Our previous study showed that human peritoneal conditioned median (CM) increased the matrix metalloproteinase-9 (MMP-9) secretion and invasiveness of ovarian cancer cells (NOM1). In an effort to identify this MMP-9- stimulating factor, we examined the effects of extracellular matrix components, such as type IV collagen, laminin, and fibronectin, on ovarian cancer cells. We found that fibronectin increased the MMP-9 activity of NOM1 cell CM in a concentration-dependent manner and that peritoneal CM contained high level of fibronectin. An increase of MMP-9 activity in NOM1 cell CM by the peritoneal CM was almost completely blocked by 20 μg/ml of anti-integrin α5/FnR antibody and RGD polypeptides. Furthermore, after immunoprecipitation by antifibronectin antibody supernatant of the peritoneal CM did not increase MMP-9 activity in NOM1 cells. Fibronectin and the peritoneal CM also increased MMP-9 activity and expression in NOM1 cell lysate, and these effects were blocked by anti-integrin α5/FnR antibody. Invasiveness of NOM1 cells was enhanced by fibronectin and the peritoneal CM in a concentration- dependent manner, and anti-integrin α5/FnR antibody blocked these effects. These results suggested that fibronectin secreted from peritoneum increased MMP-9 activity and expression, and, in turn, invasiveness of ovarian cancer cells.
|Number of pages||5|
|Publication status||Published - 01-12-1997|
All Science Journal Classification (ASJC) codes
- Cancer Research