MAP2K3 and hepatocellular carcinoma: Consistent with this finding, the result present in this study for the first time demonstrated that MAP2K3 was a novel target for miR-21 in HCC, in which MAP2K3 expression was inversely correlated with the miR-21, suggesting an underlying mechanism by which the elevated miR-21 post-transcriptionally down-regulates MAP2K3 signaling in HCC development.