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)

The levels of expression of various genes were altered in cellular transformants with manipulation of expression of single genes. Vascular endothelial growth factor A (VEGF-A) is a key molecule for tumor progression, although it is unclear how VEGF-A expression regulates various genes. Multiple gene expression levels were evaluated using cDNA arrays in a human hepatocellular carcinoma cell line (HLF) with suppression of the VEGF-A gene by anti-VEGF-A ribozyme (alphaVRz). The ribozyme-mediated suppression of VEGF-A gene solely up-regulated matrix metalloproteinase 1 (MMP1) gene level in HLF/alphaVRz. Levels of expression of other members of MMP family or tissue inhibitors of MMPs did not show any alteration. These results suggested that intracellular suppression of VEGF-A gene was specifically linked to up-regulation of MMP1 in human hepatocellular carcinoma cells.
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PMID:Ribozyme mediated suppression of vascular endothelial growth factor gene expression enhances matrix metalloproteinase 1 expression in a human hepatocellular carcinoma cell line. 1206 53

Matrix metalloproteinases (MMPs) play a key role in cancer progression. Interstitial collagenase (MMP-1) and type IV collagenases (MMP-2, MMP-9) are involved in the initial breakdown of collagen and basement membrane components during tumor growth and invasion. Besides tumor cells, fibroblasts are especially involved in MMP production. The aim of this study was to quantify MMP-1, MMP-2 and MMP-9 within tumor cells and tumor-surrounding fibroblasts compared to normal lung epithelial cells to gain an insight into the function of these MMPs in squamous cell carcinomas of the lung. The expression and activity of MMP-1, MMP-2 and MMP-9 were analyzed in 30 squamous cell carcinomas and in normal lung tissue from the same patients by immunohistology and gelatin zymography. The majority of tumor cells were positive for MMP-1 (mean +/- SD: 67.3 +/- 26.7%) and MMP-9 (64.7 +/- 22.8%), whereas a significantly lower percentage of normal bronchoepithelial cells (47.3 +/- 25.4 and 40.3 +/- 24.2%, respectively; p < 0.01) and fibroblasts located in the tumor-surrounding tissue (39.7 +/- 14.3 and 38.1 +/- 24.1%, respectively; p < 0.01) expressed these MMPs. Only a few tumor cells showed any immunoreactivity for MMP-2 (4.4 +/- 6.7%), whereas a higher percentage of fibroblasts tested positive for this enzyme (8.6 +/- 13.1%; p < 0.01). Using gelatin zymography, we could demonstrate that MMP-2 is activated in the tumor only, not in normal lung tissue. The coordinated expression of MMP-1, MMP-2 and MMP-9 in tumor cells and/or their induction in tumor-surrounding fibroblasts and further activation in the tumor tissue may be involved in the high invasive and metastatic potential of squamous cell carcinomas of the lung. Comparing the results from immunohistology and zymography can give indications for distribution and activity of proteinases, especially certain MMPs such as MMP-2.
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PMID:Differential expression and activity status of MMP-1, MMP-2 and MMP-9 in tumor and stromal cells of squamous cell carcinomas of the lung. 1221 98

Endostatin, a 20-kDa collagen XVIII fragment, inhibits angiogenesis and tumor growth in vivo, but the mechanisms are still unclear. Matrix metalloproteases (MMPs), a family of extracellular and membrane-associated endopeptidases, collectively digest almost all extracellular matrix and basement membrane components, and thus play an important role in tumor progression. We studied the effects of recombinant human endostatin on human MMP-2, -9, -8, and -13. We found that endostatin inhibited the activation and catalytic activity of pro-MMP-9 and -13 as well as recombinant pro-MMP-2. It prevented the fragmentation of pro-MMP-2 that was associated with reduction of catalytic activity. Endostatin had no effect on MMP-8 as shown by collagenase activity assays. An in vitro migration assay and an in vivo chicken chorioallantoic membrane intravasation assay with the human tongue squamous cell carcinoma cell line HSC-3 revealed the biphasic nature of endostatin; low endostatin concentrations inhibited intravasation and migration of these cells in a dose-dependent manner, but at increased concentrations, the inhibitory effect was far less efficient. The results show that endostatin blocks the activation and activities of certain tumor-associated pro-MMPs, such as pro-MMP-2, -9, and -13, which may explain, at least in part, the antitumor effect of endostatin. Our results also suggest that endostatin inhibits tumor progression by directly affecting the tumor cells and not just acting via endothelial cells and blockage of angiogenesis.
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PMID:Endostatin inhibits human tongue carcinoma cell invasion and intravasation and blocks the activation of matrix metalloprotease-2, -9, and -13. 1269 Jan 20

