Furthermore, our previous results indicated that HBV-X protein induced the expression of AFP in human normal liver cells, which correlated to CXCR4 expression in human hepatoma cells[31], and accumulated evidences showed that the mTOR/CXCR4 signal axis is closely associated with the promotion of cancer cell metastasis[32]. The gene discussed is CXCR4; the disease is hepatocellular carcinoma.