Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monoclonal antibodies (mAbs) recognizing the disialoganglioside II3(NeuAc)2GgOse3Cer (GD2) were produced by immunizing mice with the GD2-expressing neuroblastoma cell line LAN-1 and a prefusion boost with purified GD2 coupled to Salmonella minnesota. Two IgM mAbs were isolated which demonstrated high levels of reactivity (binding ratios in excess of 100) with GD2 by solid-phase radioimmunoassay and positivity in high-performance thin-layer chromatography (HPTLC) immunostain; only one (DMAb-20) was subsequently shown by analysis with a panel of defined ganglioside species to be specific for the minimum epitope of GD2 GalNAc beta 1-4(NeuAc alpha 2-8-NeuAc alpha 2-3)Gal-, DMAb-20 was used to evaluate the expression of GD2 by malignant glioma and medulloblastoma cell lines using cell surface radioimmunoassay. indirect membrane immunofluorescence. HPTLC immunostain, and densitometric analysis of extracted gangliosides from selected cell lines. Sixteen of 20 (80%) malignant glioma and 5 of 5 medulloblastoma cell lines reacted with DMAb-20; in agreement with previous studies, 5 of 5 neuroblastoma and 2 of 3 melanoma cell lines also reacted with DMAb-20, GD2 was proportionally increased in the glioma and medulloblastoma cell lines relative to levels in normal brain, as determined by densitometric analysis. In a phenotypic survey of malignant glioma biopsies, tumor cells in 24 of 30 (80%) cases stained positively with DMAb-20. Reactive astrocytes, both within the adjacent to tumors, were frequently intensely stained. Among the morphological variants of glioblastoma examined, the most intense staining with DMAb-20 was observed in neoplastic gemistocytes, with the weakest or absent staining in small cell glioblastomas. As GD2 is a commonly expressed surface antigen of gliomas and medulloblastomas, expression of which is retained in tissue culture. DMAb-20 will be useful in determining the functional role of GD2 in cell-cell interaction, adhesion, and invasion, and in defining altered growth control mechanisms of central nervous system neoplasms in in vitro models.
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PMID:Disialoganglioside GD2 in human neuroectodermal tumor cell lines and gliomas. 165 6

The MR examinations in 25 patients with intramedullary tumors were analyzed. Seven patients were diagnosed with astrocytoma, 6 ependymoma, 2 unspecified glioma, 3 medulloblastoma, 2 metastasis, one neurinoma, and one teratoma. In 3 patients the diagnosis was uncertain. The tumors frequently involved a large portion of the cord and were often accompanied by intratumor necrosis, cystic degeneration, and edema, which was well demonstrated on MR. Gd-DTPA was used in 6 patients and was helpful in separating solid tumor components from cysts and edema. It was difficult to separate different kind of tumors based on morphologic and signal characteristics on MR. Some prominent features could, however, be distinguished. Complete cystic degeneration was more common in astrocytomas than in other tumors, and ependymomas frequently had a heterogeneous signal pattern on both T1- and T2-weighted sequences. The single teratoma had a characteristic content of fat and calcification, and the melanoma had a signal pattern consistent with blood. CSF pathway spread in cases of medulloblastoma was demonstrated by ill-defined contour of the cord and CSF or tumor nodules on the surface of cord and nerve roots.
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PMID:MR imaging of spinal intramedullary tumors. 166 Feb 97

In a group of four human tumor cell lines comprising one melanoma, one glioma, one teratocarcinoma and one neuroblastoma, the expression of the intercellular adhesion molecule-1 (ICAM-1) was found to be significantly increased following treatment with 10 microM of all-trans retinoic acid. In the melanoma and glioma cell lines HS 294T and HS 683, greater than 90% of the cells reacted with the anti-ICAM-1 monoclonal antibody (mAb) CL203.4 in the absence of treatment. Retinoic acid increased the cell surface expression of the molecule by 2-fold. In the teratocarcinoma and neuroblastoma cell lines, TERA-2 and SK-N-SH, the constitutive expression of ICAM-1 was weak, the percentage of cells stained above the background being less than 25%. Retinoic acid induced ICAM-1 expression in greater than 80% of the cells and increased the levels of expression by 2.5 to 3-fold. Immunoprecipitation studies in biosynthetically labeled cells as well as RNase protection analysis confirmed that retinoic acid treatment increased the amount of ICAM-1 at both the protein and mRNA level. The induction or stimulation occurred within 24 h, was maximal after 4 days and reversible.
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PMID:Regulation by retinoic acid of ICAM-1 expression on human tumor cell lines. 168 Mar 99

