Purpose: Emerging evidence suggests that many differentially expressed long non-coding RNAs (lncRNAs) are involved in tumorigenesis. However, the functional roles of these transcripts and the mechanisms responsible for their deregulation in non-small-cell lung cancer (NSCLC) remain elusive. Here, we identified a novel lncRNA (lncRNA 1308), which was significantly upregulated in NSCLC tissues and investigated its biological function and potential molecular mechanism.
Methods: Differences in the lncRNA expression profiles between NSCLC and tumor-adjacent normal tissues were assessed by lncRNA expression microarray analysis. The microRNA in vivo precipitation (miRIP) method was used to identify the targeting microRNAs (miRNAs) on lncRNA 1308, and luciferase reporter assays were performed. Loss-of-function studies were used to explore the effect of lncRNA 1308 on lung carcinogenesis in NSCLC cells.
Results: The novel lncRNA 1308 was upregulated in NSCLC tissues and cell lines. By using biotin-labeled lncRNA 1308 for miRIP in NSCLC cells and dual-luciferase reporter assays, the results suggested that miRNA-124 was associated with lncRNA 1308. Furthermore, the expression of a disintegrin and a metalloproteinase 15 (ADAM 15) was downregulated in NSCLC cells when silencing of lncRNA 1308, the target of oncogenic miR-124, inhibits NSCLC cell proliferation and invasion. Conversely, the expression of ADAM 15 was significantly increased, when inhibiting the expression of miR-124, and alleviated cell invasion inhibition.
Conclusion: The results suggested that lncRNA 1308 may function as a competing endogenous RNA (ceRNA) for miR-124 to regulate cell invasion through the miR-124/ADAM 15 signaling pathway, indicating that lncRNA 1308 plays an important role in the disease progression of NSCLC.
Keywords: ADAM 15; competing endogenous RNA; lncRNA 1308; lung cancer; miR-124.