Terminalia catappa L. was a popular folk medicine and has several proven biological activities including antioxidant and anti-inflammatory. The present study investigated the effect of the extract of T. catappa leaves (TCE) on invasion and motility of tumor cells to find that TCE exerted a dose-dependent inhibitory effect on the invasion and motility of highly metastatic A549 and Lewis lung carcinoma (LLC) cells. To further investigate the precise involvement of TCE in tumor metastasis, A549 and LLC cells were treated with TCE at various concentrations, up to 100 microg/mL, for a specified period and results from zymography and Western blotting showed that a TCE treatment may decrease the expressions of matrix metalloproteinase-2, -9, urokinase plasminogen activator and their endogenous inhibitors, that is tissue inhibitor of metalloproteinase-2 and plasminogen activator inhibitor-1, in a concentration-dependent manner. Furthermore, the inhibitory effect of TCE on the growth and metastasis of LLC cells in vivo was proven. These results indicated that TCE could be applied to be a potential antimetastatic agent.
