INFLUENCE OF DOSE RATE ON THE CELLULAR RESPONSE TO LOW- AND HIGH-LET RADIATIONS

Frontiers in Oncology

卷:6

Anne-Sophie eWozny¹  Gersende eAlphonse¹  Claire eRodriguez-Lafrasse¹  Delphine ePoncet¹  Michael eBeuve²  Etienne eTesta²  Nicolas eMagne³  Chloé eRancoule³  Jean-Baptiste eGuy³  Priscillia eBattiston-Montagne⁴  Stéphanie eSimonet⁴ 

[1] Hospices civils de Lyon;

[2] IPNL-LIRIS-CNRS-IN2P3;

[3] Lucien Neuwrith Cancer Institute;

[4] Univ Lyon, UCBL1, UMR/CNRS 5822;

关键词: DNA double-strand breaks;    dose rate;    photon;    Carbon ion;    High and low LET irradiations;    Head-and-Neck Squamous Cell Carcinoma.;   

DOI  :  10.3389/fonc.2016.00058

来源: DOAJ

【 摘 要 】

Nowadays, head and neck squamous cell carcinoma (HNSCC) treatment failure is mostly explained by loco-regional progression or intrinsic radioresistance. Radiotherapy has recently evolved with the emergence of heavy ion radiations or new fractionation schemes of photon therapy which modify the dose-rate of treatment delivery. The aim of the present study was then to evaluate the in vitro influence of a dose rate variation during conventional radiotherapy or carbon ion hadrontherapy treatment in order to improve the therapeutic care of patient. In this regard, two HNSCC cell lines were irradiated with photons or 72MeV/n carbon ions at a dose rate of 0.5, 2 or 10Gy/min.For both radiosensitive and radioresistant cells, the change in dose rate significantly affected cell survival in response to photon exposure, this variation of radiosensitivity was associated to the number of initial and residual DNA double-strand breaks. By contrast, the dose rate change did not affect neither cell survival nor the residual DNA double-strand breaks after carbon ion irradiation. As a result, the Relative Biological Efficiency at 10% survival increased when the dose rate decreased.In conclusion, in the radiotherapy treatment of HNSCC, it is advised to remain very careful when modifying the classical schemes towards altered-fractionation. At the opposite, as the dose rate does not seem to have any effects after carbon ion exposure, there is less need to adapt hadrontherapy treatment planning during active system irradiation

【 授权许可】

Unknown