Ethyl acetate extract of Clausena excavata induces growth inhibition of non-small-lung cancer, NCI-H460, cell line via apoptosis

Context: Clausena excavata Burm. f is a plant used in folklore medicine for the treatment of various ailments in South East Asia. The plant parts contain chemical components that are cytotoxic to many cancer cells. Objective: The study investigated the cytotoxic effects of ethyl acetate, methanol and chloroform C. excavata leaf extracts on the non-small-lung cancer, NCI-H460, cell line. Methods: Based on the 3-(4,5-dimethylthiazol-2-yl)-2,5,-diphenyltetrazolium bromide (MTT) assay, among extracts, ethyl acetate C. excavata leaf extract (EACE) was the most potent anti-NCI-H460 cells, with IC50 value of 47.1 ± 6.1 μg/ml. The effects of EACE on NCI-H460 cells were also determined by clonogenic, 4', 6-diamidino-2-phenylindole (DAPI), and annexin-V-fluorescein isothiocyanate/propidium iodide-PI flow cytometric assays. Reactive oxygen species (ROS) production and apoptotic gene expressions was determined via flow cytometry and real-time quantitative PCR, respectively. Results: EACE-treated NCI-H460 cells after 48 h underwent apoptosis as evident by loss of cell viability, cell shrinkage, and chromatin condensation. The results also showed EACE mediated increase in ROS production by the NCI-H460 cells. After 48 h treatment, EACE increased the pro-apoptotic BAX and decreased the anti-apoptotic Bcl-2, Survivin and c-Myc gene expressions. Conclusions: EACE is a potential anti-lung cancer by increasing cancer cell ROS production and apoptosis.