Emerging evidence has shown that
daphnoretin, one of the main active ingredients of Daphne giraldii Nitsche, processes antitumor activities in several
tumor cells (e.g.,
colon cancer,
lung cancer,
cervical cancer, and
osteosarcoma). However, the antitumor effect and its mechanism in
breast cancer are unexplored. In this study, our data indicated that
daphnoretin obviously suppressed the proliferation of
breast cancer MCF-7 and MDA-MB-231 cells. Further studies showed that
daphnoretin remarkably increased the p21 level, decreased
cyclin E and CDK2 levels, and then arrested the cell cycle at the S phase. Moreover,
daphnoretin obviously lowered the BCL-2 level and raised the levels of BAX and cleaved
caspase-9 and -3, leading to cell apoptosis. Furthermore,
daphnoretin remarkably decreased the ratio of p-PI3K/PI3K and p-AKT/AKT in
breast cancer cells. Collectively, these findings demonstrated that
daphnoretin could suppress
breast cancer cell proliferation through cell cycle arrest and inducing apoptosis, which is related to the PI3K/AKT pathway.