Caspase-Dependent Apoptosis Induced by Simarouba Glauca on Human Non-Small-Cell Lung Cancer, A549 Cells

BACKGROUND: The leaves of Simarouba glauca (S. glauca) have been used as a potential source of anticancer agents in traditional medicine. Attempts have been made to isolate anticancer agents from the leaves of S. glauca. The objective of the present study was to demonstrate the anticancer and apoptotic effect of the leaf extract of petroleum ether (LPE) on human non-small-cell lung cancer A549 cells. METHODS: MTT assay was used to investigate the effect of LPE on the viability of A-549 cells. The apoptotic effect of human lung cancer cells was evaluated using fluorescence staining, acridine orange/ ethidium bromide staining, Hoechst staining, flow cytometry analysis, annexin V staining, and caspase assay. RESULTS: The results showed a direct correlation between the dose and the rate of cytotoxicity. Fluorescence staining revealed apoptotic features, such as blebbing and chromatin condensation. Flow cytometry analysis and annexin V staining revealed phosphatidyl serine externalization. Caspase assay confirmed that the extract inhibited cell death. Caspase 3 expressions indicated that the cell death occurred either through the mitochondrial pathway or the death receptor. CONCLUSIONS: The study revealed that the LPE induced the apoptosis of human non-small-cell lung cancer, A549 cells, either through mitochondrial or death receptor pathway.