Hippo pathway-independent nuclear export of the transcriptional activator YAP regulates proliferation and migration in HCC cells

Aims: The Hippo pathway is a central regulator of organ size in different organisms. Hippo signalling is regulated by direct cell-cell interaction and contact inhibition, leading to phosphorylation and cytoplasmic retention of the transcriptional co-activator YAP (yes-associated protein). Because most human cancer cells become refractory to contact inhibition, it was suggested that this pathway and especially the nuclear accumulation of YAP is involved in liver cancer development. Methods: Expression of YAP in human normal liver, premalignant lesions (dysplastic nodules; DNs), and hepatocellular carcinoma (HCC)…