Long noncoding RNA HIF1A-AS2 facilitates cell survival and migration by sponging miR-33b-5p to modulate SIRT6...

Long noncoding RNAs (lncRNAs) are emerging as vital regulators in various physiological and pathological processes. It was recently found that lncRNA HIF1A-AS2 could play oncogenic roles in several cancers. However, the function and regulatory mechanism of lncRNA HIF1A-AS2 in osteosarcoma (OS) remain largely unclear. In this study, we demonstrated that HIF1A-AS2 was overexpressed in OS tissues and cells. Downregulation of HIF1A-AS2 significantly affects multiple biological functions in OS cells, including cell proliferation, cell cycle progression, cell apoptosis, cell migration, and cell invasiveness. Mechanistic investigations demonstrated that HIF1A-AS2 can interact with miR-33b-5p and negatively regulate its expression, thereby upregulating the protein expression of miR-33b-5p's target SIRT6. Additionally, in vivo experiments using a xenograft tumor mouse model revealed that downregulation of HIF1A-AS2 suppresses tumor growth in OS. Taken together, a newly identified regulatory mechanism for the lncRNA HIF1A-AS2-miR-33b-5p-SIRT6 axis was systematically studied in OS, which could be a promising target for the treatment of OS.