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)

The purpose of this study has been to compare collagen-gelatin degrading enzymes isolated from cancer cell organelles and cytosol to the metalloproteinases released by cancer cells. To this end, metastatic mouse melanoma cell organelles were isolated by sucrose density gradient centrifugation and metalloproteinases were assayed using native and denatured [methyl-3H]collagen substrates. Solubilized proteinases were purified by ammonium sulfate precipitation, anion exchange, concanavalin A affinity and gel-filtration column chromatographic procedures and characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The conclusions were as follows: malignant melanoma cells have a metalloproteinase (Mr = 59,000) which is shed from cells into conditioned medium as a component of intact membrane vesicles rather than as a soluble enzyme; storage of tumor-conditioned medium leads to the generation of autoactivated soluble metalloproteinases of lower molecular weight; purification of these metalloproteinase species yielded variant collagenases that have considerable gelatinolytic activity and a cleavage preference site for the Gly-Ile bond in a collagen-like synthetic octapeptide substrate which is typical for collagenase-type metalloproteinases. It is proposed that localization of potent proteinases to the surface of cancer cells facilitates the local breakdown of connective tissues during the invasive process.
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PMID:Metastatic mouse melanoma cells release collagen-gelatin degrading metalloproteinases as components of shed membrane vesicles. 303 Apr 44

Malignant tumors may escape rejection by the immune system because they induce a state of immunological tolerance mediated by tumor antigen-specific suppressor T cells. In animal systems, cyclophosphamide can reverse the tolerance and thereby facilitate immunologically mediated tumor destruction. We have applied these concepts to the immunotherapy of human malignant melanoma. Forty-three patients with metastatic disease were treated with a whole cell vaccine 3 days after intravenous administration of cyclophosphamide, 300 mg/m2. The vaccine consisted of cryopreserved, irradiated autologous melanoma cells, obtained from metastatic masses by dissociation with collagenase and DNAse, mixed with bacillus Calmette-Guerin (BCG) and injected intradermally. The cyclophosphamide (CY) + vaccine combination was repeated every 28 days. Delayed-type hypersensitivity (DTH) was tested by injecting 1 x 10(6) melanoma cells intradermally and measuring the diameter of induration at 48 h. Most patients had minimal pretreatment DTH responses to melanoma cells (mean +/- SE, mm = 2.4 +/- 0.5). After two vaccine treatments, the responses increased significantly (mean increase +/- SE = 12.1 +/- 1.6 p less than .001) and that level of response was maintained after 4, 6, and 8 treatments. The patients were also skin-tested with a mixture of the enzymes used to dissociate the tumors. No patients exhibited DTH to collagenase + DNAse prior to vaccine injection, but every patient developed DTH to the mixture following two treatments (mean, mm = 26.4 +/- 3.9). Although extracting viable cells from tumor tissue without the use of enzymes proved difficult, we were able to test DTH to mechanically dissociated tumor cells in 23 patients. After two vaccine treatments, there was a significant increase in DTH to enzyme-free autologous melanoma cells (mean DTH +/- SE, mm: 5.4 +/- 1.0, p less than .01). Whereas 5 of 23 patients had positive DTH responses (5 mm induration or greater) before treatment, 11 of 23 were positive after two treatments. Further significant increases in DTH enzyme-free cells were observed after 6 and 8 treatments. Thus, it appears that patients receiving CY + vaccine developed DTH to tumor-associated antigens as well as to residual collagenase and DNAse on the cell surface. Thirty-three patients could be evaluated for antitumor effects of cyclophosphamide + vaccine. There were 3 complete remissions, 1 partial remission, and 2 minor responses. Two complete responders remain alive and free of disease after 57 and 12 months, respectively, and the third died after 39 months. The partial remission consisted of 75% regression of a pulmonary metastasis.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Active immunotherapy of human melanoma exploiting the immunopotentiating effects of cyclophosphamide. 316 14

First-trimester normal human trophoblast cells show some phenotypic similarities to malignant cells, e.g., rapid proliferation and ability to invade neighboring tissue, including basement membrane in situ, but do not have the ability for unlimited growth or metastasis. The present study examined whether the invasive ability of normal trophoblast cells is an intrinsic property of these cells, independent of the microenvironment provided by the pregnant uterus, and if so, whether they share some of the molecular mechanisms of invasion exercized by metastatic malignant cells. The ability of in vitro grown human trophoblast lines to invade an epithelium-free human amniotic membrane was measured from the temporal kinetics of retention of radioactivity within this membrane resulting from a penetration by 125I-iododeoxyuridine-labeled trophoblast cells. The magnitude of this invasion was compared to that of the highly metastatic human JAR-choriocarcinoma cell line and murine B16F10 melanoma line. Trophoblasts were found to share some of the same molecular mechanisms of invasion with the metastatic cell lines. Inhibitors of collagenase, plasmin, plasminogen, and plasminogen activators completely prevented invasion of the amnion by the trophoblast lines as well as by the metastatic JAR and B16F10 lines. Mersalyl, a compound known to activate collagenase, stimulated invasion by all cell lines tested, including under conditions in which plasmin activity was inhibited. In addition, trophoblasts produced significant levels of type IV collagenase and laminin, both of which appear to be important products of metastatic tumor cells required for basement membrane invasion. It may be concluded from these findings that the invasive property of first trimester human trophoblasts is genetically determined; that the magnitude of amnion invasion cannot differentiate between metastatic cell lines and invasive but nonmetastatic cell lines; and that invasiveness is not a sufficient prerequisite for metastatic ability.
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PMID:Normal nonmetastatic human trophoblast cells share in vitro invasive properties of malignant cells. 317 Jun 42

