Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An in vitro model, called the Membrane Invasion Culture System (MICS), was used to study the invasive potential of an Epstein-Barr virus (EBV) positive lymphoblastoid cell line (LCL), an EBV-negative Burkitt lymphoma (BL) cell line of American origin and an EBV-positive BL of African origin. MICS measured the ability of these cell lines to invade reconstituted basement membrane-coated filters, which correlated with their tumorigenic and metastatic capabilities in a SCID mouse model. Furthermore, the significantly greater invasive behaviour of the EBV-positive LCL was directly correlated with the cells' ability to express and secrete human type IV collagenase (72 kDa), an important metalloproteinase responsible for the degradation of collagen IV in basement membranes. The data suggest that MICS and the SCID mouse are useful tests of tumorigenicity in lymphoid cells, with measurable effects in both systems related to human type IV collagenase activity. Both models allow further exploration of malignant phenotypes associated with EBV transformation of lymphoid tissues.
Mol Cell Probes 1992 Feb
PMID:Expression of type IV collagenase correlates with the invasion of human lymphoblastoid cell lines and pathogenesis in SCID mice. 131 23

Proteolysis by type IV collagenase (T4) has been implicated in the process of tumor metastasis. The T4 gene is expressed in fibroblasts, but not in normal epithelial cells, and its expression is specifically repressed by the E1A oncogene of adenovirus. We present an investigation of the transcriptional elements responsible for basal, E1A-repressible, and tissue-specific expression. 5'-Deletion analysis, DNase I footprinting, and gel mobility shift assays revealed a strong, E1A-repressible enhancer element, r2, located about 1,650 bp upstream of the start site. This enhancer bound a protein with binding specificity very similar to that of the transcription factor AP-2. A potent silencer sequence was found 2 to 5 bp downstream of this enhancer. The silencer repressed transcription from either r2 or AP-1 enhancer elements and in the context of either type IV collagenase or thymidine kinase (tk) gene core promoters; enhancerless transcription from the latter core promoter was also repressed. Comprising the silencer were two contiguous, autonomously functioning silencer elements. Negative regulation of T4 transcription by at least two factors was demonstrated. mcf-7 proteins specifically binding both elements were detected by gel mobility shift assays; a protein of approximately 185 kDa that bound to one of these elements was detected by DNA-protein cross-linking. The silencer repressed transcription, in an r2 enhancer-tk promoter context, much more efficiently in T4-nonproducing cells (mcf-7 or HeLa) than in T4-producing cells (HT1080), suggesting that cell type-specific silencing may contribute to the regulation of this gene.
Mol Cell Biol 1990 Dec
PMID:Positive and negative transcriptional elements of the human type IV collagenase gene. 217 9

Activated ras oncogene transfection into suitable recipient cells has been shown to induce the metastatic phenotype (Thorgeirsson, et al., Mol. Cell. Biol., 5: 259-262, 1985). We have used this model system to study the correlation of basement membrane collagenolysis with metastatic propensity. The c-Ha-ras oncogene alone, or combined with v-myc, transfected into early passage rat embryo fibroblasts, induce these cells to secrete high levels of type IV collagenolytic metalloproteinase and to concomitantly exhibit a high incidence of spontaneous metastases in nude mice. Cotransfection of c-Ha-ras plus the adenovirus type 2 E1a gene yields cells which are highly tumorigenic but nonmetastatic and fail to produce type IV collagenase. This effect is due to a suppression of collagenase elaboration, not increased production of a collagenase inhibitor, and not decreased production of a collagenase activator. The characteristics of the collagenase are identical to tumor type IV collagenase described previously. The nonmetastatic cells which failed to produce type IV collagenase retain the ability to secrete high levels of plasminogen activator. Transfection with the protooncogenic forms of Ha-ras or mos, or spontaneous transformation of NIH 3T3 cells or chemical transformation of BALB 3T3 cells yields cells which fail to produce collagenase, are tumorigenic, but totally nonmetastatic. These data support a biochemical linkage of type IV collagenase expression with the metastatic phenotype in this rodent system.
...
PMID:Secretion of type IV collagenolytic protease and metastatic phenotype: induction by transfection with c-Ha-ras but not c-Ha-ras plus Ad2-E1a. 302 10

NIH/3T3 cells transfected with DNA from malignant human tumors produced experimental and spontaneous metastases in nude mice. In contrast, parent or spontaneously transformed NIH/3T3 cells failed to metastasize. The transfected clones contained either activated c-Harvey-ras or N-ras oncogenes. A representative clone (T71-17SA2) which was used to assess selected cellular and host factors relevant to the metastatic process produced lung metastases in 100% of the NIH nude mice recipients, secreted augmented levels of type IV collagenase, and invaded human amnion basement membrane in vitro. Expression of the metastatic phenotype was not related to decreased sensitivity to natural killer cells or macrophage-mediated cytotoxicity. Analysis of the cellular DNA from the T71-17SA2 transfectant and its corresponding metastases, both of which contained activated N-ras oncogenes, revealed a twofold increase in the N-ras-specific DNA sequences in the metastatic cells. Thus, transfection with human tumor DNA containing activated ras oncogenes can induce the complete metastatic phenotype in NIH/3T3 cells by a mechanism apparently unrelated to immune cell killing.
Mol Cell Biol 1985 Jan
PMID:NIH/3T3 cells transfected with human tumor DNA containing activated ras oncogenes express the metastatic phenotype in nude mice. 398 18

