miR-223 interacts with the ARTN 3'UTR and regulates endogenous ARTN protein expression. (A) The miR-223 expression vector pcDNA3.1 (+)-miR-223 reduced the activity of firefly luciferase. (B) Mutation of the binding site abolished the ability of miR-223 to inhibit the expression of the luciferase reporter. (C) The relative expression of miR-223 and artemin mRNA in esophageal carcinoma tissues. (D) The relative expression of miR-223 and artemin in esophageal carcinoma cells (KYSE150, KYSE510, TE13 and EC9706). (E) miR-223 inhibitor enhanced the expression of ARTN in EC9706 cells. (F) Overexpression of miR-223 reduced the expression of ARTN in KYSE150 cells. Data are representatives of each group or expressed as mean ± SEM of from three separate experiments.