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)

A panel of monoclonal antibodies, designated HMB 18, 45, and 50, have been isolated that are highly specific for malignant melanoma. When tested on fixed, paraffin-embedded tissue sections, they reacted with 97 percent of melanomas tested (58 of 60), including pigmented, unpigmented, primary, and metastatic melanoma. The specificity in differentiating melanomas from other malignant tumors, including 112 carcinomas, 35 lymphomas, and 39 sarcomas, was 100 percent. Normal melanocytes were unreactive, although some benign melanocytic lesions were recognized. Using immunoprecipitation and SDS-PAGE analysis of 35S-methionine-labeled melanoma cells in tissue culture, a previously undescribed protein of approximately 10 kd was recognized by all three antibodies. HMB 50 also precipitated two high molecular weight proteins of 97 kd and 110 kd from the conditioned medium of melanoma cells. These monoclonal antibodies are the most sensitive and specific antibodies generated against human melanoma to date. Their clinical application in diagnostic surgical pathology and potential use in immunotherapy are discussed.
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PMID:Unique proteins defined by monoclonal antibodies specific for human melanoma. Some potential clinical applications. 376 67

We have isolated a cDNA clone corresponding to a substantial portion of the human tissue-type plasminogen activator (t-PA) protein. It encodes almost all of the protein B chain and part of the 3' untranslated region. We have used this clone to screen bacteriophage lambda and cosmid libraries of human genomic DNA. Several related genomic clones were isolated. One of these, a cosmid clone, carried approx. 40 kb of human DNA. Mapping experiments indicate that the region containing the protein-coding exons is approx. 20 kb in length. The cosmid, containing the t-PA gene and the aminoglycosyl-3'-phosphotransferase dominant-selection marker, was introduced into mouse L cells. Approximately half of the transformants were shown to produce human t-PA. We demonstrated that the fibrinolytic t-PA activity could be specifically quenched by anti-t-PA antibody and that the recombinant t-PA was of similar size (by SDS-polyacrylamide gel electrophoresis) to the t-PA produced by the human Bowes melanoma cell line. Our results suggest that the cosmid clone carries the whole t-PA coding region together with the regulatory elements necessary for its expression.
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PMID:Isolation of a human tissue-type plasminogen-activator genomic DNA clone and its expression in mouse L cells. 383 98

A monoclonal antibody (MAb NKI/C-3) produced against a purified membrane preparation of human melanoma cells reacts preferentially with sections of formaldehyde-fixed and paraffin-embedded tissues of melanoma, nevocellular nevi, carcinoids and medullary carcinomas of the thyroid. NKI/C-3 did not react with basal-cell carcinoma, brain tissue or brain tumors, and in only 14/196 other tumors was a clear cross-reactivity observed, e.g. with prostate carcinomas and a minority of primary breast, ovarian, lung and clear-cell carcinomas. This antibody was used in an immuno-electron microscopic study for the cellular localization of the antigen. The antigen was dispersed in the cytoplasm of melanoma cells, and more concentrated inside vacuoles and sometimes also on the melanosomes. Occasionally, the antigen was seen on the cell surface. The nature of the antigen was determined in an enzyme immunoassay (EIA). It was found that the antigen is a glycoprotein with a disulfide-dependent configuration that is essential for recognition by the MAb. The antigen was distributed heterogeneously during gel filtration as well as during SDS-polyacrylamide gel electrophoresis in the region of 25-110 kd proteins. A purified antigen preparation that was obtained after affinity chromatography on a column of MAb NKI/C-3 linked to Sepharose 4B contained a carbohydrate:protein ratio of 1:3.5.
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PMID:Biochemical characterization and cellular localization of a formalin-resistant melanoma-associated antigen reacting with monoclonal antibody NKI/C-3. 388 81

