LncRNA‐DANCR contributes to lung adenocarcinoma progression by sponging miR‐496 to modulate mTOR expression

Long non-coding RNAs (lncRNAs) have emerged as new and important regulators of pathological processes including tumour development. In this study, we demonstrated that differentiation antagonizing non-protein coding RNA (DANCR) was up-regulated in lung adenocarcinoma (ADC) and that the knockdown of DANCR inhibited tumour cell proliferation, migration and invasion and restored cell apoptosis rescued; cotransfection with a miR-496 inhibitor reversed these effects. Luciferase reporter assays showed that miR-496 directly modulated DANCR; additionally, we used RNA-binding protein immunoprecipitation (RIP) and RNA pull-down assays to further confirm that the suppression of DANCR by miR-496 was RISC-dependent. Our study also indicated that mTOR was a target of miR-496 and that DANCR could modulate the expression levels of mTOR by working as a competing endogenous RNA (ceRNA). Furthermore, the knockdown of DANCR reduced tumour volumes in vivo compared with those of the control group. In conclusion, this study showed that DANCR might be an oncogenic lncRNA that regulates mTOR expression through directly binding to miR-496. DANCR may be regarded as a biomarker or therapeutic target for ADC.