CircRNA_104916 regulates migration, apoptosis and epithelial-mesenchymal transition in colon cancer cells.

Circular RNAs (circRNAs) are a class of noncoding RNAs that are differentially expressed in tissues with a great potential in regulating the tumorigenesis and metastasis. The COX proportional hazard model predicts that among these, the relative expression of circRNA_104916 and lymphatic metastatic status independently predict the prognosis of patients with cancer. In the present study, we show that circRNA_104916 is downregulated in colorectal cancers as compared to the adjacent normal tissues. The expression of circRNA_104916 is negatively correlated with the tumor size, T stage and lymphatic metastasis. Patients with higher relative circRNA_104916 expression have a better post-operative disease-free survival as compared with those with lower relative expression. Forced expression of circRNA_104916 induces cell apoptosis and G2/M phase arrest by activating apoptosis pathway and cyclin proteins, thereby inhibiting proliferation of colon cancer cell lines, including LoVo and Caco-2. Additionally, overexpression of circRNA_104916 significantly suppresses migration and invasion of tumor cells by inhibiting the epithelial-mesenchymal transition. In conclusion, this study reveals that circRNA_104916 is a potential biomarker and therapeutic target for colorectal cancers.