Effective tumor vessel barrier disruption mediated by perfluoro-N-(4-methylcyclohexyl) piperidine nanoparticles to enhance the efficacy of photodynamic therapy

Background: Currently, limited tumor drug permeation, poor oxygen perfusion and immunosuppressive microenvironments are the most important bottlenecks that significantly reduce the efficacy of photodynamic therapy (PDT). The main cause of these major bottlenecks is the platelet activation maintained abnormal tumor vessel barriers. Thus, platelet inhibition may present a new way to most effectively enhance the efficacy of PDT. However, to the best of our knowledge, few studies have validated the effectiveness of such a way in enhancing the efficacy of PDT both in vivo and in vitro. In this study, perfluoro-N-(4-methylcyclohexyl) piperidine-loaded albumin (PMP@Alb) nanoparticles were discovered, which possess excellent platelet inhibition ability. After PMP@Alb treatment, remarkably enhanced intra-tumoral drug accumulation, oxygen perfusion and T cell infiltration could be observed owing to the disrupted tumor vessel barriers. Besides, the effect of ICG@Lip mediated PDT was significantly amplified by PMP@Alb nanoparticles. It was demonstrated that PMP@Alb could be used as a useful tool to improve the efficacy of existing PDT by disrupting tumor vessel barriers through effective platelet inhibition.