Mixed Nanosized Polymeric Micelles as Promoter of Doxorubicin and miRNA-34a Co-Delivery Triggered by Dual Stimuli in Tumor Tissue

作者:Salzano Giuseppina; Costa Daniel F; Sarisozen Can; Luther Ed; Mattheolabakis George; Dhargalkar Pooja P; Torchilin Vladimir P*
来源:Small, 2016, 12(35): 4837-4848.
DOI:10.1002/smll.201600925

摘要

Dual stimuli-sensitive mixed polymeric micelles (MM) are developed for co-delivery of the endogenous tumor suppressor miRNA-34a and the chemotherapeutic agent doxorubicin (Dox) into cancer cells. The novelty of the system resides in two stimuli-sensitive prodrugs, a matrix metalloproteinase 2 (MMP2)-sensitive Dox conjugate and a reducing agent (glutathione, GSH)-sensitive miRNA-34a conjugate, self-assembled in a single particle decorated with a polyethylene glycol corona for longevity, and a cell-penetrating peptide (TATp) for enhanced intracellular delivery. The MMP2-sensitivity of the system results in threefold higher cytotoxicity in MMP2-overexpressing HT1080 cells compared to low MMP2-expressing MCF7 cells. Cellular internalization of Dox increases by more than 70% after inclusion of TATp to the formulation. MMP2-sensitive MM also inhibits proliferation and migration of HT1080 cells. Moreover, GSH-sensitive MM allows for an efficient downregulation of Bcl2, survivin, and notch1 (65%, 55%, and 46%, respectively) in HT1080 cells. Combination of both conjugates in dual sensitive MM reduces HT1080 cell viability to 40% and expression of Bcl2 and survivin. Finally, 50% cell death is observed in 3D models of tumor mass. The results confirm the potential of the MM to codeliver miRNA-34a and doxorubicin triggered by dual stimuli inherent of tumor tissues.