashion. Letterer-Siwe disease, which is distinguished from other histocytic disorders by its cell of origin, the Langerhans cell, clinically shows maculopapular and erosive lesions distributed in a seborrheic pattern. Neuroblastoma derived from cells of the neural crest demonstrates clinically widespread bluish papulonodules. Kaposi's sarcoma, a multifocal vascular malignancy, has a wide spectrum of clinical expression. Those patients who are immunocompromised secondary to concomitant disease or immunosuppressive therapy are more susceptible to a disseminated fulminant course accompanied by opportunistic infection. In conclusion, although specific signs of internal malignancy are less common than nonspecific ones, they are just as important; if the clinician managing the cancer patient is familiar with these clues to internal disease, proper patient management will ensue.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Specific cutaneous manifestations of internal malignancy. 307 47

A panel of antibodies recognising lymphoid and epithelial antigens in formalin fixed, paraffin embedded sections was applied to a series of 54 bone marrow trephines decalcified by formic or edetic acids. Normal trephines and cases infiltrated by myeloid, lymphoid, and epithelial tumours were included. Patterns of reactivity were distinct and allowed the different diseases to be distinguished. All lymphoid tumours expressed leucocyte common antigen, with B cell tumours staining with MB1 and MB2, and T cell tumours staining with MT1 and UCHL1. T cell acute lymphoblastic leukaemia (ALL)/lymphoblastic lymphoma all stained with MT1, but some were negative with UCHL1. B cell ALL/lymphoblastic lymphoma also stained with MT1, but could be distinguished by its reactivity with MB1 and MB2. Reed-Sternberg cells did not stain with any reagent. Normal and neoplastic myeloid cells stained with MT1. Carcinomas stained with CAM 5.2 but were negative for lymphoid markers except MB2 staining in some cases. A case of neuroblastoma could be distinguished from ALL/lymphoblastic lymphoma by its lack of reactivity with all antileucocyte antibodies and its staining with antineurone specific enolase. Although not ideal, if used together, this panel of reagents may usefully be applied to routinely fixed and processed, decalcified bone marrow trephines.
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PMID:Demonstration of lymphoid antigens in decalcified bone marrow trephines. 330 63


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