Circular RNA 0000311 Aggravates the Aggressiveness of Oral Squamous Cell Carcinoma via miR-876-5p/EZH2 Axis.

The purpose of the present study was to investigate the potentials of circ_0000311 in oral squamous cell carcinoma (OSCC). Quantitative real-time polymerase chain reaction (qRT-PCR) was applied for calculating the mRNA and miRNA level. Western blot was performed to determine protein expression. The binding sites between miR-876-5p and circ_0000311/Enhancer of zeste homolog-2 (EZH2) were predicted using bioinformatics tools and confirmed by luciferase and RNA pull-down assays. Cell proliferation was detected using CCK-8 and colony formation assay. Cell migration and invasion were detected using transwelll assay. Cellular functions were determined using CCK-8, colony, and transwell assay. The results showed that circ_0000311 was overexpressed in OSCC tissues and cells. However, circ_0000311 knockdown impeded the proliferation and epithelial-mesenchymal transition (EMT) of OSCC cells. Circ_0000311 targeted miR-876-5p, down-regulation of which promoted the aggressiveness of OSCC. Additionally, circ_0000311 sponged miR-876-5p to up-regulate a key regulator of EMT EZH2, which promoted the proliferation and aggressiveness of OSCC. Taken together, circ_0000311 aggravated the OSCC progression via regulating miR-876-5p/EZH2 axis.