CircCOCH plays a critical role in Hepatocellular carcinoma through modulating miR-450a and activating PI3K/mTOR pathway

Hepatocellular carcinoma (HCC) is a primary liver cancer with high pathogenicity and extremely poor prognosis. The role of circular RNAs (circRNAs) in HCC carcinogenesis and progression remains to be determined. Based on the analysis of HCC-related databases, as well as the expression analysis and identification of 25 HCC patient tissues and HCC cell lines, we found that the hsa_circ_0031431 (circCOCH) is significantly highly expressed in HCC tissues and cell lines. High circCOCH expression is associated with enhanced tumor proliferation and metastasis, and knocking down circCOCH can inhibit the growth of HCC in vivo and in vitro. Mechanistic studies show that circCOCH upregulates the expression of epidermal growth factor receptor (EGFR) through sponge miR-450a, thereby activating the Phosphoinositide 3-kinases (PI3Ks) cell pathway to promote HCC proliferation and metastasis. Futhermore, we found that IGF2BP3 mediates the biogenesis of circCOCH. The present study provides innovative insights into the role of circRNAs in the etiology of HCC carcinogenesis and might serve as a new promising therapeutic target for HCC.