The possibility for new interferon therapy was investigated using the effect of endogenous human interferon-beta (HuIFN-beta) on various culture cell lines. Cell lines were exposed to superinduction agents (poly I: poly C, cycloheximide, and actinomycin D) and the production of endogenous interferon analyzed. Quantitative determination of HuIFN-beta and messenger ribonucleic acid (mRNA) showed HuIFN-beta was induced in all of five glioma cell lines, one of two melanoma cell lines, and all of three lung carcinoma cell lines as well as fibroblasts. Northern blot analysis showed HuIFN-beta mRNA induced in glioma cells was identical to that from fibroblasts. Endogenous HuIFN-beta induced from glioma cells had a cytostatic or cytocidal effect against various human glioma cell lines, even those resistant to fibroblast-derived HuIFN-beta. These results show it may be possible to use the induction of excess endogenous cytotoxic HuIFN-beta in human glioma tissue itself.
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PMID:Superinduction of cytotoxic interferon-beta in glioma cells. 172 75

Interferons are currently the most widely used biological response modifiers. They are of high clinical value in haematological malignancies (chronic myelogenous leukaemia, multiple myeloma, non-Hodgkin lymphoma), in solid tumours (malignant melanoma, hypernephroma, pancreas neoplasms, carcinoid tumours, Kaposi's sarcoma, glioma, in ovarium, cervix and bladder carcinoma, and in basalioma) and in infectious diseases (chronic hepatitis B, chronic non-A/non-B hepatitis, chronic delta hepatitis, AIDS, Papova virus and Rhinovirus infections, leishmaniasis, leprosy) and some other conditions. Although the mechanism of action of interferons has not been explained in every detail these agents are promising therapeutic means in a number of diseases.
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PMID:Role of interferon in clinical practice. 172 32

Gangliosides shed by tumors enhance tumor formation, possibly by suppressing host antitumor immune function, and gangliosides purified from animal tissues and cultured cells inhibit human cellular immune function in vitro. Determination of immunosuppressive activity of highly purified gangliosides, to uncover structure-activity relationships, is therefore important. Here we have studied a series of gangliosides obtained from human tissue and determined their effects on human natural killer (NK) activity. Total gangliosides from human brain tissue were moderately inhibitory; 100 nmol/ml reduced NK activity of human nonadherent PBMC by 43%. The influence of carbohydrate structure upon inhibitory activity was determined by study of eight highly (HPLC) purified individual gangliosides. Of these, we unexpectedly found that the two minor brain gangliosides with the simplest carbohydrate structures, GM2 and GM3, were very active inhibitors (75 and 47%, respectively, at 50 nmol/ml). In contrast, the structurally more complex major species, GM1, GD1a, GD1b, GT1b, and two other minor gangliosides, GD2 and GD3, were inactive. Reduced effector-target binding in a single-cell binding assay by GM2 but not GM3 suggests different mechanisms of inhibition by these two active gangliosides. Since GM2 and GM3 are present in high concentrations in, and are shed by, several common human tumors (e.g., neuroblastoma, melanoma, and glioma), their ability to inhibit NK cytotoxicity supports the hypothesis of a role of shed tumor gangliosides in the enhancement of tumor formation.
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PMID:Immunosuppression by human gangliosides. II. Carbohydrate structure and inhibition of human NK activity. 172 65

Iododeoxyuridine is a halogenated pyrimidine and non-hypoxic cell radiosensitizer currently being used in clinical trials. The amount of radiosensitization by IdUrd is related to the amount of incorporation of the drug into a cell's DNA. These experiments were carried out in three human tumor cell lines (lung, glioma, and melanoma) in monolayer culture exposed to concentrations of IdUrd from 0.1-10 microM for one and three cell cycles before irradiation to determine incorporation and sensitization as a function of drug exposure. Except for the lung cell line, which required greater than 1 microM IdUrd, these cells demonstrate radiosensitization when exposed to 0.1 microM or greater of IdUrd. Maximum sensitization occurred at 10 microM IdUrd for all the cell lines at three cell cycles. The percent thymidine replacement by IdUrd increased with increasing concentrations, but was cell line dependent. Maximum percent replacement occurred at 10 microM at three cell cycles for all the cell lines: lung = 22.4%, glioma = 32.0%, and melanoma = 39.1%. The relationships between percent thymidine replacement and sensitization are not identical across these human tumor cell lines. If IdUrd is going to be a successful radiosensitizer in clinical trials, sustained plasma levels of 10 microM or greater for at least three cell cycles should be achieved during irradiation. This may be best accomplished with repeated short exposures to IdUrd (three cell cycles or approximately 4 days in these cell lines) every 1-2 weeks during radiation. Measurements of thymidine replacement in a tumor biopsy should be attempted prior to radiation to develop a predictive assay for radiosensitization.
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PMID:Iododeoxyuridine incorporation and radiosensitization in three human tumor cell lines. 173 85

