Anti-GPC3 antibody and cell-penetrating peptide CPP44 dual-ligand modified liposomes for targeted delivery of arsenic trioxide in the treatment of hepatocellular carcinoma

Arsenic trioxide (ATO), the active ingredient in Chinese arsenic, effectively inhibits hepatocellular carcinoma (HCC) cell growth, but its clinical application is limited by the lack of a targeted delivery system. Phosphatidylinositol proteoglycan 3 (GPC3) is specifically expressed in HCC, and CPP44 is a cell-penetrating peptide that targets HCC cells. Here, we developed a liposome incorporating ATO with dual surface modifications of anti-GPC3 antibody and CPP44. The system was firstly enriched and localised at the liver tumour site through passive targeting by EPR and active targeting by specific binding of anti-GPC3 antibody to GPC3 protein. CPP44 then facilitated ATO penetration into HCC cells. Specifically, we first employed computational modelling to demonstrate that the covalently-coupled antibody maintained its binding ability to the GPC3 antigen. Subsequent experimental assays revealed that Dl-ATO-Lp exhibited higher cell uptake rate and stronger tumour cell killing effect. In an HCC mouse model, Dl-ATO-Lp achieved effective tumour targeting, with a tumour inhibition rate of 63.43%. This dual-ligand liposome system enhances the targeted delivery and therapeutic efficacy of ATO, offering a promising direction for solid tumour therapy and advancing the clinical application of ATO.