CXCR4 and hepatocellular carcinoma: We further found that emodin also downregulated the expression of both protein (Fig. 1F) and mRNA (Fig. 1G) for CXCR4 in a time dependent manner in Hep3B cells, thereby suggesting that the effect of emodin on CXCR4 expression is not limited to a single HCC cell line.