To determine whether the internalization of exosomal ANGPT2 associates with endocytosis, we used the endocytosis inhibitors nystatin and amiloride to treat HUVECs before coculture [32], and we found that the internalization process of exosomal ANGPT2 was blocked (Fig. 2c, d), suggesting that HCC cell-secreted exosomal ANGPT2 is delivered into HUVECs via exosome endocytosis. This evidence concerns the gene ANGPT2 and hepatocellular carcinoma.