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Combined Modality Therapy Based on Hybrid Gold Nanostars Coated with Temperature Sensitive Liposomes to Overcome Paclitaxel-Resistance in Hepatic Carcinoma.

ABSTRACT: In this study, we prepared gold nanostar (GNS) composite nanoparticles containing siRNA of cyclooxygenase-2(siCOX-2) that were modified by tumor targeting ligand 2-deoxyglucose (DG) and transmembrane peptide 9-poly-D-arginine (9R) to form siCOX-2(9R/DG-GNS). Paclitaxel loaded temperature sensitive liposomes (PTX-TSL) were surface-modified to produce PTX-TSL-siCOX-2(9R/DG-GNS) displaying homogeneous star-shaped structures of suitable size (293.93 nm ± 3.21) and zeta potentials (2.47 mV ± 0.22). PTX-TSL-siCOX-2(9R/DG-GNS) had a high thermal conversion efficiency under 808 nm laser radiation and a superior transfection efficiency, which may be related to the targeting effects of DG and increased heat induced membrane permeability. COX-2 expression in HepG2/PTX cells was significantly suppressed by PTX-TSL-siCOX-2(9R/DG-GNS) in high temperatures. The co-delivery system inhibited drug-resistant cell growth rates by ≥77% and increased the cell apoptosis rate about 47% at elevated temperatures. PTX-TSL and siCOX-2 loaded gold nanostar particles, therefore, show promise for overcoming tumor resistance.

SUBMITTER: Zhu H

PROVIDER: S-EPMC6969923 | biostudies-literature |

REPOSITORIES: biostudies-literature

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