Various expression levels of Nbs1 have been detected in three HCC cell lines (HepG2, Hep-3B and HepG2.2.15) and one ICC cell line HCCC-9810 (Figure 5), and notably, Nbs1 null mutant cell lines is not viable due to the functional importance of MRN complex in cells. The gene discussed is NBN; the disease is intrahepatic cholangiocarcinoma.