With this schedule we noted a mild and transitory toxicity which was quickly reversible after treatment. Two rats in the WBI group lived more than 120 days. They were sacrificed and their brain was removed; there was no sign of tumor. It is not

possible to determine whether there was a technical problem during the tumor cells implantation or if the animals achieved a complete response after irradiation. There is a paucity of experimental data in literature on rat radiobiology. Different energy sources are used. Some groups work with a dedicated irradiator for small animals in their laboratory. This type of irradiator uses137Cesium or60Cobalt source and delivers gamma-rays [[9, 19, 20] and [21]]. As Lamproglou, even though his work was on normal brain [12], we decided to treat our rats with linear accelerator used in clinical practice. Animal irradiation MLN2238 research buy may be difficult to manage because of the limited availability of accelerators but the main advantage is to deliver the same energy type as in clinical practice. There are other advantages of using a nonradioactive x-ray-producing irradiator such as avoiding the increasing number of radioprotection controls as well as the potential source

hazard, disposal ASK inhibitor and replacement; nonetheless the expected efficacy is the same whatever the radiation source chosen. This work does not answer the crucial question of optimal therapeutic regimen as it was conducted before our studies into the efficacy of local chemotherapy concomitant to radiation therapy in 9L glioma [22]. Another study confirms the reproducibility of the model as we obtained the same eltoprazine improvement in survival in the radiation group compared to the untreated group [18]. Therefore, this radiation therapy protocol has the potential to induce strong tumor debulking and facilitate concomitant chemotherapy treatment. Conclusion Many models of radiation therapy for

rat glioma are available, with different schedules. We describe a reproducible paradigm of fractionated radiotherapy for rat bearing a brain tumor, which reflects clinical practice, with a good compromise between feasibility and adaptation to chemotherapy radiosensitization studies. Acknowledgements The authors would like to thank Pierre Legras and Jerome Roux (Service Commun d’Animalerie Hospitalo-Universitaire, Angers, France) for skillful technical support with animals and the Radiotherapy Department of Paul Papin Center for technical help. Special thanks to Rachel Holden for her precious help. This work was supported by “”La Fondation pour la Recherche Médicale”". References 1.