Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have transfected a full-lenght cDNA-encoding human tissue inhibitor of metalloproteinases-1 (TIMP-1) by lipofection in highly invasive F3II mouse mammary sarcomatoid carcinoma cells. In vitro, overexpression of TIMP-1 was associated with abrogation of metalloproteinase activity, extended doubling time, and a more flattened, epithelioid polyhedric morphology. Female Balb/c mice inoculated subcutaneously with TIMP-1 transfectant exhibited a prolonged tumor latency and tumor burden was significantly lower in early stages of tumor growth. Control F3II cells grew by invading the muscular and adipose layers of the subcutis, dermis, and dermal papillae. On the contrary, mammary carcinoma cells transfected with TIMP-1 grew without signs of active invasion of dermis. Tumors also revealed a decreased amount of necrosis and host inflammatory cell infiltrates. However, histological analysis did not demonstrate any change in vascular density. Animals bearing F3II tumors overexpressing TIMP-1 showed a significant reduction in the size of metastatic lung nodules. These data suggested that TIMP-1 overexpression may reduce local invasion and delay the progression of the metastatic disease in the present mammary tumor model.
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PMID:Histopathological findings in a highly invasive mouse mammary carcinoma transfected with human tissue inhibitor of metalloproteinases-1. 968 13

Tissue inhibitor of metalloproteinase (TIMP) inhibits the proteolytic activity of several matrix metalloproteinases centrally involved in tumor invasion and metastases. The purpose of this study was to determine the origin of TIMP-1 mRNA production in both human colorectal cancer (CRC) and metastatic liver lesions as well as define the relationships between TIMP-1 RNA expression and standard clinicopathological variables of CRC. Total cellular RNA, extracted from 56 CRC and 10 liver metastases, were examined by Northern blot hybridization. The mean/normal mucosa fold increase of TIMP-1 RNA was significantly elevated in both CRC (12.1 +/- 1.7) and liver metastases (10.0 +/- 3.6). No relationship was noted between TIMP-1 expression and tumor size, location nor differentiation. Based on lymph node metastases status, significantly higher TIMP-1 RNA levels were found in CRC with metastases than in those without metastases (15.6 +/- 3.3 versus 7.9 +/- 1.3) (P = 0.04). Similarly, TIMP-1 RNA levels were higher in primary CRC with distant metastases than those without distant metastases (17.6 +/- 4.1 versus 9.3 +/- 1.9) (P = 0. 04). In situ hybridization localized TIMP-1 mRNA predominantly in tumor stroma within spindle fibroblast-like cells rather than in cancer cells themselves. The correlation between the increased TIMP-1 mRNA level and advanced CRC stage noted in this study reflects a possible growth-promoting function for TIMP-1 in human CRC.
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PMID:Elevated tissue inhibitor of metalloproteinase 1 RNA in colorectal cancer stroma correlates with lymph node and distant metastases. 981 60

Breast cancer cell lines vary in invasive behavior and one highly invasive cell line (MDA-MB-231) proteolytically degrades extracellular matrix with invadopodia (Thompson et al. 1992, J Cell Physiol, 150, 534-44; Chen et al 1994, Breast Cancer Res Treat, 31, 217-26). Invadopodial proteolysis of extracellular matrix is thought to be necessary for invasion; however, this has not been demonstrated directly. To obtain such evidence, normal (HBL-100) and malignant (MCF-7, MDA-MB-231) breast cells were evaluated for invadopodial proteolysis of extracellular matrix and invasive behavior. We report that invadopodial proteolysis of immobilized fibronectin is positively correlated with invasion of cells into type I collagen gels. Moreover, reducing the proteolytic activity of invadopodia with the metalloproteinase inhibitor, batimastat (BB-94), also decreases invasion indicating that breast cancer cell invasion is dependent upon proteolytically active invadopodia.
Clin Exp Metastasis 1998 Aug
PMID:Proteolysis of extracellular matrix by invadopodia facilitates human breast cancer cell invasion and is mediated by matrix metalloproteinases. 987 98

Pentoxifylline (PTX), a methylxanthine derivative widely used as a hemorheological agent in the treatment of peripheral vascular disease, was studied to unveil the mechanisms responsible for its inhibitory action on B16-F10 experimental metastasis. In vitro pretreatment of B16-F10 cells with noncytotoxic concentrations of PTX significantly inhibited their adhesion to reconstituted basement membrane Matrigel(R) and type IV collagen as well as the relative activity of secreted 92 kD metalloproteinase. However, PTX pretreatment of B16-F10 cells did not affect their in vitro invasiveness. Heterotypic organ adhesion assays carried out with B16-F10 cells and suspended organ tissues demonstrated that pretreatment with noncytotoxic concentrations of PTX of both, tumor cells or lung tissue, brought about a dose-dependent inhibition of melanoma cell adhesion to lung. Immunohistochemical studies using antibodies against CD31 adhesion molecule (PECAM-1) revealed that B16-F10 cells adhere to lung endothelial cells. Our results suggest that PTX may exert its inhibitory effect on tumor lodgment, and as a consequence of that on experimental metastases, through an inhibitory action on cell adhesion molecules.
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PMID:Studies on the mechanisms responsible for inhibition of experimental metastasis of B16-F10 murine melanoma by pentoxifylline. 1008 44

