Cancer cells are in a state of increased basal oxidative stress due to their aberrant growth. As a result, cancer cells have elevated levels of reactive oxygen species (ROS) compared to normal cells. This feature has been employed to develop a class of ROS-activated prodrugs that only become cytotoxic in the presence of ROS. To study this effect with the support of a team of undergraduate and graduate students, Prof. Peng received almost half a million dollars from the National Cancer Institute.

The effectiveness of ROS-activated prodrugs as monotherapy for cancer faces many challenges, including tumor heterogeneity, insufficient prodrug activation, difficulty in targeted drug delivery, lack of therapeutic durability, etc. Novel strategies are urgently needed to augment the efficacy and selectivity of ROS-activated prodrugs to a wide variety of cancer.