Fig. 5

CircMID1 and MID1 act as ceRNAs in PCa through regulation of miR-506-3p. A The expression level of MID1 in benign prostatic hyperplasia (BPH, n = 31) and PCa tissues (n = 56) determined by qRT-PCR. (B-C) Pearson’s correlation analysis was used to analyze the relationships between MID1 mRNA and miR-506-3p (R = -0.4346, P = 0.0008, B), and MID1 mRNA and circMID1 (R = 0.424, P = 0.0011, C). D Potential binding site of miR-506-3p at the 3′-UTR of human MID1 mRNA is shown. Red color indicates the sequence of the mutated miR-506-3p-binding site. E PC3 and DU145 cells were cotransfected with miR-506-3p mimic or control mimic and luciferase reporter vector containing wild-type (WT) or mutated miR-506-3p-binding site (MUT) at MID1 3′-UTR. Luciferase reporter assays were performed. ^*P < 0.05; ^**P < 0.01, ^* vs. MID1 3′-UTR-WT + miR-NC. F, G PC3 and DU145 cells were transfected with miR-506-3p mimic or anti-miR-506-3p and their corresponding controls (miR-NC or anti-miR-ctl), and the mRNA (F) and the protein (G) expression levels of MID1 were analyzed by qRT-PCR and western blotting, respectively. ^*,#P < 0.05; ^**,##P < 0.01, ^* vs. miR-NC, ^# vs. Anti-miR-ctl. H PC3 and DU145 cells were transfected with si-NC, si-MID1, si-MID1 and anti-miR-ctl or anti-miR-506-3p, and the expression of circMID1 was determined by qRT-PCR. ^*,#P < 0.05; ^**,##P < 0.01, ^* vs. si-NC, ^# vs. si-MID1. I, J PC3 and DU145 cells were transfected with si-control, si-circMID1, or si-circMID1 and Anti-miR-ctl or Anti-miR-506-3p, and the mRNA (I) and protein (J) expression of MID1 were determined by qRT-PCR and western blotting, respectively. All experiments were conducted at least three times (^**, ^##P < 0.01). ^* vs. si-control, ^# vs. si-circMID1