Ligustrazine induces apoptosis of breast cancer cells in vitro and in vivo

Introduction: Ligustrazine, the active ingredient present in Umbelliferae plant roots used in Chinese medicine, plays a vital role in reversing multidrug resistance in tumors. This study aims to investigate its anticancer activity and underlying mechanisms in human breast cancer cells in vitro and in vivo. Materials and Methods: Human breast cancer cell line MDA-MB-231 was incubated with different concentrations of ligustrazine. The cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay; and cell apoptosis and cell cycle were assessed by flow cytometry. Subcutaneous MDA-MB-231 xenograft tumors were established in nude BALB/c mice. Ligustrazine was intraperitoneally administered. The tumor growth was monitored. Results: In vitro, ligustrazine inhibited cell survival in a dose-and time-dependent manner, and induced apoptosis, as indicated by a dramatic increase in sub-G0/G1 cells. The in vivo results were consistent with the in vitro ones: Administration of ligustrazine substantially inhibited tumor growth, which also indicated that ligustrazine inhibited proliferation of MDA-MB-231 cells in vitro. Conclusions: Ligustrazine causes apoptotic death and tumor regression in human breast cancer cells in vitro and in vivo models.