LncRNA PLAC 2 downregulated miR-21 in non-small cell lung cancer and predicted survival

BACKGROUND: LncRNA PLAC2 has been characterized as a tumor suppressive lncRNA in glioma. We investigated the role of PLAC2 in non-small cell lung cancer (NSCLC). METHODS: A total of 187 NSCLC patients were admitted by The First Hospital of Jilin University from December 2010 to December 2014. All the patients were diagnosed by histopathological approaches. Transient cell transfections, RT-qPCR, invasion, and migration ability measurement, were applied for the experiments. RESULTS: PLAC2 was down-regulated, while miR-21 was up-regulated in NSCLC tissues compared to non-cancer tissues. Low PLAC2 levels in NSCLC tissues were associated with poor survival of NSCLC patients. PLAC2 and miR-21 were inversely correlated, and PLAC 2 over-expression in NSCLC cells resulted in the down-regulation of miR-21. However, miR-21 over-expression did not significantly affect PLAC2 expression. In addition, PLAC2 over-expression resulted in decreased migration and invasion rates of NSCLC cells. MiR-21 over-expression played the opposite role and attenuated the effects of PLAC2 over-expression. CONCLUSIONS: In conclusion, lncRNA PLAC2 down-regulated miR-21 in NSCLC and inhibited cancer cell migration and invasion.