Survival of rats bearing advanced intracerebral F 98 tumors after glutathione depletion and microbeam radiation therapy: conclusions from a pilot project

Autor: Schueltke, E., Brauer-Krisch, E., Blattmann, H., Requardt, H., Laissue, J. A., Hildebrandt, G.
Přispěvatelé: European Synchrotron Radiation Facility (ESRF)
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: Radiation Oncology, Vol 13, Iss 1, Pp 1-11 (2018)
Radiation Oncology
Radiation Oncology, BioMed Central, 2018, 13, pp.89-1-89-11. ⟨10.1186/s13014-018-1038-6⟩
'Radiation Oncology ', vol: 13, pages: 89-1-89-11 (2018)
ISSN: 1748-717X
DOI: 10.1186/s13014-018-1038-6
Popis: International audience; Background: Resistance to radiotherapy is frequently encountered in patients with glioblastoma multiforme. It is caused at least partially by the high glutathione content in the tumour tissue. Therefore, the administration of the glutathione synthesis inhibitor Buthionine-SR-Sulfoximine (BSO) should increase survival time.Methods: BSO was tested in combination with an experimental synchrotron-based treatment, microbeam radiation therapy (MRT), characterized by spatially and periodically alternating microscopic dose distribution. One hundred thousand F98 glioma cells were injected into the right cerebral hemisphere of adult male Fischer rats to generate an orthotopic small animal model of a highly malignant brain tumour in a very advanced stage. Therapy was scheduled for day 13 after tumour cell implantation. At this time, 12.5% of the animals had already died from their disease.The surviving 24 tumour-bearing animals were randomly distributed in three experimental groups: subjected to MRT alone (Group A), to MRT plus BSO (Group B) and tumour-bearing untreated controls (Group C). Thus, half of the irradiated animals received an injection of 100 mu M BSO into the tumour two hours before radiotherapy. Additional tumour-free animals, mirroring the treatment of the tumour-bearing animals, were included in the experiment. MRT was administered in bi-directional mode with arrays of quasi-parallel beams crossing at the tumour location. The width of the microbeams was approximate to 28 mu m with a center-to-center distance of approximate to 400 mu m, a peak dose of 350 Gy, and a valley dose of 9 Gy in the normal tissue and 18 Gy at the tumour location; thus, the peak to valley dose ratio (PVDR) was 31.Results: After tumour-cell implantation, otherwise untreated rats had a mean survival time of 15 days. Twenty days after implantation, 62.5% of the animals receiving MRT alone (group A) and 75% of the rats given MRT + BSO (group B) were still alive. Thirty days after implantation, survival was 12.5% in Group A and 62.5% in Group B. There were no survivors on or beyond day 35 in Group A, but 25% were still alive in Group B. Thus, rats which underwent MRT with adjuvant BSO injection experienced the largest survival gain.Conclusions: In this pilot project using an orthotopic small animal model of advanced malignant brain tumour, the injection of the glutathione inhibitor BSO with MRT significantly increased mean survival time.
Databáze: OpenAIRE
Nepřihlášeným uživatelům se plný text nezobrazuje