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)

K-1735 clones 10 and M2 are cell lines cloned from a UV-induced murine melanoma. While both lines are highly tumorigenic, only the M2 cells are highly invasive in vitro and metastatic in vivo. Here we have exposed the clone 10 cells to the synthetic peptide PA22-2, which contains the IKVAV sequence from the A chain of laminin and which, like laminin, induces collagenase IV production and enhances metastasis formation by B16F10 cells. Zymogram analysis of conditioned media from clone 10 cells cultured on the peptide demonstrated a dose-dependent increase in collagenase IV activity. When clone 10 cells were cultured on a reconstituted basement membrane (Matrigel), this peptide caused an invasive phenotype comparable to the M2 cells. The invasive clone 10 cells were, however, unable to form lung colonies in vivo in the presence of this peptide. We conclude that this peptide represents an active site on laminin which is able to stimulate the invasiveness of this tumor cell line, but that this activity is not sufficient to confer metastatic potential.
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PMID:Induction of an invasive phenotype in benign tumor cells with a laminin A-chain synthetic peptide. 129 29

During the process of tumor cell invasion and metastasis, tumor cells are known to interact with extracellular matrix proteins, endothelial cells, platelets and other organ-specific structures. Integrins are cell surface molecules which mediate cell-matrix and cell-cell interactions and are likely to be important for tumor cell survival and dissemination. The purpose of this study was to characterize the integrin and proteolytic enzyme repertoire from low (A375P), medium (A375M) and high metastatic (A375SM) human melanoma cell lines. These cell lines are also invasive through human amniotic membranes in vitro and their invasiveness parallels the reported metastatic phenotype. The types and levels of expression of the various integrin receptors were analysed by quantitative immunoprecipitation using a panel of monoclonal antibodies directed to known integrin subunits. In addition, cDNA probes to the integrin subunits were used in quantitative northern blot analysis. These data show that the integrin alpha v beta 3 increases 50- to 100-fold as these cells progress to a more metastatic phenotype. alpha 4 beta 1 levels also appeared to increase several fold, while other beta 1 integrins did not differ in their expression levels. The increased alpha v beta 3 expression in the more metastatic cells resulted in an increased adhesion to vitronectin and fibrinogen substrates in cell attachment assays. However, alpha v- and beta 3-specific antibodies did not inhibit A375 cell invasion through the amnion. Each cell line was found to release similar quantities of a 72-kDa gelatinase/type IV collagenase and tissue type plasminogen activator. These results suggest that during the progression of these tumor cells from a low to high metastatic phenotype, marked changes in integrin expression occurred which may facilitate interactions with platelets, endothelial cells and specific extracellular matrix proteins to promote metastasis.
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PMID:Integrin expression in human melanoma cells with differing invasive and metastatic properties. 131 Dec 25

The primary structure of tumor invasion-inhibiting factor 2 (IIF-2) purified from bovine liver (A. Isoai et al., Jpn. J. Cancer Res., 81:909-914, 1990) was determined. A computer homology search of the National Biomedical Research Foundation data bank revealed that IIF-2 is identical to the carboxyl-terminal region, residue number [69-89], of high mobility group 17 which is a DNA-binding non-histone protein. IIF-2 synthesized by an automated peptide synthesizer showed similar invasion-inhibitory activity as compared with the purified factor, when tested with the monolayer invasion assay system using highly invasive rat ascites tumor cells. When examined with the other in vitro assay systems using a modified Boyden chamber, the synthetic IIF-2 suppressed the chemotactic migration of highly metastatic B16 melanoma (B16FE7) cells to fibronectin or laminin and invasion through Matrigel. The IIF-2 inhibited neither the cell proliferation nor the binding of cells to fibronectin or Matrigel and also showed no significant inhibition of Mr 90,000 type IV collagenase (gelatinase) obtained from human schwannoma (YST-3) cells. The formation of lung colonies in mice given injections of B16FE7 and Lewis lung carcinoma cells was significantly reduced by the coinjection of the IIF-2. These results suggest that IIF-2 suppresses tumor invasion by impairing cell motility and inhibits the migration of metastasizing cells through extracellular matrix (extravasation steps) following their arrest in the capillary bed of the lung in vivo.
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PMID:Tumor invasion-inhibiting factor 2: primary structure and inhibitory effect on invasion in vitro and pulmonary metastasis of tumor cells. 131 31

