Changes in FAK activation in these cells MG132 proteasome were further evaluated using antibodies directed against the FAK phosphorylation site Tyr925. Western blotting showed that TPA significantly increased the Src and FAK phosphorylation of HONE 1 cells in a time dependent manner. Moreover, STE reduced the phosphorylation of Src and FAK in HONE 1 cells, suggesting that STE inhibited HONE 1 cell migration, at least in part, through the regu lation of Src and FAK phosphorylation. Effects of STE on MAPK pathways After the inhibitory effects of STE on cell migration invasion and proteinases were revealed, the effects of STE on the expressions of MAPK pathways were in vestigated using Western blotting to elucidate their underlying mechanisms.

Western blotting showed that TPA significantly increased the three MAPK pathway phosphorylations of HONE 1 cells in a time dependent manner. Furthermore, STE reduced the phosphorylation of ErK1 2 in HONE 1 cells, but not the phosphorylation of the JNK and p38 pathways. To further determine whether STE inhibition of MMP 9 activity was caused mainly by the inhibition of the Erk 1 2 signaling pathway, its effects on a specific inhibitor of the Erk1 2 pathway in HONE 1 cells were inves tigated. In the gelatin zymography assay, TPA induced MMP 9 activity of HONE 1 cells was significantly reduced by the Erk 1 2 inhibitor. The results also showed that a combined treatment of the Erk 1 2 in hibitor and STE further reduced MMP 9 expression. Thus, the inhibition of the Erk 1 2 signaling pathways might result in reduced MMP 9 expression.

Discussion The nasopharynx is situated over the base of the skull where lymphatic tissues and circulation are rich. Metastases of nasopharyngeal cancer cells to the neck lymph nodes and distant organs are common in NPC patients, even in the early stage of the disease. Herbal medicines are a popu lar practice of healthcare in eastern countries. Numerous studies have shown that they are beneficial in the treatment of many diseases, including cancers. Although the anti tumor activities of several herbal medicines against hu man NPC cells have been demonstrated previously, there is no data in current literature regarding the anti metastatic activity of herbal medicine for NPC cells. The present study demonstrates that the extract of Selaginella tamariscina can significantly inhibit the migration and in vasion ability of HONE 1 cancer cells, suggesting a poten tial role in the treatment of metastatic NPC.

A degradation of the ECM and components of the basement membrane by MMPs play a crucial role in the development of cancer metastasis. AV-951 In vivo evidence from chicken chorio allantoic membrane assay shows that MMP 9 is inter dependent in tumor invasion, while tumor cells show only low levels of invasion in the absence of MMP 9. Itoh et al.