The Study of Effectiveness of Combined Proton-Neutron Irradiation of Tumor Cells In Vitro.

Combined proton-neutron therapy can be the best opportunity for neutron radiation therapy due to highly conformal proton irradiation and high relative biological effectiveness of neutrons. The study compares 4 schemes of sequential in vitro exposure of Chinese hamster fibrosarcoma cells B14-150 to 14.5 MeV neutrons and a scanning beam of protons.

Biological Response of Chinese Hamster B14-150 Cells to Sequential Combined Exposure to Protons and C Ions.

Proton and ion radiation therapy, when used both as single radiation and in mixed radiation mode, have a number of advantages over the conventional γ-therapy that are determined by physical characteristics of accelerated particles. The paper presents the results of an in vitro study of the effectiveness of sequential exposures of Chinese hamster tumor cells B14-150 to proton (p) and C ion beams. We used 4 irradiation schemes differing by the sequence of exposure and the contribution of each radiation to the total dose.

Post-Irradiation Recovery of B14-150 Fibrosarcoma Cells after Combined Irradiation with Low and High Linear Energy Transfer.

The use of radiation with low and high linear energy transfer (LET) in the same treatment regimen is promising in terms of increasing the efficiency and reducing the severity of radiation complications. Here we studied combined effect of protons (LET≈3 keV/μm) and heavy recoils (HR) induced by 14.5 MeV neutrons (LET≈290 keV/μm) on B14-150 fibrosarcoma cells.

Hypersensitivity and Induced Radioresistance in Chinese Hamster Cells Exposed to Radiations with Different LET Values.

We study the impact of radiation LET on manifestation of HRS/IRR response in Chinese hamster cells ovary cells exposed to radiations used in radiotherapy. Earlier we have investigated this response to carbon ions (455 MeV/amu) in the pristine Bragg curve plateau and behind the Bragg peak, 60Co γ-rays, and 14.5 MeV neutrons.

Dose Field Shaping and Biological Effectiveness of the Effect of Pulsed Electron Accelerator Novac-11 on Mammalian Cells.

The development of technologies for using the Novac-11 pulsed electron accelerator in radiation therapy of animals with spontaneous neoplasms requires dosimetric and radiobiological studies. The studies were performed on cultured Chinese hamster V-79 fibroblasts after irradiation with 10 MeV electrons in a dose range up to 12 Gy and Co γ-radiation. Chemical dosimeters FBX and Fricke were used as additional test-systems.

In vitro modified microdosimetric kinetic model-based predictions for B14-150 cells survival in 450 MeV/u carbon ion beam with aluminum ridge filter for biologically optimized spread-out Bragg peak.

The relative biological efficiency of particle irradiation could be predicted with a wide variety of radiobiological models for various end-points. We validate the forecast of modified Microdosimetric Kinetic Modelusing combined data of reference Co-60 radiation and carbon ion plateau data for specific cell line to optimize the survival function in spread-out Bragg Peak obtained with an especially designed ridge filter. We used Geant4 Monte-Carlo software to simulate the fragment contribution along Bragg curve inside water phantom, open-source toolkit Survival to predict the expected linear-quadratic model parameters for each fragment, and in-house software to form the total survival curve in spread-out Bragg Peak.

Evaluation of Antitumor Efficiency of High Intensity Radiation Yb Source on Experimental Sarcoma M-1.

Rats with sarcoma M-1 were exposed to high dose rate irradiation with Yb source. In 25 days after introduction of a trocar with sealed capsule with Yb source into the tumor, complete tumor regression was observed in 70% animals. The results suggest feasibility of using Yb source for high-dose rate brachytherapy and development of the personalized medicine approaches.