Circular RNA circ-PRMT5 facilitates non-small cell lung cancer proliferation through upregulating EZH2 via sponging miR-377/382/498.

Emerging evidence demonstrates that circular RNA (circRNA) is a novel class of non-coding RNA that plays a pivotal role in cancer. Recently, circ-PRMT5 was identified as an oncogene in bladder cancer. Nevertheless, its contribution to non-small cell lung cancer (NSCLC) is unknown. Herein, we aimed to clarify the biological role of circ-PRMT5 in NSCLC. High circ-PRMT5 expression was identified in NSCLC tissues and cell lines and positively correlated with larger tumor size, advanced clinic stage, lymph node metastasis as well as worse prognosis. Stable knockdown of circ-PRMT5 dramatically weakened the proliferative capacities of NSCLC cells both in vitro and in vivo. Mechanically, circ-PRMT5 could simultaneously effectively sponge three miRNAs (miR-377, miR-382 and miR-498) and alleviate their repression on the well-known oncogenic EZH2, resulting in increased EZH2 expression, thereby facilitating NSCLC progression. Importantly, a strong positive correlation between circ-PRMT5 and EZH2 expression was observed in NSCLC tissues. Overall, our data indicate that circ-PRMT5 is an oncogenic circRNA in NSCLC that can promote the growth of NSCLC via regulation of miR-377/382/498-EZH2 axis.