Title: Impaired Degradation Followed by Enhanced Recycling of Epidermal Growth Factor Receptor Caused by Hypo-phosphorylation of Tyrosine 1045 in Rbe Cells

The manuscript by Gui et al. reports that impaired EGF receptor degradation in the RBE cholangiocarcinoma cell line correlates with a specific reduction in ligand-induced phosphorylation of EGFR Y1045, the recruitment site for c-Cbl. Phosphorylation of receptor tyrosine 1068 is not compromised, so a defect in the kinase activity of the receptor is not to blame. Figure 1 compares the extent of EGFR degradation after EGF addition to the RBE cells and to immortalized cholangiocyte MMNK1 cells. Receptor degradation is clearly compromised in the RBE cells.