Abstract
Activation of the phosphoinositide 3 kinase (PI3K)/AKT pathway is frequently implicated in resistance to anticancer therapies. PI3K inhibitors can restore sensitivity to standard breast cancer therapies, including endocrine therapy, HER2-targeted agents, and chemotherapy. Our previous research showed that econazole, a novel PI3Ka inhibitor, inhibits the PI3K/AKT pathway and induces apoptosis in lung cancer cells. In this study, econazole showed significant cytotoxic activity against Adriamycin-resistant breast cancer cells in vitro and in vivo. Additionally, econazole significantly sensitized MDA-MB-231 and MCF-7 cells to Adriamycin via inhibiting the PI3K/AKT pathway. Overexpression of constitutively active AKT1 abolished the function of econazole. The combination of econazole and Adriamycin exerted synergistic inhibitory effects in breast cancer cells in vitro and in vivo. Taken together, the PI3K inhibitor econazole could effectively overcome Adriamycin resistance and showed synergistic effects with chemotherapy on breast cancer.