Cancer cell lines involving cancer stem cell populations respond to oxidative stress

Cancer cells may be more prone to the accumulation of reactive oxygen species (ROS) than normal cells; therefore increased oxidative stress can specifically kill cancer cells including cancer stem cells (CSCs). In order to generate oxidative stress in various cancer cell lines including A549, G361 and MCF-7, cultured cells were exposed to H₂O₂. Incubation of cancer cells with H₂O₂ results in concentration-dependent cell death in A549 and G361-7 cells, whereas MCF-7 cells showed higher sensitivity even at a lower H₂O₂ concentration. H₂O₂ treatment decreased the number of cells in G2/M phase and increased the number of apoptotic cells. Both CD24 negative/CD44 positive cells and CD146 positive cells were found to be present in all tested cancer cell lines, indicating that CSC populations may play role in the cellular response to oxidative stress. This study showed that inducing oxidative stress through ROS can offer a promising approach for anti-cancer therapy.