Recently, there is a hopefully tremendous interest in antisense therapeutics for clinical purposes. Single-stranded synthetic antisense oligonucleotides (As-ODNs) with monomers of chemically modified 18–21 deoxynucleotides complement the mRNA sequence in target gene. The target gene expression can be blocked because of created cleavage or disability of the mRNA by binding the As-ODNs to cognate mRNA sequences via sequence-specific hybridization. The idea of antisense therapy has become particular concerning that any sequence longer than a minimal number of nucleotides (17 for DNA and 13 for RNA) can be observed only once within the human genome. The mRNA is omnipresent more probably to manipulate compared to DNA, which results in multiple in vitro and in vivo applications for As-ODNs in the field of regulatory mechanisms of biological processes, cancer, viral infections and hereditary impairments. Although, there are uncertain clinical outcomes on the ability of this approach in treatment procedures despite achieving promising findings based on previous investigations. Accordingly, the efficacy, off-target effects, delivery are issues that should be investigated to obtain satisfactory results. In this review, we will explain the mechanism of action of As-ODNs and various types of modifications and their therapeutic purposes.

中文翻译：

---

反义寡核苷酸（AS-ODN）技术：原理、机制和挑战

最近，人们对用于临床目的的反义疗法产生了极大的兴趣。单链合成反义寡核苷酸 (As-ODNs) 与化学修饰的 18-21 个脱氧核苷酸单体互补目标基因中的 mRNA 序列。由于通过序列特异性杂交将 As-ODN 与同源 mRNA 序列结合，产生的 mRNA 切割或功能障碍，可以阻断靶基因表达。反义疗法的想法变得特别，因为任何长度超过最小核苷酸数（DNA 17 个，RNA 13 个）的序列在人类基因组中只能观察一次。与 DNA 相比，mRNA 无处不在，更可能被操纵，这导致 As-ODN 在生物过程调节机制领域的多种体外和体内应用，癌症、病毒感染和遗传性障碍。尽管根据先前的调查取得了有希望的发现，但这种方法在治疗程序中的能力的临床结果尚不确定。因此，功效、脱靶效应、递送是应该研究以获得满意结果的问题。在这篇综述中，我们将解释 As-ODN 的作用机制和各种类型的修饰及其治疗目的。