Reactive oxygen species contribute to TRAIL receptors upregulation; the mechanism for PH II-7 augmenting TRAIL induced apoptosis in leukemia cells

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can selectively induce apoptosis in cancer cells and is verified to be effective in various cancers. However, a variety of cancer cells are found to be resistant to TRAIL and the mechanisms are largely unknown. Moreover, multidrug resistance to traditional chemotherapeutic agents still remains a tough problem in clinical practice. Fortunately, our previous work proved the ability of PH II-7 in overcoming MDR phenotype through reactive oxygen species production in K562 and its MDR counterpart K562/A02 cells. Additionally, we further explored its potential in augmenting TRAIL induced apoptosis in cancer cells with various tissue origins. Our results showed PH II-7 up-regulated DR4/DR5 expression and augment TRAIL cytotoxicity through reactive oxygen species production, which provide a solid foundation for TRAIL in combination with PH II-7 in future clinical application.