Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.3 (collagenase)
 18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We used affinity chromatography to isolate a specific laminin-binding protein from murine fibrosarcoma cells. These cells bind exogenous laminin to their surface with high affinity (Kd = 2 X 10(-9)M for laminin) with approximately 5 X 10(4) sites per cell. Laminin affinity chromatography of [35S]methionine-labeled cell extracts produced two distinct proteins. One was identified as Type IV (basement membrane) collagen based on its migration pattern on SDS gels and bacterial collagenase sensitivity. The other protein, which migrates as a single band or closely spaced doublet on reduced SDS gels, has a reduced molecular weight of 69,000. Using a nitrocellulose filter disk assay, we found that the latter protein specifically bound 125I-laminin with the same high affinity (Kd = 2 X 10(-9)M for laminin) as did intact fibrosarcoma cells. By iodinating intact cells, we demonstrated that this laminin-binding protein is on the cell surface. We conclude that this protein with reduced molecular weight of 69,000 is a subunit or component of a larger cell surface receptor protein for laminin in this fibrosarcoma model. This laminin receptor may mediate the interaction of the cell with its extracellular matrix.
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PMID:Isolation of a cell surface receptor protein for laminin from murine fibrosarcoma cells. 630 2

Ascitic ovarian cancer cells, which derive from solid tumors, complicate the treatment of ovarian cancer by spreading throughout the peritoneal cavity. Because basement-membrane components may influence tumor-cell proliferation and dissemination, the present studies examined the production of (a) basement-membrane attachment and migration factors (laminin, fibronectin and type IV collagen); (b) a laminin receptor, the 32/67-kDa laminin-binding protein, the presence of which correlates with malignancy; and (c) metalloproteinases (types I and IV collagenase and stromelysin), by ascitic and cultured OVCAR-3 cells and solid OVCAR-3 tumors. The cultured cells and solid tumors produced high levels of mRNA encoding attachment factors and metalloproteinases, and low levels of mRNA for the 32/67-kDa laminin receptor. In contrast, the ascitic ovarian cells had low or undetectable levels of mRNA encoding laminin, type IV collagen and metalloproteinases, but higher levels of transcripts for the laminin receptor. Our results suggest that the apparent inability of ascitic OVCAR-3 cells to attach to host-tissue surfaces may be a consequence, in part, of low levels of expression of laminin, type IV collagen and/or type IV collagenase.
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PMID:Altered expression of basement-membrane components and collagenases in ascitic xenografts of OVCAR-3 ovarian cancer cells. 834 42