Cell clones derived from a human melanoma metastasis selected for different integrin profiles were examined in vitro for invasive potential and biological and biochemical features potentially related to this process. Clones which expressed high levels of integrins showed high invasive potential, extracellular matrix degradation, and adhesion to gelatin-coated substrates. A correlation was also found between invasiveness and intracellular and extracellular plasminogen activator activity. Heparanase and collagenase type IV activities were apparently unrelated to invasiveness. gamma-Glutamyl transferase (GGT) activity was high in highly invasive clones, whereas melanin content was high in slightly invasive clones. Heterogeneity was also observed in cellular parameters such as cell dimensions, growth features and DNA index. The intrinsic biological and biochemical heterogeneity of a cell population derived from a single metastasis may be responsible for the different behaviour of clones, regardless of their invasive potential. Since slightly invasive cells are more differentiated than highly invasive cells, malignancy and differentiation are inversely correlated in such human melanoma clones.
Melanoma Res 1992 Dec
PMID:Biological and enzymatic features of human melanoma clones with different invasive potential. 136 80

The human melanoma cell line A375M expresses the vitronectin receptor (alpha v beta 3 integrin) on its cell surface. Treatment of A375M cells with either polyclonal or monoclonal anti-alpha v beta 3 antibodies resulted in stimulation of invasion through basement membrane matrices in vitro. Similar treatment of these cells with a monoclonal anti-alpha v antibody, which does not inhibit the adhesive function of the alpha v beta 3 antigen, also stimulated invasion; however, anti-beta 3 antibody treatment had no effect. Furthermore, pretreatment of the cells with vitronectin or addition of vitronectin to the basement membrane matrix also resulted in stimulation of invasion. Similar treatments with fibronectin receptor antibody or fibronectin had no effect on invasion. Analysis of type IV collagenase expression in cells treated with anti-alpha v beta 3 antibody showed higher levels of both the secreted 72-kDa enzyme and its mRNA. Signal transduction through the alpha v beta 3 integrin could underlie the elevated expression of metalloproteinase and the enhanced invasion of A375M cells through basement membrane matrices.
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PMID:Role of the alpha v beta 3 integrin in human melanoma cell invasion. 137 77

Intracerebral hemorrhage occurs in tumors, stroke and head trauma. Proteolysis of the extracellular matrix around cerebral capillaries by naturally occurring mammalian 72-kDa type IV collagenase may initiate this pathologic event. To investigate this hypothesis adult rats underwent intracerebral injection of type IV collagenase purified from human melanoma cells. Histologically, at 4 h there was perivascular cellular infiltration with hemorrhage, and by 24 h there was infarction with necrosis, edema and hemorrhage. Ultrastructurally, the basal lamina of endothelial cells was disrupted at 2 h. Brain uptake of [14C]dextran and [3H]sucrose increased after intracerebral injection of type IV collagenase compared to controls (P less than 0.0001). Tissue inhibitor of metalloproteinase-2 (TIMP-2) reduced the tracer uptake (P less than 0.02). Metalloproteinase inhibitors reduce extracellular matrix proteolysis and protect the blood-brain barrier.
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PMID:TIMP-2 reduces proteolytic opening of blood-brain barrier by type IV collagenase. 138 Dec 61

Human melanoma cells secrete a 21 kDa protein which binds with 1:1 molar stoichiometry to the matrix metalloproteinase type IV collagenase proenzyme (70 kDa gelatinase) secreted by the same cells. We have purified this binding protein and determined its complete primary structure by directly sequencing overlapping peptide fragments which span the entire protein. We refer to this protein as CSC-21K based on the amino-terminal amino acids CSC and the apparent molecular weight of 21,000 daltons on gel electrophoresis. The amino acid sequence of CSC-21K demonstrates that this protein shares significant homology with human TIMP (tissue inhibitor of metalloproteinase), including conservation of the positions of the twelve cysteine residues and three of four tryptophan residues. The identification of CSC-21K now indicates that a family of TIMP-related proteins exists. Individual members of this family may possess selective affinities for different members of the matrix metalloproteinase family. Based on its sequence homology to TIMP and ability to inhibit type IV collagenolysis we propose the name TIMP-2 for this inhibitor. TIMP-2 produced by tumor cells can also be considered as an onco-suppressor gene product, because it could play an important role in regulating the metalloproteinases involved in tumor invasion and angiogenesis.
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PMID:TIMP-2: identification and characterization of a new member of the metalloproteinase inhibitor family. 148 41