A melanoma-associated oncofetal antigen, gp87 (a p97-like molecule), defined by the monoclonal antibody (MoAb) 140.240 has been purified to homogeneity from the spent medium of cultured melanoma cells by a two-step immunoadsorbent procedure. The first immunoadsorbent step using glutaraldehyde-insolubilized MoAb 140.240 (ascites fluid) resulted in a 13-fold enrichment with 93% recovery in the bound material. In the second immunoadsorbent step constructed by the purified IgG2a of MoAb 140.240 (culture fluid) coupled to CNBr-activated Sepharose 4B the bound material from the first step was further purified resulting in a 330-fold purification with 90% recovery. SDS-polyacrylamide gel electrophoretic analysis of the final purified material revealed a single band migrating as a polypeptide with an approximate molecular weight of 87 Kd, consistent with the size of the molecule immunoprecipitated by MoAb 140.240 from lysates of radiolabelled melanoma cells. Preliminary amino acid analysis indicates a particularly high proportion of phenylalanine in gp87. We have also compared gp87 with two well defined antigens, HLA-A,B,C (integral membrane protein) and "94K" melanoma/carcinoma-associated antigen (peripheral membrane protein) with respect to antigen extractability from melanoma cells using phosphate-buffered saline, 0.1 M urea, 3 M NaCl, or nonionic detergent (NP-40). The results showed that whereas 94K antigen was extractable by each of the four different solutions, gp87, similar to HLA-A,B,C antigens, could only be extracted with NP-40, strongly suggesting that gp87 is an integral melanoma cell component.
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PMID:Immunopurification, characterization, and nature of membrane association of human melanoma-associated oncofetal antigen gp87 defined by monoclonal antibody 140.240. 388 78

The purification of two isoenzymes of tyrosinase has been carried out in Harding-Passey mouse melanoma. One is found in the cytosol and the other one bound to melanosomes. Both migrate as single bands on sodium dodecyl sulphate/polyacrylamide gels, having an apparent Mr of 58 000. Solubilized particulate tyrosinase showed an aggregation equilibrium involving a monomer, tetramer, octamer and a high-Mr micellar form with Brij 35, the solubilizing agent. H.p.l.c. studies indicated a interconversion between those species, the monomer contribution increasing with the sample dilution. The tetramer and the octamer probably represent the predominant forms in vivo. Soluble tyrosinase showed a simpler aggregation equilibrium, involving two forms, monomer and tetramer, with the same interconversion pattern. Fluorescence studies suggested that tryptophan residues were exposed to the aqueous environment when tyrosinase was dissociated by dilution. Tyrosinase shows a tendency to aggregate, at low protein concentration, and a resistance to dissociation by urea or SDS so remarkable that gel-permeation chromatography in 4M-urea does not affect the equilibrium, and the band obtained on SDS/polyacrylamide-gel electrophoresis is a dimer.
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PMID:Aggregation equilibria of tyrosinase of Harding-Passey mouse melanoma. 392 35

While developing monoclonal antibodies (MoAb) to colorectal carcinoma (CRC) cells, we noted that one MoAb, termed CJA3, down-regulated natural cell-mediated cytotoxicity (NCMC) against CRC cell lines SW480 and SW620. The MoAb CJA3 was developed by immunizing a BALB/c mouse with fresh human colorectal adenocarcinoma cells. The antigen recognized by the MoAb CJA3 was expressed on several solid tumor cell lines and on one of the six lymphoreticular cell lines tested, but was not detected on normal peripheral blood lymphocytes (PBL). SDS-PAGE analysis of the antigen immunoprecipitated by the MoAb CJA3 from the CRC cell lines SW480 and SW620 and from the melanoma cell line MALME-3M revealed a component with a m.w. of 150,000. Preincubation of CRC cell lines SW480 and SW620 with the MoAb CJA3 for 16 hr reduced their susceptibility to NCMC by about 50%. Kinetic experiments showed that prolongation of the incubation of target cells with the MoAb CJA3 resulted in a time-dependent increase in the amount of MoAb bound. Maximum binding of the MoAb CJA3 was reached after 4 hr of incubation. The increase in antigen expression chronologically paralleled the decrease in NCMC target cell sensitivity, suggesting that the membrane alterations induced by the MoAb CJA3 were important for NCMC against these two cell lines.
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PMID:The monoclonal antibody CJA3 down-regulates the susceptibility of human tumor cell lines to natural cell-mediated cytotoxicity. 395 Apr 15

