First, we transfected HCC-1599, MB-157, MDA-MB157 as well as three other TNBC and retinoid-insensitive cell lines (MDA-MB231; HCC-38; MDA-MB436) with a reporter construct, containing a luciferase cDNA driven by the minimal promoter of the NOTCH1 target-gene, HES1 [29,30]. Here, NOTCH1 is linked to hepatocellular carcinoma.