5-Boronopicolinic acid-functionalized polymeric nanoparticles for targeting drug delivery and enhanced tumor therapy

Abstract

Strong specificity for cancer cells is still the main challenge to deliver drugs for the therapy of cancer. Herein, we developed a convenient strategy to prepare a series of 5-boronopicolinic acid (BA) modified tumor-targeting drug delivery systems (T-DDSs) with strong tumor targeting function. An anti-tumor drug of camptothecin (CPT) was encapsulated into poly(lactide-co-glycolide)-g-polyethylenimine (PLGA-PEI) to form drug-loaded nanoparticles (NP/CPT). Then, the surface of NP/CPT was coated by BA with different polymer and BA molar ratios of 1:1, 1:5, 1:10 and 1:20 via electrostatic interaction to obtain T-DDSs with enhanced biocompatibility and specificity for tumor cells. The introduced BA can endow drug-loaded NPs with high targeting ability to tumor cells because of the overexpression of sialic acids (SA) in tumor cells, which possessed strong interaction with BA. Those T-DDSs exhibited good biocompatibility according to the results of MTT assay, hemolysis test and cellular uptake. Moreover, they were capable of decreasing the viability of breast cancer cell line 4T1 and MCF-7 cells with no obvious cytotoxicity for endothelial cells. Especially, T-DDS with 1:20 molar ratio displayed much higher cellular uptake than other groups, and also exhibited highly efficient in vivo anti-tumor effect. The significantly high targeting function and biocompatibility of T-DDSs improved their drug delivery efficiency and achieved good anti-tumor effect. The BA decorated T-DDSs provides a simple and robust strategy for the design and preparation of DDSs with good biocompatibility and strong tumor-specificity to promote drug delivery efficiency.