TSIX: A Novel Long Noncoding RNA in Cancer Development and Progression

Long noncoding RNAs (LncRNAs) represent a group of long noncoding RNA molecules exceeding 200 nt in length and lacking the capacity for protein coding. In recent years, the function and progress of lncRNA have attracted the attention of more and more researchers. Specifically, the long non-coding RNA, TSIX (TSIX transcript, XIST antisense RNA), plays a significant role in ensuring random X-chromosome inactivation. Recent investigations have highlighted the involvement of lncRNA TSIX in the development of various cancers, emphasizing its crucial functions in tumorigenesis. TSIX has emerged as a novel cancerassociated lncRNA and it is identified for its aberrant expression in diverse tumors, such as those of the breast, gastric, hepatocellular, head and neck, lung, esophageal squamous cell, and uterine smooth muscle. Furthermore, lncRNA TSIX regulates mRNA expression by binding to specific miRNAs, utilizing a competitive endogenous RNA regulatory mechanism. This interaction significantly influences tumor cell proliferation, migration, invasion, and apoptosis. LncRNA TSIX may serve as a useful biomarker or a prospective therapeutic target in a variety of malignant cancers because of the biological functions and mechanisms associated with it.