A basal promoter for the Mr 72,000 type IV collagenase gene was specifically defined by chloramphenicol acetyltransferase assays of a nested set of 5' upstream fragments containing the promoter region. This core promoter is TACATCT and is a noncanonical TATA box that fits the TATA consensus sequence. This sequence begins 26 base pairs in the upstream direction from the start site of transcription for the type IV collagenase gene. This basal promoter is active in the highly metastatic A2058 melanoma cell line. A putative enhancer was found between nucleotides -223 to -422 that produces a 7-fold increase in transcriptional activity in the A2058 melanoma cell line. The region immediately 5' of the basal promoter, upstream to position -422, contains a silencer and represses transcriptional activity in the nonmetastatic HT144 melanoma cell line. The results of this study are consistent with previous data that found high expression of Mr 72,000 type IV collagenase mRNA and enzymatic activity in the A2058 cell line, whereas low mRNA expression and type IV collagenase activity were found in the HT144 cell line.
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PMID:Identification of a basal promoter for the human Mr 72,000 type IV collagenase gene and enhanced expression in a highly metastatic cell line. 165 82

A 48 h pretreatment of two malignant and invasive human melanoma cell lines with either swainsonine (an inhibitor of Golgi alpha-mannosidase II) or deoxymannojirimycin (a Golgi alpha-mannosidase I inhibitor) resulted in a dose-dependent decrease in the cells' ability to invade a reconstituted basement membrane in vitro. This effect was reversible within 48 h of removing the drugs. Treatment with either drug resulted in both cell lines being more resistant to the cytotoxic effects of the lectin leukoagglutinin (PHA-L) and more sensitive to the lectin concanavalin A which indirectly indicated a change in the cell surface oligosaccharide composition and structure consistent with the known effects of these drugs on N-linked oligosaccharide processing. A 25-33% decrease was noted in the adhesion of treated cells to either a reconstituted basement membrane or human umbilical vein endothelial cell monolayer while no change was measured in the cells' proliferative rates. A correlative decrease was observed, however, in the expression of human type IV collagenase mRNA which was recovered within 48 h of removing the drugs. These results suggest that a correlation exists between the drug-induced changes in the cell surface oligosaccharide composition and structure with a concomitant decrease in the mRNA and secreted levels of type IV collagenase and the ability of these cells to invade.
Melanoma Res
PMID:Human melanoma cell invasion is inhibited in vitro by swainsonine and deoxymannojirimycin with a concomitant decrease in collagenase IV expression. 166 68

Verapamil, a calcium channel antagonist, inhibits murine B16 melanoma and colon adenocarcinoma C26 tumor metastasis by altering platelet aggregation [Tsuruo, T., et al. (1985) Cancer Chemother. Pharmacol., 14:30-33]. However, the role of calcium homeostasis in regulating several biochemical pathways implicated in other steps of the metastatic cascade suggests that calcium channel antagonists could also inhibit metastasis by other mechanisms. In this report, non-toxic doses of verapamil reversibly decreased human A375M and C8161 melanoma cell invasion and metastasis in a dose-dependent manner. Verapamil reduced cellular invasion and metastases by up to 96% (range 78-96%). Concomitantly, verapamil disrupts microtubule and microfilament organization and inhibits unidirectional cell migration but does not affect cellular adhesion to endothelial monolayers or reconstituted basement membranes. In addition, tumor cells treated with verapamil have a decrease in mRNA of type IV collagenase, a proteinase important in tumor cell degradation of basement membranes. Collectively, these data offer additional evidence regarding the mechanisms of action of verapamil as an anti-metastatic agent.
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PMID:Inhibition of tumor cell invasion by verapamil. 166 59


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