The aim of this study was to investigate the selective cytotoxicity of the herpes simplex virus thymidine kinase/ganciclovir (HSVtK/GCV) suicide gene system controlled by the a-fetoprotein (AFP) promoter on hepatocellular carcinoma (HCC) cells in vitro.
The herpes simplex virus thymidine kinase (HSVtk) gene was transduced into an AFP-producing gastric adenocarcinoma cell line, FU97, using adenovirus vectors carrying the constructed AFP enhancer/promoter element, followed by ganciclovir (GCV) administration.
The AFP-producing but not AFP-nonproducing HCC cell lines that were transfected with the MK promoter-linked herpes simplex virus-thymidine kinase (HSV-TK) gene became susceptible to a prodrug ganciclovir to a similar degree of the HCC transfected with the enhancer-linked AFP promoter-fused HSV-TK gene.
In the present study, to achieve more selective and efficient therapeutic gene expression in hepatoma cells, we compared the therapeutic efficacies of the retroviral vectors expressing the herpes simplex virus thymidine kinase (HSV-tk) gene by the alpha-fetoprotein (AFP) enhancer/promoter in the forward (LNAFE0.3TK) and reverse (LN[AFE0.3TK]R) orientation to the vector long terminal repeats.
We previously reported that the retroviral vector expressing the herpes simplex virus-thymidine kinase gene under the control of 0.3-kb human alpha-fetoprotein (AFP) gene promoter (AF0.3) provided the cytotoxicity to ganciclovir (GCV) in high-AFP-producing human hepatoma cells but not in low-AFP-producing cells.
The aim of this study was to examine whether the human alpha-fetoprotein (AFP) enhancer could be used to induce hepatocellular carcinoma (HCC)-selective expression of the herpes simplex virus thymidine kinase (HSV-tk) gene which is under the control of the phosphoglycerate kinase (pgk) promotor.
In the present study, a retrovirus vector (LNAF0.3(E+)TK), in which herpes simplex virus thymidine kinase gene expression is under the control of a human AFP enhancer directly linked to its promoter, was constructed and compared with LNAF0.3(E+)TK.
Gene therapy using a retrovirus vector carrying herpes simplex virus thymidine kinase gene under the control of the 0.3-kb human alpha-fetoprotein (AFP) gene promoter (LNAF0.3TK virus) in combination with ganciclovir (GCV) treatment was performed in athymic mice harboring AFP-producing HuH-7 human hepatoma cells.
A recombinant AAV virus was constructed to include the selectable marker neoR gene and the herpes simplex virus (HSV)-TK gene driven by the human AFP enhancer and the albumin promoter.
We constructed a hybrid gene consisting of herpes simplex virus thymidine kinase (HSV-tk) gene under the control of the 0.3-kb human AFP gene promoter and inserted it into a retroviral vector.
Two replication-deficient adenoviruses encoding for the herpes simplex virus type-1 (HSV) thymidine kinase (TK) gene were generated in which expression of TK is under the control of either the human cytomegalovirus immediate early promoter (CMV) or the human alpha-fetoprotein (AFP) promoter/enhancer.