Hsa_circ_0001687 Function as a ceRNA to Facilitate Hepatocellular Carcinoma Progression via miR-140- 3p/FOXQ1 Axis

Background: Increasingly convincing evidence has revealed that circular RNAs (circRNAs) are critical regulatory components of hepatocellular carcinoma (HCC) genesis. However, the expression of circRNAs in HCC and the relevance of circRNAs to HCC progression remain largely unexplained. Methods: qRT-PCR or western blotting was utilized to confirm circ_0001687, miR-140-3p, and Forkhead Box q1 (FOXQ1) levels in HCC tissues or cells. Cell proliferation ability was evaluated via CCK-8 and colony formation assay. The correlation of circ_0001687 or FOXQ1 and miR-140- 3p was determined using dual luciferase reporter assay. Nude mice xenograft tumor model was constructed to verify the effect of circ_0001687 on tumor growth. Results: Circ_0001687 was elevated in HCC. Function assays and the nude mice xenograft tumor model indicated that circ_0001687 acts as a promoting gene in HCC to regulate the proliferation of the tumor cell and foster tumor growth. Further mechanistic exploration revealed that the tumor growth-promoting mechanism of circ_0001687 relied on blocking the inhibitory effect of miR-140- 3p on FOXQ1 and activating FOXQ1 expression. Conclusion: This research indicated the role of circ_0001687/miR-140-3p/FOXQ1 network in regulating HCC development. These may provide new insights into the treatment of HCC.