State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Functional Polymer Materials of Ministry of Education, College of Chemistry, Nankai University, Tianjin, 300071, China.
Tianjin Neurological Institute, Key Laboratory of Post-Neurotrauma Neuro-Repair and Regeneration in Central Nervous System, Ministry of Education and Tianjin City, Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300052, China.
Adv Mater. 2019 Dec;31(51):e1905751. doi: 10.1002/adma.201905751. Epub 2019 Nov 11.
The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated (Cas) enzyme, Cas13a, holds great promise in cancer treatment due to its potential for selective destruction of tumor cells via collateral effects after target recognition. However, these collateral effects do not specifically target tumor cells and may cause safety issues when administered systemically. Herein, a dual-locking nanoparticle (DLNP) that can restrict CRISPR/Cas13a activation to tumor tissues is described. DLNP has a core-shell structure, in which the CRISPR/Cas13a system (plasmid DNA, pDNA) is encapsulated inside the core with a dual-responsive polymer layer. This polymer layer endows the DLNP with enhanced stability during blood circulation or in normal tissues and facilitates cellular internalization of the CRISPR/Cas13a system and activation of gene editing upon entry into tumor tissue. After carefully screening and optimizing the CRISPR RNA (crRNA) sequence that targets programmed death-ligand 1 (PD-L1), DLNP demonstrates the effective activation of T-cell-mediated antitumor immunity and the reshaping of immunosuppressive tumor microenvironment (TME) in B16F10-bearing mice, resulting in significantly enhanced antitumor effect and improved survival rate. Further development by replacing the specific crRNA of target genes can potentially make DLNP a universal platform for the rapid development of safe and efficient cancer immunotherapies.
成簇规律间隔短回文重复序列（CRISPR）/CRISPR 相关（Cas）酶 Cas13a 具有通过靶向识别后产生的旁效应选择性破坏肿瘤细胞的潜力，有望用于癌症治疗。然而，这些旁效应并非专门针对肿瘤细胞，并且在全身给药时可能会引起安全性问题。本文描述了一种可以将 CRISPR/Cas13a 激活限制在肿瘤组织中的双锁定纳米颗粒（DLNP）。DLNP 具有核壳结构，其中 CRISPR/Cas13a 系统（质粒 DNA，pDNA）被包裹在核心内，具有双响应聚合物层。该聚合物层赋予 DLNP 在血液循环或正常组织中增强的稳定性，并促进 CRISPR/Cas13a 系统的细胞内化和进入肿瘤组织后的基因编辑激活。在仔细筛选和优化靶向程序性死亡配体 1（PD-L1）的 CRISPR RNA（crRNA）序列后，DLNP 证明了在 B16F10 荷瘤小鼠中有效激活 T 细胞介导的抗肿瘤免疫和重塑免疫抑制肿瘤微环境（TME），从而显著增强抗肿瘤效果和提高生存率。通过替换靶基因的特定 crRNA 进行进一步开发，DLNP 可能成为快速开发安全有效的癌症免疫疗法的通用平台。
