Mechanism of Tetrandrine in Combination with Droloxifen To Reverse Multidrug Resistance in Leukemia.

Objective: The study aims to investigate the effect of Tetrandrine (Tetrandrine, Tet) in combination with Droloxifen (Droloxifen, DRL) on the expression of NF-κB(nuclear factor kappaB) of K562 and K562/A02 cell lines and the reversal mechanism of this combination. Method: The activation of NF-κB in K562 and K562/A02 cell lines and the effect of Tet,DRL alone or in combination on NF-κB were determined with Immunocytochemistry and Western blotting respectively. Results: K562/A02 cells displayed higher level of NF-κB protein expression than their parental K562 cells; The application of Tet or DRL alone or in combination had no effect on NF-κB expression in K562 cells at 6h and 12h; Tet and DRL used alone or in combination could significantly down-regulate NF-κB protein expression in nucleaus of K562/A02 cells. The effect was more significant in combination of Tet and DRL than the application of single drug. This decrease became more significant at 12h than at 6h. Conclusions: Activation of NF-κB may be involved in the mechanism of MDR of K562/A02 cell line; Inhibition of NF-κB activation may be involved in the mechanism of multidrug resistance reversal to K562/A02 line of Tet and DRL.