Screening active anti-breast cancer compounds from cortex magnolia officinalis by MCF-7 cell membrane chromatography coupled with UHPLC-ESI-MS/MS

Breast cancer is one of the most frequent malignant tumors in females. Extracts from Cortex Magnolia Officinalis (CMO) have shown the ability to inhibit the growth of breast cancer cells. In the present study, we developed MCF-7 cell membrane chromatography (CMC) combined with a UHPLC-ESI-MS/MS method to screen and identify the active components from the extract of CMO. Sorafenib and dexamethasone acetate were used as positive and negative control drugs, respectively, to investigate the suitability of this system. Under optimum experimental conditions, two components showed strong retention characteristics on the MCF-7 cell membrane chromatographic column. These compounds were identified as magnolol and honokiol by UHPLC-ESI-MS/MS. Cytotoxicity assay and Hoechst 33258 staining were done to investigate the anti-proliferative activity of the two compounds. The MTT results showed that MCF-7 cell viability decreased gradually in a dose-dependent manner during 48 h. The IC₅₀ of magnolol and honokiol were 85.4 μM and 58.1 μM, respectively. After Hoechst 33258 staining, the cells were observed with bright blue nuclei due to karyopyknosis and chromatin condensation. The screening results showed that both magnolol and honokiol were promising active components of CMO extract having an inhibitory effect on MCF-7 cell growth. This two-dimensional method CMC-UHPLC-ESI-MS/MS could have potential utility for screening target components from traditional Chinese medicines.