Seed Oil ofBrucea javanicaInduces Cell Cycle Arrest and Apoptosis via Reactive Oxygen Species-Mediated Mitochondrial Dysfunction in Human Lung Cancer Cells

Brucea javanica oil (BJO), a traditional herbal medicine extracted from the seeds of B. javanica, has been clinically used to treat non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) in combination with chemotherapy or radiotherapy in China. However, how BJO exerts this antitumor effect is still largely unknown. Here, effects of BJO on the growth of NSCLC and SCLC cell lines were investigated by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenytetrazolium Bromide (MTT) assay, and the results showed that BJO inhibited the proliferation of A549 cells (NSCLC) and H446 cells (SCLC). Further studies revealed that BJO induced G0/G1 arrest partly via regulating p53 and cyclin D1 in these two cell lines. BJO also has pro-apoptotic effect on H446 and A549 cells through mitochondria/caspase-mediated pathway, which was initiated by the accumulation of intracellular reactive oxygen species (ROS). These findings thus revealed the molecular mechanisms underlying the antitumor effect of BJO on SCLC and NSCLC, which may benefit the further clinical application of BJO.