RNF31 was overexpressed in PA tissues and regulated directly by miR-378. (A) Reverse transcription-quantitative polymerase chain reaction assay of RNF31 expression in PA tissues. The mean level of RNF31 expression in PA tissues (n=25) was significantly higher compared with expression in corresponding adjacent normal tissues (n=25). Data are presented as the mean ± standard deviation from three independent experiments. *P<0.01 vs. normal tissues. (B) Sequence alignment of miR-378 and 3′ untranslated region of RNF31 using mirco-RNA.org and Luciferase reporter assay. Effects of miR-378 mimics and miR-378 inhibitors on the expression levels of RNF31 (C) mRNA and (D) protein. Data are presented as the mean ± SD from three independent experiments. *P<0.01 vs. control group. SD, standard deviation; PA, pituitary adenoma; miR, microRNA; RNF31, ring finger protein 31; WT, mutated; WT, wild-type.