ABSTRACT
Circular RNA (circRNA) is considered to be non-coding RNA due to the deletion of the 5' cap structure and lacks the function of encoding proteins or polypeptides. With the development of high-throughput transcriptome sequencing, ribosome sequencing and other technologies, researchers have discovered that there were short open reading frames (sORF) and internal ribosome entry sites (IRES) in the sequence of some circRNAs which can encode polypeptides or protein and play important roles in the proliferation of malignant tumors such as glioma, hepatoma, gastric cancer, breast cancer, and colon cancer. This paper reviews the coding function of circRNA and analyzes the role of its encoded production-polypeptides or protein in the proliferation mechanism of human malignant tumors.