The alterations caused on the structure of melanins by acid and alkaline extraction methods were studied by means of techniques such as Fourier Transform Infrared spectroscopy and thermogravimetry. Acid extraction results in the hydrolysis of aromatic monomers of the pigment, leading to uncyclicized residues and to a less conjugated polymer. Alkaline methods catalyse the covalent binding of proteins present in the melanin extract, thus leading to melanoprotein artifacts. A new method based on the delipidation with ether and deproteinization with SDS of previously isolated melanosomes is proposed. This method shows that melanins present in Harding-Passey mouse melanoma have a bound protein moiety, so that they should exist "in vivo" as melanoprotein complexes. Thermogravimetric data suggest that the chromogen moiety of the melanoproteins in Harding-Passey mouse melanoma is a mixture of eu- and pheomelanins.
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PMID:FT-IR spectroscopy of natural melanins isolated from Harding-Passey mouse melanoma. 408 Aug 27

Wheat germ agglutinin (WGA) binding patterns of human malignant melanoma cell lines with a high or a low ability to grow subcutaneously in nude mice were compared. SDS-PAGE analysis of WGA binding glycoproteins revealed similar qualitative but different quantitative profiles. Striking differences were observed in the density of WGA binding sites, twice as high in the low tumorigenic cell line as in the high tumorigenic cell line. Differences were also observed in the topographical organization of these WGA binding sites patched on the low tumorigenic cell line and diffuse on the high tumorigenic cell line. Fluorescence photobleaching measurements showed clear-cut differences in their motion patterns.
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PMID:Surface distribution of wheat germ agglutinin binding sites of human melanoma cell lines with low and high tumorigenicity. 409 44

Isolation of a melanoma-specific protein (MSP) from human urine has been achieved using antibody affinity chromatography. MSP migrates as a single homogeneous protein on SDS PAGE and comparison of these data and ultracentrifuge analyses indicates that MSP contains a single polypeptide chain. MSP, however, shows considerable charge heterogeneity on isoelectric focusing. The desialo form, alpha 2 MSP, is found predominantly in patients with advanced metastatic disease, whilst only the sialo form alpha 1 MSP, is obtained from the urine of patients with early-stage disease. MSP does not react with antisera raised to alpha 1 foetoprotein (AFP) or carcinoembryonic antigen (CEA) and hence is immunologically distinct from these other tumour-associated glycoproteins. Antisera raised to MSP do not react with normal skin melanocytes nor with any foetal tissue tested, and hence the origin of MSP remains unresolved.
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PMID:Further characterization of a melanoma-specific protein from human urine. 615 65

Antisera were elicited in rabbits with hybrids derived from the fusion of human melanoma cells with murine fibroblasts. Following absorption with cultured human lymphoid cells, Xenoantiserum 8986 reacts with cultured human melanoma cells and other tumors of nonlymphoid origin. Rosette inhibition assays showed that the xenoantiserum reacts with structures which carry the determinants recognized by the monoclonal antibodies 165.28T and 653.25N and which are recognized by a xenoantiserum elicited with cultured human melanoma cells. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the immune complexes formed by reacting spent medium of cultured melanoma cells with Xenoantiserum 8986 showed that the antiserum contains antibodies reacting with a M.W. 240,000 melanoma-associated antigen and a M.W. 94,000 melanoma-associated antigen.
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PMID:Serological and immunochemical analysis of the specificity of xenoantiserum 8986 elicited with hybrids between human melanoma cells and murine fibroblasts. 616 92


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