Molecular docking studies of a quassinoid and P-glycoprotein

P-glycoprotein (P-gp) over expression is often linked to the multidrug resistance (MDR) in mammalian cell lines and human cancers. Quassinoid is a type of compound extracted from Eurycoma longifolia Jack (Tongkat Ali) that have been shown to display anti-cancer, anti-malarial and anti-viral effects on various cell types. In this study, molecular docking method was used to explore potential binding interactions between a quassinoid and the human P-gp. SITEHOUND-webserver was used to predict the potential binding pockets of P-gp. Two programs, Docking@UTMB web server and AutoDock Vina software were utilized to dock the quassinoid to P-gp. Both programs showed that quassinoid forms hydrogen bonds with GLN 946 and TYR 953 residues. In fact, these residues were shown to interact with known drug compounds.