MiR-491 attenuates cancer stem cells-like properties of hepatocellular carcinoma by inhibition of GIT-1/NF-κB-mediated EMT.

Hepatocellular carcinoma (HCC) is the most common liver malignancy. Current standard practices for treatment of HCC are less than satisfactory because of CSCs-mediated recurrence. For this reason, targeting CSCs, or cancer cells with CSCs-like properties, is a new approach for HCC treatment. As we reported previously, microRNA-491 (miR-491) is lower expressed in poorly differentiated HCC tissues relative to well-differentiated HCC tissues. Here, we further evaluate the effects of miR-491 on the CSCs-like properties by using HCC cell lines and HCC tissue samples. Our data showed that miR-491 had a negative relationship with CSCs-like properties both in cell lines and tissue samples of HCC. Further, miR-491 levels of non-recurrence HCC tissues were higher than those of recurrence HCC tissues. In HCC cell lines, nuclear factor kappa B (NF-κB)/snail pathway was involved in the epithelial to mesenchymal transition and the maintenance of CSCs-like properties. Overexpression of miR-491 targeted G-protein-coupled receptor kinase-interacting protein 1 (GIT-1), which blocked the activation of NF-κB by the inhibition of extracellular signal-regulated kinases (ERKs). Such process attenuated the CSCs-like properties in HCC cells. Our results point to a previously undefined mechanism by which miR-491 decreases CSCs-like properties and help to identify potential targets for the therapy of HCCs.