For example, the HCC marker gene AFP is specifically and highly expressed in HepG2 cells, and it is wrapped within a RAID consisting of strong RNAPII binding and chromatin looping; whereas the normal liver genes CXCL2 and AREG are only expressed in THLE2 cells and interconnected within a large RAID configuration (Figure 1G). This evidence concerns the gene AFP and hepatocellular carcinoma.