A theranostic micelleplex co-delivering SN-38 and VEGF siRNA for colorectal cancer therapy
Journal
Biomaterials
Journal Volume
86
Pages
92-105
Date Issued
2016
Author(s)
Lee, Shin-Yu
Yang, Chia-Ying
Peng, Cheng-Liang
Wei, Ming-Feng
Yao, Cheng-Jung
Abstract
The development of an efficient colorectal cancer therapy is currently a public health priority. In the present work, we proposed a multifunctional theranostic micellar drug delivery system utilizing cationic PDMA-block-poly(ε-caprolactone) (PDMA-b-PCL) micelles as nanocarriers of SN-38 (7-ethyl-10-hydroxycamptothecin), ultra-small superparamagnetic iron oxide nanoparticles (USPIO), and small interfering RNA (siRNA) that targets human vascular endothelial growth factor (VEGF). The VEGF siRNA was conjugated to polyethylene glycol (PEG) (siRNA-PEG) before complexation with the micelles in order to improve the siRNA's stability and to prolong its retention time in the blood circulation. To further improve the in vivo biosafety, we prepared mixed micelles using mPEG-PCL together with PDMA-b-PCL copolymer. The SN-38/USPIO-loaded siRNA-PEG mixed micelleplexes passively targeted to tumor regions and synergistically facilitated VEGF silencing and chemotherapy, thus efficiently suppressing tumor growth via a multi-dose therapy regimen. Additionally, the SN-38/USPIO-loaded siRNA-PEG mixed micelleplexes acted as a negative magnetic resonance imaging (MRI) contrast agent in T2-weighted imaging, resulting in a powerful tool for the diagnosis and for tracking of the therapeutic outcomes. In summary, we established a theranostic micellar drug and gene delivery system that not only synergistically combined gene silencing and chemotherapy but also served as a negative MRI contrast agent, which reveal its potential as a novel colorectal cancer therapy. © 2016 Elsevier Ltd.
Subjects
Colorectal cancer; Micelleplex; Micelles; MRI; SN-38; VEGF siRNA
SDGs
Publisher
Elsevier Ltd
Type
journal article
