Fig. 1. miR-451a is downregulated in serum-derived exosomes from hepatocellular carcinoma (HCC) patients. A, Electron microscope images of exosomes derived from HCC patient serum by ultracentrifugation (top) and isolation regent (bottom). B, Expression of molecular markers of exosomes, including CD63, Alix, and CD81, as determined by western blotting. C, Screening strategy for differentially expressed exosomal miRNome in HCC patient serum. D, The expression level of exosomal miR-451a was assessed by quantitative PCR in normal and HCC serum. E, The expression level of miR-451a was assessed by quantitative PCR in HCC tissues and paired tumor adjacent tissues. *P<0.05, ***P<0.001.