In addition, for gene therapy, utilization of tumor-specific activity of an AFP gene promoter sequence could induce hepatoma cells to be more sensitive to ganciclovir by initiating the expression of herpes simplex virus thymidine kinase gene, a kind of exogenous gene under the control of the 0.3 kb human AFP gene promoter [117]. The gene discussed is AFP; the disease is hepatocellular carcinoma.