Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

For at least 30 years, matrix metalloproteinases (MMPs) have been heralded as promising targets for cancer therapy on the basis of their massive up-regulation in malignant tissues and their unique ability to degrade all components of the extracellular matrix. Preclinical studies testing the efficacy of MMP suppression in tumor models were so compelling that synthetic metalloproteinase inhibitors (MPIs) were rapidly developed and routed into human clinical trials. The results of these trials have been disappointing. Here we review the studies that brought MPIs into clinical testing and discuss the design and outcome of the trials in light of new information about the cellular source, substrates, and mode of action of MMPs at different stages of tumor progression. The important lessons learned from the MPI experience may be of great value for future studies of MPIs and for cancer drug development in general.
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PMID:Matrix metalloproteinase inhibitors and cancer: trials and tribulations. 1192 19

Advanced stage neuroblastomas (NB) exhibit a tissue inhibitor of metalloproteinase (TIMP)-2/matrix metalloproteinase (MMP) imbalance, considered a prerequisite for MMP involvement in tumor progression in vivo. Human SH-SY5Y NB cells exhibit a similar TIMP-2/MMP imbalance that promotes in vitro invasive behavior that is inhibited by exogenous TIMP-2. The DNA methyltransferase inhibitor 5-azacytidine (5-AzaC) redresses this TIMP-2/MMP imbalance, reconstituting TIMP-2 expression, without effecting that of MMP-2, by stimulating TIMP-2 transcription and inhibiting in vitro invasivity of SH-SY5Y cells. 5-AzaC stimulated transcription from a nonmethylated TIMP-2 promoter reporter gene construct consistent with regulation of a TIMP-2 transactivator. Promoter deletion and point-mutation analysis localized this effect to an inverted CCAAT element at position -73. This element bound specific complexes containing NF-YA and NF-YB proteins in SH-SY5Y nuclear extracts, the binding of which was augmented by 5-AzaC in association with enhanced levels of NF-YB protein and the function of which was confirmed by inhibition using dominant-negative NF-YA. The data highlight a novel indirect methylation-mediated mechanism for regulating the TIMP/MMP equilibrium in NB cells, involving repression of TIMP-2 relative to MMP-2 expression, dependent upon suboptimal NF-Y transcription factor function, which can be reversed by methyltransferase inhibition.
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PMID:Reconstitution of TIMP-2 expression in SH-SY5Y neuroblastoma cells by 5-azacytidine is mediated transcriptionally by NF-Y through an inverted CCAAT site. 1274 50

Neovascularization is a hallmark of cancer progression. Suppression of the angiogenic response in tumors has been associated with inhibition and even regression of total tumor mass. Therefore, the derivation of synthetic or natural products that could interfere with proangiogenic signaling pathways can greatly impact cancer therapy. Using the antiangiogenic motifs in thrombospondin-1, we have recently cloned METH1/ADAMTS1, a secreted metalloproteinase with three thrombospondin-1, and shown that the protein inhibits endothelial cell proliferation in vitro and blocks the neovascular response induced by growth factors in vivo. The mechanism of action responsible for these events has not been elucidated. In this report, we present evidence to support two effects of METH1/ADAMTS1 that impact proangiogenic signaling events. ADAMTS1 binds to VEGF and dampens VEGFR2 phosphorylation. The ability of ADAMTS1 to bind VEGF and functionally inactivate VEGFR2 is reversible as dissociation of the complex results in active growth factor. A second activity of ADAMTS1 requires the catalytic domain as a single point mutation in the metalloproteinase domain renders the protein inactive in tumor xenograft assays. The emerging theme is that both domains are likely required for the antiangiogenic/antitumor activities of ADAMTS1.
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PMID:ADAMTS1: a matrix metalloprotease with angioinhibitory properties. 1281 50

To investigate the roles of matrix metalloproteinases (MMPs) in thymic epithelial tumors, we examined the expression of MMP-2, -7, and -9; membrane-type 1 (MT1)-MMP; and tissue inhibitor of metalloproteinase-2 (TIMP-2) in 57 tumors by immunohistochemistry and in selected 15 cases by in situ hybridization. The tumors consisted of 5 type A, 12 type AB, 11 type B1, 11 type B2, 9 type B3, and 9 type C thymomas according to the World Health Organization histologic classification system and of 22 stage I, 13 stage II, 8 stage III, and 14 stage IV thymomas according to the Masaoka staging system. In the positive cases, MMPs and TIMP-2 were expressed in both tumor cells and stromal cells. The cellular localization of MMPs detected by immunohistochemistry was almost identical with that of the mRNA signals detected by in situ hybridization. MMP-2 and MMP-7 were predominantly expressed in type B3 thymoma and type C thymoma, respectively. Expression of MT1-MMP and TIMP-2 correlated with that of MMP-2, indicating a proteolytic activation of the latter. MMP-9 was prominent in type B2 thymoma. Expression in tumor cells of MMP-2 or MMP-7 was also correlated with clinical stage. The present study suggests that certain MMPs may play an important role in the tumor progression of different subtypes of thymic epithelial tumors and that MMP-2 and MMP-7 may contribute to the tumor aggressiveness and malignant potential.
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PMID:Expression of matrix metalloproteinases 2 and 7 in tumor cells correlates with the World Health Organization classification subtype and clinical stage of thymic epithelial tumors. 1469 10

