Controlled gene and drug release from a liposomal delivery platform triggered by X-ray radiation

Abstract

Liposomes have been well established as an effective drug delivery system, due to simplicity of their preparation and unique characteristics. However conventional liposomes are unsuitable for the on-demand content release, which limits their therapeutic utility. Here we report X-ray-triggerable liposomes incorporating gold nanoparticles and photosensitizer verteporfin. The 6 MeV X-ray radiation induces verteporfin to produce singlet oxygen, which destabilises the liposomal membrane and causes the release of cargos from the liposomal cavity. This triggering strategy is demonstrated by the efficiency of gene silencing in vitro and increased effectiveness of chemotherapy in vivo. Our work indicates the feasibility of a combinatorial treatment and possible synergistic effects in the course of standard radiotherapy combined with chemotherapy delivered via X-ray-triggered liposomes. Importantly, our X-ray-mediated liposome release strategy offers prospects for deep tissue photodynamic therapy, by removing its depth limitation.

Abstract

X-ray radiation has excellent tissue penetration depth, making it a useful trigger for deep tissue cancer therapy. Here, the authors design X-ray triggered drug/gene-loaded liposomes by embedding photosensitizers and gold nanoparticles in the liposome bilayer, and demonstrate their efficacy in cancer and gene therapy.