SLC38A1 and hepatocellular carcinoma: YAP1 and transcriptional coactivator with PDZ-binding motif (TAZ) up-regulates the expression of amino acid transporter solute carrier family 38 member 1 (SLC38A1) and solute carrier family 7 member 5 (SLC7A5), increase amino acid uptake, activate mammalian rapamycin complex 1 (mTORC1), and stimulate the proliferation of HCC cells.