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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The brain is a unique microenvironment enclosed by the skull, lacking lymphatic drainage and maintaining a highly regulated vascular transport barrier. To metastasize to the brain malignant tumor cells must attach to microvessel endothelial cells, respond to brain-derived invasion factors, invade the blood-brain barrier and respond to survival and growth factors. Trophic factors are important in brain invasion because they can act to stimulate this process. In responsive malignant cells trophic factors such as neurotrophins can promote invasion by enhancing the production of basement membrane-degradative enzymes (such as type IV collagenase/gelatinase and heparanase) capable of locally destroying the basement membrane and the blood-brain barrier. We examined human melanoma cell lines that exhibit varying abilities to form brain metastases. These melanoma lines express low-affinity neurotrophin receptor p75NTR in relation to their brain-metastatic potentials but the variants do not express trkA, the gene encoding a high affinity nerve growth factor (NGF) tyrosine kinase receptor p140trkA. Melanoma cells metastatic to brain also respond to paracrine factors made by brain cells. We have found that a paracrine form of transferrin is important in brain metastasis, and brain-metastatic cells respond to low levels of transferrin and express high levels of transferrin receptors. Brain-metastatic tumor cells can also produce autocrine factors and inhibitors that influence their growth, invasion and survival in the brain. We found that brain-metastatic melanoma cells synthesize transcripts for the following autocrine growth factors: TGF beta, bFGF, TGF alpha and IL-1 beta. Synthesis of these factors may influence the production of neurotrophins by adjacent brain cells, such as oligodendrocytes and astrocytes. Increased amounts of NGF were found in tumor-adjacent tissues at the invasion front of human melanoma tumors in brain biopsies. Trophic factors, autocrine growth factors, paracrine growth factors and other factors may determine whether metastatic cells can successfully invade, colonize and grow in the central nervous system.
Clin Exp Metastasis 1995 Mar
PMID:The role of trophic factors and autocrine/paracrine growth factors in brain metastasis. 788 17

The 72-kDa (MMP-2, gelatinase A) and the 92-kDa (MMP-9, gelatinase B) matrix metalloproteinases have been associated with tumor cell invasion and metastasis. Immunohistological staining of MMP-2 and MMP-9, basal lamina collagen IV and TIMP-2 were performed on frozen sections of 83 invasive breast carcinomas. MMP-2 and MMP-9 were associated with neoplastic cell plasma membrane in 72% of cases and exhibited inter-tumoral variability of staining intensity. MMP-2 and MMP-9 staining was not correlated with presence of metastases at time of diagnosis or with disease outcome. TIMP-2 was detected in the peri-tumoral stroma and was present in 87% of cases. Residual benign breast tissue was negative for TIMP-2 staining. Neoplasms with diffuse TIMP-2 staining (24%) recurred significantly more frequently (75% recurred) than cases with focal (42% recurred) or absent (27% recurred) TIMP-2. Presence of collagen IV was negatively correlated with gelatinase staining. We conclude that up-regulation of MMP-2 and MMP-9 expression in breast tumor cells is reciprocally correlated to collagen IV staining. Clinical outcome, however, is more closely related to the presence of TIMP-2 than the corresponding MMPs. Enhanced TIMP-2 expression, therefore, may denote a stromal response to tumor invasion, indicative of aggressive behavior in a subset of breast carcinomas.
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PMID:Enhanced expression of tissue inhibitor of metalloproteinase-2 (TIMP-2) in the stroma of breast carcinomas correlates with tumor recurrence. 792 38

