miR-30a-3p is downregulated in EC tissues and cell lines. (A) miR-30a-3p expression in EC tissues and paired normal tissues as determined by RT-qPCR. (B) miR-30a-3p expression in EC cell lines (EC9706 and EC109) and a human esophageal epithelial cell line (HET-1A) as determined by RT-qPCR. (C) Following transfection with miR-30a-3p mimics or miR-30a-3p inhibitors in EC9706 and EC109 cells, the efficiency of transfection was evaluated by RT-qPCR. Data are presented as the mean ± standard deviation of three independent experiments, each performed in triplicate. **P<0.01 vs. HET-1A or control. ##P<0.01 vs. the NC group. EC, esophageal carcinoma; miR, microRNA; NC, negative control; RT-qPCR, reverse transcription-quantitative polymerase chain reaction.