Cell viability was determined by MTT assay and apoptosis assayed using flow cytometry. Differential expression of 84 genes commonly involved in breast cancer carcinogenesis was assessed by real-time PCR using the Human Breast Cancer RT2 Profiler PCR Array.
MCF-7 and MDA-MB-231 cells were treated with embelin (0–25 μM) for 24 and 96 h. Embelin exhibited time and dose dependence in both cell lines and was more potent in inhibiting MDA-MB-231 cell proliferation compared to MCF-7 cells. IC50 for embelin in MDA-MB-231 cells was ∼4.45 μM and 3.28 μM at 24 h and 96 h, respectively. In contrast, IC50 for embelin in MCF-7 cells was ∼6.04 μM and 4.51 μM at 24 h and 96 h, respectively. Embelin (50 μM) induced apoptosis and activated caspase 3 activity in both cell lines when exposed for 72 h. Treatment of MDA-MB-231 cells with embelin (10 μM) for 24 h resulted in significant differential expression of 27 genes commonly involved in breast cancer carcinogenesis.
Our findings show that embelin inhibits cell proliferation, induces apoptosis and alters expression of breast cancer focused genes in MCF-7 and MDA-MB-231 cells. Based on RT2-PCR array analysis, embelin down-regulated expression of pivotal oncogenes. This knowledge could be beneficial in the development of effective embelin-based therapies for treating breast cancer.