Baicalin Induces Apoptotic Death of Human Chondrosarcoma Cells through Mitochondrial Dysfunction and Downregulation of the PI3K/Akt/mTOR Pathway

Abstract

AbstractThe aim of the present study was to investigate the cytotoxic and antitumour effects of baicalin in human chondrosarcoma both in vivo and in vitro. We examined the effects of baicalin on the growth and apoptosis of human chondrosarcoma cells. Baicalin inhibited the growth of SW1353 and CH2879 cells in a dose- and time-dependent manner, but did not inhibit the growth of normal chondrocytes. Baicalin reduced tumour growth and induced apoptotic death in SW1353-transplanted nude mice without reducing their body weight. Further studies showed that baicalin reduced the mitochondrial membrane potential, upregulated the expression of Bax and cytoplasmic cytochrome c, downregulated the expression of Bcl-2 and mitochondrial cytochromes, and activated caspase-3 and caspase-9. Baicalin inhibited the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathway by decreasing the expression of phosphorylated phosphoinositide 3-kinase, phosphorylated protein kinase B, and phosphorylated mammalian target of rapamycin both in vivo and in vitro. Moreover, the mice that received SC79 and baicalin exhibited a greater tumour size compared with the mice that received baicalin. The mice that received LY294002 and baicalin showed a smaller tumour size compared with the mice that received baicalin. In the in vitro study, SC79 and LY294002 affected the baicalin-induced cytotoxic effects on chondrosarcoma cells in the same manner. Our data suggest baicalin has therapeutic efficacy in human chondrosarcoma through the induction of apoptosis and inhibition of the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathway. Baicalin can be considered a potential therapeutic agent for treating chondrosarcomas.