Tissue inhibitors of metalloproteinases (TIMPs) are a family of multifunctional proteins known to possess a broad range of biological activities, including inhibition of metalloproteinase activity, regulation of proliferation and apoptosis of a variety of cell types, and, depending on the context, differential regulation of angiogenic and inflammatory responses. Elevated mRNA expression of TIMP family members correlates with malignancy and clinical outcome in many human cancer types; however, a protective role for TIMPs also has been observed in various mouse models of human cancer. In the current study, we found distinct spatial-temporal expression patterns for the mRNA of TIMP family members in a mouse model of epithelial carcinogenesis [i.e., keratin 14-human papillomavirus 16 (K14-HPV16) transgenic mice]. To test the hypothesis that elevated expression of TIMP-1 functionally regulates epithelial carcinogenesis, we introduced a human TIMP-1 transgene into K14-HPV16 transgenic mice and assessed neoplastic progression. Results from these studies suggest that TIMP-1 enhances tumorgenicity by potentiating keratinocyte hyperproliferation and appearance of chromosomal aberrations in premalignant cells, thereby increasing their risk to undergo malignant conversion. In addition, TIMP-1 inhibits tissue gelatinolytic activity in tumor stroma, affects stabilization of collagen fibrils, but does not inhibit malignant conversion of dysplasias into carcinomas or development of metastases. The combined implications of these studies suggest that TIMP-1 is an important contributor to epithelial neoplastic progression and supports the concept that TIMP-1 exerts differential regulation on tissues in a stage-dependent manner.
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PMID:TIMP-1 alters susceptibility to carcinogenesis. 1487 25

Membrane type-I metalloproteinase (MT1-MMP) is a transmembrane metalloproteinase that is critical for tumor cell invasion. MT1-MMP can degrade extracellular matrix (ECM) proteins directly and/or indirectly by activating soluble MMPs such as pro-MMP-2. Although MT1-MMP is upregulated in malignant melanoma, the biological consequences of elevated MT1-MMP expression for tumor progression are not entirely understood. In the current study, we have utilized the Bowes melanoma line for evaluating MT1-MMP in invasion and growth. Our studies extend the earlier observations to demonstrate that MT1-MMP expression in Bowes melanoma cells promotes selective invasion into matrigel but not matrices consisting of type-I collagen. Furthermore, MT1-MMP expressing melanoma cells exhibit increased migration in response to laminin 1 but not to type-I or type-IV collagen. MT1-MMP expression results in enhanced 3 dimensional growth in agarose gels and in long-term cultures within matrigel. The hydroxymate inhibitor BB94 inhibits MT1-MMP enhanced invasion and growth in 3 dimensional culture systems, but had no effect on increased motility. We demonstrated that MT1-MMP expression significantly facilitated tumorigenicity and growth by intradermal injection. The results suggest a more general role for elevated MT1-MMP in promoting both the selective invasion and increased growth of malignant melanoma in vivo.
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PMID:Membrane type-1 matrix metalloproteinase promotes human melanoma invasion and growth. 1496 5

Matrix metalloproteinase (MMP)-3 (stromelysin-1) degrades various components of the extracellular matrix as well as several non-matrix components; it has notably been shown to activate other MMPs relevant to cancer and metastasis, including MMP-9. MMP-3 gene expression in the tumor microenvironment could therefore contribute to cancer progression. Transcriptional regulation of MMP genes was often described to occur upon intercellular interactions, leading to overexpression of these genes by cancer and/or stromal cells. In the present work, we report that expression of MMP-3 in T lymphoma cells is transiently induced during specific intercellular contact with endothelial cells (EC). Moreover, mice injected with lymphoma cells expressing MMP-3 constitutively developed thymic lymphoma more rapidly than those injected with control lymphoma cells. We also found that overexpression of MMP-3 in lymphoma transfectants significantly improved their ability to migrate through the matrix when compared to cells transfected with the control vector. These results provide the first in vivo evidence that local expression of MMP-3 promotes lymphoma progression and indicate that MMP-3 expression is tightly regulated upon lymphoma cell/stromal cell interaction.
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PMID:Stromelysin-1 (MMP-3) is inducible in T lymphoma cells and accelerates the growth of lymphoid tumors in vivo. 1498 95

