Previous studies have shown that the cloned proximal segment of the OVA promoter lacking the major regulatory elements of SDRE and NRE, can significantly increase (up to 17-fold) the chloramphenicol acetyltransferase (CAT) gene activity on a plasmid construct in LMH cells (a chicken hepatoma cell line) and chicken primary oviduct cells, and this increase occurs in an estrogen-independent manner [27, 29]. Here, CAT is linked to hepatocellular carcinoma.