EGFR and cancer: While TGR5 acts with cytoprotective effects in nontumoral cholangiocytes, in malignant cells, the same receptor may confer apoptosis resistance and enhance proliferation through an increase in reactive oxygen species (ROS) and may thus modulate cancer progression, since it has been linked to cholangiocyte proliferation induced by epidermal growth factor receptor (EGFR) and ERK1/2.