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 antibody HBCA-12 obtained by hybridoma procedure after immunization with human mammary adenocarcinoma cell line MDA-MB-231 immunoprecipitated a cell surface sialoglycoprotein gp80 (apparent molecular weight 80 000) from MDA-MB-231 cells and a glycoprotein gp78 from human myeloma cell line ARH 77. A protein of a similar electrophoretic mobility was immunoprecipitated also from 35S-methionine metabolically radiolabeled human melanoma cell line VUP 1. The expression of the antigen recognized by HBCA-12 monoclonal antibody could be detected neither on PHA-induced nor on EBV-transformed peripheral blood mononuclear cells from healthy donors.
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PMID:Biochemical and histochemical characteristics of target antigen detected by monoclonal antibody HBCA-12 against a membrane component of human mammary carcinoma cell line. 652 96

An acid-stable transforming growth factor (TGF) that interacts with epidermal growth factor (EGF) receptors and is structurally related to EGF was isolated from serum-free culture fluids of Snyder-Theilen feline sarcoma virus-transformed rat embryo (FeSV-Fre) cells. Purification of this EGF-like TGF (eTGF) was achieved by molecular filtration chromatography and successive reverse-phase high pressure liquid chromatography steps on octadecyl support eluted with acetonitrile and 1-propanol gradients, respectively. Rat eTGF consists of a 7.4-kD single polypeptide chain that co-migrates with biological activity in dodecyl sulfate-polyacrylamide electrophoresis gels. Like preparations of a related TGF from human melanoma cells (Marquardt, H., and Todaro, G.J. (1982) J. Biol. Chem. 257, 5220-5225), but unlike EGF from rat, human, or mouse, rat eTGF has phenylalanine and lacks methionine. However, the sequence of the first 30 amino acid residues in rat eTGF is H2N-Val-Val-Ser-His-Phe-Asn-Lys-Cys-Pro-Asp-Ser-His-Thr-Gln-Tyr-Cys-Phe-His-Gly - Thr-(x)-Arg-Phe-Leu-Val-Gln-Glu-Glu-(Lys)-(Lys)-, which is significantly (20% and 28%) homologous to the NH2-terminal region of mouse EGF and human EGF, respectively. In addition to eTGF, molecular filtration chromatography of acid-soluble extracts from medium conditioned by FeSV-Fre cells resolved a 14-kD transforming factor(s) apparently devoid of intrinsic mitogenic activity but able to elicit a strong anchorage-independent growth response in the presence of eTGF or EGF. These results show that: 1) a 7.4-kDa TGF structurally and functionally related to EGF has been isolated from FeSV-Fre cells and 2) the full anchorage-independent growth-promoting activity of medium conditioned by FeSV-Fre cells is due to the coordinate action of at least two types of factors, the 7.4-kDa eTGF and a second 14-kDa transforming factor(s).
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PMID:Epidermal growth factor-like transforming growth factor. I. Isolation, chemical characterization, and potentiation by other transforming factors from feline sarcoma virus-transformed rat cells. 660 68

The cancericidal efficacy of a new synthetic tripeptide was demonstrated using both in vitro cultures and in vivo tumorigenic assays. The antitumor agent PTT.119 (p-F-Phe-m-bis-(2-chloroethyl)amino-Phe-Met ethoxy HCl) was highly effective against three virulent murine tumor models: the L1210 leukemia, MJY-alpha mammary tumor and B16 melanoma. Treatment of tumor cells for periods as short as 15 min to 4 h with concentrations of 1-50 micrograms PTT.119/ml irreversibly reduced tumor cell viability, as evidenced by vital dye exclusion and abrogation of tumor formation and prolongation of host survival. Examination of the sensitivity of mice to PTT.119 revealed that the in vitro antitumor activity of the synthetic tripeptide was exerted at concentrations easily attainable and well tolerated in vivo.
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PMID:Increased cancericidal activity of PTT.119; a new synthetic bis-(2-chloroethyl)amino-L-phenylalanine derivative with carrier amino acids. II. In vivo bioassay. 669 28

Human malignant melanoma cell line SK-MEL-37 expresses HLA-DR antigens having a characteristic 2-chain structure, with heavy chains (alpha) of approximately 32,000 daltons and light chains (beta) of approximately 28,000 daltons. Nonequilibrium pH-gradient electrophoresis (NEPHGE) on HLA-DR immunoprecipitated by rabbit anti-HLA-DR sera from [35S]-methionine-labeled, pulse-chased cells showed 2 closely spaced heavy-chain components (1, 2) and 4 light-chain spots (3-6). From nonchased samples, numerous more-basic components running in the heavy chain region were also precipitated. In particular, a very basic, 30,000 dalton component (pl approximately 8.5) was prominent (component 7); this spot probably corresponds to the invariant (Ii) peptide previously demonstrated in lymphoid cell HLA-DR precipitates (9) and the M-1 peptide of Shackelford and Strominger (10). None of these components (alpha, beta, or component 7) was precipitated from extracts of HLA-DR-negative melanoma cells. Pulse-chase experiments and the use of different labeled sugar precursors showed that component 7 is a partially glycosylated intracellular precursor, possibly of the HLA-DR alpha-chain. None of the immunoprecipitates, even from cells pulse-labeled for only 15 min, contained a peptide migrating in the 55,000 to 60,000 m.w. region. It was concluded that melanoma HLA-DR is not synthesized via a polyprotein precursor. In contrast to these results, obtained with rabbit anti-HLA-DR sera, a mouse monoclonal anti-HLA-DR was found to precipitate only biosynthetically completed alpha (1, 2) and beta (3-6) chains.
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PMID:Analysis of the biosynthesis of HLA-DR glycoproteins in human malignant melanoma cell lines. 678 52

