Treatment of glioblastoma by direct inoculation of concentrated high titer-recombinant retrovirus carrying the herpes simplex virus thymidine kinase gene.
We prepared retroviruses carrying the lacZ gene or herpes simplex virus thymidine kinase (HTK) gene with titers of 1.4-2.5 x 10(11) colony-forming units (cfu)/ml, and stereotaxically inoculated only 3 microliters of the retroviruses into a mouse glioma model. This resulted in highly efficient transduction in vivo. The transduced glioma cells migrated far from the implantation site, potentiating the induction of the remarkable bystander effect. Following repetitive ganciclovir (GCV) intraperitoneal injection, effective killing of glioma cells in the mouse brain was observed. The transduction efficiency was nearly as high as that observed for the implantation of high-titer retrovirus-producing fibroblasts. Eighty per cent of brain tumor-bearing mice were completely cured by our treatment protocol using concentrated HTK-harboring retroviruses. Our results suggest that repeated inoculations of high-titer retroviruses carrying the HTK gene followed by GCV treatment may be a promising strategy for the clinical treatment of malignant gliomas. To achieve further safety in the gene therapy of glioma, genes abundantly expressed in human glioblastoma were searched by the Serial Analysis of Gene Expression (SAGE) technique. Among the top-147 most expressed tags in glioblastoma, we found a tag, TTTTGGGTAT, originated from an unidentified gene, which was not detected in human astrocyte cultures. Real-time quantitative RT-PCR showed that MAGE-E1 expression was 2.6-15 fold enriched in glioblastoma relative to human astrocytes. Expressed Sequence Tags (ESTs) containing this tag were homologous to melanoma-associated antigen gene (MAGE) family, and this new cDNA, named MAGE-E1, was cloned by 5'-rapid amplification of cDNA ends (RACE) technique. MAGE-E1 expression was enriched in glioblastoma and low in other cancers, and MAGE-E1 expression was detected only in brain and ovary among normal tissues. These results indicate that MAGE-E1 is a novel and glioma-specific member of MAGE family, which can be applied to glioma-specific gene transduction.
Ikenaka
K
K
National Institute for Physiological Sciences, Okazaki National Research Institutes. ikenaka@nips.ac.jp
Sasaki
M
M
Tamura
K
K
Tamura
M
M
Miyao
Y
Y
Nanmoku
K
K
Kawano
Y
Y
Nakahira
K
K
Yoshimine
T
T
Shimizu
K
K
D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics; D020224:Expressed Sequence Tags; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors; D005909:Glioblastoma / Q000235:genetics / Q000628:therapy*; D006801:Humans; D051379:Mice; D012190:Retroviridae / Q000235:genetics*; D018139:Simplexvirus / Q000201:enzymology*; D013937:Thymidine Kinase / Q000235:genetics*
D000951:Antigens, Neoplasm; C430404:MAGE-E1 antigen, human; D013937:Thymidine Kinase