Conclusion
CAR10 promoted NSCLC cell migration and invasion by upregulating GJB2 and sponging miR-892a. These findings illustrated that the CAR10/miR-892a/GJB2 axis may be a novel molecular target for the treatment of NSCLC.
Methods
The expression levels of chromatin-associated RNA Intergenic 10 (CAR10), gap junction protein beta 2 (GJB2) and miR-892a in NSCLC were evaluated by reanalyzing three Gene Expression Omnibus (GEO) datasets, and performing reverse transcription-quantitative PCR, immunohistochemistry staining and Western blot analysis, accordingly. Functionally, Transwell and Matrigel assays were performed to measure changes in the migration and invasion abilities of the A549 and H1299 cell lines. The targeted binding effects between CAR10 and miR-892a, as well as between miR-892a and GJB2 were confirmed by conducting dual-luciferase reporter and RNA pull-down assays, respectively.
Results
The present study demonstrated that CAR10 was upregulated in patients with NSCLC, which was also associated with a poor prognosis. Functionally, CAR10 was confirmed to be oncogenic and promoted NSCLC cell migration and invasion, using overexpression and knockdown Transwell assays. Furthermore, GJB2 expression was revealed to be upregulated and was positively correlated with CAR10 expression in NSCLC. A further mechanistic study revealed that GJB2 was a downstream target of CAR10, which induced the migration and invasive potential of the A549 and H1299 cell lines. More specifically, miR-892a was found to serve as a bridge between CAR10 and GJB2, via similar miRNA response elements. The RNA pull-down and luciferase assays indicated that miR-892a directly binds both CAR10 and GJB2.