Simultaneous presence of gelatinase A (MMP-2) and MMP-2 messenger RNA (mRNA) in 30 malignant tumors with various degrees of differentiation and biological behavior was evaluated by immunohistochemistry and in situ hybridization. The series consisted of 10 gastric carcinomas, 10 colorectal carcinomas, five squamous skin carcinomas, and five basal cell skin tumors. MMP-2 was detected in all cases. MMP-2 mRNA was expressed in the stromal cells in all cases and was more marked in the less-differentiated gastric and colonic carcinomas; it was also detected in the neoplastic cells of poorly differentiated tumors, particularly in those of the signet-ring cell type, both in the colon and stomach. The study confirmed that stromal cells have a specific role in tumor invasion and suggests a direct relationship between neoplastic epithelium and stromal cells in the most aggressive varieties.
Diagn Mol Pathol 1994 Sep
PMID:Gelatinase A (MMP-2) and its mRNA detected in both neoplastic and stromal cells of tumors with different invasive and metastatic properties. 798 91

The metalloproteinase matrilysin is widely expressed in the epithelial tumor cells of malignant colorectal adenocarcinomas. Approximately 50% of benign adenomas also express low levels of matrilysin that is focally localized. The expression of stromelysin-1, stromelysin-3, and gelatinase A was observed in the stromal component of several carcinomas and was not present in adenomatous tissue. The expression of interstitial collagenase and gelatinase B was observed in occasional adenomas and carcinomas. Stromelysin-2 transcripts were not detectable in any of the samples examined. Tissue inhibitor of metalloproteinase-1 gene expression was widespread and was observed in both epithelial and stromal cells of adenomas and carcinomas. These results indicate that matrilysin gene expression is an early event in colorectal tumorigenesis and that the expression of stromelysin-1, stromelysin-3, and gelatinase A is primarily a late event. The observed gene expression patterns suggest that matrilysin may participate in early events in tumor progression and that multiple members of the metalloproteinase family may work in concert to facilitate late-stage tumor invasion and metastasis.
Mol Carcinog 1994 Aug
PMID:Expression and localization of matrix-degrading metalloproteinases during colorectal tumorigenesis. 806 80

Although overexpression of the low-affinity p75 neurotrophin receptor (p75NTR) is frequently associated with advanced stages of human melanoma progression, the functional significance of this finding is unknown. We examined whether the degree of cell surface expression of p75NTR in human melanoma cell variants determines their extent of invasion stimulated by nerve growth factor (NGF). Treatment of MeWo melanoma cells or a metastatic spontaneous wheat germ agglutinin-resistant variant subline (70W) of MeWo cells with 2.5S NGF resulted in a dose-dependent enhancement of invasion through a reconstituted basement membrane. This effect was most pronounced with the 70W subline that exhibits brain-metastasizing potential in nude mice but was not found with a poorly metastatic MeWo variant subline (3S5). The expression of p75NTR as determined by Northern blotting and immunoprecipitation analysis of 125I-labeled cell surface proteins correlated with NGF-stimulated invasion. The MeWo melanoma sublines used in this study did not express p140proto-trkA mRNA or any p140proto-trkA variant transcripts including p70trkA as determined by Northern analysis and RT-PCR analysis. Thus, these melanoma cells would not be expected to form functional p75-p140 heterodimers or p140-p140 homodimers capable of transducing an NGF-generated signal to p140proto-trkA cytoplasmic substrates. These cells did express authentic p145trkC transcripts. However, NGF did not catalytically activate p145trkC receptors via increased tyrosine phosphorylation as would be expected if p145trkC participated in the signaling established by NGF. Furthermore, a NGF-stimulated purine-analogue-sensitive kinase activity was found to coimmunoprecipitate with p75NTR. This p75NTR-associated kinase may coordinate initial signaling events evoked by p75NTR ligand interaction. Addition of 2.5S NGF, at concentrations that should saturate cell surface p75NTR, to matrix-adherent cultures of human MeWo and 70W but not 3S5 melanoma cells suppressed the expression of 92-kDa type IV collagenase and stimulated the production of 72-kDa type IV collagenase in its fully active 68-kDa form. In the absence of p140proto-trkA, the matrix-dependent effects of NGF on metalloproteinase expression of brain-metastatic 70W melanoma cells suggest a signaling role for the low-affinity melanoma p75NTR receptor and its associated purine-analogue-sensitive kinase in signaling enhanced matrix penetration of NGF-rich stromal microenvironments such as the brain.
Mol Biol Cell 1993 Nov
PMID:Mediation of NGF-stimulated extracellular matrix invasion by the human melanoma low-affinity p75 neurotrophin receptor: melanoma p75 functions independently of trkA. 830 39