The human tissue inhibitor of metalloproteinases (TIMP) is a glycoprotein with a molecular weight of 28,000. It appears to be ubiquitous in human mesoderm tissues and has previously been shown to be identical to the collagenase inhibitor isolated from human skin fibroblasts. TIMP inhibits type I- and IV-specific collagenases and other neutral metalloendoproteinases that may be responsible for the degradation of extracellular matrix in tumor cell metastasis. In this work we have utilized recombinant human TIMP (rTIMP) obtained by expression of its cDNA gene (Carmichael et al., Proc. Natl. Acad. Sci. USA, 83:2407, 1986). The rTIMP is shown to have similar inhibition properties as natural TIMP against human skin fibroblast collagenase. In an in vitro amnion invasion assay system, rTIMP inhibited the invasion of B16-F10 murine melanoma cells through the human amniotic membrane at an identical concentration to that reported previously for natural TIMP. The mechanism by which rTIMP inhibits amniotic membrane invasion was compared to the mechanism by which the fibronectin receptor binding peptide RGDS and the aminin receptor binding peptide YIGSR inhibit amnion invasion. RGDS and YIGSR inhibited strong binding of the tumor cells to the amniotic membrane. In contrast rTIMP did not inhibit the cell adhesion step in amnion invasion, but actually increased the number of tumor cells that were tightly bound to the amnion. Thus rTIMP appears to inhibit a later step in the amnion invasion process, following B16-F10 cell adhesion. C57BL/6 mice treated with i.p. injections of rTIMP every 12 h for 6.5 days showed a significant inhibition of metastatic lung colonization by B16-F10 murine melanoma cells. While the rTIMP inhibited the number of metastatic lung tumors formed, it had no significant effect on the size of the lung tumors. Furthermore, tumors grown s.c. in mice receiving 12-h i.p. injections of rTIMP for 6.5 days, as in the in vivo colonization assay, showed no difference in size from controls. Thus the anticolonization effect of rTIMP appears not be due to an effect on tumor growth, but on the invasion step itself. The inhibition of lung colonization in C57BL/6 mice by rTIMP is one of the first examples showing an antimetastatic effect of a selective metalloproteinase inhibitor in a mammalian animal model, and supports an essential role for metalloproteinase(s) in the extravasation and invasion of tumor cells during lung colonization by blood-borne tumor cells.
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PMID:Inhibition by human recombinant tissue inhibitor of metalloproteinases of human amnion invasion and lung colonization by murine B16-F10 melanoma cells. 341 7

BL6 melanoma cells injected subcutaneously in 18-month-old syngeneic C57BL/6 mice elicit a marked fibrotic response highly similar in myofibroblast composition and Type V collagen content to that characterizing the desmoplastic response of human carcinomas. This host response can be quantitated in vivo by measuring both hydroxyproline content (total collagen) and incorporation of intraperitoneally injected [14C] proline into collagenase-sensitive protein (new collagen synthesis). 70% inhibition of the response can be achieved with daily L-3,4-dehydroproline. The response can be similarly quantitated in vitro in explants of desmoplastic tumor tissue. The model allows for subsequent investigations of the effects of the desmoplastic response on tumor invasion and metastasis.
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PMID:An experimental model for studying the desmoplastic response to tumor invasion. 359 24

The ability of cellular vascular components including endothelial cells, smooth muscle cells, and fibroblasts to interact with the collagenolytic activity of invasive human tumor cell lines has been investigated. The human HT1080 fibrosarcoma and Bowe melanoma cells, which rapidly digest collagenous proteins in vitro, failed to dissolve them when cocultivated with bovine endothelial cells. This inhibition was not dependent on the ability of endothelial cells to form a monolayer separating the tumor cells from the collagenous substrate. In contrast, little collagenolysis inhibitory activity was detected in bovine vascular smooth muscle cells and human fibroblasts when compared to endothelial cells. Serum-free medium conditioned by endothelial cells inhibited tumor cell-mediated collagenolysis. Our data further suggest that this inhibition was mediated by secreted collagenase inhibitors, since endothelial cell-conditioned medium did not suppress the production of metalloproteinases by the tumor cells but inhibited the activities of collagenases derived from tadpole, rabbit, and human fibroblasts. Treatment of the endothelial cells with cycloheximide suppressed the collagenase inhibitory activity, demonstrating active production of collagenase inhibitors by the cells. Gel filtration chromatography of endothelial cell-conditioned medium allowed the separation of two distinct peaks with inhibitory activities for vertebrate collagenase in the molecular weight range of 70,000 to 75,000 and 30,000 to 35,000, respectively. While the inhibitor with an approximate molecular weight of 30,000 to 35,000 shared many properties with the tissue inhibitor of metalloproteinases, the high-molecular-weight inhibitor demonstrated characteristics not yet described for any collagenase inhibitor. The production and secretion of inhibitors of vertebrate collagenase by bovine endothelial cells may be of importance in the local control of collagen turnover under physiological as well as pathological conditions.
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PMID:Inhibition of tumor cell collagenolytic activity by bovine endothelial cells. 370 89