Preclinical in vivo studies of agents targeted against metastasis have to date been based primarily on end-point assays. Such assays can determine whether a treatment affects the number or size of metastases in an organ at a given time, but are poorly suited to determining how and at what stage in the process the treatment affected the end point. High resolution in vivo videomicroscopy permits direct observation of the process of metastasis as it occurs in living animals over time. Studies based on this technique and a cell accounting procedure we have devised, have shown that early steps in the metastatic process (survival in the circulation, extravasation) contribute relatively little to cell loss and metastatic inefficiency. Steps that occur after extravasation appear to be primarily responsible for the significant losses that result in metastatic inefficiency, and these steps may represent good targets for the design of new antimetastatic therapies. Matrix metalloproteinases have been implicated functionally in metastasis, and are viewed as an appropriate target in the development of inhibitors of metastasis. Using both endogenous and synthetic exogenous metalloproteinase inhibitors, we have shown that the inhibition of metastasis which these agents produce is not due to inhibition of cell extravasation from the circulation into the tissue, but to reduction of angiogenesis within metastases. A similar conclusion was reached concerning the mechanism of action, on metastasis, of carboxyamidotriazole, an inhibitor of calcium-mediated signal transduction which is currently in Phase II single agent clinical trials. In vivo videomicroscopy of sequential steps in metastasis, coupled with methods that allow precise quantification of cell loss at specific steps in the metastatic process, as well as standard histological assessment at stages identified as crucial, allow characterization of the details of metastasis as an ongoing process. This provides a powerful complement to end-point assays, for it allows mechanistic information to be obtained from in vivo experiments, an approach which provides better understanding of how and when a drug may function in vivo to inhibit metastasis.
Cancer Metastasis Rev
PMID:Preclinical assessment of anti-cancer therapeutic strategies using in vivo videomicroscopy. 1035 79

We previously found that 12-O-tetradecanoylphorbol-13-acetate (TPA)-enhanced invasiveness was associated with augmentation of cell motility but not that of metalloproteinase activity in a highly metastatic variant (L-10) of the human colon adenocarcinoma cell line RCM-1 and that this enhancement was possibly mediated by protein kinase C (PKC). In this study, we first intended to determine the specific isoforms of PKC involved in this TPA-enhanced L-10 cell motility that leads to invasion, and then investigated the way to inhibit the enhanced motility and invasion by using antisense oligodeoxynucleotides (ODN) targeting the isoform. An activator of conventional PKC isoforms (cPKC), thymeleatoxin, enhanced L-10 cell motility and invasion like TPA, and an inhibitor of cPKC, Go-6976, efficiently inhibited TPA-enhanced motility and invasion. TPA treatment induced a shift of PKC-alpha, but not other isoforms, from the cytosol to the membrane fraction, indicating the activation of the isoform. During the assay period, only activation but not downregulation of PKC-alpha occurred with the low concentration of TPA used in our assays. Antisense ODNs specific for PKC-alpha efficiently reduced its expression at the protein levels and inhibited L-10 cell motility in the absence of TPA. With TPA treatment, however, the remaining PKC-alpha was sufficient for activation leading to enhanced invasion. Only a combination of depletion of PKC by prolonged stimulation with a high concentration of phorbol 12,13 dibutyrate (PDBu) and treatment with antisense ODNs effectively inhibited L-10 cell invasion even in the presence of TPA. These results suggested that downregulation of PKC isoforms by treatment with antisense ODNs alone is insufficient to suppress the isoform-mediated cellular events in the presence of PKC activators, and thus that some additional treatments are necessary for the successful downregulation of them.
Clin Exp Metastasis 1999 Jun
PMID:TPA-enhanced motility and invasion in a highly metastatic variant (L-10) of human rectal adenocarcinoma cell line RCM-1: selective role of PKC-alpha and its inhibition by a combination of PDBu-induced PKC downregulation and antisense oligonucleotides treatment. 1054 22

