[Role of type IV collagenase in tumor cell invasion and effect of laminin on invasive potential in bile duct carcinoma].

In the present experiment, the secretion of type IV collagenase, the invasive potential of tumor cell in vitro, and the effects of exogenous laminiu and anti-laminin antibody on the invasive potential of tumor cells in a newly established cell line of bile duct carcinoma, QBC939, were observed by using an amnion invasion culture system and a substrate capture immunoassay. The biological mechanism of tumor invasion, especially the role of the type IV collagenase in the invasive process, was discussed. QBC939 cells secreted type IV collagenase with high invasive potential. Different doses of laminin (1 micrograms, 5 microgram, 10 microgram/ml) stimulated the release of type IV collagenase and increased the invasive potential of the tumor cells in varying degrees. The effect of laminin could be antagonized by the anti-laminin antibody. The results demonstrate that the type IV collagenase is one of the important enzymes involved in the tumor invasion. The effects of laminin on the release of type IV collagenase and the invasive potential suggest that laminin play an important role in mediation of tumor invasion. The results also suggest that inhibiting type IV collagenase or blocking the effect of laminin on tumor cells may be a prospective therapy for tumor treatment in future.