MiR-205 directly targets ZEB2 and miR-205 expression level in invasive ESCC tumors with poor differentiation is higher than in intraepithelial ESCC tumors. Activities of the firefly luciferase with the ZEB1 or ZEB2 3'-untranslated region (UTR) in the presence of co-transfected negative control (white bar) or miR-205 precursor (black bar). The luciferase activities were shown as the ratio of firefly to Renilla luciferase activity and measured after 24 h in triplicates (A). The miR-205 expression levels in ESCC tumor samples and matched non-cancerous surrounding mucosa of the esophagus were measured using quantitative RT-PCR. There are no significant difference in the miR-205 expression levels between the ESCC tumors (white bars) and their paired surrounding non-tumor tissues (black bars), though miR-205 is highly expressed in the tumors of 16 of 28 cases examined (B). No significant difference was observed between intraepithelial and invasive ESCC samples (C). The miR-205 expression levels did not differ among the histological subclasses of ESCC differentiation, but invasive ESCC with poor differentiation showed more significantly increased expression of miR-205 than intraepithelial ESCC (D).