Fig. 1
Profiling of circRNAs in tissues and selection of exosomal circLPAR1. The exosomes isolated from FHC, HCT116 and DLD1 cells were designated FHC-Exos, HCT116-Exos and DLD1-Exos, respectively. A The expression pattern of circRNAs in 52 pairs of colorectal tumors and normal adjacent tissues (NATs). The grey line shows the relative expression of circRNAs in each tissue (the log2 (ratios)). The blue line shows the average relative expression of all circRNAs in each tissue (the log2 (ratios)). The X-axis represents colorectal cancer tissues (left) and NATs (right). B Spliced length distributions (nt) of circRNAs as determined by RNA-Seq. C Pie chart showing the percentage of circRNAs derived from different genomic regions. D Volcano plots of differentially expressed circRNAs (fold-change (FC) ≥ |2| and P < 0.005). E The cluster heat map of five differentially expressed circRNAs. F The characteristics of differentially expressed circRNAs available in the exoRBase 1.0 database in 2018. G The call rate of differentially expressed circRNAs identified by RNA-Seq. H Differential expression of hsa_circ_0087960 between normal colorectal mucosal cells (FHC) and colorectal cancer cells (HCT116 and DLD1). Statistical significance was assessed using two-tailed Student’s t-test. I The size distributions of FHC/HCT116/DLD1-Exos. Exosomes were identified by NanoFCM. The X-axis represents exosome size and the Y-axis represents exosome number. J Visualization of purified FHC/HCT116/DLD1-Exos. TEM was performed to confirm the shape of the exosomes. Scale bar, 100 nm. K Western blot showing the exosome-specific markers TSG101 and Alix. L Differential expression of exosomal circLPAR1 between the FHC-Exos and HCT116/DLD1-Exos groups. Statistical significance was assessed using two-tailed Student’s t-test. The values represent mean ± SD.*P < 0.05