We found that the protein level of Dlg5 was regulated by the ubiquitin proteasome system, as proteasome inhibitor MG132 treatment resulted in the accumulation of endogenous Dlg5 in two HCC cell lines and exogenous expressed Flag-Dlg5 in 293T cells (Fig. 1a–c). The gene discussed is DLG5; the disease is hepatocellular carcinoma.