Figure 5. circRNA_100859 acts as a ceRNA to sponge miR-217. (A) The potential binding sequences of circRNA_100859 to miR-217. (B) The relative luciferase activities were estimated after co-transfection with circRNA_100859-wt or mut and miR-217 mimics or miR-217 NC were analyzed. **P<0.01 vs. empty vector+NC. #P>0.05 vs. mut+mimic. (C) miR-217 was dramatically down-regulated in colon cancer tissues (n=50), *P < 0.05, **P < 0.01 versus adjacent non-cancer tissues. (D) Pearson's analysis suggested that the negative correlation between circRNA_100859 and miR-217. (E, F) RT-qPCR demonstrated that circRNA_100859 overexpression inhibited miR-217 expression, while circRNA_100859 silencing increased miR-217 expression. *P < 0.05, **P < 0.01 versus corresponding NC group.