Nanoparticles comprising micheliolide (MCL) or derivatives thereof, and optionally additional therapeutic agents, such as chemotherapeutic agents, are described. Also described are methods of treating diseases, such as cancer, comprising the use of combinations of MCL or a derivative thereof with X-ray irradiation and/or other therapeutic agents, such as immune checkpoint inhibitors. The use of the combinations can provide synergistic anticancer therapeutic efficacy, for example, as the MCL or derivative thereof can both sensitize cancer cells to therapy and target resistant cancer stem cells (CSCs) for selective cell death.
