Figure 3.

miR-21 directly targets MKK3. (A) Alignment of the interaction sites in the human 3′-UTR of MKK3 gene and the mutated 3′-UTR of MKK3 is highlighted in red. The target interaction between miR-21 and MKK3 was tested using a dual-luciferase assay in 293T cells. *P<0.05. (B) Reverse transcription-quantitative PCR and western blot analyses were used to examine the expression levels of MKK3 and miR-21 in A2058 cells, following transfection with miR-21 mimic and inhibitor. *P<0.05 vs. NC. (C) Linear regression of MKK3 expression and miR-21 expression in the 15 pairs of tumor tissues. The results are presented as the mean ± standard deviation of at least three independent experiments performed in triplicate. MKK3, mitogen-activated protein kinase kinase 3; miR-21, microRNA-21; UTR, untranslated region; NC, negative control; mut, mutant.