Figure 1.
Schematic of the PPG fabrication and MDR reversion.
Figure 2.
Fabrication and characterization of PPG.
(A) AFM images of GO (left) and PPG (right). (B) Zeta-potential analysis of GO, PSS/GO and PPG.
Figure 3.
Fabrication of PPGADR, anti-miR-21PPG and anti-miR-21PPGADR.
(A) UV-Vis spectra of ADR, PPG, PPGADR and anti-miR-21PPGADR in aqueous solution; (B) Electrophoretic mobility of anti-miR-21 with PPGADR at different volume ratios.
Figure 4.
Characterization by flow cytometry of PPG co-delivering anti-miR-21 and ADR.
MCF-7/ADR cells were incubated with PPGADR, FAM-anti-miR-21PPG, FAM-anti-miR-21PPGADR at 37°C for 4 h and harvested for flow cytometry analysis. Cells treated with blank PPG served as a control.
Figure 5.
In vitro cellular cytotoxicity.
Relative survival rate of MCF-7 cells (A) and MCF-7/ADR cells (B) after being treated with ADR, anti-miR-21PPG, PPGADR and anti-miR-21PPGADR for 24 h. Untreated MCF-7 and MCF-7/ADR cells were served as control in each experiment. Data are means ± SD for three separate experiments, *P<0.05, **P<0.01, ***P<0.001.
Figure 6.
In vitro miR-21 and ABCB1 expression.
Real time PCR analysis of relative miR-21 expression (A) and ABCB1 expression (B) in MCF-7 and MCF-7/ADR cells treated with ncRNAPPG and anti-miR-21PPG. The expression of miR-21 and ABCB1 in MCF-7 cells treated with ncRNAPPG were arbitrarily set as 1. Data are means ± SD for three separate experiments, ***P<0.001.
Figure 7.
ADR accumulation and uptake mechanism in MCF-7/ADR cells.
(A) ADR accumulation in MCF-7/ADR cells incubated with ADR, PPGADR or anti-miR-21PPGADR for 24 h. The ADR concentration was determined by HPLC and normalized to total cell protein. Data are shown as the mean ± SD, n = 3. (B) Cellular uptake efficiency of ADR in MCF-7/ADR incubation with anti-miR-21PPGADR at 37°C after treated with sucrose, at 37°C after treated with indomethacin and at 4°C. The uptake efficiency of ADR in MCF-7/ADR incubation with anti-miR-21PPGADR at 37°C without any treatment was set as control. Data are means ± SD for three separate experiments, **P<0.01, ***P<0.001.