In summary, our results demonstrated that C/EBPα, as the downstream factor of TRIB2, was up-regulated after miR-511 (or miR-1297) treatment, and that miR-511 (or miR-1297) acts as a tumor suppressor genes to induce A549 cell apoptosis by targeting the oncogene TRIB2. Study of the TRIB2 oncogene and its related miRNAs miR-511 and miR-1297) may provide new targets for lung cancer therapy. The gene discussed is CEBPA; the disease is lung cancer.