AREG and hepatocellular carcinoma: In hypoxic HCC cells and in the hypoxic regions of the human HCC xenografted models, YAP was predominantly localized to the nucleus, which was accompanied by increased mRNA level of the YAP target genes CTGF and AREG. The small interfering RNA (siRNA)-mediated suppression of YAP expression sensitized the hypoxic HCC cells to the SN38 treatment.