Antitumor Effect of a Novel Photodynamic Therapy with Acetylated Glucose-conjugated Chlorin for Gastrointestinal Cancers

BACKGROUND/AIM:We previously synthesized a glucose-conjugated chlorin compound e6 (G-chlorin e6), and reported that it has very strong antitumor effects. The aim of the present study was to synthesize acetylated glucose-conjugated chlorin (AcN003HP) and evaluate its antitumor effect and excretion.MATERIALS AND METHODS:To evaluate the antitumor effect of AcN003HP, its IC50 was calculated as well as its accumulation in cancer cells was examined by flow cytometry. Confocal microscopy was used to observe the intracellular localization of AcN003HP. The excretion and antitumor effects of AcN003HP were also evaluated in vivo.RESULTS:AcN003HP showed stronger antitumor effects and accumulation into cancer cells compared to talaporfin sodium, a conventional photosensitizer. AcN003HP was localized in the endoplasmic reticulum. In a xenograft tumor mouse model, AcN003HP showed longer excretion time from the body than G-chlorin e6, and photodynamic therapy using AcN003HP showed very strong antitumor effects.CONCLUSION:The safety, improved controllability, and robust antitumor effects suggest AcN003HP as a good next-generation photosensitizer.