Echinoside A from Pearsonothuria graeffei Exert the Cytotoxicity to MDA-MB-231 Cells via Mitochondrial Membrane and Modulation of PI3K/Akt/mTOR Pathway

A kind of triterpene glycosides echinoside A(EA)was extracted from sea cucumber Pearsonothuria graeffei,and its yield was about 0.78%.The purity of EA was 99.0%,and its molecular weight was 1206 Da.EA was a linear tetrasaccharide attached to a pentacyclic triterpene aglycon.It inhibited the growth of MDA-MB-231 cells in vitro.The antitumor effect was related to elevate ROS level,decrease mitochondrial membrane potential,enhance caspase-3 expression,induce cells apoptosis and arrest cell cycle at G2/M phase.EA also dose-dependently suppressed the expressions of phophorylation proteins p-PI3K,p-Akt,and p-mTOR as analyzed by western blotting.These results suggested that EA caused MDA-MB-231 cells apoptosis via intrinsic mitochondrial and PI3K/Akt/mTOR pathway.EA can be a potential anti-breast cancer agent to enhance the clinical efficacy.