In this study, we found that HCC cell-secreted exosomal ANGPT2 was delivered into HUVECs (Fig. 2a, b), which is completely different from a previous report that ANGPT2 is not internalized into endothelial cells but is instead released from the cell surface into the surrounding medium in the ANGPT2/Tie2 pathway [30]; this result suggests that exosomal ANGPT2 has a novel way to interact with recipient cells that is different from the ANGPT2/Tie2 pathway of free ANGPT2. Here, ANGPT2 is linked to hepatocellular carcinoma.