Fig. 3

The expression pattern of plasma exosomal circLPAR1 and the biological effect of exosomal circLPAR1 on colorectal cancer cellular phenotypes. The exosomes isolated from HCT116 and DLD1 cells were designated HCT116-Exos and DLD1-Exos, respectively. Exosomes were isolated from HCT116 and DLD1 cells transfected with circLPAR1/controls expression plasmid, namely, circLPAR1-Exos and NC-Exos, respectively. A The expression of exosomal circLPAR1 was detected after thawing and freezing human plasma repeatedly for 0 cycles, 2 cycles, 4 cycles, and 8 cycles. B The expression of exosomal circLPAR1 was detected after placing human plasma at room temperature for 0 h, 4 h, 8 h, and 24 h. C The expression pattern of plasma exosomal circLPAR1 across cancer-free control individuals, and patients with polyps, colorectal cancer, or other types of cancer. D Altered expression of plasma exosomal circLPAR1 in colorectal cancer patients before and after operation (op). E Top, ROC curves for CEA, CA19–9 and exosomal circLPAR1 alone or in combination. Bottom, the AUC values for CEA, CA19–9, and exosomal circLPAR1 alone or in combination. F Representative fluorescence images of colorectal cancer cells after incubation with HCT116/DLD1-Exos labelled with PKH67 (green). Scale bar, 25 μm. G The proliferation of HCT116 and DLD1 cells measured by CCK-8 assay (OD450 absorbance) after incubation with circLPAR1/NC-Exos. H The colony formation activity of HCT116 and DLD1 cells evaluated by colony formation assay after incubation with circLPAR1/NC-Exos. I The invasion and migration ability of DLD1 cells after incubation with circLPAR1/NC-Exos as detected by a transwell assay. Scale bar, 100 μm. Statistical significance was assessed using two-tailed Student’s t-test. The values represent mean ± SD. ^*P < 0.05, N. S, not significant