escin Ia

Escin IA is a triterpene saponin isolated from horse chestnut, which inhibits HIV-1 protease with IC50 values of 35 μM. Escin IA has anti-TNBC metastasis activity, and its action mechanisms involved inhibition of epithelial-mesenchymal transition process by down-regulating LOXL2 expression.

The saponin fraction of Aesculus chinensis Bunge fruits (SFAC) could inhibit the invasion and migration of MDA-MB-231 cells. Among which, Escin IA showed more potent inhibition of the invasion than other five main saponin constituents. It selectively reduced the expression of LOXL2 mRNA and promoted the expression of E-cadherin mRNA, and prevented the EMT process of MDA-MB-231 cells and TNF-α/TGF-β-stimulated MCF-7 cells. Moreover, it reduced the LOXL2 level in MDA-MB-231 cells but not in MCF-7 cells. When MCF-7 cells were stimulated with TNF-α/TGF-β, transfected with LOXL2 or treated with hypoxia, Escin IA down-regulated the level of LOXL2 in MCF-7 cells. Meanwhile, Escin IA suppressed the EMT process in LOXL2-transfected or hypoxia-treated MCF-7 cells. Of interest, Escin IA did not alter the level of HIF-1α in hypoxia-induced MCF-7 cells.In TNBC xenograft mice, the metastasis and EMT of MDA-MB-231 cells were suppressed by Escin IA.