Saikosaponin D potentiates the antineoplastic effects of doxorubicin in drug-resistant breast cancer through perturbing NQO1-mediated intracellular redox balance

Drug resistance to doxorubicin (DOX) significantly limits its therapeutic efficacy in breast cancer (BC) patients. Saikosaponin D (SSD), a triterpene saponin derived from the traditional herb Radix Bupleuri, has shown promise as a chemotherapeutic sensitizer in preclinical studies due to its notable antitumor activity. However, the role and mechanism of SSD in DOX-resistant BC cells remain largely unexplored.