HNF4A and hepatocellular carcinoma: HNF1α and HNF4α had positive feedback regulation, mutations of Y122C, R229Q and V259F in the POUC domain of HNF1α inhibited its activity and disrupted the binding to the HNF4α promoter, resulting in down-regulation of HNF4α and other HNF1α target genes, as well as disruption of HNF4α-HNF1α transcriptional network, thus triggering the development of HCC (17).