beta-Sitosterol (SI-0), beta-sitosterol glucoside (SI-1), dioscin (SI-2), methyl protoprosapogenin A of dioscin (SI-3), methyl protodioscin (SI-4) and protodioscin (SI-5) were isolated and characterized from the whole plant of Solanum indicum L. (Solanaceae). Except for beta-sitosterol, these compounds have not been previously isolated from Solanum indicum L. Both CHCl3 soluble (SI-IV) and insoluble (SI-V) fractions of the ethanolic extract (SI-I) showed cytotoxicity on seven cancer cell lines: Colo-205 (colon), KB (nasopharynx), HeLa (uterine cervix), HA22T (hepatoma), Hep-2 (laryngeal epidermoid), GBM8401/TSGH (glioma) and H1477 (melanoma). The purified constituents, SI-2 and SI-4 showed more potent effects by DEA and MTT assay. SI-2,3,4 and 5 also demonstrated cytotoxicity on cultured C6 glioma cells by PRE assay, ans SI-3,4 and 5 showed a tumor inhibitory effect in vivo in C6 glioma cells. In addition, SI-2 had an inhibitory effect on the DNA synthesis of C6 glioma cells at 10 micrograms/ml.
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PMID:Experimental antitumor agents from Solanum indicum L. 176 63

Xenogeneic immunization of freshly-prepared human glioma extracts into goats has yielded a polyclonal antiserum, which after multiple absorptions specifically identifies antigenic entities only in glioma extracts, and not in appropriate controls, both by radioimmunoassays (RIAs) and Western immunoblots. The results from the absorbed polyclonal antiserum have been confirmed by the successful generation of six stable murine monoclonal antibodies (MAbs) which recognize a subset of the same antigens with high specificity on immunoblots and with no apparent cross-reactivities by RIA to normal brain, serum, liver, muscle, kidney, spleen, or melanoma tissues. Moreover, the tested murine MAbs (B12C4) reveal a striking and abundant glial filament protein, possibly related to glial fibrillary acidic protein (GFAP) or other intermediate filament proteins, by frozen-section immunofluorescence. This is seen only in gliomas and is absent, or dramatically reduced, in normal human cortex. Use of potent immortalizing strain (FF41) of Epstein-Barr virus (EBV) to establish antibody-secreting human lymphoblastoid lines, and the generation of mouse-human chimeric fusions, have yielded lines possessing variable supernatant human antibody secretion. Radioimmunoassays using culture supernatants, and sera from glioma patients and an normal individual, have demonstrated surprisingly similar reactivity profiles, even after a sensitive sandwich RIA employing the B6C6 murine MAb. These results suggest that, although human glioma-associated antigens, including possibly the up-regulation of GFAP expression, clearly exist, there seems to be a muted humoral response as evidenced by a paucity of tumor-specific B-cells. This may be due to antigenic shielding by the blood-brain barrier, or due to a form of immunological compromise in patients harboring these malignancies.
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PMID:Paucity of humoral response in patients to glioma-associated antigen(s): antigen localization by immunofluorescence. 180 70

Human glioma-associated markers can be exploited for the development of new diagnostic strategies and treatment modalities for these malignancies. A goat antiserum was first raised against human anaplastic astrocytoma (AC or AA) and glioblastoma multiforme (GB or GBM) extracts. Extensive sequential absorptions with normal brain tissue, normal serum, and human serum albumin (HSA) gave an antibody fraction specific for glioma. Balb/c mice were subsequently immunized with these glioma extracts. B-cell hybridomas from these mice were then cloned and subcloned by limiting dilution, yielding six monoclonal antibodies (MAbs) that were entirely specific for tumor tissues, and did not react with normal human serum or with normal human brain, liver, kidney, spleen, or muscle. Moreover, the murine MAbs did not cross-react with certain other human tumors, including melanoma. The fully absorbed antiserum and the murine MAbs both identify a polypeptide pattern possibly related to human glial fibrillary acidic protein (GFAP) or other intermediate filament proteins on immunoblots. These immunological reagents could serve as powerful tools for the diagnosis and possibly therapy of these uniformly fatal tumors.
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PMID:Preparation and characterization of antisera and of murine monoclonal antibodies to human glioma-associated antigen(s). 180 72


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