Key Laboratory of Medical Reprogramming Technology, Shenzhen Second People's Hospital, the First Affiliated Hospital of Shenzhen University, Shenzhen University School of Medicine, Shenzhen 518055, China.
CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
ACS Appl Mater Interfaces. 2021 Feb 24;13(7):7890-7896. doi: 10.1021/acsami.0c19217. Epub 2021 Jan 29.
Nanodrug delivery systems are very promising for highly efficient anticancer drug delivery. However, the present nanosystems are commonly located in the cytoplasm and mediate uncontrolled release of drugs into cytosol, while a large number of anticancer drugs function more efficiently inside the nucleus. Here, we constructed a CRISPR-dCas9-guided and telomerase-responsive nanosystem for nuclear targeting and smart release of anticancer drugs. CRISPR-dCas9 technology has been employed to achieve conjugation of mesoporous silica nanoparticles (MSNs) with a high payload of the active anticancer drug, doxorubicin (DOX). A specifically designed wrapping DNA was used as a telomerase-responsive biogate to encapsulate DOX within MSNs. The wrapping DNA is extended in the presence of telomerase, which is highly activated in tumor cells, but not in normal cells. The extended DNA sequence forms a rigid hairpin-like structure and diffuses away from the MSN surface. CRISPR-dCas9 specifically targets telomere-repetitive sequences at the tips of chromosomes, facilitating the precise delivery of the nanosystem to the nucleus, and effective drug release triggered by telomerase that was enriched around telomeric repeats. This study provides a strategy and nanosystem for nuclear-targeted delivery and tumor-specific release of anticancer drugs that will maximize the efficiency of cancer cell destruction.
纳米药物递送系统在高效抗癌药物递送方面具有很大的应用前景。然而，目前的纳米系统通常位于细胞质中，并介导药物不受控制地释放到细胞质中，而大量的抗癌药物在核内更有效地发挥作用。在这里，我们构建了一种基于 CRISPR-dCas9 引导和端粒酶响应的纳米系统，用于抗癌药物的核靶向和智能释放。CRISPR-dCas9 技术已被用于实现介孔硅纳米粒子（MSNs）与高载量的活性抗癌药物阿霉素（DOX）的结合。专门设计的包裹 DNA 被用作端粒酶响应的生物门控，将 DOX 封装在 MSNs 内。在端粒酶存在的情况下，包裹 DNA 被延伸，端粒酶在肿瘤细胞中高度激活，但在正常细胞中不激活。延伸的 DNA 序列形成刚性发夹状结构，并从 MSN 表面扩散开来。CRISPR-dCas9 特异性地靶向染色体末端的端粒重复序列，有助于纳米系统精确递送到细胞核，并通过富含端粒重复序列周围的端粒酶触发有效的药物释放。这项研究为抗癌药物的核靶向递送和肿瘤特异性释放提供了一种策略和纳米系统，将最大限度地提高癌细胞破坏的效率。
