Abstract
To elucidate the invasion mechanism of oral squamous cell carcinoma, we recently devised a new in vitro invasion model. In the present study, three kinds of oral squamous cell carcinoma cell lines (OSC-19, 0SC-20, KB) were cultured on collagen gels, and basement membrane components and matrix metalloproteinases (MMPs) produced by carcinoma cells in this model were investigated.
Production of basement membrane components (laminin, type IV collagen, fibronectin) varied among the three carcinoma cell lines. Invasive OSC-19 cells were characterized by higher secretion of fibronectin than OSC-20 or KB cells. As to matrix metalloproteinases (MMPs), zymography using gelatin substrate gel showed serveral bands of 72kDa, 92kDa, 95kDa and 50-55kDa. By western blotting, 72kDa gelatinase (MMP-2), 92kDa gelatinase (MMP-9), collagenase (MMP-1) were detected. These enzymes were enhanced by supPlement of 3T3 cells into collagen gels. Gelatinolytic activity and collagenolytic activity were assayed, and the former was detected in OSC-19 and OSC-20 cells and the latter in OSC-20 cells.
These results suggest that the invasive activity of oral squamous cell carcinoma is correlated with cell-matrix adhesion by fibronectin and with degradation of the matrix by metalloproteinase, especially, MMP-9 and MMP-1.
