Apoptosis-inducing photodynamic therapy via dual-wavelength responsive ICG/Ce6 incorporated mesoporous silica nanoparticles in prostate cancer cells

Photodynamic therapy (PDT) destroys cancer cells by photoactivation of photosensitive agents with minimal side effects on healthy tissue. Due to its limitations, using nanoparticles is a promising strategy to increase the efficacy of PDT. Mesoporous silica nanoparticles (MSN) are advantageous candidates for delivering the photosensitizer with their biocompatibility, pore structure, and large surface area. In this study, a novel design of MSN is produced by incorporating indocyanine green (ICG) and chlorin e6 (Ce6) into its structure. A dual-laser system is set up with 655- and 808-nm diode lasers for the PDT applications on prostate cancer cells (PC3). After the applications, the action mechanism is investigated via cell viability, cell staining, mechanistic, and qRT-PCR analyses. 100 μg/ml of nanoparticle concentration shows the highest anticancer PDT activity with a rate of 75% decrease in cell viability and exhibits minimal side-effect on healthy cells. Besides the overexpression of the Caspase 3 gene, all mechanistic and staining analyses support the apoptotic cell death mechanism of PDT in the presence of this nanoparticle. This study shows that PDT mediated by the novel design of MSN is a promising treatment for lethal cancer types and will enlighten future studies.