Circ_0072088 Promotes Proliferation, Migration, and Invasion of Esophageal Squamous Cell Cancer by Absorbing miR-377

Circular RNA (circRNA) is an endogenous noncoding RNA. Accumulative investigations have confirmed that circRNAs play a vital role in carcinogenesis and tumor progression. Herein, we examined the expression and mechanism of circ_0072088 in esophageal squamous cell carcinoma (ESCC). As a result, circ_0072088 was significantly overexpressed in ESCC tissues and cells, which was closely associated with tumor size, invasion depth, clinical stage, and lymph node metastasis of esophageal cancer. Nuclear and cytoplasmic separation as well as FISH assays showed that circ_0072088 was mainly localized in the cytoplasm of ESCC cells. RNase R treatment assay revealed that circ_0072088 was steadier than linear ZFR mRNA. circ_0072088 promoted ESCC cell proliferation, migration and invasion in vitro, and cell proliferation in vivo. Mechanistically, circ_0072088 upregulated VEGF gene expression by acting as the sponge of miRNA-377. In conclusion, circ_0072088 might be used as a diagnostic biomarker and therapeutic target for ESCC.