Targeted lung cancer therapy: preparation and optimization of transferrin-decorated nanostructured lipid carriers as novel nanomedicine for co-delivery of anticancer drugs and DNA

Figures & data

Figure 1 Schematic diagram of Tf-PTX-DNA-NLC.

Notes: Tf-PTX-DNA-NLC was prepared, firstly, by the formation of PTX-DNA-NLC, and then, Tf-PEG-PE was prepared and was placed onto the surface of PTX-DNA-NLC to obtain Tf-PTX-DNA-NLC.

Abbreviations: Tf-PTX-DNA-NLC, transferrin-decorated paclitaxel and deoxyribonucleic acid co-encapsulated nanostructured lipid carriers; PTX-DNA-NLC, paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf-PEG-PE, transferrin-conjugated polyethylene glycol-phosphatidylethanolamine.

Figure 2 TEM imaging of different NLC formulations.

Notes: PTX-DNA-NLC (A) had a spherical shape. Tf_5k-PTX-DNA-NLC (B) and Tf_10k-PTX-DNA-NLC (C) had slight, light coats on white, spherical-shaped particles.

Abbreviations: NLC, nanostructured lipid carriers; TEM, transmission electron microscopy; PTX-DNA-NLC, paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_5k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 5000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_10k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 10000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers.

Figure 3 The particle size and zeta potential of different NLC formulations.

Notes: The particle size (nm) and zeta potential (mV) of (A) blank NLC, (B) PTX-DNA-NLC, (C) Tf_5k-PTX-DNA-NLC, and (D) Tf_10k-PTX-DNA-NLC.

Abbreviations: NLC, nanostructured lipid carriers; Tf-PTX-DNA-NLC, transferrin-decorated paclitaxel and deoxyribonucleic acid co-encapsulated nanostructured lipid carriers; PTX-DNA-NLC, paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf-PEG-PE, transferrin-conjugated polyethylene glycol-phosphatidylethanolamine; Tf_5k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 5000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_10k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 10000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers.

Table 1 Characterization of different vectors

Vectors	PTX-DNA-NLC	Tf5k-PTX-DNA-NLC	Tf10k-PTX-DNA-NLC
DL (%)	92.2±1.9	90.3±1.6	90.9±2.7
EE (%)	87.1±2.1	85.4±2.9	82.8±3.1

Abbreviations: DL, DNA-loading ability; EE, encapsulation efficiency; PTX-DNA-NLC, paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_5k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 5000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_10k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 10000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers.

Figure 4 In vitro drug release profile of different NLC formulations.

Notes: The in vitro drug release profile of (A) Tf_10k-PTX-DNA-NLC, (B) Tf_5k-PTX-DNA-NLC, (C) PTX-DNA-NLC, and (D) Taxol^®.

Abbreviations: h, hours; NLC, nanostructured lipid carriers; PTX-DNA-NLC, paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_5k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 5000-phosphatidyle thanol-am ine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_10k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 10000-phosphatidylethanolamine-decorated paclitaxel- and deox yribonucleic acid-loaded nanostructured lipid carriers.

Figure 5 In vitro cytotoxicity of different NLC formulations.

Notes: Cell viability tests of Taxol^®, PTX-DNA-NLC, Tf_5k-PTX-DNA-NLC, and Tf_10k-PTX-DNA-NLC were performed at the PTX concentrations of 5, 10, 20, 50, and 100 μM. Blank NLC, blank Tf_5k-NLC, and blank Tf_10k-NLC were also analyzed as contrast. Tf_5k-PTX-DNA-NLC had the highest cytotoxic effect compared with other formulations (P<0.05).

Abbreviations: PTX, paclitaxel; NLC, nanostructured lipid carriers; PTX-DNA-NLC, paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_5k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 5000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_10k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 10000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers.

Figure 6 Effects of different NLC formulations on tumor growth in vivo.

Notes: Tumor growth was suppressed to some extent after administration of Taxol^®. Tf_5k-PTX-DNA-NLC exhibited significantly better tumor regression than Tf_10k-PTX-DNA-NLC and PTX-DNA-NLC (P<0.05).

Abbreviations: NLC, nanostructured lipid carriers; PTX-DNA-NLC, paclitaxel-and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_5k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 5000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_10k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 10000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers.

Figure 7 Flow cytometry analysis of in vitro gene transfection.

Notes: Significantly higher transfection efficiency was observed in Tf_5k-PTX-DNA-NLC and Lipo-DNA than other formulations at both 36 hours and 72 hours after transfection (P<0.05). At 36 hours, the transfection efficiency of Tf_5k-PTX-DNA-NLC was lower than Lipo-DNA complexes (P<0.05), while higher transfection efficiency was obtained at 72 hours when compared with Lipo-DNA (P<0.05). Tf_10k-PTX-DNA-NLC did not exhibit good in vitro gene transfection ability at either 36 or 72 hours.

Abbreviations: h, hours; NLC, nanostructured lipid carriers; DNA, deoxyribonucleic acid; Lipo-DNA, Lipofectamine^®-DNA complexes; Tf_5k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 5000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_10k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 10000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers.

Figure 8 Flow cytometry analysis of in vivo gene transfection.

Notes: Significantly higher transfection efficiency was observed in Tf_5k-PTX-DNA-NLC and Lipo-DNA than other formulations at both 36 hours and 72 hours after transfection (P<0.05). At 36 hours, the transfection efficiency of Tf_5k-PTX-DNA-NLC was similar to that of Lipo-DNA complexes, while higher transfection efficiency was obtained at 72 hours when compared with Lipo-DNA (P<0.05). Tf_10k-PTX-DNA-NLC did not exhibit good in vivo gene transfection ability at either 36 or 72 hours; the data were indicative of poorer efficiency than data obtained from non-decorated PTX-DNA-NLC.

Abbreviations: h, hours; DNA, deoxyribonucleic acid; NLC, nanostructured lipid carriers; Lipo-DNA, Lipofectamine^®-DNA complexes; PTX-DNA-NLC, paclitaxel-and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_5k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 5000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers; Tf_10k-PTX-DNA-NLC, transferrin-conjugated polyethylene glycol 10000-phosphatidylethanolamine-decorated paclitaxel- and deoxyribonucleic acid-loaded nanostructured lipid carriers.