Matrix metalloproteinases (MMPs) that have a proteolytic activity against the components of extracellular matrix (ECM) play an important role in the invasive and metastatic spread of tumors. The role of MMPs and tissue inhibitors of MMPs (TIMPs) in laryngeal squamous cell carcinoma (LSCC) has not been elucidated sufficiently. The aim of the present study was to evaluate the correlation between the expression of collagenase-1 (MMP-1), collagenase-3 (MMP-13) and TIMP-1, as well as the clinicopathological features of LSCCs. The expression of collagenases and TIMP-1 was examined immunohistochemically in 50 cases of surgically obtained specimens of primary LSCCs. Analyses indicated that LSCC cells as well as stromal cells expressed MMP-1, MMP-13 and TIMP-1 immunostaining. Overexpression of TIMP-1 occurred more frequently in non-metastasizing cases (P=0.009). TIMP-1 and MMP-1 staining correlated significantly with the histologic type of LSCC. The keratinizing type of carcinomas exhibited higher TIMP-1 protein expression than the nonkeratinizing variety (P=0.01). TIMP-1 staining was associated with the grade of differentiation, since it was found predominantly in well and moderately differentiated carcinomas (P=0.04). The findings confirm that expression of analyzed MMPs and TIMP-1 is characteristic of LSCC and that these enzymes contribute to the progression of tumors. TIMP-1 upregulation might exhibit lower metastatic potential in LSCCs and is linked rather with an early stage of tumor progression. It seems also that TIMP-1 expression is dependent on the grade of differentiation.
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PMID:Expression of collagenase-1 (MMP-1), collagenase-3 (MMP-13) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in laryngeal squamous cell carcinomas. 1273 32

Pericellular proteolysis plays a pivotal function in cell invasion, a hallmark of tumor growth and metastasis. The minidegradome constituted of two matrix metalloproteinases (MMP), i.e. MMP-2 and MT1-MMP, associated with tissue inhibitor of metalloprotease-2 (TIMP-2) and integrin (alpha(v)beta(3)) or CD(44), is mainly involved in such invasive program. It catalyzes matrix degradation but, alternatively, proteolytic exposure of matricryptic sites or matrikines liberation by those enzymes regulates either positively or negatively tumor cell migration. That applies to types I and IV collagens, elastin, laminin 5, as described here, but such phenomenon might be extended to other matrix macromolecules. The development of tumors from epithelium origin is related to aging. Senescent fibroblasts are characterized by increased expression of MMPs, (particularly collagenase-1 (MMP-1) and stromelysin-1 (MMP-3)) and deposited matrix by those aged cells was shown to favor cancer cell growth. Thus, compositional variation of matrix-surrounding tumor cells, with formation of matricryptic sites and matrikines, can be considered as one main epigenetic factor contributing to tumor progression. A matrix-directed pharmacological approach in cancer is now emerging.
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PMID:Proteolyzed matrix as a template for the regulation of tumor progression. 1288 58

Matrix metalloproteinases (MMPs) have fundamental roles in tumor progression, but most clinical trials with MMP inhibitors have not shown improvements in individuals with cancer. This may be partly because broad-range inhibitors also reduce host-protective antitumor properties of individual MMPs. We generated mice deficient in collagenase-2 (Mmp8), an MMP mainly produced by neutrophils in inflammatory reactions and detected in some malignant tumors. Loss of Mmp8 did not cause abnormalities during embryonic development or in adult mice. Contrary to previous studies with MMP-deficient mice, however, the absence of Mmp8 strongly increased the incidence of skin tumors in male Mmp8(-/-)mice. Female Mmp8(-/-)mice whose ovaries were removed or were treated with tamoxifen were also more susceptible to tumors compared with wild-type mice. Bone marrow transplantation experiments confirmed that Mmp8 supplied by neutrophils was sufficient to restore the natural protection against tumor development mediated by this protease in male mice. Histopathological analysis showed that mutant mice had abnormalities in the inflammatory response induced by carcinogens. Our study identifies a paradoxical protective role for Mmp8 in cancer and provides a genetic model to evaluate the molecular basis of gender differences in cancer susceptibility.
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PMID:Loss of collagenase-2 confers increased skin tumor susceptibility to male mice. 1451 55

