Figure 4.

SUFU is the direct target of miRNA-324-5p. (a) The expression level of SUFU was up-regulated by miRNA-324-5p inhibitors in BGC-823 and down-regulated by miRNA-324-5p mimics in HFE-145 cells. (b) The predicted binding sites of miRNA-324-5p on the 3’UTR region of SUFU and their corresponding mutant sites in luciferase reporters are shown. (c) HFE-145 and BGC-823 cells were co-transfected with miRNA-324-5p mimics/inhibitors and SUFU 3’UTR WT (wild-type)/Mutant reporter plasmids. SUFU 3’ UTR dependent luciferase activities were reduced or increased by miRNA-324-5p mimics or inhibitors, respectively,*p < 0.05. (d) SUFU expression level in 60 paired GC tissues was determined by qRT-PCR and SUFU was down expressed in GC. (e)RNA-seq analysis of SUFU mRNA levels in 368 GCs and 35 normal tissues queried from TCGA showed that SUFU was down-regulated in GC, *p < 0.05. (f) Spearman’s correlation analysis showed that there was a negative correlation between SUFU and miRNA-324-5p expression in 60 tested tissues, *p < 0.001. (g) Expression correlation analysis was performed between miRNA-324-5p and SUFU in GCs from TCGA database (n = 368), r = −0.108, p = 0.038. SUFU expression was negatively correlated with that of miRNA-324-5p