Considering the ectopic expression of cyclin E2 (CYCE2, Gene ID: 9134) in lung tumor tissues and its role in cell cycle G1/S transition and proliferation, it was hypothesized in this study that the expression of hsa-miR-30d-5p which targets cyclin E2 might be potentially applied as a tumor marker in NSCLC. Here, CCNE2 is linked to non-small cell lung carcinoma.