Interleukin-4 receptor-targeted delivery of Bcl-xL siRNA sensitizes tumors to chemotherapy and inhibits tumor growth. (October 2017)

• Record Type: Journal Article
• Authors: Guruprasath, Padmanaban; Kim, Jihoon; Gunassekaran, Gowri Rangaswamy; Chi, Lianhua; Kim, Soyoun; Park, Rang-Woon; Kim, Sang-Hyun; Baek, Moon-Chang; Bae, Sang Mun; Kim, Sang-Yeob; Kim, Dong-Kyu; Park, In-Kyu; Kim, Won-Jong; Lee, Byungheon
• Is Part Of: Biomaterials. Volume 142(2017)
• Page Start: 101
• Page End: 111
• Publication Date: 2017-10
• Subjects: Bcl-xL -- BPEI-SPION -- Chemotherapy -- IL-4R -- siRNA; Biomedical materials -- Periodicals; Biocompatible Materials -- Periodicals; Biomatériaux -- Périodiques; 610.28
• DOI: 10.1016/j.biomaterials.2017.07.024
• Languages: English
• ISSNs: 0142-9612

Abstract

Abstract: IL-4 receptor (IL-4R) is commonly up-regulated on tumor cells, and interactions between the receptor and Interleukin-4 (IL-4) can induce the expression of anti-apoptotic proteins, including Bcl-xL. This contributes to tumor cell survival and their resistance to chemotherapy. In this study, we exploited IL-4R-targeted delivery of Bcl-xL siRNA to IL-4R-expressing tumor cells in order to sensitize them to chemotherapy. To target IL-4R, an IL-4R-binding peptide, IL4RPep-1, was attached to branched polyethyleneimine-superparamagnetic iron oxide nanoparticles (BPEI-SPION). These nanoparticles were then complexed with Bcl-xL-targeting siRNA. IL-4R-targeted BPEI-SPION/Bcl-xL siRNA more efficiently reduced Bcl-xL gene expression and enhanced cytotoxicity of doxorubicin in MDA-MB231 breast tumor cells compared to untargeted BPEI-SPION/Bcl-xL siRNA. The siRNA was released from the complexes after 15 h of incubation at pH 5.5 and was stable in the complexes up to 72 h in the serum. The IL-4R-targeted BPEI-SPION/siRNA was internalized by cells through IL-4R, successfully escaped the endosomes, and was dispersed into the cytoplasm. Near-infrared fluorescence and magnetic resonance imaging demonstrated that in vivo tumor homing and accumulation of IL-4R-targeted BPEI-SPION/siRNA were both higher than untargeted BPEI-SPION/siRNA. The IL-4R-targeted BPEI-SPION/Bcl-xL siRNA, in combination with doxorubicin, significantly inhibited tumor growth in mice compared to untargeted BPEI-SPION/Bcl-xL siRNA. These results suggest that the IL-4R-targeted delivery of Bcl-xL siRNA to IL-4R-expressing tumors can sensitize tumors to chemotherapy and enhance the efficacy of anti-tumor therapeutics. Graphical abstract: Interaction between IL-4 and IL-4R provides downstream signaling for the expression of Bcl-xL and inhibits doxorubicin-induced apoptosis. IL4RPep-1-labeled BPEI-SPION/Bcl-xL siRNA selectively binds to IL-4R-expressing tumor cells and is internalized into the cells through the receptor-mediated endocytosis, which contributes to the silencing of the Bcl-xL gene expression. This sensitizes IL-4R-expressing tumor cells to doxorubicin and enhances its therapeutic efficacy.