LET-dependent radiosensitization effects of gold nanoparticles for proton irradiation.
The development of new modalities and protocols is of major interest to improve the outcome of cancer treatment. Given the appealing physical properties of protons and the emerging evidence of biological relevance of the use of gold nanoparticles (GNPs), the radiosensitization effects of GNPs (5 or 10 nm) have been investigated in vitro in combination with a proton beam of different linear energy transfer (LET). After the incubation with GNPs for 24 h, nanoparticles were observed in the cytoplasm of A431 cells exposed to 10 nm GNPs, and in the cytoplasm as well as the nucleus of cells exposed to 5 nm GNPs. Cell uptake of 0.05 mg ml-1of GNPs led to 0.78 pg Au/cell and 0.30 pg Au/cell after 24 h incubation for 10 and 5 nm GNPs respectively. A marked radiosensitization effect of GNPs was observed with 25 keV μm-1protons, but not with 10 keV μm-1protons. This effect was more pronounced for 10 nm GNPs than for 5 nm GNPs. By using a radical scavenger, a major role of reactive oxygen species in the amplification of the death of irradiated cell was identified. All together, these results open up novel perspectives for using high-Z metallic NPs in protontherapy.
Research center for the Physics of Matter and Radiation (PMR-LARN), Namur Research Institute For Life Science (NARILIS), University of Namur, B-5000 Namur, Belgium.
Sha
S
Li
Sébastien
S
Penninckx
Linda
L
Karmani
Anne-Catherine
AC
Heuskin
Kassandra
K
Watillon
Riccardo
R
Marega
Jerome
J
Zola
Valentina
V
Corvaglia
Geraldine
G
Genard
Bernard
B
Gallez
Olivier
O
Feron
Philippe
P
Martinive
Davide
D
Bonifazi
Carine
C
Michiels
Stéphane
S
Lucas