Solamargine inhibits migration and invasion of human hepatocellular carcinoma cells through down-regulation of matrix metalloproteinases 2 and 9 expression and activity

Solamargine is a steroidal alkaloid glycoside isolated from Solanum nigrum. The aim of this study was to investigate the effects of solamargine on tumor migration and invasion in aggressive human hepatocellular carcinoma cells. The MTT assay was used to assess the effects of solamargine on the viability of HepG2 cells. Migration and invasion ability of HepG2 cells under solamargine treatment were examined by a wound healing migration assay and Boyden chamber assay, respectively. Western blotting assays were used to detect the expression of MMP-2 and MMP-9 proteins and MMP-2 and MMP-9 activity were analyzed by gelatin zymography assay. Solamargine reduced HepG2 cell viability in a concentration-dependent manner. At 7.5μM solamargine decreased cell viability by less than 20% in HepG2 cells. A wound healing migration assay and Boyden chamber invasion assay showed that solamargine significantly inhibited in vitro migration and invasion of HepG2 cells. At the highest dose, solamargine decreased cell migration and invasion by more than 70% and 72% in HepG2 cells, respectively. Western blotting and gelatin zymography results showed that solamargine reduced expression and function of MMP-2 and MMP-9 proteins. In conclusion, the results showed that solamargine significantly inhibits migration and invasion of HepG2 cells by down-regulating MMP-2 and MMP-9 expression and activity.