Upregulation of FTX Promotes Osteosarcoma Tumorigenesis by Increasing SOX4 Expression via miR-214-5p

Long-chain non-coding RNA (LncRNA) plays a key role in the biological processes of tumors. LncRNA-FTX has been the invasion of tumors. However, its function and mechanism in osteosarcoma have not been studied.

qRT-PCR was measured the expression levels of FTX and miR-214-5p in osteosarcoma. The protein levels of SRY-related HMG box transcription factor 4 (SOX4) were detected by Western Blot. Cholecystokinin (CCK-8) assay, cell colony formation and Transwell assay, Annexin V-FITC/PI assay were analyzed the effects of FTX and miR-214-5p on cell proliferation, cell invasion and apoptosis. The relationship between FTX, miR-214-5p and SOX4 was analyzed by bioinformatics analysis and Luciferase. The tumor changes in mice were detected by vivo experiments in nude mice.

The expression levels of FTX were increased in osteosarcoma tissues and cell lines and negatively correlated with the expression levels of miR-214-5p. FTX could modulate the expression of miR-214-5p in osteosarcoma cell lines. sh-FTX inhibited the growth and metastasis of osteosarcoma. FTX could regulate the growth of osteosarcoma through miR-214-5p. The knockdown of miR-214-5p reversed the inhibitory effect of sh-FTX on osteosarcoma cell proliferation and growth in mice. Furthermore, FTX regulated the expression of SOX4 by acting as a sponge of miR-214-5p in osteosarcoma.

FTX could promote proliferation, invasion and inhibited apoptosis by regulating miR-214-5p/SOX4 axis in osteosarcoma, suggesting that FTX might be a potential target for osteosarcoma treatment.