Figure 1. The expression, structure and characteristics of circSLCO1B7 in HCC. (A) The heatmap was used to screen circSLCO1B7 with low expression in HCC. (B) qRT–PCR analysis of the expression of circSLCO1B7 in HCC tissues. (C) qRT–PCR was used to detect the expression of circSLCO1B7 in the plasma of HCC patients. (D) The expression of circSLCO1B7 in HCC cells (SK-HEP-1, Li-7, PLC/PRF/5, Hep3B2.1-7 and HuH-7) compared to LO2 cells was detected by qRT–PCR. (E) Sequencing of qRT–PCR amplification products confirmed the circular site of circSLCO1B7. (F) Agarose gel electrophoresis showing the expression of circSLCO1B7 and GAPDH were amplified by divergent primers and convergent primers using cDNA and gDNA in SK-HEP-1 and PLC/PRF/5 cells. (G) The levels of circSLCO1B7 and SLCO1B7 in SK-HEP-1 and PLC/PRF/5 cells treated with RNase R were analysed by qRT–PCR. (H) FISH assay verified the location of circSLCO1B7 in PLC/PRF/5 cells. (I) qRT–PCR showed circSLCO1B7 was located in nuclear or cytoplasm. All data are presented as the means ± SD. *P < 0.05, **P < 0.01, ****P < 0.0001.