Xanthatin Inhibits Non-Small Cell Lung Cancer Proliferation by Breaking the Redox Balance.

Lung cancer is the cancer with the highest mortality, and non-small cell lung cancer (NSCLC) accounts for more than 80%. Tumor cells often have high reactive oxygen species (ROS) and antioxidant capacity. Redox balance is very important for tumor. The decline of antioxidant capacity and excessive ROS will induce the death of tumor cells. Destroying the redox balance of tumor cells is a promising tumor treatment strategy. Xanthatin is an active sesquiterpene lactone isolated from Xanthium strumarium L. We observed that xanthatin induced the up regulation of mitochondrial ROS and mitochondrial damage. Meanwhile, our results showed that xanthatin could inhibit system x(c)(-) and reduce glutathione (GSH) synthesis. Antioxidant GSH and N-acetyl- l-cysteine (NAC) significantly reversed cell proliferation inhibition and apoptosis induced by xanthatin. beta-Mercaptoethanol (beta-ME) which can avoid inhibition of system x(c)(-) can also reverse the inhibition of cell proliferation induced by xanthatin, si-SLC7A11 was the opposite. Based on these results, we believe that the inhibition of xanthatin on the proliferation of NSCLC cells may be related to breaking the intracellular redox balance. Our data suggest that xanthatin is a promising antitumor candidate for the treatment of NSCLC.