hsa_ circ_0051428 Facilitates the Progression of Thyroid Cancer by Sponging miR-1248 to Up-Regulate FN1

Evidence displays that circular RNAs (circRNAs) are considerable mediators of numerous processes in cancer development. Given that many circRNAs are not functionally characterized, our aim was to explore the function and mechanisms of circ_0051428 in thyroid cancer (TC). The analysis of circ_0051428, miR-1248 and FN1 mRNA expression was conducted using real-time quantitative polymerase chain reaction. Cell growth was observed using CCK-8 and colony formation assays. Cell migration was investigated using wound healing assay. Cell apoptosis was identified by the expression of apoptosis-related proteins (Bax and Bcl-2) using Western blotting. Animal models were established to testify the role of circ_0051428 in vivo. The assumed binding between miR-1248 and circ_0051428 or FN1 was identified using dual-luciferase reporter or RIP assay. circ_0051428 exhibits an abnormally elevated expression in TC. circ_0051428 deficiency caused inhibition of TC cell proliferation, migration, clonogenic capacity, and inhibition of tumor growth in vivo. circ_0051428 directly targeted miR-1248, and FN1 was a target downstream of circ_0051428/miR-1248 axis. circ_0051428 could sponge miR-1248 to upregulate FN1. Furthermore, miR-1248 downregulation recovered circ_0051428 deficiency-suppressed cancer cell proliferation, survival and migration. Besides, the repressive effects of FN1 knockdown on cancer cell growth, survival and migration were also partly abolished by miR-1248 downregulation. circ_0051428 targeted miR-1248 to modulate FN1 expression, thereby facilitating the malignant progression of TC, which contributed to the understanding of the molecular mechanism of TC development.