Western blot, RT-PCR and real-time quantitative RT-PCR demonstrated that over-expression of miR-9 resulted in decreased protein and transcriptional levels of cyclin D1 and Ets1 in gastric cancer cells than those transfected with negative control vector (mock) (Fig. 2B, Fig. 2C, and Fig. 2D). This evidence concerns the gene CCND1 and gastric cancer.