Ethaselen (BBSKE) is an orally active, selective thioredoxin reductase (TrxR) inhibitor with IC 50 s of 0.5 and 0.35 μM for the wild-type human TrxR1 and rat TrxR1, respectively. Ethaselen specifically binds to the unique selenocysteine-cysteine redox pair in the C-terminal active site of mammalian TrxR1. Ethaselen, an organoselenium compound, is a potent antitumor candidate that exerts potent inhibition on non-small cell lung cancer (NSCLC) by targeting TrxR.

Ethaselen (2.5-10 μM; 12, 24 hours) suppresses A549 cell viability in a both concentration- and time-dependent manner. H1666, which has considerably lower TrxR1 expression level, is less susceptible to 24 h treatment with Ethaselen[1]. Ethaselen inhibits the intracellular TrxR1 activity in a concentration- and time-dependent manner, with IC 50 values of 4.2 and 2 μM for 12- and 24-h treatments, respectively[1]. Ethaselen (2.5-10 μM; 12, 24 hours) has no effect on the protein amounts of TrxR1 and Trx. The mRNA level of TrxR1 does not show significant alteration in Ethaselen-treated A549 cells[1]. Ethaselen (2.5-50 μM; 1-24 hours) causes intracellular Trx oxidation in A549 cells[1]. Ethaselen (5-10 μM; 12, 24 hours) causes a clear concentration-dependent increase in ROS levels in A549 cells[1]. The inhibition constants for Ethaselen binding to free enzyme (K i ) and the enzyme-substrate complex (K is ) were determined to be 0.022 and 0.087 μM, respectively. Ethaselen also inhibits mammalian TrxR1 in a time-dependent manner possibly by forming a covalent Se-S bond with Cys497 of Trx[1]. Cell Viability Assay[1]Cell Line: A549 cell Concentration: 2.5, 5, 7.5, 10 μM Incubation Time: 12, 24 hours Result: Suppressed A549 cell viability in a both concentration- and time-dependent manner.

Ethaselen (BBSKE; 36-108 mg/kg/day; PO; for 10 days) shows increased inhibition of tumor growth in a dose-independent manner[2]. Animal Model: Five-week-old female BALB/c nude mice with A549 cell[2]Dosage: 36, 72, 108 mg/kg Administration: PO; daily; for 10 days Result: Showed increased inhibition of tumor growth, and the inhibition levels increased with the dose. The TrxR activity levels of the high dose group (108 mg/kg) decreased more than the middle dose group (72 mg/kg) and low dose group (36 mg/kg).

217798-39-5

C16H12N2O2Se2

422.226

BBSKE;Ethaselen

(< 1 mg/ml refers to the product slightly soluble or insoluble )
Powder: -20°C for 3 years
In solvent: -80°C for 2 years