G-quadruplex (G4) is an important type of nucleic acid secondary structure. An abundance of potential G4-forming sites have been shown to exist in genomes, leading to increasing interest in this research field. G4 motifs are thought to be involved in the regulation of diverse biological processes and to interact with various protein factors. Because of their important regulatory functions, G4s could have a variety of applications, the most meaningful of which is the role of G4s as potential targets of antitumor therapies. Here, we focus on the regulatory functions of G4s in tumor-related gene regulation and the use of G4s in the design of antitumor therapies, including relatively recently reported G4-related binding proteins, regulatory mechanisms, and G4-ligand designs. We also introduce G4 probes for the identification of G4 structure formation in live cells. Finally, we describe some challenges in this field and the new G4-related research field.

G-四链体（G4）是一种重要的核酸二级结构。已显示基因组中存在大量潜在的G4形成位点，从而引起对该研究领域的日益增长的兴趣。G4基序被认为参与多种生物过程的调节并与各种蛋白质因子相互作用。由于其重要的调节功能，G4s可能有多种应用，其中最有意义的是G4s作为抗肿瘤治疗潜在靶点的作用。在这里，我们专注于G4s在肿瘤相关基因调控中的调控功能，以及G4s在抗肿瘤疗法设计中的用途，包括最近报道的G4相关结合蛋白，调控机制和G4配体设计。我们还介绍了用于鉴定活细胞中G4结构形成的G4探针。最后，我们描述了该领域以及与G4相关的新研究领域中的一些挑战。