Circular RNA circ_0073181 contributes to tumorigenesis by regulating protein tyrosine phosphatase receptor type E via miR-548p in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a major world public problem in the world, with high morbidity and mortality rates. Circular RNA (circRNA) circ_0073181 has been reported to be related to HCC development. However, the mechanism of circ_0073181 in HCC is far from being addressed. Circ_0073181, microRNA-548p (miR-548p) and protein tyrosine phosphatase receptor type E (PTPRE) level were detected by real-time quantitative PCR (RT-qPCR). Cell proliferation, migration, invasion and apoptosis were detected by Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine, wound healing, transwell and flow cytometry assay. Protein levels of proliferating cell nuclear antigen, Bcl-2 related X protein (Bax) and PTPRE were examined by western blot assay. The binding relationship between miR-548p and circ_0073181 or PTPRE was predicted by circular RNA interactome and targetScan and then verified by a dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The biologic role of circ_0073181 on HCC tumor growth was examined by the xenograft tumor model in vivo. Circ_0073181 and PTPRE were upregulated, and miR-548p was decreased in HCC tissues and cells. Furthermore, circ_0073181 knockdown could boost proliferation, migration, invasion and repress apoptosis of HCC cells in vitro. The mechanical analysis suggested that circ_0073181 could regulate PTPRE expression by sponging miR-548p. In addition, circ_0073181 knockdown suppressed cell growth of HCC in vivo. Circ_0073181 silencing could inhibit HCC cell growth and metastasis partly by regulating the miR-548p/ PTPRE axis, providing a promising therapeutic target for the HCC treatment.