Synchronous conjugation of i-motif DNA and therapeutic siRNA on the vertexes of tetrahedral DNA nanocages for efficient gene silence

• Published in: Acta pharmaceutica Sinica. B Vol. 11; no. 10; pp. 3286 - 3296
• Main Authors: Han, Xiu, Xu, Xiang, Wu, Ziheng, Wu, Zhenghong, Qi, Xiaole
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2021; Elsevier
• Subjects: Biocompatibility; Cancer; DNA tetrahedron; Endosomal escape; Gene delivery; Gene silence; i-motif; Original; siRNA; Gene delivery; i-motif; Gene silence; DNA tetrahedron; Biocompatibility; siRNA; Endosomal escape; Cancer
• ISSN: 2211-3835; 2211-3843
• DOI: 10.1016/j.apsb.2021.02.009

The functionality of DNA biomacromolecules has been widely excavated, as therapeutic drugs, carriers, and functionalized modification derivatives. In this study, we developed a series of DNA tetrahedron nanocages (Td), via synchronous conjugating different numbers of i-(X) and therapeutic siRNA on four vertexes of tetrahedral DNA nanocage (aX-Td@bsiRNA, a+b = 4). This i-motif-conjugated Td exhibited good endosomal escape behaviours in A549 tumor cells, and the escape efficiency was affected by the number of i-motif. Furthermore, the downregulating mRNA and protein expression level of epidermal growth factor receptor (EGFR) caused by this siRNA embedded Td were verified in A549 cells. The tumor growth inhibition efficiency of the 2X-Td@2siRNA treated group in tumor-bearing mice was significantly higher than that of non-i-motif-conjugated Td@2siRNA (3.14-fold) and free siRNA (3.63-fold). These results demonstrate a general strategy for endowing DNA nanostructures with endosomal escape behaviours to achieve effective in vivo gene delivery and therapy. siRNA-loaded DNA tetrahedron nanocages escape from the endosomal degradation and successfully interfere in gene and protein expression level of EGFR in tumor cells. [Display omitted]