Elastin peptides (EPs) produced during cancer progression bind to the elastin binding protein (EBP) found at the surface of dermal fibroblasts, leading to the expression of collagenase-1 gene. The production of this enzyme involved in stromal reaction is caused by the sustained activation of the extracellular signal-regulated kinases 1/2 (ERK1/2) pathway via cAMP/protein kinase A (PKA) and phosphatidylinositol 3-kinase (PI3K). However, the mechanism of these signaling events remains unknown. We show that kappa-elastin (kappaE), a commonly used EP, induces maximum phosphorylation of mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK)1/2 and ERK1/2 after 30 min. The simultaneous inhibition of PKA and PI3K, by N-(2-(p-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide (H89) and 2-(4-morpholynil)-8-phenyl-4H-1-bemzopyran-4-one (LY294002), respectively, blocked MEK1/2 and ERK1/2 phosphorylation, as did lactose, an EBP antagonist. kappaE induced Raf-1 phosphorylation and activation in a PI3K-dependent manner. In our system, the PI3K p110gamma is expressed and activated by betagamma-derived subunits from a pertussis toxin-sensitive G protein after fibroblast stimulation. Pertussis toxin also blocks the Raf-1/MEK1/2/ERK1/2 phosphorylation cascade. In addition, we found that B-Raf is expressed in dermal fibroblasts and activated in a PKA-dependent manner after kappaE treatment, thereby integrating PKA signals to MEK1/2. It is noteworthy that Ras involvement was excluded because ERK1/2 activation by kappaE was not blocked in RasN17-transfected fibroblasts. Together, our results identify a novel Ras-independent ERK1/2 activation system in which p110gamma/Raf-1/MEK1/2 and PKA/B-Raf/MEK1/2 cooperate to activate ERK1/2. Thus, p110gamma and B-Raf seem to be important modulators of dermal fibroblasts physiology and should now qualify as therapeutic targets in strategies aiming at limiting elastin degradation contribution to cancer progression.
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PMID:Elastin peptides activate extracellular signal-regulated kinase 1/2 via a Ras-independent mechanism requiring both p110gamma/Raf-1 and protein kinase A/B-Raf signaling in human skin fibroblasts. 1565 54

Matrix metalloproteinase-8 (MMP-8), also known as collagenase-2 or neutrophil collagenase, was long thought to be expressed solely by maturing neutrophils, and functionally restricted to ECM breakdown. Recent experiments, however, have revealed that this protease can be expressed by a wide variety of cell types and that it plays an important regulatory role in both acute and chronic inflammation. This review intends to give the reader an overview of the most interesting recent findings concerning the role of MMP-8 in inflammation and in cancer progression.
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PMID:Matrix metalloproteinase-8: cleavage can be decisive. 1682 Mar 17

Protease-activated receptors (PARs) are G-protein-coupled receptors (GPCRs) that are activated by a unique proteolytic mechanism. PARs play crucial roles in hemostasis and thrombosis, as well as in inflammation and vascular development. Coagulant proteases, which are generated at sites of vascular injury, act mainly through PARs to elicit signalling in a variety of cell types. Since PARs are irreversibly activated signalling must be tightly regulated. Desensitization and trafficking of proteolytically activated PARs control the magnitude, duration and spatial aspects of receptor signalling. Recent studies have revealed novel endocytic sorting mechanisms that regulate PAR signalling. PARs have also been implicated in tumor progression. PARs are overexpressed in several types of malignant cancer, transmit signals in response to tumor-generated proteases and promote tumor growth, invasion and metastasis. Recent work also indicates that matrix metalloprotease 1 (MMP-1) signals through PAR1 to promote tumor growth and invasion. In addition to PAR overexpression, tumor cells display aberrant PAR1 trafficking, which causes persistent signalling and cellular invasion. Thus, a novel type of gain-of-function in GPCR signalling in cancer can be acquired through dysregulation of receptor trafficking.
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PMID:Protease-activated receptor signalling, endocytic sorting and dysregulation in cancer. 1734 29

Tumor cell invasion through basement membranes and into stromal tissue are key steps for promoting growth and metastasis. Tumor cells express various extracellular-matrix-degrading enzymes such as matrix metalloproteinases (MMPs) to degrade extracellular matrix components to facilitate tumor migration and invasion. Histological and clinical studies suggest a role for MMP-1 (collagenase-1) in malignant melanoma invasion. In this study, we evaluated MMP-1 in regulating malignant phenotypes of human melanoma cells by generating human melanoma cells stably transfected with pro-MMP-1 cDNA. The transfectants expressed the active form of MMP-1 associated with cells and showed enhanced invasive and growth abilities in type I collagen gel. Furthermore, MMP-1 expression promoted anchorage-independent growth, which was inhibited in the presence of type II transforming growth factor (TGF)-beta receptor:Fc fusion protein that scavenges TGF-beta receptors. Finally, we demonstrated that MMP-1 directly generated active TGF-beta from its latent form. Thus, these results suggest that MMP-1 produced from melanoma cells would play a role in tumor progression by both degrading matrix proteins and generating active growth factors such as TGF-beta in vivo.
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PMID:Expression of collagenase-1 (MMP-1) promotes melanoma growth through the generation of active transforming growth factor-beta. 1762 50


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