DKK-3 is the direct target of miR-183 in renal cell carcinoma. (A) The miR-183 binding site in the DKK-3 3′-UTR, as predicted by TargetScan. The upper sequence is miR-183, the middle sequence is the target WT, and the bottom sequence is the target-mutated sequence. (B) The firefly luciferase activity in the 786-O cell line was detected following co-transfection of the WT or MUT 3′-UTR (100 ng) with the miR-183 mimic or mimic-NC (50 nmol/l). The firefly luciferase activity of each sample was normalized to Renilla luciferase activity. *P<0.05 vs. mimic NC. (C) Reverse transcription-quantitative polymerase chain reaction analysis of the relative mRNA levels of DKK-3 following miR-183 inhibitor transfection. (*P<0.05 vs. anti-miR-183, as determined by Student's t-test). (D) Western blot analysis of DKK-3 protein expression levels following transfection with a miR-183 inhibitor. DKK-3, Dickkopf-related protein 3; miR, microRNA; WT, wild-type; MUT, mutant; UTR, untranslated region; NC, negative control.