Bioinformatics screening and clinical validation of CircRNA and related miRNA in male osteoporosis.

BACKGROUND: The pathogenesis of male osteoporosis (MOP) remains unclear, with the role of genetic factors attracting the attention of researchers. In the present study, we aimed to investigate critical circRNA biomarkers associated with male osteoporosis. METHODS: RNA-sequencing was performed to investigate the circRNA expression profiles between 3 men with osteoporosis and 3 with normal mass density. Then, shared mRNAs between host genes acquired in this present study and mRNAs acquired in previous study were identified to screen vital circRNAs associated with male osteoporosis. PPI networks of shared mRNAs were constructed and the hub genes in the PPI networks were identified with CytoHubba, a plugin in Cytoscape software (3.10.1). Finally, a ceRNA network of four circRNAs derived from three hub genes was constructed. Validation experiments were performed on selected circRNAs and related miRNAs in this ceRNA network using peripheral blood clinical samples. RESULTS: In total, 657 circRNAs were detected in male osteoporosis. The shared mRNAs were significantly enriched in the metabolic pathways, RNA transport, Ubiquitin mediated proteolysis and Amyotrophic lateral sclerosis. Then, three genes, including SETD2, ATM and XPO1, were identified as hub genes with four algorithms. Ultimately, the ceRNA network, involving 4 circRNAs, 40 miRNAs, and 592 mRNAs, was obtained. Using 35 clinical samples, three potential circRNAs and three miRNAs associated with male osteoporosis were selected for validation. It was ultimately found that three miRNAs were upregulated in MOP, while hsa-circ-9130, novel_circ_0014940 and hsa-circ-0054894 were upregulated, hsa-circ-2484 and novel_circ_0033084 were downregulated in patients with MOP. CONCLUSION: We emphasized the roles of several significantly up- and down-regulated circRNAs and four circRNAs derived from three hub genes in male osteoporosis. Differences in expression were confirmed for three miRNAs and five circRNAs in the ceRNA network among patients with male osteoporosis.