Most preclinical studies of tumour metastasis and effects of molecular interventions have been based on end point assays, and little is known about the fate of cells at sequential steps in the metastatic process. In vivo videomicroscopy permits direct observations of sequential steps in hematogenous metastasis as they occur in living animals over time. These steps include initial arrest of cells in the microcirculation, extravasation, postextravasation migration and growth in the target organ. In the mouse liver model, cells are arrested in periportal sinusoids based on size restriction, survive in the circulation and extravasate into the tissue by 48 to 72 h regardless of metastatic potential. Thereafter, cells may migrate to preferred sites for growth. Critical steps responsible for cell losses and metastatic inefficiency occur at the level of postextravasation cell growth. Many extravasated cells may remain dormant, and growth to form micrometastases is initiated in only a small subset of cells. Most early micrometastases may disappear after a few days, and only a small subset continue growth into macroscopic tumours. Angiogenesis is a prerequisite for continued growth of metastases, as shown previously by others. Integrin based interventions can modulate postextravasation cell migration and cell growth. Matrix metalloproteinase inhibitors can inhibit tumour angiogenesis and thus reduce growth. Key targets against which future therapeutic strategies should be directed include the initiation and maintenance of growth of micrometastases, and the activation of dormant solitary cells.
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PMID:Tumour metastasis to the liver, and the roles of proteinases and adhesion molecules: new concepts from in vivo videomicroscopy. 1063 26

Bone metastases are often associated with osteolysis and subsequent pathological fractures. To determine if metastatic human cancer cells can directly degrade non-mineralized and mineralized bone, we used prostate PC3 adenocarcinoma cell lines, which were originally established from skeletal metastases. We show that PC3 cells and their conditioned medium degraded non-mineralized, osteoid-like radiolabelled extracellular matrices from human Saos2 and U2OS osteoblast-like cells. These cells also directly degraded mineralized bone by inducing (45)Ca release from rat fetal calvariae and forming resorption pits on bone slices, an effect increased by transforming growth factor-beta(1). A role for matrix metalloproteinases in degradation was shown by: (1) stimulation by the phorbol ester TPA of PC3-induced matrix degradation and release of matrix metalloproteinase activity; (2) abrogation of matrix degradation by 1,10-phenanthroline, a metalloproteinase inhibitor, and (3) degradation of purified type I collagen by PC3 cells and their conditioned medium. We demonstrate that human prostate cancer cells can directly degrade bone-related matrices and that matrix metalloproteinases have a role in this process.
Invasion Metastasis
PMID:Human metastatic prostate PC3 cell lines degrade bone using matrix metalloproteinases. 1072 74

We investigated whether the expression of membrane-type-1 matrix metalloproteinase (MT1-MMP), matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) was consistent with the proposed roles of these proteins in promoting metastasis in colorectal cancer. The expression of MT1-MMP was significantly more frequent in deeply invasive carcinomas (P = 0.007) and in cases of vascular invasion (P = 0.02). The frequency of detection of MMP-2 in the stroma was much greater in vascular invasion-positive cases (42%) than in negative cases (20%; P = 0.02). The rate of detection of TIMP-2 in tumour cell cytoplasm increased with the depth of invasion (P = 0.03). TIMP-2 in the stroma was found more frequently in tumours with lymphatic invasion and lymph node metastasis (P < 0.05). Significant correlations were found between detection of MT1-MMP and MMP-2 in tumour cell cytoplasm (P < 0.05), of MT1-MMP and TIMP-2 in tumour cell cytoplasm (P < 0.01), and of MMP-2 and TIMP-2 in tumour cell cytoplasm (P < 0.01). Immunohistochemical detection of MT1-MMP and TIMP-2 might be useful for monitoring infiltration in colorectal carcinoma but is not correlated with distant metastases.
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PMID:Immunohistochemical detection of membrane-type-1-matrix metalloproteinase in colorectal carcinoma. 1090 73

Infiltrative capacity was found to distinguish separate T leukemia cell lines. Of seven T-cell lines four exhibited capacity to infiltrate Matrigel. Analysis of infiltration was performed at the single-cell level throughout the Matrigel using a depth meter. Further, we examined differences in migration capacity and metalloproteinase production between infiltrating and non-infiltrating T-cell lines. The capacity to infiltrate was not directly correlated to the capacity to adhere to the Matrigel or to migrate on/to extracellular matrix components. It is concluded that infiltration capacity does not simply reflect capacity to migrate but represents a distinct functional property. The production of metalloproteinases and their inhibitors by the separate T-cell lines was analyzed using rt PCR, biosynthetic labelling, zymography, immunoprecipitation and ELISA. All T-cell lines with capacity to infiltrate produced matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) while non-infiltrating cell lines did not express MMP-9. Expression of MMP-1, 2, 3, 10, 14 and 17 showed no correlation to capacity to infiltrate. Analysis of infiltration in the presence of a metalloprotease inhibitor showed an increased number of cells within the gel. This enhancement of infiltration suggests that the function of MMPs and/or their inhibitors in lymphocyte infiltration is more complex than previously thought.
Clin Exp Metastasis 1999
PMID:Infiltrative capacity of T leukemia cell lines: a distinct functional property coupled to expression of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinases-1 (TIMP-1). 1091 15


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