Matrix metalloproteinase 19 (MMP-19) is a member of the MMP family of endopeptidases that, in contrast to most MMPs, is widely expressed in human tissues under normal quiescent conditions. MMP-19 has been found to be associated with ovulation and angiogenic processes and is deregulated in diverse pathological conditions such as rheumatoid arthritis and cancer. To gain further insights into the in vivo functions of this protease, we have generated mutant mice deficient in Mmp19. These mice are viable and fertile and do not display any obvious abnormalities. However, Mmp19-null mice develop a diet-induced obesity due to adipocyte hypertrophy and exhibit decreased susceptibility to skin tumors induced by chemical carcinogens. Based on these results, we suggest that this enzyme plays an in vivo role in some of the tissue remodeling events associated with adipogenesis, as well as in pathological processes such as tumor progression.
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PMID:Diet-induced obesity and reduced skin cancer susceptibility in matrix metalloproteinase 19-deficient mice. 1516 94

Exposure to cigarette smoke (CS) can lead to the development of lung cancer, but the molecular mechanisms underlying this process remain unclear. Given that activator protein 1 (AP-1) regulates genes involved in both physiologic and pathophysiologic processes, we have investigated the effects of CS on Jun and Fos family member expression and regulation using a nonmalignant human bronchial epithelial cell line, 1HAEo. Exposure to CS caused a marked upregulation of c-Jun, c-Fos, and Fra-1, but not of Fra-2, Jun-B, and Jun-D expression. Because Fra-1 is overexpressed in various tumors and upregulates genes associated with tumor progression, we further elucidated the mechanisms that control CS-stimulated fra-1 induction. CS stimulated fra-1 induction primarily at the transcriptional level. However, epidermal growth factor receptor (EGFR)-specific inhibitor, AG1478, completely suppressed CS-stimulated fra-1 expression. Similarly, the specific inhibitors of extracellular signal-regulated kinase (ERK), c-Jun NH2 terminal kinase (JNK), and p38 kinase signaling markedly suppressed fra-1 induction. Consistent with this finding, AG1478 blocked CS-stimulated ERK, JNK, and p38 phosphorylation. These results suggest that EGFR-activated multiple kinase signaling is essential for fra-1 induction. Furthermore, treatment of cells with GM6001, which inhibits matrix metalloproteinase activity, significantly suppressed CS-stimulated EGF shedding, EGFR and ERK kinase phosphorylation, and subsequent fra-1 induction. Collectively, our findings indicate an obligatory role for metalloproteinase-EGFR-mediated mitogen-activated protein kinase signaling in controlling CS-induced fra-1 expression.
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PMID:Matrix metalloproteinase/epidermal growth factor receptor/mitogen-activated protein kinase signaling regulate fra-1 induction by cigarette smoke in lung epithelial cells. 1552 91

In this paper, we investigated whether protein kinase C-zeta (PKC zeta), a member of the atypical PKC family, induces phenotypic alterations associated with malignant transformation and tumor progression in mammary cells. The stable overexpression of PKC zeta in immortalized mammary epithelial cells (NMuMG), activates the mitogenic extracellular signal-regulated kinase (ERK) pathway, enhanced clonal cell growth and exerts profound effects on proteases secretion. The effect on proteases expression seems to be specific for urokinase-type plasminogen activator and metalloproteinase-9 (MMP-9) because no modulation in MMP-2 and MMP-3 production could be detected. In addition, our experiments demonstrated that PKC zeta overexpression markedly altered the adhesive, spreading, and migratory abilities of NMuMG cells. The overexpression of this enzyme was not sufficient to confer an anchorage-independent growth capacity. An extensive mutational analysis of PKC zeta revealed that the effects observed in NMuMG cells were strictly dependent on the kinase (catalytic) domain of the enzyme. Taken together, these results suggest that in mammary cells PKC zeta modulates several of the critical events involved in tumor development and dissemination through the activation of mitogen activated protein kinase (MAPK)/ERK pathway.
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PMID:Atypical protein kinase C-zeta modulates clonogenicity, motility, and secretion of proteolytic enzymes in murine mammary cells. 1554 34


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