[The relation between integrin, type IV collagenase and extracellular matrix in invasion and metastasis of gastric carcinoma].

The expression of integrin Alpha-6-subunit, laminin, type IV collagenase, type IV collagen and ras p21 were studied immunohistochemically in gastric cancer. The results showed that the expression of alpha 6 and laminin (LN) was often in continuous or interrupted linear pattern in the expanding type of gastric carcinoma (GC); while in the infiltrating type of GC, they were expressed either in interrupted spotty or fragmentary pattern, or almost lost. Suggesting that the interaction between the laminin receptor and its ligand may influence the mode of growth in GC. Intense expression of type IV collagenase was often found in GC cells, especially in the infiltrative type of GC and in those with lymph node metastasis, it can therefore be used as a marker for invasion and metastasis of GC cells. A positive correlation was found between the expression of type IV collagenase and ras p21 in GC. The expression of type IV collagen was similar to that of laminin, but in reverse proportion to the expression of type IV collagenase. These investigations provide a better understanding of the molecular pathological basis of tumor invasion and metastasis.