The purpose of the study was to compare the effects of dietary linoleic acid (LA) intake on the growth and metastasis of MDA-MB-435 and MDA-MB-231 human breast cancer cells in nude mice, together with their invasive capacity and secretion of type IV collagenase (gelatinase) in vitro. Each tumor cell line (10(6) cells) was injected into a right-sided mammary fat pad in 60 mice with equal numbers (30 mice/group) assigned to isocaloric diets containing 23% (w/w) total fat and 2% or 12% (w/w) LA. The MDA-MB-435-cell mammary fat pad tumors became palpable earlier and initially they grew more rapidly, but by 6 weeks the MDA-MB-231-cell tumors exhibited an acceleration of growth which was enhanced by the high-LA diet. At necropsy, 12 weeks after the tumor cell injections, the mean weight [10.2 +/- 1.4 g(SEM)] of mammary fat pad MDA-MB-231 cell tumors in 12% LA-fed mice was significantly higher (6.7 +/- 1.4 g) than that of the mice fed 2% LA; also, it was higher than that of MDA-MB-435 cell tumors in the 12% LA-fed mice (3.6 +/- 0.1 g) or the 2% LA-fed mice (3.3 +/- 0.1 g) (each P < 0.001). Mice fed the 12% LA diet had a higher incidence of grossly visible MDA-MB-435 cell pulmonary metastatic nodules than those fed the 2% LA diet (67% versus 33%; P < 0.02), more metastatic lesions (5.7 +/- 1.6 versus 2.3 +/- 0.8; P < 0.05), and greater total volumes (62.0 +/- 25.9 versus 24.8 +/- 9.0 mm3; P < 0.02) per mouse. Of the MDA-MB-231 cell tumor-bearing mice, only 1 in the 12% LA dietary group and 2 in the 2% LA dietary group had macroscopic nodules but the incidence of microscopic metastases was 68 and 42%, respectively. The MDA-MB-231 cell line exhibited a relatively high capacity for invasion in vitro and constitutively high levels of both total type IV collagenolytic activity and M(r) 92,000 gelatinase production which were unaffected by LA. In contrast, MDA-MB-435 cells had approximately only one-sixth the invasive capacity and secreted a relatively low level of type IV collagenase and little of the M(r) 92,000 gelatinase; both invasion and enzyme production were stimulated by LA.
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PMID:Effects of linoleic acid on the growth and metastasis of two human breast cancer cell lines in nude mice and the invasive capacity of these cell lines in vitro. 798 56

Metalloproteinases, inhibitors of metalloproteinases, plasminogen activators, inhibitors of plasminogen activators and cathepsins are thought to be involved in invasion by tumor cells. Glioblastoma multiforme is highly malignant and extremely refractory to therapy. One reason is because of its highly invasive nature within the nervous system. However, it remains unclear how invasion/dissemination of glioblastoma multiforme proceeds. In this study, we attempted to determine which proteinases were responsible for the invasion activity of human glioma cell lines in vitro. Nine human glioma cell lines (NHG1, NHG2, IN157, IN301, IN500, U251, U343, T98G and CCF-STTG1) derived from patients with glioma were grown in culture and used. We compared the invasion activity of glioma cell lines in a Matrigel invasion assay system, and formulated the activity as invasion index (%). Among the nine cell lines, IN157, IN500 and U343 showed less than 10% invasion activity (low group); NHGI, IN301 and CCF-STTG1 showed 10-25% activity (intermediate group); NHG2, U251 and T98G showed more than 30% activity (high group). Addition of an inhibitor of metalloproteinases, TIMP-1, to the assay system was found to significantly inhibit invasion activity of T98G cells (P < 0.01). Northern blot analysis demonstrated expression of urokinase-type plasminogen activator (uPA), tissue-type PA (tPA) and PA inhibitor-1 (PAI-1) in some of the above cell lines. Cellular levels of PAs and their inhibitor mRNA, however, appeared not to be correlated with invasion activity in most glioma cell lines except for CCF-STTG1. Expression of 72 kDa type IV collagenase (MMP-2) was much lower in IN157, IN500 and U343 than other cell lines, whereas expression of TIMP-1 was much higher in IN500 than in other cell lines. Zymographic activity was found to be comparable to MMP-2 mRNA levels in all cell lines except for CCF-STTG1. Type IV collagenolytic activity was also comparable to invasion activity in nine cell lines. These observations suggest the role of type IV collagenase and its inhibitors in determining capacity for invasion by human gliomas. However, a comprehensive analysis both in vitro and in vivo is required to confirm the role for this enzyme in glioma cell invasiveness.
Clin Exp Metastasis 1994 Jul
PMID:Expression of 72 kDa type IV collagenase and invasion activity of human glioma cells. 803 4

