TMPO-AS1 Regulates the Aggressiveness-Associated Traits of Nasopharyngeal Carcinoma Cells Through Sponging miR-320a.

Background: Previous evidence demonstrates that the long non-coding RNA (lncRNA) TMPO antisense RNA 1 (TMPO-AS1) is involved in the aggressiveness of several cancers. Nevertheless, its functions in nasopharyngeal carcinoma (NPC) are unclear.

Methods: qRT-PCR was used to evaluate the levels of TMPO-AS1 and miR-320a in NPC tissues. Furthermore, the growth and invasiveness of NPC cells were evaluated by colony formation and Transwell assays. The protein expression ofSRY-Box Transcription Factor 4 (SOX4) was observed by Western blotting and immunohistochemistry. Bioinformatic prediction and luciferase reporter assays were used to explore the interaction between miR-320a and TMPO-AS1. The transplanted model was employed to disclose the interference of TMPO-AS1 in the tumor growth of NPC cells in vivo.

Results: We found that TMPO-AS1 was distinctly upregulated in NPC. Downregulation of TMPO-AS1 restrained aggressiveness-associated traits in NPC cells. Nevertheless, upregulation of TMPO-AS1 yielded the opposite results. Further studies revealed that lncRNA TMPO-AS1 acts as a "sponge" for miR-320a, resulting in increased levels of SOX4 in NPC cells. Finally, TMPO-AS1 silencing suppressed tumor growth of NPC cells in vivo.

Conclusion: Collectively, these results reveal the presence of a novel TMPO-AS1/miR-320a/SOX4 pathway associated with NPC progression, suggesting that lncRNA TMPO-AS1 may be a potential therapeutic target for NPC.