BL6 melanoma cells injected s.c. in 18-month C57 BL/6 mice elicit a markedly fibrotic response similar in myofibroblast and collagen composition to that characterizing the desmoplastic response of human breast carcinoma. This host response can be quantitated by measuring hydroxyproline (total collagen) and incorporation of i.p.-injected [14C]proline into collagenase-sensitive protein (new collagen synthesis). Inhibition (70%) of the desmoplastic response can be achieved by daily injections of L-3,4-dehydroproline. Inhibiting the response in this manner promotes local invasion of tumor and increases the incidence of spontaneous pulmonary metastasis. 10(5) BL6 melanoma cells produce tumor nodules with a mean diameter of 1.5 +/- 0.5 cm and mean collagen content of 36 +/- 15 mg/g wet tissue at 4 weeks and 10% incidence of pulmonary metastasis at 7 weeks. L-3,4-dehydroproline produces nodules with a mean diameter of 2.3 +/- 0.5 cm and mean collagen content of 12 +/- 2 mg/g with a 40% incidence of metastasis. L-3,4-dehydroproline exerts a selective effect on myofibroblast collagen synthesis in vitro and no effect on [3H]thymidine uptake, doubling time, and viability of BL6 cells and myofibroblasts. Furthermore, this drug exerts no effect on BL6 invasion and metastasis in 6-week C57 BL/6 mice, hosts which exhibit a negligible desmoplastic response.
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PMID:Increased invasion and spontaneous metastasis of BL6 melanoma with inhibition of the desmoplastic response in C57 BL/6 mice. 381 62

A 140 K glycoprotein was detected in the culture media of human sarcoma and melanoma cell lines by labeling with several radioactive amino acid and sugar precursors, followed by sodium dodecylsulfate-polyacrylamide gel electrophoresis and fluorography. In contrast to this, in the culture media of metabolically labeled embryonic and skin fibroblasts this glycoprotein was not found. Likewise, a protein with an identical molecular weight of 140 K was also found in culture media after cell surface labeling of the neoplastic cells but not in the culture media from control cells. The [35S]methionine-labeled 140 K was not split by collagenase and did not appear to be a fragment of fibronectin. We discuss the possibility that secretion of the 140 K glycoprotein is a transformation-related phenomenon.
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PMID:Release of an Mr 140,000 glycoprotein in the culture media of certain human sarcoma and melanoma cell lines. 400 10

The aggregating properties of murine melanoma cell lines with low metastatic potential (B16-F1) and high metastatic potential (B16-F10 and B16-BL6) were compared. All three types of cells were found to possess Ca2+-dependent and Ca2+-independent intrinsic mechanisms for cell adhesion, though the extent of reaggregation varied in each mechanism. After trypsin treatment at around 1 microgram/ml, F10 and BL6 cells reaggregated in the presence of 1mM Ca2+ to a greater degree than F1 cells. F10 and BL6 cells were also more aggregative than F1 cells after dissociation with collagenase. The apparent adhesiveness of the cells was found to be dependent on both the manner of cell preparation for reaggregation and on the presence of external Ca2+ or serum factors. The results are discussed in relation to the mechanisms of tumor cell arrest with emphasis on the effect of extracellular factors on cell adhesiveness.
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PMID:Adhesive properties of weakly and highly metastatic melanoma cell lines. 608 47

Characterization of cells comprising solid tumors will facilitate the rational design of cancer chemotherapy for individual patients. We have prepared cell suspensions from human melanoma, sarcoma, and lung tumors by thinly slicing the tissue with a microtome and scalpels (mechanical release), followed by treatment with a mixture of collagenase II and DNase I (enzymatic release). This method of disaggregation resulted in two cell suspensions for each tumor specimen, and we characterized these suspensions by assessing their dye exclusion capability, ribonucleoside triphosphate pools, cytological profile and clonogenicity in soft agar. The enzymatic method thus yields cells in addition to those obtainable by a mild mechanical procedure, and these cells are similar in cytological profile and clonogenicity in soft agar to those released mechanically. Furthermore, the enzymatically released population is superior to that released mechanically for purposes requiring large numbers of dye-excluding cells having intact ribonucleotide pools.
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PMID:Characterization of cells obtained by mechanical and enzymatic means from human melanoma, sarcoma, and lung tumors. 626 Mar 39


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