PTEN and hepatocellular carcinoma: In agreement, in our experience, the only overexpression of miR-494 in HCC xenografts does not impact on tumor growth, whereas in the setting of sorafenib treatment, overexpression of miR-494 determines resistance, suggesting the central role for miR-494/PTEN/AKT/mTOR/p27 axis in sorafenib sensitization in HCC [15].