LncRNA TATDN1 contributes to the cisplatin resistance of non-small cell lung cancer through TATDN1/miR-451/TRIM66 axis

Abstract

ABSTRACT Background Chemoresistance has been considered to be a major obstacle for cancer therapy clinically. Long non-coding RNAs (LncRNAs) are asscociated with the development, prognosis and drug-resistance of non-small cell lung cancer (NSCLC). Whereas, the regulatory mechanism of lncRNA TATDN1 in the cisplatin resistance of NSCLC is still not clear. Methods The expression of TATDN1, miR-451 and TRIM66 in NSCLC tissues and cell lines were detected by qRT-PCR or western blot. Immunohistochemistry (IHC) assay was performed for the detection of TATDN1 expression profile. 88 patients who underwent cisplatin treatment were followed up to 60-months for the analysis of survival rate. MTT and Flow cytometry analysis were performed for the assessment of cell survival rate, proliferation and apoptosis. Bioinformatics, Dual-Luciferase reporter were employed to analyze the interaction among TATDN1, miR-451 and TRIM66. Xenograft tumor model was constructed to verify the role of TATDN1 in NSCLC treated with cisplatin (DDP) in vivo. Results TATDN1 and TRIM66 was significantly upregulated while miR-451 was downregulated in NSCLC tissues and cell lines, especially in DDP-resistant tumor tissues and cells. Survival rates of NSCLC patients with low TATDN1 expression were improved following DDP chemotherapy. TATDN1 upregulated TRIM66 expression via sponge for miR-451. Moreover, TATDN1 knockdown improved DDP-sensitivity in NSCLC patients by regulation of miR-451/TRIM66 axis. Finally, knockdown of TATDN1 improved the sensitivity of NSCLC to DDP in vivo. Conclusions TATDN1 enhanced the DDP-tolerance of NSCLC cells by upregulating TRIM66 expression via sponging miR-451, hinting a novel regulatory pathway of chemoresistance in DDP-tolerant NSCLC cells and providing a potential therapeutic target for NSCLC patients with DDP-reistance.