Circular RNA hsa_circ_0001564 facilitates tumorigenesis of osteosarcoma via sponging miR-29c-3p

Abstract

Circular RNAs are a novel type of non-coding RNAs generated from back splicing, which has been verified to mediate multiple tumorigenesis. However, the role of circular RNA in osteosarcoma is still unclear. In this study, we preliminarily screened the circular RNAs expression profiles in osteosarcoma and investigated the potential regulation mechanism. The circular RNAs expression profiles in osteosarcoma were screened using circular RNA microarray analysis, and results showed that there were 1152 circular RNAs upregulated and 915 circular RNAs downregulated in tumor tissue compared to adjacent tissue. Hsa_circ_0001564, located at 5q35.3 and its associated gene symbol is CANX, was one of the significantly overexpressed circular RNAs in osteosarcoma tissue, as well as in osteosarcoma cell lines. In functional experiments, hsa_circ_001564 knockdown significantly suppressed the proliferation activity, induced cell-cycle arrest in G0/G1 phase, and promoted apoptosis in HOS and MG-63 cells. Subsequently, we explored the probable mechanism of hsa_circ_001564, and fortunately, bioinformatics analysis revealed that miR-29c-3p contained the complementary binding region with hsa_circ_0001564, which was confirmed by dual-luciferase reporter assay. Moreover, rescue experiments illustrated that miR-29c-3p could reverse the oncogenesis effect of hsa_circ_001564. Our study discovers that hsa_circ_0001564 acts as miR-29c-3p sponge to mediate the tumorigenicity, which could act as a potential biomarker for the osteosarcoma and provide a novel insight for competing endogenous RNA mechanism in osteosarcoma.