Translation regulatory long non‐coding RNA 1 negatively regulates cell radiosensitivity via the miR‐22‐3p/SP1 axis in non‐small cell lung cancer

Abstract Objective Non‐small cell lung cancer (NSCLC) occupies 85% of lung cancer. Long non‐coding RNAs (LncRNAs) can regulate the radiosensitivity of cancers. This study explored the mechanism of lncRNA TRERNA1 in the radiosensitivity of NSCLC cells. Methods LncRNA TRERNA1 level in NSCLC cell lines was determined. NSCLC cell radiation tolerance was measured. TRERNA1 expression was silenced or overexpressed in A549/HCC827 cells with the highest/lowest radiation tolerance, respectively. The contents of γ‐H2AX and SA‐β‐gal in NSCLC cells after radiation induction were detected. The targeted binding of TRERNA1 to miR‐22‐3p and miR‐22‐3p to SP1 were verified by dual‐luciferase assay. SP1 expression were detected. Functional rescue experiments were implemented to confirm the roles of miR‐22‐3p and SP1 in the regulatory mechanism of TRERNA1. Results TRERNA1 was upregulated in NSCLC cells. TRERNA1 silencing enhanced radiosensitivity of NSCLC cells. TRERNA1 silencing elevated the contents of γ‐H2AX and SA‐β‐gal in A549 cells after radiation induction, while TRERNA1 overexpression showed an opposite trend in HCC827 cells. There were targeting relationships between TRERNA1 and miR‐22‐3p, and miR‐22‐3p and SP1. miR‐22‐3p repression or SP1 overexpression abolished the effects of TRERNA1 silencing. Conclusion TRERNA1 silencing enhanced radiosensitivity of NSCLC cells via the miR‐22‐3p/SP1 axis. This study may offer new targets for NSCLC treatment.