Mitochondrial and caspase pathways are involved in the induction of apoptosis by nardosinen in MCF-7 breast cancer cell line

Natural products isolated from plants provide a valuable source for expansion of new anticancer drugs. Nardosinen (4,9-dihydroxy-nardosin-6-en) is a natural sesquiterpene extracted from Juniperus foetidissima. Recently, we have reported the cytotoxic effects of nardosinen in various cancer cells. The aim of the current study was to investigate the anticancer features of nardosinen as well as its possible molecular mechanisms of the nardosinen cytotoxic effect on breast tumor cells. MTT assay showed that nardosinen notably inhibited cell proliferation in a dose-dependent manner in MCF-7 breast cancer cells. The growth inhibitory effect of nardosinen was associated with the induction of cell apoptosis, activation of caspase-6, increase of reactive oxygen species (ROS), and loss of mitochondrial membrane potentials (ΔΨm). Western blot assay following treatment with nardosinen showed that the expression levels of the Bax were significantly upregulated and the expression levels of the Bcl-2 were significantly down-regulated. Our results finally exhibited that nardosinen induces apoptosis in breast cancer cells via the mitochondrial and caspase pathways.