Radioimmunoprecipitation followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to study the distribution on human lymphoid cells of a previously undescribed surface antigen recognized by several heteroantisera. A glycoprotein with a 90,000 mol wt (under reducing conditions) was detected on all cell lines tested including T, B, null, and myeloid cell lines, although the amount of antigen present varied considerably. The antigen was absent from normal peripheral blood lymphocytes (PBL), B and T cells, monocytes, granulocytes, thymocytes, and erythrocytes. After stimulation with lectins or allogeneic B cells, the antigen was induced on PBL T cells. A limited number of leukemic T cells tested all expressed the antigen, as did melanoma cell line and human embryonic lung fibroblasts. Hence, the antigen was present only on dividing lymphoid cells and absent from nondividing cells, but was also present on the two examples of dividing non-lymphoid cells tested. Under nonreducing conditions, the 90,000-mol wt band normally present disappeared to be replaced by another at approximately 200,000 mol wt. The glycoprotein bound to lectins from lentil and ricin, but not to wheat germ agglutinin. It could be readily labeled metabolically by [35S]methionine or by surface iodination, and appeared to be a major membrane protein on some cell lines.
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PMID:Novel surface antigen expressed on dividing cells but absent from nondividing cells. 696 14

1. Linear uptake of tyrosine lasted for 1 min in cultured B-16 mouse melanoma cells preloaded with an amino acid such as tyrosine. 2. The tyrosine uptake increased markedly on preincubating the cells with 0.1 mM methionine, tyrosine, histidine or tryptophan and moderately with 1 mM phenylalanine, valine, isoleucine, or leucine. The effects of the preincubation on leucine uptake were similar to those on tyrosine uptake. 3. The tyrosine uptake was Na-independent under the experimental conditions used (0.05-1.0 mM); Km 75 micrometers and Vmax 15 nmol/min/mg protein. The methionine uptake (0.1-0.5 mM) was also Na-independent (Km 150 micrometers and Vmax 25 nmol/min/mg protein), whereas Na-dependent uptake could contribute at 2 mM methionine. 4. Inhibitions of tyrosine uptake by tryptophan, phenylalanine, leucine, isoleucine, methionine, valine, and histidine were competitive, giving K1 values of 70, 80, 100, 130, 160, 350, and 900 micrometers, respectively. 5. Exchange between intracellular methionine and extracellular tyrosine and vice versa was equimolar. Potencies of amino acids in stimulating tyrosine efflux were in the following order: methionine greater than tyrosine greater than histidine greater than tryptophan greater than phenylalanine greater than leucine greater than isoleucine much greater than valine. 6. The amino acid affinity of the system in the intracellular surface was suggested to be different from that in the extracellular surface. 7. The theophylline-treated cells showed a marked increase in tyrosine-uptake rate with elevated Vmax and unchanged Km.
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PMID:Studies on the transport of tyrosine, leucine, and methionine in cultured B-16 mouse melanoma cells. 713 Jan 45

Retinoic acid reduces the growth rate of mouse S91 melanoma cells in culture and increases the proportion of cells in the G1 phase of the cell cycle. Because of the integral role protein synthesis has been shown to play in growth control we studied the effect of retinoic acid on the protein synthesis machinery with a cell-free system developed from the melanoma cells. This system was capable of translating endogenous mRNA, exogenous globin mRNA, and the synthetic template poly(U). Of the above activities of the protein synthesis system only the translation of endogenous mRNA was reduced significantly in the cell-free system prepared from retinoic acid-treated cells. Analyses of the amount and function of RNA revealed that treatment with retinoic acid leads to reductions in total RNA content, in the proportion of ribosomes in polysomes, in the amount of poly(A)RNA, and in the amount of polysome-associated mRNA. All these effects of retinoic acid contribute to the decrease in protein synthesis activity of treated cells. Two-dimensional electrophoresis analysis of L-[35S]methionine-labeled proteins produced by untreated and treated cells revealed only a few quantitative differences. We suggest that retinoic acid-induced suppression of protein synthesis activity may be the cause for growth inhibition.
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PMID:Effects of retinoic acid on protein synthesis in cultured melanoma cells. 713 Feb 90

