To determine if the mechanism of resistance to 5-FU treatment in CRC is driven by GLI1-mediated NBS1 expression, one normal colorectal cell line (1CT) and four CRC cell lines (SW480, HCT8, HCT116, HT29), all with varying expression levels of GLI1 and NBS1 (Figure 2A and Supplemental Figure 1), were tested for sensitivity to two concentrations of 5-FU. The gene discussed is NBN; the disease is colorectal carcinoma.