ISPO

Published in Cancer Detection and Prevention 2000; 24(Supplement 1).

Combination of hyperthermia and TNF-alpha gene therapy driven by heat-inducible promoter gadd 153

A Ito, M Shinkai PhD, IA Bouhon PhD, H Honda PhD, T Kobayashi PhD

Dept Biotechnology, Graduate School of Engineering, Nagoya University, Nagoya, Japan

AIM: TNF-alpha gene located under gadd (the Growth Arrest and DNA Damage) 153 promoter system was constructed and the combination with hyperthermia was investigated in vitro and in vivo. METHODS: For in vitro experiment, the TNF-alpha gene was introduced into human glioma U251-SP cells by lipofection. The cells were heated by water bath at 43°C or 45°C for 1h. The cytotoxicity and TNF-alpha concentration were evaluated by cell counts and ELISA. For in vivo experiment the intracellular hyperthermia was done using magnetite cationic liposomes (MCL). U251-SP cells were subcutaneously transplanted in the femur of athymic nude mice. The TNF-alpha gene and MCLs were directly injected into the tumor, and then alternating magnetic field was applied for hyperthermia. RESULTS: TNF-alpha production per cell at 43°C or 45°C reached 4.3 or 240 times the basal level. The cytotoxicity of the transfected cells at 43°C or 45°C was 81% or 99.9%. In in vivo experiment, tumor growth was strongly inhibited for 30 days by combination of hyperthermia with TNF-alpha gene. TNF-alpha expressing cells were observed around necrotic area formed by hyperthermia in immunohistochemical stained specimen of the tumor. CONCLUSIONS: Combination of hyperthermia and TNF-alpha gene therapy driven by heat-inducible promoter gadd 153 was found to be very effective treatment for cancer.

KEY WORDS: hyperthermia, TNF-alpha, gadd 153, glioma, heat-inducible promoter.

For more information, contact h001401d@mbox.media.nagoya-u.ac.jp

Paper presented at the International Symposium on Impact of Biotechnology on Cancer Diagnostic & Prognostic Indicators; Geneva, Switzerland; October 28 - 31, 2000; in the section on synergistic therapies.

http://www.cancerprev.org/Journal/Issues/24/101/410/3693