Thermodynamic
therapy (TDT), one that uses heat to activate thermosensitizers
and produce reactive oxygen species (ROS), has recently emerged as
an attractive approach for cancer therapy. However, the development
of safe and efficient thermosensitizers for TDT remains a big challenge.
Here, we have found that artesunate (ARS) could produce ROS upon heating.
Based on this interesting result, we have designed and prepared a
pH-sensitive liposomal nanoplatform (ICG-ARS@NPs) composed
of indocyanine green (ICG) and ARS for photoinduced TDT as well as
photothermal therapy (PTT). Under the slightly acidic conditions in
tumor tissues, the pH-sensitive liposomal ICG-ARS@NPs were able to release their drug cargos. Upon near-infrared irradiation,
the photothermal agent ICG generated in situ hyperthermia and triggered
the thermal sensitizing activity of ARS to produce ROS, resulting
in damage to cancer cells and tumor tissues. The heat-induced ROS
generation of ARS was also confirmed both in vitro and in vivo. In
addition, because of their specific tumor targeting and synergistic
photothermal and thermodynamic effects, ICG-ARS@NPs exhibited
highly efficient anticancer therapeutic efficacy in H22 tumor-bearing
mice. We believe that this work will promote the exploration of TDT
for cancer therapy as well as the application of the old drug, artemisinin.