Elesclomol-induced activation of a HOCl-responsive phototheranostic agent for enhanced therapy and imaging

A hypochlorous acid (HOCl)-sensitive, mitochondria-targeting hemicyanine-based type-I photosensitizer (CyPO) was developed and employed in a synergistic therapy using elesclomol-Cu(II) complex, which serves both as a potent anticancer drug and a source of HOCl for effective activation of CyPO. Treating HeLa cancer cells with elesclomol-Cu(II) and CyPO significantly improved the therapeutic outcome of CyPO compared to single mode chemotherapy and photodynamic therapy (PDT). Furthermore, the fluorescence imaging capacity of CyPO is enhanced when it is combined with the elesclomol-Cu(II) complex. This study marks the first example of a elesclomol-induced PDT action implemented in a synergistic and integrated manner, showcasing a highly promising approach for enhancing the therapeutic efficacy.