A novel circular RNA hsa_circ_0020123 exerts oncogenic properties through suppression of miR-144 in non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer-related death worldwide, while circulatory. Circular RNAs (circRNAs) are found to play important roles in cancer initiation and development. Herein, a novel functional circRNA hsa_circ_0020123 had been identified in NSCLC progression in this study, and elevated hsa_circ_0020123 expression could be observed in cancer tissues compared with that in matched normal lung tissues. Moreover, up-regulation of hsa_circ_0020123 was recognized to be closely associated with a poor differentiation degree, lymph node metastasis, a high TNM stage and dismal prognosis for NSCLC patients. Typically, knockdown of hsa_circ_0020123 could inhibit the NSCLC growth and metastasis both in vitro and in vivo, which could be reversed by the hsa_circ_0020123 overexpression. Importantly, miR-144 was identified as the hsa_circ_0020123-associated miRNA through performing RNA in vivo precipitation (RIP) in NSCLC cells using a biotin-labeled hsa_circ_0020123 probe. Besides, our results suggested that, miR-144 suppression had determined the oncogenic properties mediated by hsa_circ_0020123. In addition, hsa_circ_0020123 could upregulate ZEB1 and EZH2 through competitively binding with miR-144. Finally, the administration of hsa_circ_0020123 siRNA could suppress the growth and metastasis in NSCLC-bearing mice in vivo. In conclusion, the hsa_circ_0020123-miR-144-ZEB1/EZH2 axis is critical for NSCLC progression, which indicates that hsa_circ_0020123 is a potential target for NSCLC treatment.