modulates PTEN tumor suppressor gene expression. To evaluate the biological significance of miR-21 overexpression in CCC, we used a loss-of-function antisense approach. An antisense miR-21 oligonucleotide (ODN) was used to knock down miR-21 expression in RMG-II cells. (A) Efficiency of RMG-II cell transfection was confirmed by real- time RT PCR. PTEN mRNA expression was increased by knockdown of miR-21 in RMG-II cells. Western blot analysis showing that PTEN expression was increased in RMG-II cells upon inhibition of miR-21. (B)
MiR-21 directly targets the 3'-UTR of PTEN mRNA. The activity of luciferase in the pGL3 wild-type PTEN 3′-UTR was downregulated compared to pGL3 mutant-type PTEN 3’-UTR and the pGL3 control in RMG-II cells. P <0.05 according to the t-test.