A novel MUC1 aptamer-modified PLGA-epirubicin-PβAE-antimir-21 nanocomplex platform for targeted co-delivery of anticancer agents in vitro and in vivo

Conventional chemotherapy suffers from several drawbacks, including toxic side effects together with the development of resistance to the chemical agents. Therefore, exploring alternative therapeutic approaches as well as developing targeted delivery systems are in demand. Oligonudeotide-based therapy has emerged as a promising and alternative procedure for treating malignancies involving gene-related diseases. In the current study, a targeted delivery system was designed to target cancer cells based on two biocompatible polymers of poly (beta amino ester) (P beta AE) and poly (n, L-lactide-co-glycolide) (PLGA). In this system, antimir-21 as an inhibitor of microRNA-21 (miR-21) which is an oncomiR overexpressed in several human cancers was condensed with P beta AE polymer and then PLGA was electrostatically deposited on this complex and provided a reservoir for positively charged drug, epirubicin (Epi). At the final stage, MUC1 aptamer as a targeting agent was covalently attached to the nanoparticles for selectively guided therapeutic delivery. The obtained results demonstrated that the fabricated MUC1 aptamer-modified nanocomplex could efficiently be internalized into MCF7 (human breast carcinoma cell) and C26 (murine colon carcinoma cell) cells through interaction between MUC1 aptamer and its receptor on the surfaces of these cell lines and decline cell viability in these cells but not in CHO cells (Chinese hamster ovary cell) as nontarget cells (MUC1 negative cells). The safety of PLGA-Epi-P beta AE-antimir-21 nanocomplex and synergetic effect of Epi and antimir-21 in reducing cell viability of target cells were confirmed by treating MCF-7 and CHO cells with nanocomplex and MUC1 aptamer-modified nanocomplex. Moreover, it was demonstrated that MUC1 aptamer-modified nanocomplex could remarkably inhibit tumor growth in tumor bearing mice compared with Epi alone.