Abstract
Breast cancer is the most common cancer type among female worldwide. Cisplatin (cDDP) is one of the most effective chemotherapies for the treatment of breast cancer. Nevertheless, there is an urgent requirement to reduce its systemic side effects and chemoresistance. In this present study, pivalopril (PP), a clinically used antihypertensive drug, has been verified as a chemosensitizer that extremely improves the sensitivity of breast cancer cells to cDDP. PP treatment markedly promoted the capacity of cDDP to reduce the proliferation of breast cancer cells. The combination of PP and cDDP significantly induced apoptosis and inhibited vascular endothelial growth factor (VEGF) expression in breast cancer cells, accompanied with reduced angiogenesis. Furthermore, PP plus cDDP effectively reduced the cell migration and invasion in breast cancer cells. The in vivo studies confirmed that the anti-metastatic effect of cDDP was further improved by PP, as evidenced by the markedly decreased number of metastatic nodules in lungs. Moreover, we confirmed that PP combined with cDDP cooperatively suppressed tumor growth in breast cancer xenograft mouse models without extra toxicity. Together, the present study provided the first evidence that PP greatly sensitized breast cancer cells to cDDP without additional toxicity, and the synergistic effect may be mainly through cooperatively inhibiting proliferation, angiogenesis, metastasis, and inducing apoptotic cell death.