The present studies examined the biochemical characteristics which were carried on from parent cells during fusion of human skin fibroblasts (HSF) with spleen cells of BALB/c mice preimmunized with hormone-responsive and nonresponsive human malignant melanoma cells (HMMC-ShA and HMMC-SR). The melanoma cells used as immunogens were either unmodified or preincubated with vibrio cholera neuraminidase (VCN), with estradiol (E), or with progesterone (P). Responsiveness was monitored by (3H) thymidine and (35S) methionine incorporation. Responsiveness to estradiol, concanavalin A (Con A) and to phytoheamagglutinin (PHA) were carried out, whereas malignancy was suppressed extensively in the cloned hybrids. On the immunizing tumor cells, VCN treatment enhanced (3H) thymidine but reduced (35S)-methionine incorporation and malignancy of the estradiol responsive melanoma cells (HMMC-ShA). VCN treatment enhanced (3H)-thymidine incorporation, but had no effect on (35S)-methionine incorporation and malignancy of the estradiol nonresponsive HMMC-SR cells. Estradiol treatment enhanced plasminogen activator (PA) activity and malignancy, whereas progesterone treatment reduced (inhibited) plasminogen activator activity and suppressed malignancy of the immunizing tumor cells. The PA from estradiol-responsive and from nonresponsive melanoma cells differed in their electrophoretic mobility on polyacrylamide gel electrophoresis.
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PMID:Correlation between plasminogen activator activity of immunizing tumor cells and complement-mediated cytotoxic antibodies secreted by cloned hybrid cells. 719 36

The synthesis and purification of several analogues of the melanotropins with amino acid substitutions at the tyrosine-2 and methionine-4(7) positions are reported. The compounds synthesized included [4-norleucine]-alpha-MSH, [7-norleucine]-beta p-MSH, [2-3',5'-diiodotyrosine]-alpha-MSH, [2-D-tyrosine]-alpha-MSH, and [2-phenylalanine,4-norleucine]-alpha-MSH. The biological activities of these derivatives were measured and compared on normal melanocytes (frog skins) and on transformed melanocytes (mouse melanoma adenylate cyclase), over the entire dose-response range. All compounds tested were full agonists in both assay systems but varied considerably in potency. The relative potencies in the frog skin assay (alpha-MSH = 1.0) were as follows: [Nle7]-beta p-MSH (5.2) > [Nle4]-alpha-MSH (2.3) > alpha-MSH (1.0) > [Phe2,Nle4]-alpha-MSH (0.80) > beta p-MSH (0.55) > [I2-Tyr2]-alpha-MSH (0.12) > [D-Tyr2]-alpha-MSH (0.04). The relative potencies in the melanoma adenylate cyclase system were [Nle7]-beta p-MSH (4.2) > beta p-MSH (2.2) > [Nle4]-alpha-MSH (2.0) > alpha-MSH (1.0) approximately equal to [Phe2,Nle4]-alpha-MSH (0.9) > [I2-Tyr2]-alpha-MSH (0.40) > [D-Tyr2]-alpha-MSH (0.20). There appears to be some differences in structural specificity at the melanotropin receptors of the two cell systems.
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PMID:Synthesis and structure-function studies of melanocyte stimulating hormone analogues modified in the 2 and 4(7) positions: comparison of activities on frog skin melanophores and melanoma adenylate cyclase. 745 98

We investigated the expression of alpha v-integrins in different stages of human cutaneous melanocytic tumor progression. We observed that alpha v beta 5 was the alpha v-integrin expressed in all common nevocellular nevi, in 78% of dysplastic nevi, in 63% of early primary melanomas, in 43% of advanced primary melanomas, and in 33% of melanoma metastases. Hence, loss of alpha v beta 5 expression was related to melanocytic tumor progression. In line with earlier reports, alpha v beta 3 was exclusively detected in advanced primary melanomas and metastases (24% and 50% respectively). Staining with anti-alpha v monoclonal antibodies (MAbs) in lesions where both alpha v beta 3 and alpha v beta 5 were absent showed that alternative alpha v-integrins were expressed in advanced primary melanomas and metastases. By FACS analysis, we determined expression of alpha v beta 5 and alpha v beta 3 in 4 human melanoma cell lines with different metastatic capacities after s.c. inoculation into nude mice. One of the non-metastatic and both highly metastatic cell lines expressed alpha v beta 5 at their surface. Surprisingly, alpha v beta 3 was detected exclusively in the non-metastatic cell lines. Absence of alpha v beta 3 in the highly metastatic cell lines was confirmed by lack of immunoprecipitation from 35S-methionine-labeled cells and by absence of immunohistochemical staining on primary and metastatic xenograft lesions. Our findings indicate that alpha v beta 5 expression is often lost in advanced stages of melanocytic tumor progression in situ, while alpha v beta 3 is acquired, but that a decrease in alpha v beta 5 and an increase in alpha v beta 3 expression are not necessarily related to the metastatic behavior of human melanoma cells in nude mice.
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PMID:Alpha v-integrins in human melanoma: gain of alpha v beta 3 and loss of alpha v beta 5 are related to tumor progression in situ but not to metastatic capacity of cell lines in nude mice. 753 77


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