Multifunctional tumor-targeting nanocarriers based on hyaluronic acid-mediated and pH-sensitive properties for efficient delivery of docetaxel.

PURPOSE

The objective of this work was to develop a multifunctional tumor-targeting nanocarrier based on the mechanism of CD44-mediated endocytosis and pH-induced drug release to improve the therapeutic efficacy of docetaxel (DTX).

METHODS

Hyaluronic acid-coated docetaxel-loaded cholesteryl hemisuccinate vesicles (HA-CHEMS vesicles) were prepared. The physiochemical properties and pH-dependent drug release of HA-CHEMS vesicles were evaluated. The HA-CHEMS vesicles were investigated for CD44-mediated internalization and in vitro cell viability using MCF-7,A549 and L929 cells.In addition,tissue distribution as well as antitumor efficacy was also evaluated in MCF-7 tumor-bearing mouse model.

RESULTS

The particle size and zeta potential of HA-CHEMS vesicles were 131.4 ± 6.2 nm and -13.3 ± 0.04 mV,respectively. The in vitro drug release results demonstrated a pH-responsive drug release under different pH conditions. In vitro cell viability tests suggested that the encapsulation of DTX in HA-CHEMS vesicles led to more than 51.6-fold and 46.3-fold improved growth inhibition in MCF-7 and A549 cell lines,respectively compared to Taxotere®. From the cell uptake studies,the coumarin 6-loaded HA-CHEMS vesicles enhanced intracellular fluorescent intensity in the CD44-overexpressing cell line (MCF-7). Biodistribution studies revealed selective accumulation of HA-CHEMS vesicles in the MCF-7 bearing BalB/c nude mice as a result of passive accumulation and active targeting (CD44-mediated endocytosis). Compared to Taxotere®,HA-CHEMS vesicles exhibited higher antitumor activity by reducing tumor volume (P < 0.05) and drug toxicity,demonstrating the success of the multifunctional targeting delivery.

CONCLUSIONS

This work corresponds to the preparation of a multifunctional tumor-targeted delivery system. Our investigation shows that hyaluronan-bearing docetaxel-loaded cholesteryl hemisuccinate vesicles (HA-CHEMS vesicles) is a highly promising therapeutic system,leading to tumor regression after intravenous administration without visible toxicity.