ObjectiveTo investigate the influence of miR-203 on the proliferation and invasion of human esophageal squamous cell carcinoma cell line Eca109. MethodsDouble-stranded mimics of miR-203 were designed and transfected into Eca109 cells with Lipofectamine 2000; Eca109 cells transfected with nonsense microRNA mimics were taken as control. The proliferation ability of Eca109 cells was determined by calculating the cell population doubling time and the percentage of apoptotic cells; the invasion ability of Eca109 cells was determined by Transwell assay. ResultsIn vitro experiment showed that, compared with the control group, Eca109 cells transfected with miR-203 mimics had a significantly longer cell population doubling time (\[26.1±0.5\] h vs \[24.2±0.6\] h, P<0.01), a higher cell apoptotic rate (\[4.5±0.4\]% vs \[3.7±0.4\]%, P<0.05), and a lower cell invasion rate (\[39.2±5.8\]% vs \[49.5±6.8\]%,P<0.05). ConclusionOur data shows that miR-203 can inhibit the proliferative and invasive abilities of Eca109 cells, suggesting that miR-203 might be a potential gene therapeutic target of human esophageal squamous cell carcinoma.