Fig. 4

PTEN is a direct target of miR-221. a Binding sequences for miR-221 in the 3′-UTR of PTEN, and the mutations in the 3′-UTR of PTEN are presented. b Luciferase activity of the wild type PTEN 3′-UTR (Wt) and mutant T PTEN 3′-UTR (Mut) co-transfected with miR-221 mimics or a negative control (miR-NC) was measured. c RT-qPCR analysis of PTEN mRNA in A431 and SCC13 cells following transfection with miR-221 inhibitor or mimics. d Western blotting was used to detect PTEN protein expression in A431 and SCC13 cells following transfection with miR-221 inhibitor or mimics. e Relative PTEN mRNA expression levels were determined using RT-qPCR in CSCC tissues and adjacent non-tumorous gastric mucosae tissues. f Analysis of correlation between miR-221 and PTEN mRNA expression in CSCC tissues