fig4

Figure 4. (A) Schematic illustration of the formation of pH-sensitive nanosystems (Ac-α-CD NP); (B) The cell viability of MDA-MB-231 cells treated with different doses of PTX, PLGA NP, and Ac-α-CD NP (^**P < 0.01). This figure is quoted with permission from He et al.^[74]; (C) Schematic illustration of the antitumor progress of Ac-α-CD NP in MCF-7/ADR cells; (D) The P-gp expression level; and (E) the accumulation of DOX with different doses of Ac-α-CD NP in MCF-7/ADR cells (^*P < 0.05, ^**P < 0.01). This figure is quoted with permission from Shi et al.^[75]. CD: Cyclodextrin; DOX: doxorubicin; NP: nanoparticle; PTX: paclitaxel.