Abstract
Doxorubicin (DOX) is currently the preferred chemotherapeutic agent for breast cancer, and hydroxyl safflower yellow B (HSYB) has a tumor growth-inhibiting activity. The present study aimed to investigate the effects of HSYB combined with DOX on the proliferation of human breast cancer MCF-7 cells and explore the underlying mechanism. MTT and cell colony formation assays revealed that the proliferation rate of MCF-7 cells was signifiscantly decreased after HSYB and DOX treatment. Combined HSYB and DOX treatment significantly decreased the expression levels of BCL-2 in MCF-7 cells, while the expression levels of apoptosis-associated proteins, including cleaved caspase-9, BAX and cleaved caspase-3, were markedly increased. Furthermore, flow cytometry and western blot analysis demonstrated that combined HSYB and DOX treatment stimulated an increase in intracellular reactive oxygen species and promoted the release of cytochrome c, leading to apoptosis. The current data suggested that the combination of HSYB and DOX may have marked antitumor activity.