Pu-18-N-butylimide-NMGA-GNP conjugate is effective against hepatocellular carcinoma

BACKGROUND Photodynamic therapy (PDT) is a new modality in the treatment of cancer. This study thus aims to examine whether the PDT is effective against in vivo hepatocellular carcinoma. METHODS In vivo efficacy of PDT on hepatocellular carcinoma was tested in xenografted mice with human hepatocellular carcinoma cell lines (Huh7) by utilizing a gold nanoparticles (GNPs) conjugate of new photosensitizer (PS), purpurin-18-N-butylimide-N-methyl-D-glucamine (Pu-18-N-butylimide-NMGA). The conjugate (PS-GNPs) was synthesized from the reaction between Pu-18-N-butylimide-NMGA and chloroauric acid (HAuCl4). Mice were arbitrarily assigned into one of three groups. First group received saline alone, second group received PS-GNPs alone, and the last group received both PS-GNPs and irradiation. PS-GNPs was injected directly into the tumor mass and irradiations were performed 24 hours after injection of PS-GNPs. RESULTS Tumor volume was significantly smaller in the group which received both PS-GNPs and irradiation compared with other two groups. Western blot and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay revealed that the group which received both PS-GNPs and irradiation showed larger amount of apoptotic protein and DNA fragmentation compared with other two groups. CONCLUSION This study suggests that Pu-18-N-butylimide-NMGA-GNP conjugate is an effective agent for PDT in the treatment of hepatocellular carcinoma.