Liarozole fumarate (R85,246), a novel benzimidazole derivative, reduced s.c. and bone metastasis tumor growth by the androgen-independent PC-3ML-B2 human prostatic carcinoma clone in SCID mice. The drug inhibited cell invasion of Matrigel in Boyden chamber chemotactic assays and the secretion of type IV collagenase. In vitro, liarozole failed to inhibit cell proliferation and cell attachment to various substrates (Matrigel, laminin, type IV collagen, and fibronectin). In vivo, the drug also blocked type IV collagenase production in established s.c. tumors. Liarozole has been postulated by others (R. De Coster, W. Wouters, R. Van Ginckel, D. End, et al. J. Steroid Biochem. Mol. Biol., 43: 197-201, 1992) to inhibit retinoic acid catabolism. Our data indicate that liarozole treatment can increase the tumor retinoic acid levels in vivo. Studies of retinoic acid revealed that the drug independently reduced tumor growth in vivo and inhibited cell invasion of Matrigel and the secretion of collagenase IV. Surprisingly, liarozole and retinoic acid failed to exhibit measurable synergistic activity both in vitro and in vivo. Taken together these data suggest that liarozole might inhibit retinoic acid catabolism in vivo and consequently have significant therapeutic value as an anti-prostatic tumor agent.
...
PMID:Liarozole and 13-cis-retinoic acid anti-prostatic tumor activity. 831 15

Tissue inhibitors of metalloproteinases (TIMPs) appear to play an important regulatory role in tissue remodelling and invasion by malignant cells. Since pregnancy involves morphological changes in existing maternal tissues, as well as a strictly controlled invasion by fetal trophoblasts, we have examined the temporal expression of TIMP-1, TIMP-2, and specific metalloproteinases in the mouse uterus, decidua, placenta, amnion, and ovaries throughout gestation by examining mRNA levels on northern and slot blots. Maximal levels of TIMP-1 mRNA were observed from day 6 to day 10 in the uterus, decidua, and placenta. In clear contrast to the early burst of TIMP-1 mRNA accumulation, the level of TIMP-2 mRNA increased steadily throughout gestation in the uterus, decidua, and amnion, while in the placenta it showed a sevenfold increase after day 14. In amnion, TIMP-1 was induced specifically on day 18. Interestingly, the normally high level of TIMP-1 mRNA seen in the ovaries of virgin mice was low during gestation, until day 18 and postpartum, when a sixfold increase over the levels in virgin ovary was observed. In contrast, ovarian TIMP-2 mRNA showed a marginal increase during gestation. The temporal pattern of 72 kDa gelatinase type A followed that of TIMP-2 in the decidua and ovary. Stromelysin-2 mRNA was detected at term only in ovary and decidua. Our data show that the temporal accumulation of TIMP-1 and TIMP-2 mRNA is precisely coordinated in each of the tissue compartments and is independently regulated during the in vivo remodeling of reproductive tissues in gestation.(ABSTRACT TRUNCATED AT 250 WORDS)
Mol Reprod Dev 1993 Jul
PMID:Temporal expression of tissue inhibitors of metalloproteinases in mouse reproductive tissues during gestation. 835 25

The metalloproteinases, a multigene family of metal-requiring enzymes, have been suggested to play a role in tumor invasion and metastasis. Previously, we demonstrated that human primary prostate tumors express higher levels of matrilysin and gelatinase A mRNA than normal prostate does. In the study presented here, we used in situ hybridization and immunohistochemical staining of serial sections of paraffin-embedded primary prostate tumors to compare the sites of matrilysin and gelatinase A expression and protein localization. These results confirmed the epithelial nature of matrilysin expression and protein localization. In contrast, gelatinase A mRNA was localized to the interstitial stroma, whereas the protein was associated with the epithelial tumor cells. In situ hybridization was also used to demonstrate that gelatinase B expression was restricted to macrophages infiltrating the tumors. Proteins isolated from an additional set of frozen tumor specimens were analyzed by western blotting to determine the relative amounts of matrilysin in the active and proenzyme forms. The western analyses demonstrated that in all cases in which matrilysin was detected, at least some of the enzyme was in the active form. These results are discussed with respect to the possible role these enzymes may play in prostate tumor progression.
Mol Carcinog 1996 Jan
PMID:Matrilysin expression in human prostate carcinoma. 856 67


1 2 3 4 5 6 7 8 9 10 Next >>