Antioxidant and Cell Growth Inhibitory Effects by Leonurus sibiricus L. Extract in Human Breast Cancer MCF-7 Cells

Many studies have shown that phytochemicals in plants are effective in preventing and treating many cancers. Leonurus sibiricus L. (LS) is a plant widely used for the treatment of inflammatory conditions. However, the role of the anticancer effects of LS extract concerning breast cancers has not been examined. Our study investigated the antioxidant and anticancer effect of LS extract using MCF-7 cells (human breast cancer cell line). LS extract contained high total polyphenol (198.30 mg TAE/g) and total flavonoid (118.91 mg RE/g) contents as well as effective ABTS+ free radical scavenging capacity. LS extract at 0.1, 0.2, 0.4, and 0.8 mg/mL concentrations significantly inhibited the MCF-7 cells proliferation for 24 h and 48 h. Apoptotic bodies were observed in DAPI stained treated cells with LS extract under a fluorescence microscope. Furthermore, LS extract treatment showed increasing cleaved PARP protein expression while decreasing Bcl-2 and phospho-Akt levels. These results suggest that LS extract could be a promising chemopreventive agent for breast cancers.