Hsa_circ_0032463 acts as the tumor promoter in osteosarcoma by regulating the miR-330-3p/PNN axis

Osteosarcoma (OS), also known as bone cancer, is a threat to the lives of millions of adolescents worldwide. Although dedicated efforts have been invested in reducing the mortality rate of this bone cancer, the research community is yet to find the exact causes of OS. Thus, the present research aimed to study the association between circular RNA circ_0032463 and OS progression. The impact of circ_0032463 on cells with OS was first evaluated using reverse transcription-quantitative PCR. This evaluation was followed by the assessment of cell proliferation, viability, apoptosis, invasion and adhesion using BrdU, Cell Counting Kit-8, flow cytometry, Transwell and cell adhesion assays, respectively. RNA pull-down, RNA immunoprecipitation chip and dual-luciferase reporter systems were utilized to investigate the relationship between circ_0032463, microRNA (miR)-330-3p and Pinin desmosome associated protein (PNN) in OS. The findings indicated that circ_0032463 and PNN were highly expressed in OS tissues and OS cell lines, and that they facilitated cell proliferation, viability, invasion and adhesion, but attenuated cell apoptosis in OS cells. The low expression of miR-330-3p suppressed OS development. It was also noted that circ_0032463 inhibited miR-330-3p to upregulate PNN expression. In conclusion, this study confirmed that by regulating the miR-330-3p/PNN axis, circular RNA circ_0032463 could function as a tumor enhancer in cells with OS.