PCN224 Mediated Sono-Photodynamic Therapy Triggers Apoptosis through Multisite Damage in Hepa1-6 Cells

Background: Sono-photodynamic therapy (SPDT) is a novel anti-cancer strategy that has showed excellent preclinical anti-tumor effects by combining the advantage of photodynamic and sonodynamic therapy. Sensitizer is the most important ele-ment in SPDT, which directly influences the cytotoxicity of SPDT. This study investigated the effect of using sensitizer PCN 224 (PCN224-SPDT) in SPDT on mouse hepatocellular carcinoma Hepa1-6 (mouse hepatoma cells).Methods: Hepa1-6 cells were divided into a control group, PCN224 alone group (PCN224), ultrasound treatment alone group (US), PDT (photodynamic therapy) group (PCN224 + 5 J/cm2 laser), SDT (sonodynamic therapy) group (PCN224 + 1 W/cm2 ultrasound) and SPDT group (PCN224 + 5 J/cm2 laser + 1 W/cm2 ultrasound). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazole ammonium bromide (MTT) was used to detect cytotoxicity. The uptake and distribution of PCN224 in Hepa1-6 cells were determined by fluorescence staining. Flow cytometry was used to analyze intracellular reactive oxygen species (ROS) levels, cell membrane permeability, DNA damage, cell apoptosis levels, and mitochondrial membrane potential. Scanning trans-mission electron microscopy (SEM) was used to observe the changes in cell microstructure.Results: PCN224-SPDT induced severe damage to the cell membrane, mitochondrial and deoxyribonucleic acid (DNA), ulti-mately resulting in cell apoptosis.Conclusions: This work suggests that PCN224 is a new sensitizer for SPDT, and PCN224-SPDT can cause Hepa1-6 cells multisite damage and induce cell apoptosis via ROS production.