Format

Send to

Choose Destination
Nat Commun. 2019 Sep 4;10(1):3986. doi: 10.1038/s41467-019-12042-7.

Proton-dynamic therapy following photosensitiser activation by accelerated protons demonstrated through fluorescence and singlet oxygen production.

Author information

1
Department of Radiation Biology, Institute for Cancer Research, Radium Hospital, Oslo University Hospital, Montebello, 0379, Oslo, Norway.
2
Department of Physics, University of Oslo, Blinderrn, 0315, Oslo, Norway.
3
Department of Medical Physics, Oslo University Hospital, Montebello, 0379, Oslo, Norway.
4
Department of Radiation Biology, Institute for Cancer Research, Radium Hospital, Oslo University Hospital, Montebello, 0379, Oslo, Norway. ththeo@rr-research.no.

Abstract

We demonstrate excitation of photosensitisers (PSs) by accelerated protons to produce fluorescence and singlet oxygen. Their fluorescence follows a pattern similar to the proton energy loss in matter, while proton-derived fluorescence spectra match the photon-induced spectra. PSs excited in dry gelatin exhibit enhanced phosphorescence, suggesting an efficient PSs triplet state population. Singlet oxygen measurements, both optically at ~1270 nm and through the photoproduct of protoporphyrin IX (PpIX), demonstrate cytotoxic singlet oxygen generation by proton excitation. The singlet oxygen-specific scavenger 1,4-diazabicyclo[2.2.2]octane (DABCO) abrogates the photoproduct formation under proton excitation, but cannot countermand the overall loss of PpIX fluorescence. Furthermore, in two cell lines, M059K and T98G, we observe differential cell death upon the addition of the PS cercosporin, while in U87 cells we see no effect at any proton irradiation dose. Our results pave the way for a novel treatment combining proton therapy and "proton-dynamic therapy" for more efficient tumour eradication.

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central Icon for Norwegian BIBSYS system
Loading ...
Support Center