Gene therapy targeted by ionizing radiation.

Gene therapy used for the treatment of neoplastic diseases is not well localized. Ionizing radiation can be used to activate the transcription of exogenous genes that encode cytotoxic proteins. This may be accomplished through the use of radiation responsive elements distal to the transcription start site of such genes. We discuss this concept and describe a technique which can be used to amplify the signal initiated by localized radiation therapy. These techniques may be used to target gene therapy during the treatment of human neoplasms.