Silencing of the Long Non-Coding RNA TTN-AS1 Attenuates the Malignant Progression of Osteosarcoma Cells by Regulating the miR-16-1-3p/TFAP4 Axis

Xianghai Meng; Zhenjun Zhang; Lin Chen; Xi Wang; Qingguo Zhang; Shuheng Liu

doi:10.3389/fonc.2021.652835

Silencing of the Long Non-Coding RNA TTN-AS1 Attenuates the Malignant Progression of Osteosarcoma Cells by Regulating the miR-16-1-3p/TFAP4 Axis

Front Oncol. 2021 Jun 1:11:652835. doi: 10.3389/fonc.2021.652835. eCollection 2021.

Authors

Xianghai Meng¹, Zhenjun Zhang¹, Lin Chen², Xi Wang³, Qingguo Zhang³, Shuheng Liu³

Affiliations

¹ Trauma Center, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.
² Department of Burn Reconstructive Surgery, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.
³ Department of Spine Surgery, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.

Abstract

Objectives: Osteosarcoma (OS) is a type of bone malignancy. This study attempted to explore the effect of long non-coding RNA TTN-AS1 (TTN-AS1) on OS and to determine its molecular mechanisms.

Methods: The expression of TTN-AS1, microRNA-16-1-3p (miR-16-1-3p), and transcription factor activating enhancer binding protein 4 (TFAP4) in OS was assessed using qRT-PCR. The OS cell proliferation, migration, and invasion were measured using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), wound-healing, and transwell assays. N-cadherin and MMP-2 protein level was determined with western blot. Interactions between TTN-AS1 and miR-16-1-3p or TFAP4 and miR-16-1-3p were confirmed using the dual-luciferase reporter assay. Additionally, an OS xenograft tumor model was constructed to assess the effect of TTN-AS1 on tumor growth.

Results: TTN-AS1 and TFAP4 expression was increased in OS, while miR-16-1-3p expression was decreased. TTN-AS1 silencing restrained OS cell proliferation, migration, invasion, N-cadherin and MMP-2 protein expression, and hindered tumor growth. MiR-16-1-3p overexpression retarded the malignant behavior of OS cells. TTN-AS1 played a carcinostatic role by down-regulating miR-16-1-3p in the OS cells. Moreover, miR-16-1-3p inhibition or TFAP4 elevation weakened the suppressive effect of TTN-AS1 silencing on OS cell tumor progression.

Conclusion: TTN-AS1 promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of OS cells via mediating the miR-16-1-3p/TFAP4 axis. TTN-AS1 may be a critical target for improving OS.

Keywords: long non-coding RNA TTN-AS1; microRNA-16-1-3p; osteosarcoma; proliferation; transcription factor activating enhancer binding protein 4.