Similarly, knocking down expression of CCND1 (si CCND1 + vector) could mimic tumor suppressive effect of miR-503 mimic (mimic + vector) on ESCC cell migration and invasion, whereas overexpression of CCND1 (mimic + CCND1) could partially reverse the tumor suppressive effect of miR-503 on ESCC cell lines (Figure6C). Here, CCND1 is linked to esophageal squamous cell carcinoma.