[Can gene transfer be used to modify the response to radiotherapy?]

Several recent studies suggest that gene transfer can be combined with irradiation to increase anti-tumor efficacy. Among genes of particular interest to be used in this combined approach are those involved in the regulation of radiation-induced lethality (apoptosis, DNA repair). Some additional aspects appear to be relatively specific to these combinations, such as the type of vector to be used (anaerobic bacteria) or the type of promoter (radio-inducible promoters). The first results obtained in mice bearing human xenograft tumors, combining gene transfer and irradiation, are encouraging, but no clinical study has been performed so far. Finally it should be pointed out, in this area as well as in cancer gene therapy in general, that progress in gene vectorisation is mandatory to optimize gene distribution within the tumor.