Retroviral transfer of herpes simplex thymidine kinase gene into glioma cells causes targeting of gancyclovir cytotoxic effect.
The thymidine kinase (tk) gene of herpes simplex virus type 1 (HSV-1) was transduced into three glioma cell lines (T98, U251MG, T9) using a retrovirus vector. The supernatants of viral producer cell line PA317/LTRNL was used for infection and three transduced cell lines (T98/LTRNL, U251MG/LTRNL, T9/LTRNL) were established. The toxicities of the anti-herpetic drugs, acyclovir and gancyclovir, were evaluated in vitro. The cytotoxicities of acyclovir and gancyclovir to the HSV-1 tk gene-transduced cells increased 100-1000 fold compared to the non-transduced parental cell lines. The cytotoxic effect of gancyclovir was higher than that of acyclovir, requiring a concentration of less than 0.31 microM to obtain 50% inhibition. Deoxyribonucleic acid analysis of the gancyclovir-treated cells demonstrated fragmentation, suggesting that apoptosis is involved in the mechanism of cell death. The HSV-1 tk gene-transduced cells were co-cultured with parental cells and treated with gancyclovir. More than 95% of cells were killed in a mixture ratio of 1:1, suggesting that the "bystander effect" operated in this system. Selective transduction of HSV-1 tk gene into glioma cells using a retroviral vector and treatment with gancyclovir is a promising therapy for patients with malignant glioma.
Kato
K
K
Department of Neurosurgery, Nagoya University School of Medicine, Japan.
Yoshida
J
J
Mizuno
M
M
Sugita
K
K
Emi
N
N
D000818:Animals; D002478:Cells, Cultured / Q000187:drug effects; D004247:DNA / Q000032:analysis; D015774:Ganciclovir / Q000009:adverse effects* / Q000494:pharmacology; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D005910:Glioma / Q000188:drug therapy / Q000473:pathology* / Q000821:virology*; D066298:In Vitro Techniques; D051381:Rats; D018139:Simplexvirus / Q000235:genetics*; D013937:Thymidine Kinase / Q000378:metabolism*
D004247:DNA; D013937:Thymidine Kinase; D015774:Ganciclovir