Dual-purposing disulfiram for enhanced chemotherapy and afterglow imaging using chlorin e6 and semiconducting polymer...

Rationale: One of the main challenges in chemotherapy is achieving high treatment efficacy while minimizing adverse events. Fully exploiting the therapeutic potential of an old drug and monitoring its effects in vivo is highly valuable, but often difficult to achieve. Methods: In this study, by encapsulating disulfiram (DSF) approved by US Food and Drug Administration, semiconducting polymer nanocomplex (MEHPPV), and Chlorin e6 into a polymeric matrix F127 via nanoprecipitation method, a nanosystem (FCMC) was developed for afterglow imaging guided cancer treatment. The characteristics, stability as well as the ability of singlet oxygen (¹O₂) production of FCMC were first carefully examined. Then, we studied the mechanism for enhanced anti-cancer efficiency and afterglow luminescence in vitro. For experiments in vivo, 4T1 subcutaneous xenograft tumor mice were injected with FCMC via the tail vein every three days and the antitumor effect of FCMC was evaluated by monitoring tumor volume and body weight every three day. Results: The nanosystem, which combines DSF with Ce6, can generates abundant ¹O₂ that enhances the antitumor activity of DSF. The in vivo results show that FCMC-treated group exhibits an obviously higher tumor-growth inhibition rate of 67.89% after 15 days of treatment, compared to the control group of F127@MEHPPV-CuET. Moreover, Ce6 also greatly enhances the afterglow luminescence intensity of MEHPPV and promotes the redshift of the afterglow emission towards the ideal near-infrared imaging window, thereby enabling efficient afterglow tumor imaging in vivo. Conclusions: This multifunctional nanoplatform not only improves the anticancer efficacy of DSF, but also enables monitoring tumor via robust afterglow imaging, thus exhibiting great potential for cancer therapy and early therapeutic outcome prediction.