The expression of metalloproteinases, such as type IV collagenase/gelatinase, enables tumor cells to degrade type IV collagen present in the basement membrane and correlates with metastatic potential of several tumor types. We found that increased levels of rat serum type IV collagenolytic activity are associated with increased 13762NF mammary adenocarcinoma metastases in lungs and lymph nodes of syngeneic rats. To investigate serum metalloproteinases responsible for type IV collagenolysis, we performed zymography and Western blot analysis of rat sera. A M(r) 92,000 progelatinase (progelatinase B, M(r) 92,000 type IV procollagenase, MMP-9) was detected on zymograms of rat sera within 16 days after intramammary fat pad inoculation of highly metastatic MTLn3 cells. The activated serum M(r) 92,000 progelatinase degraded sodium dodecyl sulfate-denatured type I and IV collagens but was not active on casein, albumin, hemoglobin, and immunoglobulin. Sera from rats with fat pad tumors and lung metastases formed from highly metastatic clones possessed greater than 7 times higher levels of serum M(r) 92,000 progelatinase than control sera or sera from rats bearing similar size fat-pad tumors of low or nonmetastatic clones. The results were confirmed by Western blot analysis of rat sera using rabbit anti-human M(r) 92,000 progelatinase antibodies. Similar results were obtained from the analysis of rat plasma samples. The serum and plasma M(r) 92,000 progelatinase levels correlated with the extent of metastases in the lung and lymph nodes. The results indicate that high levels of serum and plasma M(r) 92,000 progelatinase are associated with the presence of disseminated metastatic adenocarcinoma cells and suggest that this enzyme may facilitate the invasion of blood-borne tumor cells through vascular basement membranes.
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PMID:Serum and plasma M(r) 92,000 progelatinase levels correlate with spontaneous metastasis of rat 13762NF mammary adenocarcinoma. 824 39

Tumor invasion and metastasis formation are major obstacles for successful cancer therapy. Metastasis is a complex multistep process that requires sequential interactions between the invasive cell and the extracellular matrix. A model system for tumor invasion of extracellular matrix barriers has been developed, and application of this model has facilitated our understanding of the molecular mechanisms of metastasis formation. This model consists of three steps: tumor cell adhesion, extracellular matrix proteolysis, and cell migration. The role of the matrix metalloprotease enzymes in tumor cell-mediated extracellular matrix proteolysis is well established. We review the functional domain structure of the matrix metalloprotease enzymes in general and specifically the interaction of metastasis-associated gelatinase A (72-kDa type IV collagenase) with the tissue inhibitor of metalloproteases-2 (TIMP-2). We also discuss the physiologic activation of the matrix metalloprotease enzymes and the specific cellular mechanism of action of gelatinase A.
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PMID:Extracellular matrix 6: role of matrix metalloproteinases in tumor invasion and metastasis. 826 28

A new cultured cell line (KG-2) derived from human renal cell carcinoma and a metastatic model in nude mice were studied. KG-2 was cultured from renal cell carcinoma (clear cell carcinoma) of the left kidney. In vitro doubling time of KG-2 was approximately 50 hours. KG-2 cells produced tumors in both the subcutaneous and renal sub-capsular space in nude mice, with tumorigenicity of 75%, showing no difference between the two sites. Histologically, tumors formed in the subcutaneous sites were hypovascular granular cell carcinoma. Moreover, each tumor was encapsulated by a thick fibrous capsule and never produced distant metastasis or invasion into the surrounding tissue. However, tumors formed in the subrenal capsular space were clear cell carcinoma. These tumors were hypervascular, and produced distant metastases. The most common metastatic site was the lung. Immunohistochemical analysis using anti-human collagenase type IV antibody on tumors formed in subcutaneous and subrenal capsular sites demonstrated that the expression of this enzyme in tumors formed in the subrenal capsular space was much higher than that in tumors formed in the subcutaneous site. Additionally, immunohistochemical study using anti-mouse collagen type IV antibody, a major components of the vascular wall, demonstrated many small densely growing vessels in tumors formed in the subrenal capsular space. In contrast, few vessels were produced in tumors formed in subcutaneous sites. These findings suggest that factors relating to the different injection sites may regulate the production of collagenase type IV secreted by KG-2 cells and neovascularity in nude mice. This metastatic model may be useful in the study of the mechanism of cancer metastases.
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PMID:[Establishment and characterization of a new human renal cell carcinoma cell line (KG-2) and metastatic model in nude mice]. 834 19

