Fig. 1
Identification and characterization of circBNC2 in PCa. A Heatmaps show 20 dysregulated circRNAs in PCa tumor and peritumor tissues from MiOncoCirc and Reference 37. The red and blue strips represented high and low expression, respectively. B Heatmaps show 20 dysregulated circRNAs in eight NEPC cases versus 35 CRPC cases with the highest tumor purity from Reference 37. The red and blue strips represented high and low expression, respectively. C and D Heatmaps show 20 dysregulated circRNAs in GSE140927 (C), GSE179321 (D). The red and blue strips represented high and low expression, respectively. E Venn diagram shows the crossed circRNAs among A, B, C and D. F Analysis for mRNA levels of circBNC2 in 78 paired samples of PCa were determined by RT-qPCR. G Histogram of PCa samples in which circBNC2 expression was upregulated (11/78, 14.10%), downregulated (55/78, 70.51%), or no change (12/78, 15.38%), respectively. Log2 (T/N expression) value > 1 as significantly higher expression, <-1 as lower expression, and between − 1 and 1 as no significant change. T, tumor tissue; N, normal tissue. H Analysis for mRNA levels of circBNC2 in PCa cell lines (DU145, PC3, C4-2, 22RV1, VCaP, LNCaP) and normal prostate cell line (RWPE-1). I The back-splice junction site of circBNC2 was identified by Sanger sequencing. J PCR analysis for circBNC2 and BNC2 in complementary DNA (cDNA) and genomic DNA (gDNA). K Analysis for mRNA levels of circBNC2 and the BNC2 gene after treated with RNase R in PC3 and DU145 cells. L RT-qPCR for the abundance of circBNC2 and BNC2 mRNA in PC3 and DU145 cells treated with Actinomycin D at the indicated time points. M Nuclear-cytoplasmic fractionation assay results indicated that circBNC2 was primarily localized in the cytoplasm of PC3 and DU145 cells. The 18s rRNA and the U6 genes were used as cytoplasmic and nuclear controls, respectively. N FISH experiments showed that circBNC2 predominantly located in cytoplasm in DU145 and PC3 cells, the circBNC2 probe was labeled with Cy3(red), while nuclei were stained with DAPI (blue). Scale bar = 25 μm. ns, no significance; *P < 0.05; **P < 0.01; ***P < 0.001