Figure 1.
The different dose components of the MRT beam.
MRT ‘peak’ & ‘valley’doses, This profile was generated from our GEANT4 Monte Carlo computer simulations of the dose distribution for a 25×25 mm array of 25/175 µm microbeams at a depth of 2 mm in a water phantom. The Supporting Information section contains more detailed information on the simulations.
Figure 2.
Clonogenic survival of EMT6.5, 4T1.2 and NMuMG cells following conventional/synchrotron broadbeam and MRT irradiations.
(A) EMT6.5 tumour, (B) 4T1.2 tumour and (C) NMuMG normal mouse mammary epithelial cells. BB doses were chosen to match the MRT valley dose, based on Monte Carlo computer simulations. Clonogenic survival for 150/50 µm<175/25 µm<BB. 7.5 Gy Synchrotron BB significantly reduced clonogenic survival compared to 7.5 Gy conventional BB (p<0.0001). Data are represented as mean ± SEM (n = 3).
Figure 3.
Comparison of cell proliferation response by xCELLigence assays following BB and MRT irradiations.
(A) EMT6.5 tumour, (B) 4T1.2 tumour and (C) NMuMG normal mouse mammary epithelial cells following synchrotron BB or MRT 175/25 µm and MRT 150/50 µm irradiation. BB doses were similar to the MRT valley dose determined by Monte Carlo modelling. For all cell lines, the reduction in cell index for 150/50 µm>175/25 µm>BB. Data are represented as mean ± SEM (n = 3).
Table 1.
Interpolated equivalent broadbeam doses for increasing MRT doses.
Table 2.
Interpolated equivalent broadbeam doses for increasing MRT doses.
Figure 4.
Testing for dose equivalence between BB and MRT by clonogenic assays.
Comparison of clonogenic survival of (A) EMT6.5ch tumour, (B) 4T1Ch5 tumour and (C) SaOS-2 tumour cells following MRT 175/25 or synchrotron BB at equivalent doses. Data are represented as mean ± SEM for EMT6.5ch (n = 3), 4T1Ch5 (n = 3) and SaOS-2 (n = 2); *p<0.05. EMT6.5ch – mouse mammary tumour cells, 4T1Ch5– mouse mammary tumour cells, SaOS-2– osteocarcinoma cells.
Figure 5.
Testing for dose equivalence between BB and MRT by xCELLigence assays.
Comparison of cell proliferation response by xCELLigence assays of (A) EMT6.5ch tumour, (B) 4T1Ch5 tumour and (C) SaOS-2 tumour cells following MRT 175/25 or synchrotron BB irradiation at equivalent doses. Data are represented as mean ± SEM (n = 3); *p<0.05. EMT6.5ch–mouse mammary tumour cells, 4T1Ch5–mouse mammary tumour cells, SaOS-2–osteocarcinoma cells.
Table 3.
Interpolated equivalent broadbeam doses for increasing MRT doses.
Table 4.
Interpolated equivalent broadbeam doses for increasing MRT doses.