A glutathione activatable pro-drug-photosensitizer for combined chemotherapy and photodynamic therapy

During cancer treatment, chemotherapeutic drugs always result in severe side-effects and drug resistance. Therefore, combining cheomtherapy with other therapeutic modalities, such as photodynamic therapy (PDT) and designing an activable platform is promising for precise and efficient anticancer treatment. Herein, we report a “pro-drug-photosensitizer” agent, LMB-S-CPT, bearing a disulfide bond as the glutathione (GSH)-activatable linker. LMB-S-CPT can be selectively activated by GSH to release activated drug, camptothecin (CPT), for chemotherapy and activated photosensitizer, methylene blue (MB), for PDT. LMB-S-CPT exhibits excellent tumor-activatable performance when injected into tumor-bearing mice, as well as specific cancer therapy with negligible toxic side effects. The activatable pro-drug-photosensitizer offers a new strategy for chemo-photodynamic therapy and displays precise, selective and excellent antitumor effect.