EV-miR-21 from HCC cells triggers conversion of normal HSCs into CAFs by targeting PTEN, and activated CAFs in turn promote angiogenesis in vitro and in vivo by secreting angiogenic cytokines, including TGF-β, VEGF, bFGF, MMP2 and MMP9 [219]. Here, PTEN is linked to hepatocellular carcinoma.