Background: Hepatocellular carcinoma (HCC), arising from hepatocytes, is the most common primary liver cancer. It is urgent to develop novel therapeutic approaches to improve the grim prognosis of advanced HCC. 10-hydroxycamptothecin (HCPT) has good antitumor activity in cells; however, its hydrophobicity limits its application in the chemotherapy of HCC. Recently, nanoscale porphyrin metal-organic frameworks have been used as drug carriers due to their low biotoxicity and photodynamic properties.
Methods: Nanoscale zirconium porphyrin metal-organic frameworks (NMOFs) were coated with arginine-glycine-aspartic acid (RGD) peptide to prepare NMOFs-RGD first. The HepG2 cell line, zebrafish embryos and larvae were used to test the biotoxicity and fluorescence imaging capability of NMOFs-RGD both in vitro and in vivo. Then, NMOFs were used as the skeleton, HCPT was assembled into the pores of NMOFs, while RGD peptide was wrapped around to synthesize a novel kind of nanocomposites, HCPT@NMOFs-RGD. The tissue distribution and chemo- and photodynamic therapeutic effects of HCPT@NMOFs-RGD were evaluated in a doxycycline-induced zebrafish HCC model and xenograft mouse model.
Results: NMOFs-RGD had low biotoxicity, good biocompatibility and excellent imaging capability. In HCC-bearing zebrafish, HCPT@NMOFs-RGD were specifically enriched in the tumor by binding specifically to integrin α_vβ₃ and led to a reduction in tumor volume. Moreover, the xenografts in mice were eliminated remarkably following HCPT@NMOFs-RGD treatment with laser irradiation, while little morphological change was found in other main organs.
Conclusion: The nanocomposites HCPT@NMOFs-RGD accomplish tumor targeting and play synergistic chemo- and photodynamic therapeutic effects on HCC, offering a novel imaging-guided drug delivery and theranostic platform.
Keywords: zirconium porphyrin metal-organic frameworks, 10-hydroxycamptothecin, hepatocellular carcinoma, chemotherapy, photodynamic therapy