Modified polyethyleneimine (PEI) has been widely used as siRNA delivery agents. Here, a new Triton X-100-modified low-molecular-weight PEI siRNA delivery agent is developed together with the coupling of 4-carboxyphenylboronic acid (PBA) and dopamine grafted vitamin E (VEDA). Triton X-100, a nonionic detergent, greatly improves the cellular uptake of siRNA as well as the siRNA escape from endosome/lysosome because of its high transmembrane ability. In addition, the boronate bond between PBA and VEDA of the transfection agent can be triggered to release its entrapped siRNA because of the high level of adenosine triphosphate (ATP) in cancer cells. The transfection agent is successfully applied to deliver siRNAs targeting endogenous genes of epidermal growth factor receptor (EGFR) and kinesin-5 (Eg5) to cancer cells, showing good results on Eg5 and EGFR silencing ability and inhibition of cancer cell migration. Further in vivo study indicates that the Triton X-100-modified transfection agent is also efficient to deliver siRNA to cancer cells and shows significant tumor growth inhibition on mice tumor models. These results indicate that the Triton X-100-modified ATP-responsive transfection agent is a promising gene delivery vector for target gene silencing in vitro and in vivo.
Antisense microRNA oligodeoxynucleotides (AMOs) are powerful tools to regulate microRNA functions. Unfortunately, severe off-target effects are sometimes observed. Due to the special topological and enzymatic properties of circular oligodeoxynucleotides (c-ODNs), we rationally designed and developed circular AMOs, which effectively inhibited microRNA functions with high target specificity and low off-target effects. Binding and enzymatic assays indicated that small circular AMOs could selectively bind to and further digest the target mature miR 21, which suggested that the topological properties of circular c-ODNs significantly decreased their off-target effects as microRNA inhibitors. Compared with their linear corresponding phosphorothioated AMOs, circular phosphorothioated AMOs could more effectively reduce the amount of carcinogenic miR 21 and miR 222 and upregulate the expression levels of downstream antitumor proteins of PTEN and PDCD4. In addition, c-PS-antimiRs induced much less nonspecific immunostimulatory effects compared with their linear partner PS-ODNs, further indicating the advantages of circular ODNs in nonspecific immunostimulation.
The temporal activation of siRNA provides a valuable strategy for the regulation of siRNA activity and conditional gene silencing. The bioorthogonal bond-cleavage reaction of benzonorbonadiene and tetrazine is a promising trigger in siRNA temporal activation. Here, we developed a new method for the bio-orthogonal chemical activation of siRNA based on the tetrazine-induced bond-cleavage reaction. Small-molecule activatable caged siRNAs were developed with the 5′-vitamin E-benzonobonadiene-modified antisense strand targeting the green fluorescent protein (GFP) gene and the mitotic kinesin-5 (Eg5) gene. The addition of tetrazine triggered the reaction with benzonobonadiene linker and induced the linker cleavage to release the active siRNA. Additionally, the conditional gene silencing of both exogenous GFP and endogenous Eg5 genes was successfully achieved with 5′-vitamin E-benzonobonadiene-caged siRNAs, which provides a new uncaging strategy with small molecules.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.