[Expression of membrane-type matrix metalloproteinase (MT-MMP) and activation of MMP-2 in lung cancer].

: In this study, we investigated the correlation between the expression of MMP-2 and lymph node metastasis by analyzing 58 cases of primary lung cancer. Furthermore we studied expression of membrane-type MMP (MT-MMP) which was identified as an activator of MMP-2 and its relation to the activation ratio of MMP-2 in tumor tissues. Activated form of MMP-2 was detected specifically in the tumor tissues by zymography, and the activation ratio was significantly higher in 20 cases of the lymph node metastasis positive group than in other 38 cases. Additionally, northern blott analysis showed that MT-MMP was overexpressed in cancer tissues and that the expression of MT-MMP was closely related to the amount of activated form of MMP-2. These results indicated that MMP-2, which is activated by MT-MMP expressed on the surface of tumor cells, play a role in tumor metastasis by degrading surrounding basement membranes.