Puerariae radix (PR) is a popular natural herb and a traditional food in Asia, which has antithrombotic and
anti-allergic properties and stimulates estrogenic activity. In the present study, we investigated the
effects of the PR isoflavones puerarin, daidzein, and genistein on the growth of breast cancer cells. Our
data revealed that after treatment with PR isoflavones, a dose-dependent inhibition of cell growth
occurred in HS578T, MDA-MB-231, and MCF-7 cell lines. Results from cell cycle distribution and apoptosis
assays revealed that PR isoflavones induced cell apoptosis through a caspase-3-dependent pathway
and mediated cell cycle arrest in the G2/M phase. Furthermore, we observed that the serum metabolites
of PR (daidzein sulfates/glucuronides) inhibited proliferation of the breast cancer cells at a 50% cell
growth inhibition (GI50) concentration of 2.35 lM. These results indicate that the daidzein constituent
of PR can be metabolized to daidzein sulfates or daidzein glucuronides that exhibit anticancer activities.
The protein expression levels of the active forms of caspase-9 and Bax in breast cancer cells were significantly
increased by treatment with PR metabolites. These metabolites also increased the protein expression
levels of p53 and p21. We therefore suggest that PR may act as a chemopreventive and/or
chemotherapeutic agent against breast cancer by reducing cell viability and inducing apoptosis.
關聯:
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 378(4):683~688
