Circular RNAs: pivotal molecular regulators and novel diagnostic and prognostic biomarkers in non-small cell lung cancer

Purpose

Circular RNAs (circRNAs), a large class of non-coding RNAs with covalently closed-loop structures, are abundant, stable, conserved, and have tissue and developmental-stage specificities. The biological functions of circRNAs are varied. Moreover, circRNAs participate in various pathological processes, especially in multiple cancers. Lung cancer is the most frequent malignant tumor worldwide. Many studies have suggested that circRNAs are pivotal in non-small cell lung cancer. This article aims to provide a retrospective review of the latest research on the functions of circRNAs in non-small cell lung cancer. In particular, we focus our discussion on the role of circRNAs in cell-cycle regulation and the epithelial–mesenchymal transition, and also discuss the known regulatory molecular mechanisms of circRNAs in non-small cell lung cancer.

Methods

We reviewed the literature on circRNAs and non-small cell lung cancer from PubMed databases. Specifically, we focused on the roles and mechanisms of circRNAs in regulating the cell cycle and the epithelial–mesenchymal transition.

Results

Dysregulation of circRNAs is closely correlated with proliferation, migration, and invasion of non-small cell lung cancer, especially in terms of modulating cell-cycle regulation and the epithelial–mesenchymal transition.

Conclusion

Taken together, circRNAs have potential as biomarkers for the diagnosis, prognosis, and treatment of non-small cell lung cancer.