Irosustat

Irosustat is a potent steroid sulfatase inhibitor, with an IC₅₀ of 8 nM, and exhibits anti-breast cancer activity. IC50 & Target: IC50: 8 nM (Steroid sulfatase)^[1], 0.2 nM (Steroid sulfatase, MCF-7 cells)^[2] In Vitro: Irosustat (667 COUMATE) is a potent steroid sulfatase inhibitor, with an IC₅₀ of 8 nM^[1]. Irosustat (667 COUMATE) inhibits steroid sulphatase (STS) activity in MCF-7 cells with an IC₅₀ of 0.2 nM, but has no effect on the morphology or proliferation of MCF-7 cells at 10 μM^[2]. In Vivo: Irosustat potently inhibits rat liver, with inhibition of >90% when at a 1 mg/kg concentration. Irosustat (2 mg/kg, p.o. for 5 d) blocks the uterine growth stimulated by oestrone sulfate (E1S) in ovariectomized rats. In addition, Irosustat (2, 10 mg/kg, p.o.) plus E1S dose-dependently decreases the growth of NMU-induced mammary tumors in ovariectomized rats^[1]. Irosustat (667 COUMATE; 10 mg/kg, p.o.) shows 97.9 ± 0.06% inhibition on steroid sulphatase (STS) activity in rat liver^[2].