HNF4A and hepatocellular carcinoma: Conversely, ectopic expression of HNF4α in fibroblasts has been shown to induce a mesenchymal-to-epithelial transition (MET) [5] and in poorly differentiated and invasive hepatocellular carcinoma (HCC) cells to restore an epithelial differentiated phenotype, thereby reducing both proliferation and invasiveness [7,8,9].