Long non-coding RNA TTN antisense RNA 1 facilitates hepatocellular carcinoma progression via regulating miR-139-5p/SPOCK1 axis

ABSTRACT

Reportedly, long non-coding RNAs (lncRNAs) are implicated in hepatocellular carcinoma (HCC) progression, yet little is known concerning the biological functions of TTN antisense RNA 1 (TTN-AS1) in HCC. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) was performed for detecting TTN-AS1, SPOCK1 mRNA, and miR-139-5p expressions in HCC cells and tissues. After TTN-AS1 was overexpressed or knocked down in HCC cells, CCK-8 and 5-Ethynyl-2ʹ-deoxyuridine (EdU) assays were carried out for examining cell multiplication. Transwell assays were conducted for evaluating HCC cell migration and invasion. Dual-luciferase reporter assay was employed for verifying the binding relationships between miR-139-5p and TTN-AS1, and between SPOCK1 3ʹUTR and miR-139-5p. Western blot was employed to measure SPOCK1, E-cadherin, N-cadherin, and Vimentin protein expressions. We demonstrated that, TTN-AS1 and SPOCK1 expression levels were remarkably enhanced in HCC cells and tissues, whereas miR-139-5p expression was observably reduced. Functional experiments suggested that TTN-AS1 knockdown markedly repressed HCC cell multiplication, migration, epithelial-mesenchymal transition (EMT), and invasion. In addition, TTN-AS1 interacted with miR-139-5p and decreased its expression. Moreover, SPOCK1 was a miR-139-5p target, and miR-139-5p inhibitors were able to reverse TTN-AS1 knockdown-induced inhibitory effect on SPOCK1 expression. SPOCK1 overexpression plasmid could counteract TTN-AS1 knockdown-induced inhibiting impact on HCC cell multiplication, migration, invasion, and EMT. In conclusion, TTN-AS1 expression level is remarkably enhanced in HCC, and TTN-AS1 can promote the multiplication, migration, invasion, and EMT of HCC cells via regulating miR-139-5p/SPOCK1 axis.

KEYWORDS:

• TTN-AS1
• hepatocellular carcinoma (HCC)
• MiR-139-5p
• SPOCK1
• EMT

Highlights

• TTN-AS1 expression was notably elevated in HCC cell lines and tissues

• TTN-AS1 knockdown suppressed HCC cell multiplication, migration, and invasion

TTN-AS1 regulated SPOCK1 expression by sponging miR-139-5p

Acknowledgements

We thank Hubei Yican Health Industry Co., Ltd for its linguistic assistance during the preparation of this manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study is supported by Tibetan Medicine Regional Cooperative Innovation Center Item [2018XTCX006].