Study On The Mechanism Of Emodin Methyl Ether 8-O-?-glucopyranoside In Inhibiting Melanoma Metastasis

OBJECTIVE:To study the effect of emodin methyl ether 8-o-pit-pyranosinosine which is the main component of Chinese herbal medicine lamb's foot on skin melanoma metastasis and its mechanism.METHODS:Human skin melanoma A375 cells were treated with different concentrations of physiocn 8-O-?-glucopyranoside,and the cell activity of A375 cells was detected by the CCK-8.The migration of A375 cells was measured by wound healing test and the invasion was examed by transwell test.RT-PCR and Western-blot were performed to detect the transcription and expression of COX-2.ELISA detection was used to measure the activity of c-jun and the phosphorylation of c-jun was certified by western-blot.COX-2 was silenced with si RNA and overexpressed with its plasmid.C-jun was silenced by inhibitor SP60012 and overexpressed with its plasmid.The si RNA,inhibitor and plasmids were used in the detection of migration and invasion in melanoma cells.RESULTS:Physiocn 8-O-?-glucopyranoside effectively reduces the activity of A375 cells and inhibits the migration and invasion of A375 cells;Physiocn 8-O-?-glucopyranoside can by inhibiting the m RNA transcription level and the expression of COX-2,the migration and invasion of A375 cells can be inhibited;overexpression of COX-2 can significantly promote the invasion and migration of A375 cells;and silencing COX-2 can significantly inhibit the migration and invasion of A375 cells.COX-2 upstream factor AP-1 is composed of c-jun and c-fos.The activity and the phosphorylation of c-jun were greatly inhibited by physiocn 8-O-?-glucopyranoside treatment in A375 cells.Meanwhile no changes were observed on c-fos in the same situation.The expression and transcription of COX-2 were deceased in the SP60012 treated group and increased in the COX-2 overexpression group.CONCLUSION: Physiocn 8-O-?-glucopyranoside inhibits the invasion and migration of A375 cells by reducing c-jun phosphorylation,down-regulating COX-2 expression and inhibiting AP-1 activity.