Background: The phenylboronic acid-functionalized polyamidoamine (PP) was employed as a gene carrier for Dz13 delivery, inducing an obvious anticancer response.
Materials and methods: The Dz13 condensation ability of PP was evaluated through gel retardation assay. The cellular uptake mechanism of PP/Dz13 nanoparticles was studied using confocal laser scanning microscope and flow cytometer. The inhibition ability of cell proliferation, migration and invasion was investigated through MTT assay, flow cytometry, wound healing and Transwell migration assays, using hepatocarcinoma cell line HepG2 as a model. Finally, Western blotting analysis was used to detect the signaling pathway associated with the inhibition of cell apoptosis and migration induced by Dz13 delivery.
Results: The carrier PP could efficiently condense Dz13 into stable nanoparticles at mass ratios of >1.5. The hydrodynamic diameter and zeta potential of PP/Dz13 nanoparticles were measured to be 204.77 nm and +22.00 mV at a mass ratio of 10.0, respectively. The nanoparticles could realize an efficient cellular uptake in sialic acid-dependent endocytosis manner. Moreover, the nanoparticles exhibited an obvious antiproliferation effect through the induction of cell apoptosis and cell cycle arrest due to the cleavage of c-Jun  mRNA. Besides, the suppression of cell migration and invasion could be achieved after the PP/Dz13 transfection, attributing to the decreased expression level of MMP-2  and MMP-9 .
Conclusion: The PP provided a potential delivery system to achieve the tumor-targeting gene therapy.
Keywords: phenylboronic acid, polyamidoamine, DNAzyme, gene therapy, antiproliferation effect, antimigration effect