PTEN and hepatocellular carcinoma: The drug-resistant HCC cell line Bel/5-FU delivers miR-32-5p to the sensitive HCC cell line Bel7402 by exosomes to reduce PTEN expression,which in turn activates the PI3K/Akt pathway leading to multidrug resistance by modulating angiogenesis and epithelial-to-mesenchymal transition (73).