Electrostatic Attractive Self‐Delivery of siRNA and Light‐Induced Self‐Escape for Synergistic Gene Therapy

Abstract

Small interfering RNA (siRNA) holds immense promise for suppressing gene expression and treating various life‐threatening diseases, including cancer. However, efficient delivery and lysosomal escape remain critical challenges that hinder the therapeutic effectiveness of siRNA. Herein, cationic photosensitizer (NB‐Br) is grafted onto polo‐like kinase 1 (PLK1) siRNA to form an amphiphilic siRNA‐photosensitizer conjugate (siPLK1‐NB), which can self‐assemble into nanoparticles (siPLK1‐NB NPs) via electrostatic attraction. Notably, siPLK1‐NB NPs exhibit rapid and efficient cell endocytosis, as well as outstanding tumor‐targeting property in multiple tumor‐bearing mice models. When siPLK1‐NB NPs are located inside tumor cell lysosomes, the generated reactive oxygen species (ROS) after photoactivation can disrupt the lysosome membrane structure and facilitate siRNA escape from lysosomes. Under light irradiation, siPLK1‐NB NPs can downregulate PLK1 expression and induce photodynamic killing, effectively inhibiting tumor cell growth both in vitro and in vivo. Consequently, this study provides a novel design strategy for carrier‐free siRNA delivery systems. As far as it is known, this is the first report of a carrier‐free siRNA delivery system based on electrostatic attraction.

Chemically Modified Platforms for Better RNA Therapeutics

“…An innovative amphiphilic siRNA-photosensitizer conjugate, dubbed siPLK1-NB, was engineered by covalently linking a cationic photosensitizer (NB-Br) with polo-like kinase 1 (PLK1) siRNA (Figure 21c). 315 This novel construct spontaneously self-assembled into nanoparticles (siPLK1-NB NPs) through electrostatic interactions. These nanoparticles demonstrated rapid cellular endocytosis, impressive tumortargeting specificity across various murine tumor models, and potent lysosomal escape catalyzed by ROS generation upon photoactivation.…”

“…(c) Scheme showing the preparation of the siRNA-NB conjugate, and the self-assembly of siRNA-NB NPs. Reproduced with permission from ref . Copyright 2023 Wiley.…”

“…In a parallel investigation, researchers addressed the intricate issues surrounding efficient cellular uptake and lysosomal evasion in siRNA therapy. An innovative amphiphilic siRNA-photosensitizer conjugate, dubbed siPLK1-NB, was engineered by covalently linking a cationic photosensitizer (NB-Br) with polo-like kinase 1 (PLK1) siRNA (Figure c) . This novel construct spontaneously self-assembled into nanoparticles (siPLK1-NB NPs) through electrostatic interactions.…”

A quaternary ammonium-based nanosystem enables delivery of CRISPR/Cas9 for cancer therapy

“…26 PLK1 plays a critical role in carcinogenesis, and the inhibition of its expression can induce apoptosis of tumor cells and lead to G 2 /M phase cell cycle arrest. 27,28 Therefore, downregulating its expression level has been considered a promising approach in cancer treatment, e.g., using siRNA to knockdown the expression [29][30][31] and the CRISPR/Cas9 technique to achieve its knockout. 32,33 In this study, a CRISPR/ Cas9 delivery system was developed for the delivery of Cas9/ PLK1 sgRNA RNP complexes (denoted as RNP PLK1 ) to improve genome editing efficiency (Scheme 1).…”

Bioorthogonal Activation of RCA-Based Amplifiable DNAzymes in Bimetallic NMOF for Precise Gene/Chemo-Dynamic Combination Therapy

“…In the era of precision cancer therapy, precise initiation and efficient treatment are crucial issues to ensure satisfactory efficacy, which remains challenging in biomedicine. , Gene therapy, which can modulate disease-related proteins to continuously inhibit tumor proliferation and metastasis at the root, is considered the ultimate panacea for cancer treatment. , Among various gene drugs such as antisense oligonucleotides (ASOs), small interfering RNA (siRNA), , and clustered regularly interspersed short palindromic repeats (CRISPRs), , etc. , DNAzyme has received special attention owing to its flexible design and enzyme-like activity, which enables it to specifically recognize and continuously cleave target genes. − However, the current DNAzyme-based gene therapy faces several limitations: (a) low transfection efficiency and insufficient cofactor supply, , (b) poor specificity causing adverse reactions, , and (c) inadequate effects of monotherapy. − …”