Circular RNAs: The star molecules in cancer.

Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs with a closed loop structure. These RNAs are produced by pre-mRNA through variable shear processing and are highly conserved. Such highly conserved molecules play an important role in biology, especially in cancer biology. With the development of experimental techniques such as circRNA microarray screening and high-throughput sequencing technologies, the mystery of circRNAs has gradually been unveiled and the values of function and application have gradually emerged. Among them, cancer-related circRNAs are the most eye-catching. Numerous studies have shown that some circRNAs were involved in the pathogenesis of cancer. This review systematically introduced the cancer-related circRNAs and their origin, formation mechanisms, functions, and applications in the diagnosis and treatment of sixteen kinds of tumors.