MiR-203 suppresses <i>BANF1</i> expression by targeting the <i>BANF1</i> 3’UTR.

<p>(A) Mature miR-203 sequences and recognition sites within the 3’UTR of <i>BANF1</i>. The seed sequence of miR-203 is underlined. The wild type (WT), mutated (Mut) and deleted (Del) <i>BANF1</i> 3’UTR recognition sites are also shown. (B) The relative luciferase activity of constructs containing the <i>BANF1</i> WT, Mut or Del 3’UTRs. Luciferase constructs were co-transfected with miRNA mimic negative control (NC, 30 nM) or miR-203 mimic (30 nM) into HeLa cells. Renilla luciferase activity was measured 36 h after incubation and normalized to firefly luciferase activity. An asterisk indicates significant downregulation of pre-miR-203 compared with the expression of the WT <i>BANF1</i> 3’UTR construct. Data are representative of three independent experiments. (C) QRT-PCR analysis of <i>BANF1</i> mRNA from CaSki and HeLa cells transfected with miRNA mimic NC (30 nM) or miR-203 mimic (30 nM). Data were normalized to the level of GAPDH mRNA, and the ratio of <i>BANF1</i>/GAPDH in the negative control was set to 1. Data are representative of three independent experiments. (D) Western blot analysis of endogenous <i>BANF1</i> expression in CaSki and HeLa cells 48 h after transfection with miR-203 mimic or inhibitor. Tubulin served as a loading control. The results are representative of three independent experiments. (E) <i>BANF1</i> expression levels in human normal cervical tissues, cervical cancer tissues and cervical cancer cell lines (CaSki and HeLa) were measured by qRT-PCR, using GAPDH as an internal control. (F) Western blot analysis of BANF1 levels in 20 paired tumor tissues (T) and adjacent normal cervical tissues (N). Tubulin served as a loading control. The five paired samples that exhibited no differences in BANF1 expression are indicated by boxes. *<i>P<</i>0.05, **<i>P<</i>0.01.