Matrix metalloproteinases (MMPs) are a group of enzymes thought to be responsible for both normal connective-tissue-matrix remodelling and the accelerated breakdown associated with tumor development. These MMPs and tissue inhibitor of MMPs (TIMP1) could be expressed by either the cancer or the stromal cells. Expression of mRNAs encoding interstitial collagenase (MMP1), 72-kD type IV collagenase (MMP2) and stromelysin (MMP3), which are probably involved in tumor invasion and metastasis, and of TIMP1 were studied in human mammary pathology by in situ hybridization and Northern blot analysis. Out of 6 benign lesions, 2 expressed MMP2 mRNAs. mRNAs encoding MMP1 and MMP3 were detectable in occasional stromal and tumor cells in 2 out of 17 carcinomas. Thirteen out of 17 cancers expressed MMP2 mRNA throughout the tumor in stromal cells close to noninvasive tumor clusters and well-differentiated invasive cancer cells. TIMP1 mRNA expression was detected in noninvasive and well-differentiated invasive tumor cells. These data suggest that there is a cooperation between tumor and stromal cells, in particular for the production of 72-kD type IV collagenase, involved in the disruption of basement membranes. A lack of TIMP1 expression from invasive cancer cells would also contribute to matrix destruction.
Invasion Metastasis 1993
PMID:Detection and localization of mRNAs encoding matrix metalloproteinases and their tissue inhibitor in human breast pathology. 840 9

Overproduction of matrix metalloproteinases (MMPs) is a common characteristic of metastatic cancer cells. Since MMPs can be identified in plasma, we proposed that enhanced MMP-9 secretion by invasive cancer cells may be detected by plasma assay. To this end, we developed a specific sandwich enzyme-linked immunosorbent assay which uses two mouse monoclonal antibodies to human M(r) 92,000 type IV collagenase (MMP-9). The plasma concentration of MMP-9 (mean +/- SD) in 60 healthy subjects (9 +/- 11 ng/ml), 136 patients without cancer, and 179 patients with cancer of the lung, genitourinary tract, or lymphomas-leukemias did not differ significantly. In contrast, plasma MMP-9 was significantly increased (P < 0.01) in 122 patients with gastrointestinal tract cancer and breast cancer (18 +/- 23 and 21 +/- 22 ng/ml, respectively). Whereas carcinoembryonic antigen levels were significantly increased in patients with stage IV gastrointestinal cancer, MMP-9 concentrations were not significantly increased in patients with metastatic disease as compared to those with nonmetastatic cancer. Combining both assays improves sensitivity of detection of colon cancer. MMP-9 was also significantly increased during pregnancy which is consistent with the extensive ongoing tissue remodeling and the leaching of the tissue proteinase into plasma.
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PMID:M(r) 92,000 type IV collagenase is increased in plasma of patients with colon cancer and breast cancer. 841 38

To investigate the effect of matrix-degrading enzymes on the malignant potential of oral squamous cell carcinoma, the expression of matrix metalloproteinase-2 (MMP-2/72-kD gelatinase/type IV collagenase) in 46 patients who had neck surgery for oral cancer was studied immunohistochemically. In 20 of 26 patients (76.9%) with lymph node metastases, proMMP-2 was strongly expressed, whereas the production of proMMP-2 in tissue was detected only in 5 of 20 patients (25%) who had no lymph node metastases. In tissue specimens, proMMP-2 was expressed in a diffuse invasive mode and in the advancing front of cancer. Because MMP-2 can degrade type IV collagen composed of basement membrane, these results suggest that the in vivo production of the enzyme by cancer is an indicator of the degree of malignancy, and that the analysis of proMMP-2 expression is useful to evaluate the malignant potential in individual oral squamous cell carcinoma.
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PMID:Expression of matrix metalloproteinase-2 related to lymph node metastasis of oral squamous cell carcinoma. A clinicopathologic study. 842 10


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